Quality Improvement Guidelines for Radiofrequency Ablation of Liver Tumours

The development of image-guided percutaneous techniques for local tumour ablation has been one of the major advances in the treatment of liver malignancies. Among these methods, radiofrequency ablation (RFA) is currently established as the primary ablative modality at most institutions. RFA is accepted as the best therapeutic choice for patients with early-stage hepatocellular carcinoma (HCC) when liver transplantation or surgical resection are not suitable options [1, 2]. In addition, RFA is considered a viable alternate to surgery (1) for inoperable patients with limited hepatic metastatic disease, especially from colorectal cancer, and (2) for patients deemed ineligible for surgical resection because of extent and location of the disease or concurrent medical conditions [3]. These guidelines were written to be used in quality-improvement programs to assess RFA of HCC and liver metastases. The most important processes of care are (1) patient selection, (2) performing the procedure, and (3) monitoring the patient. The outcome measures or indicators for these processes are indications, success rates, and complication rates.     

Survival after Radiofrequency Ablation in 122 Patients with Inoperable Colorectal Lung Metastases

Purpose

To analyze the factors associated with favorable survival in patients with inoperable colorectal lung metastases treated with percutaneous image-guided radiofrequency ablation.

Methods

Between 2002 and 2011, a total of 398 metastases were ablated in 122 patients (87 male, median age 68 years, range 29–90 years) at 256 procedures. Percutaneous CT-guided cool-tip radiofrequency ablation was performed under sedation/general anesthesia. Maximum tumor size, number of tumors ablated, number of procedures, concurrent/prior liver ablation, previous liver or lung resection, systemic chemotherapy, disease-free interval from primary resection to lung metastasis, and survival from first ablation were recorded prospectively. Kaplan–Meier analysis was performed, and factors were compared by log rank test.

Results

The initial number of metastases ablated was 2.3 (range 1–8); the total number was 3.3 (range 1–15). The maximum tumor diameter was 1.7 (range 0.5–4) cm, and the number of procedures was 2 (range 1–10). The major complication rate was 3.9 %. Overall median and 3-year survival rate were 41 months and 57 %. Survival was better in patients with smaller tumors—a median of 51 months, with 3-year survival of 64 % for tumors 2 cm or smaller versus 31 months and 44 % for tumors 2.1–4 cm (p = 0.08). The number of metastases ablated and whether the tumors were unilateral or bilateral did not affect survival. The presence of treated liver metastases, systemic chemotherapy, or prior lung resection did not affect survival.

Conclusion

Three-year survival of 57 % in patients with inoperable colorectal lung metastases is better than would be expected with chemotherapy alone. Patients with inoperable but small-volume colorectal lung metastases should be referred for ablation.     

Quality Improvement Guidelines for Placement of Esophageal Stents

Esophageal cancer is now the sixth leading cause of death from cancer worldwide [1, 2]. During the past three decades, important changes have occurred in the epidemiologic patterns associated with this disease [1]. Due to the distensible characteristics of the esophagus, patients may not recognize any symptoms until 50% of the luminal diameter is compromised, explaining why cancer of the esophagus is generally associated with late presentation and poor prognosis [3]. Esophageal cancer has a poor outcome, with an overall 5 year survival rate of less than 10%, and fewer than 50% of patients are suitable for resection at presentation. As a result palliation is the best option in this group of patients [3, 4]. The aims of palliation are maintenance of oral intake, minimizing hospital stay, relief of pain, elimination of reflux and regurgitation, and prevention of aspiration [3, 5, 6]. For palliative care, current treatment options include thermal ablation [7–9], photodynamic therapy [10–12], radiotherapy [13], chemotherapy [14, 15], chemical injection therapy [16–18], argon beam or bipolar electrocoagulation therapy [19], enteral feeding (nasogastric tube/percutaneous endoscopic gastrostomy) [20–22], and intubation (self-expanding metal stents (SEMS) or semi-rigid prosthetic tubes) [5, 6, 23–26] with different success and complications rates.     

Charlson Comorbidity Index predicts patient outcome,in cases of inoperable non-small cell lung cancer treated with radiofrequency ablation

Purpose

The Charlson Comorbidity Index (CCI) has been shown to be a significant prognostic indicator in the treatment of many types of cancer. The aim of this study is to evaluate the degree to which the CCI predicts survival in patients with inoperable non-small cell lung cancer (NSCLC) treated with radiofrequency ablation (RFA).

Materials and methods

Eighty-two (34 men, 48 women) consecutive RFA treatments for medically inoperable NSCLC were performed at our institution from 1/1/2000 to 1/30/2009. With institutional IRB approval and in full HIPAA compliance, the medical records of these patients were examined for data relating to pre-treatment comorbid conditions, and a retrospective analysis was conducted. Survival curves were estimated by the Kaplan–Meier method. Risk factors for mortality were determined by single-factor comparisons of curves using Wilcoxon-weighted chi-square and multiple Cox regressions.

Results

The patients ranged in age from 59 to 91 years (mean: 75.5). Eighty-eight percent (72 patients) were tumor stage IA or IB. Patients were followed for a total of five years; three-year overall survival was 50.6%. Hospital mortality was 0%. Gender, stage, histology and CCI score were each associated with significantly impaired survival (p < 0.001 in all cases). After covarying for age, tumor stage > IB, squamous histology and gender, multiple Cox regressions showed that an increasing CCI score was significantly associated with an increased risk of death (HR 1.3, 95% CI 25.5, 58.2).

Conclusions

The CCI is validated as an important, independent predictor of patient survival, in cases of inoperable NSCLC treated with RFA.     

Combined utility of one lung ventilation and artificial pneumothorax in thermal ablation of hepatic dome tumor: a technical note

Radiofrequency ablation and microwave ablation are established treatment modalities for smaller (<3 cm) or isolated hepatic tumors. Transthoracic ablation of hepatic dome lesions is a well described technique. We report the use of one lung ventilation to facilitate the successful percutaneous transthoracic microwave ablation of a segment 8 hepatic dome lesion after induction of artificial pneumothorax. This involved the use of general anesthesia and insertion of a double lumen endotracheal tube to allow isolated ventilation of one lung, followed by creation of an artificial pneumothorax under computed tomography (CT) guidance. Complete ablation of the lesion was confirmed on CT liver at 1 and 7 months with no local recurrence. The combined techniques of one lung ventilation and artificial pneumothorax enabled a safe and accurate transthoracic targeting of the hepatic dome lesion.

Thermal ablation techniques such as radiofrequency ablation (RFA) and microwave ablation (MWA) are alternative treatment options for patients with small (<3 cm) or isolated lesions. Transthoracic ablation of lesions is safe and effective for treatment of hepatic dome lesions.Current standard of practice in most centers is the administration of local anesthesia with moderate conscious sedation for percutaneous RFA or MWA. Thermal ablation under sedation is poorly tolerated in patients whose lesions are more than 3 cm in size or in the sub-diaphragmatic location, commonly requiring conversion to general anesthesia due to pain on ablation and/or need for controlled apnea to allow for accurate targeting of the lesion (1). Additionally, incomplete ablation of tumors is more common in procedures with sedation compared to general anesthesia (1).Even under general anesthesia, hepatic dome lesion targeting is affected by the constant respiratory movements of the liver and diaphragm. We report the use of one-lung ventilation (OLV) to facilitate safe and successful transthoracic percutaneous computed tomography (CT)-guided MWA of a hepatic dome hepatocellular carcinoma (HCC) lesion after induction of artificial pneumothorax to avoid injury to the lung and visceral pleura.     

Radiofrequency ablation for lung tumors: outcomes,effects on survival,and prognostic factors

PURPOSE

We aimed to evaluate the survival benefit achieved with radiofrequency (RF) ablation of primary and metastatic lung tumors and determine significant prognostic factors for recurrence-free survival.

METHODS

Forty-nine patients with lung cancer (10 primary and 39 metastatic) underwent computed tomography-guided percutaneous RF ablation between June 2005 and October 2013. A total of 112 tumors (101 metastatic and 11 primary non-small cell lung cancer) were treated with RF ablation. Tumor diameter ranged from 0.6 to 4 cm (median 1.5 cm). Effectiveness of treatment, complications, and survival were analyzed.

RESULTS

Primary success rate was 79.5% and local tumor progression occurred in 23 tumors. Among tumors showing progression, 10 were re-treated with RF ablation and secondary success rate was 87.5%. One-, two-, and three-year overall survival rates of 10 patients with primary lung cancer were 100%, 86%, and 43%, respectively. One-, two-, three-, four-, and five-year overall survival rates for 39 patients with metastatic lung tumors were 90%, 73%, 59%, 55%, and 38%, respectively. One-, two-, three-, and four-year overall survival rates for 16 patients with colorectal pulmonary metastases were 94%, 80%, 68%, and 23%, respectively. Complications occurred in 30 sessions (24.6%). Pneumothorax occurred in 19 sessions with seven requiring image-guided percutaneous chest tube drainage. Tumor status (solitary or multiple) and presence of extrapulmonary metastasis at initial RF ablation were significant prognostic factors in terms of recurrence-free survival.

CONCLUSION

RF ablation is a safe and effective treatment with a survival benefit for selected patients with primary and secondary lung tumors.Primary lung cancer is the leading cause of cancer-related death worldwide (1). Treatment of primary lung cancers includes surgical resection, radiation therapy, chemotherapy, and thermal ablation. Surgical resection remains the treatment of choice for patients with early stage non-small cell lung cancer (NSCLC) (2). However, primary lung cancers are generally diagnosed in advanced stages. Moreover, due to the high incidence of associated comorbidities and limited pulmonary reserve, most patients are considered ineligible for surgery (3, 4).In addition to primary cancers, lungs are the second most frequent site of metastatic disease. In selected patients with metastatic lung cancer, surgical resection is the preferred treatment. However, even patients who have undergone a complete resection have a high incidence of recurrence and may require multiple surgeries (5). Repeat thoracotomy leads to further removal of functional pulmonary tissue. Surgical resection might not be possible in patients with certain comorbidities and limited pulmonary reserve.Patients with pulmonary colorectal metastases constitute a significant portion of metastatic lung tumor group. Approximately 10% of patients with colorectal cancer develop pulmonary metastases during the course of disease (6). It has been reported that in patients with limited colorectal pulmonary metastases and no extrapulmonary disease, five-year survival following surgical resection is approximately 35%–45% (7). However, many patients are not suitable candidates for surgery.Percutaneous image-guided radiofrequency (RF) ablation is a minimally invasive technique established in the treatment of solid tumors. Since Dupuy et al. (8) reported the first clinical use of RF ablation to treat lung cancer in 2000, it has been increasingly used as a treatment option for patients with primary and secondary lung tumors, who are not surgical candidates. RF ablation offers reduced morbidity and mortality, and allows preservation of pulmonary functions because surrounding uninvolved lung parenchyma is preserved (9, 10). It is very useful for patients who have limited pulmonary reserve or with multifocal or bilateral metastatic disease. It is performed with computed tomography (CT) guidance and avoids thoracotomy in patients with significant comorbidities or in patients who refuse surgery. Repeatability of the procedure is a great advantage (11). It can be performed on an outpatient basis or with a minimum hospital stay (12).The aim of this study was to evaluate the survival benefit achieved with RF ablation for primary and secondary lung tumors and determine significant prognostic factors in terms of recurrence-free survival.     

Radiofrequency ablation of pulmonary tumors

The development of image-guided percutaneous techniques for local tumor ablation has been one of the major advances in the treatment of solid tumors. Among these methods, radiofrequency (RF) ablation is currently established as the primary ablative modality at most institutions. RF ablation is accepted as the best therapeutic choice for patients with early-stage hepatocellular carcinoma when liver transplantation or surgical resection are not suitable options and is considered as a viable alternate to surgery for inoperable patients with limited hepatic metastatic disease, especially from colorectal cancer. Recently, RF ablation has been demonstrated to be a safe and valuable treatment option for patients with unresectable or medically inoperable lung malignancies. Resection should remain the standard therapy for non-small cell lung cancer (NSCLC) but RF ablation may be better than conventional external-beam radiation for the treatment of the high-risk individual with NSCLC. Initial favourable outcomes encourage combining radiotherapy and RF ablation, especially for treating larger tumors. In the setting of colorectal cancer lung metastases, survival rates provided by RF ablation in selected patients, are substantially higher than those obtained with any chemotherapy regimens and provide indirect evidence that RF ablation therapy improves survival in patients with limited lung metastatic disease.     

Ultrasound-Guided Glue Injection as Alternative Treatment of Femoral Pseudoaneurysms

The interventional angiographic techniques using the percutaneous femoral approach for endovascular revascularization are becoming increasingly more popular. These methods usually require larger sheaths, and most patients need postprocedural anticoagulation or antiplatelet therapy. As a consequence, the interventional procedure is associated with a higher rate of complications at the arterial entry site compared to diagnostic angiography [1,2]. The reported incidence of iatrogenic pseudoaneurysm formation after coronary artery interventions ranges from 3.2% [1] to 7.7% [3], and the rates noted after diagnostic angiography range from 0.2% [1] to 1% [4].Peripheral pseudoaneurysms have traditionally been treated by surgical intervention, but nonsurgical alternatives, such as ultrasound (US)-guided compression, coil embolization, stent-graft placement, and percutaneous thrombin injection with or without balloon occlusion have also been documented. Of these alternatives, direct percutaneous embolization with embolic agents is the most popular method. The tissue adhesive n-butyl cyanoacrylate (NBCA) (Hystoacryl) (B. Braun, Melsungen, Germany) is one of the most popular occluding agents for neurovascular interventions, and has been widely used for more than 20 years [5,6]. In this study, we evaluated the efficacy and utility of direct percutaneous injection of NBCA for embolization of femoral pseudoaneurysms.     

Radiofrequency ablation for single lung tumours not suitable for surgery: seven years’ experience

Purpose

This study was done to review recurrence patterns in patients with lung cancer (primary or secondary) treated with percutaneous image-guided radiofrequency (RF) ablation.

Materials and methods

From January 2003 to August 2010, 32 patients (24 with primary non-small-cell lung cancer and eight with metastases) with single lung cancer were treated with RF ablation. Post-treatment imaging results were available for each patient. Follow-up was performed using computed tomography (CT) scans at 1, 3, 6, 12, 18 and 24 months after the procedure and annually thereafter. Patterns of recurrence were classified as local, intrapulmonary, nodal, mixed and distant. We evaluated overall survival after RF ablation and the factors associated with recurrence.

Results

Seventeen (53.1%) patients showed no evidence of recurrence at follow-up imaging (range 12-72 months; mean, 32.5 months). Recurrence was seen in 15 (46.9 %) patients (range 6-36 months; mean 14.8 months). Local recurrence (40%) after RF ablation was the most frequent. Median disease-free survival was 20 months. Sex, tumour location, tumour size and tumour stage were not associated with a risk of recurrence. Patient age was related to the risk of recurrence (p<0.05).

Conslucions

Local recurrence is the most common pattern in our series. A more aggressive initial RF ablation might offer improvement in outcomes, but this hypothesis needs to be confirmed by larger studies involving a larger number of patients.     

CT-guided percutaneous cryoablation of central lung tumors

PURPOSE

Cryoablation has been successfully used to treat lung tumors. However, the safety and effectiveness of treating tumors adjacent to critical structures has not been fully established. We describe our experience with computed tomography (CT)-guided percutaneous cryoablation of central lung tumors and the role of ice ball monitoring.

MATERIALS AND METHODS

Eight patients with 11 malignant central lung tumors (nine metastatic, two primary; mean, 2.6 cm; range, 1.0–4.5 cm) located adjacent to mediastinal or hilar structures were treated using CT-guided cryoablation in 10 procedures. Technical success and effectiveness rates were calculated, complications were tabulated and intraprocedural imaging features of ice balls were described.

RESULTS

All procedures were technically successful; imaging after 24 hours demonstrated no residual tumor. Five tumors recurred, three of which were re-ablated successfully. A hypodense ice ball with well-defined margin was visible during the first (n=6, 55%) or second (n=11, 100%) freeze, encompassing the entire tumor in all patients, and abutting (n=7) or minimally involving (n=4) adjacent mediastinal and hilar structures. Pneumothorax developed following six procedures (60%); percutaneous treatment was applied in three of them. All patients developed pleural effusions, with one patient requiring percutaneous drainage. Transient hemoptysis occurred after six procedures (60%), but all cases improved within a week. No injury occurred to mediastinal or hilar structures.

CONCLUSION

CT-guided percutaneous cryoablation can be used to treat central lung tumors successfully. Although complications were common, they were self-limited, treatable, and not related to tumor location. Ice ball monitoring helped maximize the amount of tumor treated, while avoiding critical mediastinal and hilar structures.Malignant lung tumors represent a major cause of morbidity and mortality in developed nations (1). While surgical resection remains the treatment of choice for the local control of both non-small cell lung cancer and metastases to the lung, percutaneous image-guided ablative therapies, particularly heat-based ablation techniques such as radiofrequency (RF) ablation, have emerged as safe and effective alternatives in patients who are not surgical candidates (2–7). However, treatment of lung tumors using RF ablation presents technical challenges, including high electrical resistance of alveolar air, poor thermal conductivity of aerated lung, and the heat-sink effect of blood and air flow in well-perfused and aerated lung tissue (8, 9). In addition, RF ablation has a limited role in the treatment of tumors that are close to mediastinal and hilar structures (2–9). Since intraprocedural visualization of ablation zone margins is not possible during heat-based ablation procedures, treatment of central tumors could harm mediastinal and hilar structures, including the tracheobronchial tree. As a result, tumors close to central structures are generally not amenable to treatment using percutaneous heat-based ablation techniques (2–10). Also, RF ablation may interfere with conduction system of the heart and function of the pacemakers (11).A growing body of literature describes the successful use of cryoablation in the treatment of malignancies in the liver, kidneys, and soft tissues (12–14). The ability to deploy multiple, individually-controlled cryoablation applicators facilitates the creation of ablation zones of desired shapes and sizes that can be tailored to the morphology of the tumor being ablated (15, 16). Cryoablation is also monitorable; ice balls can be visualized by computed tomography (CT) as a distinct ovoid area of low attenuation during the procedure. As a result, the treatment can be optimized while minimizing the risk of harming nearby critical structures (12–16). Also, cryoablation may be less painful than RF ablation (17). Finally, it has been suggested that cryoablation may be better suited for the treatment of thoracic tumors adjacent to the mediastinum because it spares the architecture of collagen-containing structures relative to RF ablation and enables preservation of the integrity of the tracheobroncheal tree (18). Heat-based ablation methods may not be safe in the treatment of central lung tumors because of a possibility of bronchial disruption or perforation, which may result in bronchopleural fistula formation (19). Although cryoablation has been used to treat lung malignancies (19–31), there are limited data on the safety and effectiveness of percutaneous cryoablation of central lung tumors. In this study, we describe our experience with CT-guided percutaneous cryoablation of central lung tumors and the role of ice ball monitoring.     

Prozessorientierte Kostenrechnung in der Interventionellen Radiologie

Purpose

Currently used costing methods such as cost centre accounting do not sufficiently reflect the process-based resource utilization in medicine. The goal of this study was to establish a process-oriented cost assessment of percutaneous radiofrequency (RF) ablation of liver and lung metastases.

Material and methods

In each of 15 patients a detailed task analysis of the primary process of hepatic and pulmonary RF ablation was performed. Based on these data a dedicated cost calculation model was developed for each primary process. The costs of each process were computed and compared with the revenue for in-patients according to the German diagnosis-related groups (DRG) system 2010.

Results

The RF ablation of liver metastases in patients without relevant comorbidities and a low patient complexity level results in a loss of EUR 588.44, whereas the treatment of patients with a higher complexity level yields an acceptable profit. The treatment of pulmonary metastases is profitable even in cases of additional expenses due to complications.

Conclusion

Process-oriented costing provides relevant information that is needed for understanding the economic impact of treatment decisions. It is well suited as a starting point for economically driven process optimization and reengineering. Under the terms of the German DRG 2010 system percutaneous RF ablation of lung metastases is economically reasonable, while RF ablation of liver metastases in cases of low patient complexity levels does not cover the costs.     

Percutaneous radiofrequency ablation for patients with malignant lung tumors: a phase II prospective multicenter study (JIVROSG-0702)

Purpose

This prospective multicenter study aimed to evaluate the efficacy and safety of percutaneous radiofrequency (RF) ablation for lung cancer.

Materials and methods

From May 2008 to April 2012, 33 patients (26 men, 7 women; mean age 70.5 years) were enrolled. RF ablation was performed using an internally cooled or expandable multitined electrode. The primary endpoint was complete response (CR) determined using ¹⁸F fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) performed 6 months after RF ablation. The secondary endpoint was the incidence and grade of adverse events (AEs) evaluated using the Common Toxicity Criteria for Adverse Events, version 3.0.

Results

All patients underwent RF ablation and had efficacy analyses evaluated; however, FDG-PET/CT images before RF ablation were not available for two patients. The CR rate was 68 % (21 of 31 patients). One patient had a grade 5 AE unrelated to RF ablation. Grade ≥3 AEs occurred in 12 % of patients. During the follow-up period (median 37 months; range 1–55 months), five patients developed local tumor progression and nine (29 %) died. Overall survival at 1, 2, and 3 years was 97, 82, and 74 %, respectively.

Conclusion

Percutaneous RF ablation is a safe, feasible, and effective treatment for small malignant lung tumors.

     

Biplane fluoroscopy-guided radiofrequency ablation combined with chemoembolisation for hepatocellular carcinoma: initial experience

Objective

The purpose of this study was to assess the technical feasibility and local efficacy of biplane fluoroscopy-guided percutaneous radiofrequency (RF) ablation combined with transcatheter arterial chemoembolisation (TACE) for hepatocellular carcinoma (HCC).

Method

Our retrospective study was approved by the institutional review board and informed consent was waived. 18 patients with 19 HCCs (mean 2.5 cm diameter; range 2–4.2 cm) were treated with percutaneous RF ablation combined with TACE. After segmental TACE, 18 (95%) of 19 HCCs were visible on fluoroscopy. Shortly (median 2 days; range 1–4 days) after TACE, percutaneous RF ablation was performed under real-time biplane fluoroscopic guidance. We evaluated major complications, rate of technical success at immediate post-RF ablation CT images and local tumour progression at follow-up CT images.

Results

Major complication was not observed in any patients. Technical success was achieved for all 18 visible HCCs. During the follow-up period (median 20 months; range 5–30 months), no local tumour progression was found.

Conclusion

Biplane fluoroscopy-guided RF ablation combined with TACE is technically feasible and effective for treatment of HCC.Percutaneous radiofrequency (RF) ablation has been widely implemented in the management of hepatocellular carcinoma (HCC) with promising results. Although its local efficacy for small tumours (i.e. <2 cm) is similar to surgical outcomes [1], results for medium-sized and large tumours are less robust. Thus, multimodal treatments such as combined percutaneous RF ablation with transarterial chemoembolisation (TACE) have been explored for medium or large HCCs in order to enhance the therapeutic effect. In a recent study, RF ablation combined with TACE was similar to surgical resection in patients with early-stage disease [2].Percutaneous RF ablation shortly following TACE has been usually performed under guidance of either ultrasonography or CT/CT fluoroscopy. Since intratumoural retention of radio-opaque iodised oil induced by TACE conveniently provides radiographic contrast to the index lesion, biplane fluoroscopy (anterior posterior and lateral projections) can be used as an alternative guiding modality for RF ablation combined with TACE. Easier targeting of dome lesions, often difficult to visualise on ultrasound, through an oblique approach without pleural transgression is one potential advantage of biplane fluoroscopy guidance. Also unlike on ultrasound, microbubble formation during ablation would not obscure the index lesion on biplane fluoroscopy, allowing easier and more spatially accurate application of overlapping ablations that are often needed for larger tumours. However, to our knowledge, there have been no studies investigating the role of biplane fluoroscopy as a guidance modality in this clinical setting. The purpose of our study was to retrospectively assess the technical feasibility and local efficacy of biplane fluoroscopy-guided percutaneous RF ablation combined with TACE for HCC ≥2 cm.     

Retrospective Review of Percutaneous Image-Guided Ablation of Oligometastatic Prostate Cancer: A Single-Institution Experience

Purpose

To retrospectively review and report the efficacy and safety of percutaneous image-guided ablation (cryoablation or radiofrequency ablation) in the treatment of oligometastatic prostate cancer.

Image-guided microwave ablation of hepatic tumours: preliminary experience

Purpose

Microwave thermal ablation (MWA) opens up a new scenario in the field of image-guided tumour ablation thanks to its potential advantages over validated radiofrequency ablation (RFA). In this pilot study, we assessed the technical success, safety and efficacy of MWA in treating hepatic malignancies.

Materials and methods

After obtaining informed consent, we enrolled 15 inoperable patients, for a total of 19 lesions (ten metastases, nine hepatocellular carcinoma) with a mean diameter of 47 mm (range 14?C78 mm). Mean follow-up was 8 (range 1?C14) months.

Results

Technical success reached 100%. Complications (one major and one minor) occurred in two cases. Complete ablation, obtained in 68.4% of cases, showed no significant correlation with either cancer histological type or with lesion diameter. At follow-up, treatment failures occurred in 60% of cases; lesion diameter was the only prognostic factor for maintaining complete ablation.

Conclusions

Our preliminary results should encourage further trials of this technique. MWA proved to be feasible and safe in treating advanced-stage liver tumours and represented an additional therapeutic attempt to be validated in further and larger efficacy studies.     

Percutaneous radiofrequency ablation of lung tumors with expandable needle electrodes: current status

Percutaneous radiofrequency thermal ablation (RFA) has been used to treat primary and secondary liver tumors under ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI) guidance for the past decade [Park et al., Radiol Clin North Am 38:545–561, 2000; Siperstein and Gotomirski, Cancer J 6:S293–S301, 2000; Kelekis et al., Eur Radiol 13:1100–1105, 2003]. RFA is a low-cost, minimally invasive treatment that has recently attracted attention for treating tumors in different solid organs with promising results [Dupuy and Goldberg, J Vasc Interv Radiol 12:1135–1148, 2001; Friedman et al., Cardiovasc Intervent Radiol 27:427–434, 2004]. It can be provided with minimal hospitalization, and experienced practitioners have reported low complication rates [Dupuy and Goldberg, J Vasc Interv Radiol 12:1135–1148, 2001; Livraghi et al., Radiology 226:441–451, 2003]. Patients with lung malignancies (primary lung cancer or pulmonary metastases), who cannot be operated, might be candidates for RFA treatment. It can also be used in association with other treatments (i.e., chemotherapy, radiotherapy) for better disease control. Combination of the above with RFA may help reduce morbidity and mortality. Many ways to apply energy to the tumor exist (monopolar and bipolar RFA, microwave, laser, brachytherapy). In this review we will focus on expandable monopolar systems, which despite their deficiencies are the most popular in the interventional radiology sector.     

Evaluation of carcinoembryonic antigen (CEA) density as a prognostic factor for percutaneous ablation of pulmonary colorectal metastases

Objectives

To evaluate the prognostic value of carcinoembryonic antigen (CEA) density and other clinicopathological factors for percutaneous ablation of pulmonary metastases from colorectal cancer.

Methods

CEA density was calculated as: “absolute serum CEA pre-ablation/volume of all lung metastases [mm³]”. Median CEA density was the cut-off for high and low groups. Cox-regression was used to determine prognostic factors for survival.

Results

A total of 85 patients (102 ablation sessions) were followed for a median of 27 months. High CEA density was significantly associated with worse overall survival compared to low CEA density (adjusted HR: 2.12; 95 % CI: 1.22–3.70, p=0.002; median survival: 25.7 vs. 44.3 months). The interval between primary resection of the colorectal carcinoma and first ablation was also a prognostic factor, a duration >24 months being associated with better survival compared to a shorter interval (0–24 months) (adjusted HR: 0.55; 95 % CI: 0.31–0.98, p=0.04). Moreover, a disease-free interval >24 months was significantly associated with low CEA density compared to a shorter interval (0–24 months) (adjusted OR: 0.29; 95 % CI: 0.11–0.77, p=0.01).

Conclusions

Serum CEA density and interval between primary resection of a colorectal carcinoma and pulmonary ablation are independent prognostic factors for overall survival. In two patients with identical CEA serum levels, the patient with the lower/smaller pulmonary tumour load would have a worse prognosis than the one with the higher/larger pulmonary metastases.

Key Points

? CEA density is an independent prognostic factor for colorectal pulmonary metastases. ? A lower CEA density is associated with better overall survival. ? CEA may play a functional role in tumour progression. ? High CEA density is associated with smaller tumours. ? Interval between pulmonary ablation and primary colorectal carcinoma is a prognostic factor.

     

Percutaneous ultrasound-guided thermal ablation for intrahepatic cholangiocarcinoma

Objective

The objective of this study was to evaluate the treatment efficacy and overall survival (OS) of percutaneous ultrasound-guided thermal ablation by means of microwave ablation or radiofrequency ablation for intrahepatic cholangiocarcinoma (ICC).

Methods

18 patients with 25 ICC nodules underwent ultrasound-guided thermal ablation with curative intention. 8 patients were primary cases and 10 were recurrent cases after curative resection. The local treatment response, complications and survivals were analysed.

Results

Complete ablation was achieved in 23 (92.0%, 23/25) nodules (diameter, 0.7–4.3 cm; mean, 2.5±0.9 cm) and incomplete ablation was found in 2 (8.0%, 2/25) larger tumours (6.4 and 6.9 cm in diameter). No death associated with the treatment was found. The major complication rate was 5.5% (1/18). The follow-up periods ranged from 1.3 to 86.2 months (mean, 20.5±26.3 months; median, 8.7 months). OS rates for all patients at 6, 12, 36 and 60 months were 66.7%, 36.3%, 30.3% and 30.3%, respectively. By univariate analysis, the patient source (primary or recurrent case) was found to be a significant prognostic factor for OS rates (p=0.001). The patient source (p=0.001) and the number of nodules (p=0.038) were found to be significant prognostic factors for recurrence-free survival. OS rates for the primary ICC at 6, 12, 36 and 60 months were 87.5%, 75.0%, 62.5% and 62.5%, respectively.

Conclusion

Percutaneous ultrasound-guided thermal ablation is a safe and effective therapeutic technique for ICC. Acceptable survival can be achieved in primary ICCs, whereas the prognosis of recurrent ICCs is relatively poor.Intrahepatic cholangiocarcinoma (ICC) is a malignant tumour that arises from the epithelial cells of intrahepatic bile ducts (beyond the second order bile ducts). It constitutes approximately 5–30% of primary liver cancer, and the worldwide incidence of this malignancy has been increasing in recent years [1-6]. ICC often shows higher malignant grade and poorer prognosis than those of hepatocellular carcinoma (HCC). Until now, surgical resection has been the optimal therapy for ICC, offering a potential for curative treatment. However, many patients with tumours are not candidates for surgical resection because of the advanced stage of the disease at presentation, anatomical limitations and medical comorbidities. The high recurrence rate after resection and the lack of a valid treatment option also contribute to the poor prognosis. Currently there is no randomised study showing a survival benefit for a specific chemotherapeutic regimen. On the other hand, external radiotherapy does not show a significant impact on survival or quality of life [7-9].Image-guided thermal ablation by means of radiofrequency ablation (RFA) or microwave ablation (MWA) has been proven to be a viable option for the treatment of liver cancers, owing to its remarkable advantages, such as minimal invasiveness, easy performance, repeatability and cost-effectiveness [10-13]. In suitable cases, thermal ablation can be used as a curative option for HCC; however, the efficacy of thermal ablation for ICC lacks sufficient evidence [10]. In the present study, we analysed the local treatment response, complications and survival of 18 patients with ICC who had undergone ultrasound-guided thermal ablation.     

Patterns of CT lung injury and toxicity after stereotactic radiotherapy delivered with helical tomotherapy in early stage medically inoperable NSCLC

Objective:

To evaluate toxicity and patterns of radiologic lung injury on CT images after hypofractionated image-guided stereotactic body radiotherapy (SBRT) delivered with helical tomotherapy (HT) in medically early stage inoperable non-small-cell lung cancer (NSCLC).

Methods:

28 elderly patients (31 lesions) with compromised pulmonary reserve were deemed inoperable and enrolled to undergo SBRT. Patterns of lung injury based on CT appearance were assessed at baseline and during follow up. Acute (6 months or less) and late (more than 6 months) events were classified as radiation pneumonitis and radiation fibrosis (RF), respectively.

Results:

After a median follow-up of 12 months (range, 4–20 months), 31 and 25 lesions were examined for acute and late injuries, respectively. Among the former group, 25 (80.6%) patients showed no radiological changes. The CT appearance of RF revealed modified conventional, mass-like and scar-like patterns in three, four and three lesions, respectively. No evidence of late lung injury was demonstrated in 15 lesions. Five patients developed clinical pneumonitis (four patients, grade 2 and one patient, grade 3, respectively), and none of whom had CT findings at 3 months post-treatment. No instance of symptomatic RF was detected. The tumour response rate was 84% (complete response + partial response). Local control was 83% at 1 year.

Conclusion:

Our findings show that HT-SBRT can be considered an effective treatment with a mild toxicity profile in medically inoperable patients with early stage NSCLC. No specific pattern of lung injury was demonstrated.

Advances in knowledge:

Our study is among the few showing that HT-SBRT represents a safe and effective option in patients with early stage medically inoperable NSCLC, and that it is not associated with a specific pattern of lung injury.Surgery is the standard treatment for early stage non-small-cell lung cancer (NSCLC), with an overall survival of about 50–70% in Stage I patients.¹ In clinical practice, however, patients with lung tumours, primary or metastatic, often present with related symptoms, advanced age and associated comorbid conditions. Unfortunately, most of them are excluded from clinical trials that are designed to inform practice, creating major evidence gaps. This clinical scenario is expected to further increase the number of cases in the elderly,^2,3 with the consequence that, if untreated, the survival rates of these patients can be severely poor.⁴ Tackling this population represents a therapeutic challenge, and new opportunities exist to improve the management and outcomes for elderly people with coexisting illnesses. In previous years, there has been much evidence of good outcomes obtained with stereotactic body radiotherapy (SBRT) for primary tumours or metastases in the lung for inoperable patients,^5–8 and the introduction of SBRT has improved population-based survival in Stage I NSCLC.^9,10Among the various treatment delivery units, helical tomotherapy (HT) is a kind of image-guided system that is able to deliver intensity-modulated radiation therapy (IMRT) by combining a continuously rotating fan beam with synchronous couch movement.^11,12 While dosimetric findings have shown that such capabilities can potentially translate into the delivery of an increased tumour dose with doses to normal tissues decreased compared with other techniques,^13,14 only a limited number of patients were included in recent studies that have addressed the feasibility of hypofractionated or ablative RT regimens for lung tumours treated with HT.^15–21 The helical radiation delivery method is associated with low-dose spread¹² to the normal lung and can potentially result in patterns of lung injury that might be different than those observed with conventional three-dimensional conformal RT (3D-CRT) or other SBRT techniques. These latter issues raise some concerns, especially in elderly patients, with frailties or comorbidities, given the risk that the potential benefits of SBRT might be hampered by an increased risk of toxicity that can be life threatening or at least substantially compromise their quality of life.The aim of the present study is to evaluate treatment-related toxicity and patterns of radiologic lung injury on CT images after image-guided SBRT delivered with HT (HT-SBRT) for patients with early stage medically inoperable NSCLC.     

Incidental findings on positron emission tomography/CT scans performed in the investigation of lung cancer

Objectives

This study aimed to clarify the number and cause of incidental findings detected on positron emission tomography (PET)/CT in patients undergoing investigation for presumed lung cancer.

Methods

The scan reports from PET/CT studies performed for patients with lung cancer under National Institute for Clinical Evidence guidelines from January 2006 until March 2008 were retrospectively reviewed. Incidental findings were followed up by a combination of case note review, clinician feedback, colonoscopy database, histopathology and follow-up imaging.

Results

818 patients were investigated for lung cancer in the study period. 197 incidental findings were found in 175 (21%) patients. The subsequent investigation of 108 lesions confirmed a pathological correlation in 71 (66%) cases. A second primary malignancy was found in 10 patients within the bowel (6), breast (2), tongue (1) and stomach (1). A pre-malignant lesion was confirmed in 25 cases (24 large bowel tubulovillous adenomas and a follicular thyroid lesion). A further 41 (5%) benign abnormalities were detected at multiple sites; the thyroid gland was the single most frequently affected site (14 abnormalities). There were 36 (4.4%) false-positive reported findings, including 17 in the region of the pharynx and larynx and 12 within the large bowel.

Conclusions

Overall, 9.2% of patients with suspected or known lung cancer having PET/CT had a confirmed incidental finding. A malignant or pre-malignant lesion was found in 1.2% and 3.0%, respectively. These were mostly located within the gastrointestinal tract. The majority of false-positive incidental findings were located in the larynx and pharynx. Uptake in these regions is unlikely to be significant in the absence of a CT morphological correlation.The Department of Health and National Institute of Clinical Excellence (NICE) guidelines advise that 18-fludeoxyglucose (FDG) positron emission tomography (PET) should be used to differentiate between benign and malignant lung lesions where anatomical imaging or biopsy are inconclusive or biopsy is contraindicated and for staging of non-small cell lung cancer prior to radical treatment [1,2]. The PET/CT North Scheme is a 5-year UK government-awarded contract whose key objective is to provide an improved diagnosis for cancer patients leading to improvements in quality of care in the north of England. This is expected to generate approximately 48 000 National Health Service (NHS) PET/CT scans over the lifetime of the contract and to assist in the integration of a new diagnostic speciality in the UK [3]. During routine reporting of PET/CT scans, it is common to find areas of increased FDG uptake that are unlikely to be related to the neoplasm for which the patient is being scanned [4-13]. These findings cause delays in the management of the primary malignancy because they require further investigation. Therefore, incidental findings tend to be unpopular with the referring clinicians.The aims of this study were to assess the frequency and significance of incidental findings reported on PET/CT scans in patients investigated for lung cancer to gain insight into the relevance of these findings, to reassure referring clinicians and to improve reporting accuracy.