Thermal ablation therapies in patients with breast cancer liver metastases: A review

Background

The liver is involved in about half of patients with metastatic breast cancer. Unfortunately systemic chemotherapy as the treatment of choice is limited. Due to multifocality and/or insufficient remnant liver volume, the majority of liver metastases are also unresectable. Currently, thermal ablations are used in these patients with acceptable impact.

Methods

We reviewed studies on radiofrequency ablation (RFA), laser-induced thermotherapy (LITT) and microwave ablation (MWA) regarding local tumour response, progression and survival indexes in patients with breast cancer liver metastases (BCLM).

Results

The reviewed literature showed positive response rates of 63 % to 97 % in RF-ablated lesions, 98.2 % in LITT-treated lesions and 34.5–62.5 % in MW-ablated lesions. Median survival was 10.9–60 months using RFA, 51–54 months after LITT and 41.8 months using MWA. Five-year survival rates were 27–30 %, 35 % and 29 %, respectively. Local tumour progression ranged from 13.5 % to 58 % using RFA, 2.9 % with LITT and 9.6 % with MWA.

Conclusion

The reviewed literature demonstrated that ablation therapies either as single therapy or combined with other locoregional therapies are a good alternative as an adjunction to resection in patients with resectable lesions or with positive response using chemotherapy. However, multicentre randomised studies should be conducted to obtain further evidence of the benefits of these treatments in patients with BCLM.

Key points

? Thermal ablation is an alternative treatment for hepatic metastases from breast cancer ? This review assesses thermal ablation therapies and local chemoembolisation techniques ? It helps prioritise treatment options for managing hepatic metastases from breast cancer     

Percutaneous Microwave versus Radiofrequency Ablation of Colorectal Liver Metastases: Ablation with Clear Margins (A0) Provides the Best Local Tumor Control

Purpose

To identify and compare predictors of local tumor progression (LTP)-free survival (LTPFS) after radiofrequency (RF) ablation and microwave (MW) ablation of colorectal liver metastases (CLMs).

Recurrent hepatocellular carcinoma: percutaneous radiofrequency ablation after hepatectomy

PURPOSE: To evaluate the therapeutic efficacy and safety of percutaneous radiofrequency (RF) ablation for recurrent hepatocellular carcinoma (HCC) in the liver after hepatectomy. MATERIALS AND METHODS: Forty-five patients with 53 recurrent HCC tumors in the liver underwent percutaneous RF ablation with ultrasonographic guidance. All patients had a history of hepatic resection for HCC. The mean diameter of recurrent tumors was 2.1 cm (range, 0.8-4.0 cm). All patients were followed up for at least 10 months after ablation (range, 10-40 months; mean, 23 months). Therapeutic efficacy and complications were evaluated with multiphase helical computed tomography (CT) at regular follow-up visits. Overall and disease-free survival rates were calculated. RESULTS: At follow-up CT after initial RF ablation, 11 (21%) of 53 ablated HCC tumor sites showed residual tumor or local tumor progression. After additional RF ablation, complete ablation of 46 (87%) of 53 tumors was attained. Also at initial follow-up CT, before either additional RF ablation or other treatment was performed, 21 (47%) of 45 patients were found to have 41 new HCC tumors at other liver sites. Of these, nine tumors in eight patients were treatable with a second application of RF ablation. Overall survival rates at 1, 2, and 3 years were 82%, 72%, and 54%, respectively. No deaths or complications requiring further treatment occurred as a result of RF ablation. CONCLUSION: Percutaneous RF ablation is an effective and safe method for treating recurrent HCC in the liver after hepatectomy, with a good overall patient survival rate.     

Hepatocellular carcinoma treated with percutaneous radio-frequency ablation: evaluation with follow-up multiphase helical CT.

PURPOSE: To determine serial changes in hepatocellular carcinomas (HCCs) treated with percutaneous radio-frequency (RF) ablation at long-term follow-up multiphase helical computed tomography (CT). MATERIALS AND METHODS: There were 43 nodular HCCs in 40 patients at follow-up CT performed not less than 12 months after RF ablation. All patients underwent follow-up multiphase helical CT immediately, 1 month, and then every 3 months after percutaneous RF ablation. The serial changes in attenuation, enhancement pattern, shape, other findings, and volume of the ablated lesions were analyzed at follow-up CT. RESULTS: Thirty-eight (88%) of 43 ablated lesions were of low attenuation, with absence of contrast material enhancement at immediate and 1-month follow-up CT, which is suggestive of successful treatment. The remaining five lesions (12%) showed peripheral nodular enhancement, suggesting residual viable tumor. Compared with volume changes at immediate follow-up CT, the mean percentages of volume change at 1, 4, 10, 16, and 19 months were 79%, 50%, 27%, 11%, and 6%, respectively. Of 43 ablated lesions, 24 (56%) were mostly round at immediate CT and remained unchanged at subsequent follow-up CT. Peripheral rim enhancement was seen in 34 (79%) of 43 lesions at immediate CT but resolved in all 34 lesions at 1-month follow-up CT. Other associated findings included iatrogenic arteriovenous shunt in 10 patients, perihepatic hemorrhage in three, and pneumothorax in one. CONCLUSION: Follow-up multiphase helical CT of HCCs treated with percutaneous RF ablation showed variable findings in the treated lesions and surrounding liver parenchyma.     

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.     

Contrast-enhanced US-guided Radiofrequency Ablation of Hepatocellular Carcinoma

PurposeContrast-enhanced ultrasound (US) has been shown to be an efficient imaging modality in guiding radiofrequency (RF) ablation of hepatocellular carcinomas (HCC). The purpose of the present study was to assess the usefulness of contrast-enhanced US in guiding RF ablation in patients with early-stage HCC that was not clearly visible on grayscale US or noncontrast computed tomography (CT).Materials and MethodsDuring a 17-month period, contrast-enhanced US–guided RF ablation was performed in 14 patients with 19 early-stage lesions that were poorly defined on grayscale US and noncontrast CT. Contrast-enhanced US was repeated after 30 minutes, and complete ablation was defined as absence of any arterial-phase enhancement within the ablated lesion. Patients were followed periodically with clinical evaluation, liver function tests, α-fetoprotein measurement, and multiphasic CT or magnetic resonance (MR) imaging for a minimum of 1 year after ablation to look for local recurrence or disease progression. Survival probability was estimated with the Kaplan–Meier method.ResultsComplete tumor ablation was achieved in all 19 lesions, with no evidence of residual or recurrent tumor in the ablated areas after a mean follow-up of 16 months. No major complications were observed in any patient. However, new lesions developed in other parts of the liver on follow-up scans in three patients, and were accordingly treated with RF ablation. Two patients died of disease progression or liver failure within the 1-year follow-up.ConclusionsFor early-stage HCCs not well visualized on unenhanced US or CT, contrast-enhanced US provides an additional tool to guide RF ablation.     

Transcatheter CT Hepatic Arteriography Compared with Conventional CT Fluoroscopy Guidance in Percutaneous Thermal Ablation to Treat Colorectal Liver Metastases: A Single-Center Comparative Analysis of 2 Historical Cohorts

PurposeTo evaluate safety and efficacy of CT hepatic arteriography compared with conventional CT fluoroscopy guidance in percutaneous radiofrequency (RF) and microwave (MW) ablation to treat colorectal liver metastases (CRLM).Materials and MethodsThis single-center comparative, retrospective study analyzed data of 108 patients treated with 156 percutaneous ablation procedures (42 CT fluoroscopy guidance [25 RF ablation, 17 MW ablation]; 114 CT hepatic arteriography guidance [18 RF ablation, 96 MW ablation]) for 260 CRLM between January 2009 and May 2019. Local tumor progression-free survival (LTPFS) was assessed using univariate and multivariate Cox proportional hazard regression analyses. LTPFS and overall survival (OS) were estimated using the Kaplan-Meier method.ResultsThere were no complications related to the transarterial catheter procedure. CT hepatic arteriography proved superior to CT fluoroscopy regarding 2-year LTPFS (18/202 [8.9%] vs 19/58 [32.8%]; P < .001, respectively). CT hepatic arteriography versus CT fluoroscopy (hazard ratio = 0.28; 95% confidence interval, 0.15–0.54; P < .001) and MW ablation versus RF ablation (hazard ratio = 0.52; 95% confidence interval, 0.24–1.12; P = .094) were positive predictors for longer LTPFS. Multivariate analysis revealed that CT hepatic arteriography versus CT fluoroscopy (hazard ratio = 0.41; 95% confidence interval, 0.19–0.90; P = .025) was associated with a significantly superior LTPFS. OS was similar between the 2 cohorts (P = .3).ConclusionsWhile adding procedure time and marginal patient burden, transcatheter CT hepatic arteriography–guided ablation was associated with increased local disease control and superior LTPFS compared with conventional CT fluoroscopy. CT hepatic arteriography represents a safe and valid alternative to CT fluoroscopy, as it reduces the number of repeat ablations required without adding risk or detrimental effect on survival.     

Five-year survival following radiofrequency ablation of small, solitary, hepatic colorectal metastases

PURPOSE: Radiofrequency (RF) ablation is an increasingly accepted treatment for nonsurgical candidates with a limited number of colorectal hepatic metastases. RF ablation is most effective in tumors smaller than 4.0 cm. This report describes 5-year survival in patients with single tumors with a maximum diameter of 4 cm. MATERIALS AND METHODS: Forty of 291 patients (14%; 24 men, 16 women; mean age, 67 years; age range, 34-86 y) with no or treated extrahepatic disease were identified who were not candidates for resection and who had a minimum follow-up of 6 months. Sixteen had undergone hepatic resection and two had undergone lung resection and lung ablation. Thirty-two (80%) received chemotherapy. Thirty-five were treated under general anesthesia and five under conscious sedation. Our standard ablation protocol used internally water-cooled electrodes introduced percutaneously with ultrasonography and computed tomography guidance and monitoring. Follow-up data were obtained from primary care physicians or oncologists. RESULTS: Mean tumor diameter was 2.3 cm (range, 0.8-4.0 cm). There were two successfully treated systemic complications: a chest infection and an exacerbation of asthma. There were no local complications. Mean follow-up was 38 months (range, 6-132 months). The median survival duration and 1-, 3-, and 5-year survival rates were 59 months and 97%, 84%, 40%, respectively, after ablation; and 63 months, 100%, 88%, and 54%, respectively, from the diagnosis of liver metastases. History of liver resection did not impact survival. CONCLUSIONS: RF ablation of solitary liver metastases 4 cm or smaller can be performed with minimal morbidity and results in excellent long-term survival, approaching that of surgical resection, even in patients who are not surgical candidates.     

Ultrasound-guided percutaneous thermal ablation of hepatocellular carcinoma using microwave and radiofrequency ablation

AIM: To investigate the therapeutic efficacy of thermal ablation for treatment of hepatocellular carcinoma (HCC) using microwave and radiofrequency (RF) energy application. MATERIALS AND METHODS: A total of 190 nodules in 97 patients (84 male, 13 female; mean age 53.4 years, range 24-74 years) with HCC were treated with microwave or RF ablation in the last 4 years. The applicators were introduced into the tumours under conscious analgesic sedation by intravenous administration of fentanyl citrate and droperidol and local anaesthesia in both thermal ablation procedures. The patients were then followed up with contrast-enhanced computed tomography (CT) to evaluate treatment response. Survival was analysed using the Kaplan-Meier method. RESULTS: Complete ablation was obtained in 92.6% (176/190) nodules. The complete ablation rates were 94.6% (106/112) in microwave ablation and 89.7% (70/78) in RF ablation. The complete ablation rates in tumours/=4.0 cm were 93.1, 93.8 and 86.4%, respectively. Local recurrence was found in 9.5% nodules and the rates in tumours/=4.0 cm in diameter were 3.4, 9.9 and 31.8%, respectively. In the follow-up period, 7.1% nodules ablated by microwave and 12.8% by RF presented local recurrence. The 1, 2 and 3-year distant recurrence-free survivals were 47.2, 34.9 and 31.0%, respectively. Estimated mean survival was 32 months, and 1, 2 and 3-year cumulative survivals were 75.6, 58.5, and 50.0%, respectively. One and 2 years survivals of Child-Pugh class A, B and C patients were 83.8 and 70.4%, 78.2 and 53.2%, 36.3 and 27.3%, respectively. CONCLUSION: Thermal ablation therapy by means of microwave and RF energy application is an effective and safe therapeutic technique for hepatocellular carcinoma. Large tumours can be completely ablated, but have a significantly higher risk of local recurrence at follow-up.     

Risk factors for occurrence of local tumor progression after percutaneous radiofrequency ablation for lung neoplasms

PURPOSE: To examine the characteristics of lung tumors for which radiofrequency (RF) ablation therapy is effective, and to determine what RF ablation parameters are effective for obtaining complete coagulation of the entire ablation zone with a single RF ablation session. MATERIALS AND METHODS: Computed tomography (CT)-guided RF ablation of lung tumors was performed on 82 lesions in 34 patients between April 2003 and May 2005. Tumor characteristics and ablation parameters, including tumor size, location, and depth, and ablation duration, power deployed during ablation, and temperatures achieved were analyzed with regard to local tumor progression. RESULTS: In all, 103 RF ablation sessions were performed on 82 tumors. As a procedure-related complication, pneumothorax occurred in 27 procedures. During the mean follow-up period of 10 months (range, 6-28 months), local tumor progression occurred in 18 (22.0%) of the 82 ablated tumors (3 months after RF ablation in 10, 6 months after RF ablation in 5, 9 months after RF ablation in 1, and 12 months after RF ablation in 2). Mean local progression-free duration was 8.7 +/- 4.5 months (range, 3-28 months). The frequency of local tumor progression was significantly correlated with size, whereas other variables had no statistical association. In tumors with a diameter > or =2.5 cm, only the period of ablation during the initial session was significantly correlated with subsequent local tumor progression (P = 0.000002, chi-square test). CONCLUSION: A long duration of RF ablation is desirable for large lung tumors. The success of RF ablation is dependent upon tumor size. RF ablation treatment is most effective for lesions < 2.5 cm.     

Radiofrequency ablation of small liver malignancies under magnetic resonance guidance: progress in targeting and preliminary observations with temperature monitoring

Objectives

To evaluate the feasibility and effectiveness of magnetic resonance (MR)-guided radiofrequency (RF) ablation for small liver tumours with poor conspicuity on both contrast-enhanced ultrasonography (US) and computed tomography (CT), using fast navigation and temperature monitoring.

Methods

Sixteen malignant liver nodules (long-axis diameter, 0.6–2.4 cm) were treated with multipolar RF ablation on a 1.5-T wide-bore MR system in ten patients. Targeting was performed interactively, using a fast steady-state free precession sequence. Real-time MR-based temperature mapping was performed, using gradient echo–echo planar imaging (GRE-EPI) and hardware filtering. MR-specific treatment data were recorded. The mean follow-up time was 19?±?7 months.

Results

Correct placement of RF electrodes was obtained in all procedures (image update, <500 ms; mean targeting time, 21?±?11 min). MR thermometry was available for 14 of 16 nodules (88%) with an accuracy of 1.6°C in a non-heated region. No correlation was found between the size of the lethal thermal dose and the ablation zone at follow-up imaging. The primary and secondary effectiveness rates were 100% and 91%, respectively.

Conclusions

RF ablation of small liver tumours can be planned, targeted, monitored and controlled with MR imaging within acceptable procedure times. Temperature mapping is technically feasible, but the clinical benefit remains to be proven.     

Percutaneous radio-frequency ablation of hepatic metastases from colorectal cancer: long-term results in 117 patients

PURPOSE: To describe the results of an ongoing radio-frequency (RF) ablation study in patients with hepatic metastases from colorectal carcinoma. MATERIALS AND METHODS: In 117 patients, 179 metachronous colorectal carcinoma hepatic metastases (0.9-9.6 cm in diameter) were treated with RF ablation by using 17-gauge internally cooled electrodes. Computed tomographic follow-up was performed every 4-6 months. Recurrent tumors were retreated when feasible. Time to new metastases and death for each patient and time to local recurrence for individual lesions were modeled with Kaplan-Meier analysis. Modeling determined the effect of number of metastases on the time to new metastases and death and effect of tumor size on local recurrence. RESULTS: Estimated median survival was 36 months (95% CI; 28, 52 months). Estimated 1, 2, and 3-year survival rates were 93%, 69%, and 46%, respectively. Survival was not significantly related to number of metastases treated. In 77 (66%) of 117 patients, new metastases were observed at follow-up. Estimated median time until new metastases was 12 months (95% CI; 10, 18 months). Percentages of patients with no new metastases after initial treatment at 1 and 2 years were 49% and 35%, respectively. Time to new metastases was not significantly related to number of metastases. Seventy (39%) of 179 lesions developed local recurrence after treatment. Of these, 54 were observed by 6 months and 67 by 1 year. No local recurrence was observed after 18 months. Frequency and time to local recurrence were related to lesion size (P < or =.001). CONCLUSION: RF ablation is an effective method to treat hepatic metastases from colorectal carcinoma.     

Therapeutic response assessment of percutaneous radiofrequency ablation for hepatocellular carcinoma: utility of contrast-enhanced agent detection imaging

PURPOSE: To assess the utility of contrast-enhanced agent detection imaging (ADI) in the assessment of the therapeutic response to percutaneous radiofrequency (RF) ablation in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Ninety patients with a total of 97 nodular HCCs (mean, 2.1+/-1.3 cm; range, 1.0-5.0 cm) treated with percutaneous RF ablation under the ultrasound guidance were evaluated with contrast-enhanced ADI after receiving an intravenous bolus injection of a microbubble contrast agent (SH U 508A). We obtained serial contrast-enhanced ADI images during the time period from 15 to 90 s after the initiation of the bolus contrast injection. All of the patients underwent a follow-up four-phase helical CT at 1 month after RF ablation, which was then repeated at 2-4 month intervals during a period of at least 12 months. The results of the contrast-enhanced ADI were compared with those of the follow-up CT in terms of the presence or absence of residual unablated tumor and local tumor progression in the treated lesions. RESULTS: On contrast-enhanced ADI, technical success was obtained in 94 (97%) of the 97 HCCs, while residual unablated tumors were found in three HCCs (3%). Two of the three tumors that were suspicious (was not proven) for incomplete ablation were subjected to additional RF ablation. The remaining one enhancing lesion that was suspicious of a residual tumor on contrast-enhanced ADI was revealed to be reactive hyperemia at the 1-month follow-up CT. Therefore; the diagnostic concordance between the contrast-enhanced ADI and 1-month follow-up CT was 99%. Of the 94 ablated HCCs without residual tumors on both the contrast-enhanced ADI and 1-month follow-up CT after the initial RF ablation, five (5%) had CT findings of local tumor progression at a subsequent follow-up CT. CONCLUSION: Despite its limitations in predicting local tumor progression in the treated tumors, contrast-enhanced ADI is potentially useful for evaluating the early therapeutic effect of percutaneous RF ablation for HCCs.     

MR-guided radiofrequency ablation using a wide-bore 1.5-T MR system: clinical results of 213 treated liver lesions

Objective

To evaluate the technical effectiveness, technical success and patient safety of MR-guided radiofrequency (RF) ablation of liver malignancies using a wide-bore 1.5-T MR system.

Methods

In 110 patients, 56 primary liver lesions and 157 liver metastases were treated in 157 sessions using percutaneous RF ablation. Mean lesion diameter was 20?mm (range 4–54?mm). All planning, procedural and post-interventional control MR investigations were carried out using a wide-bore 1.5-T MR system. Technical success was assessed by a contrast-enhanced MR liver examination immediately after the intervention. Technique effectiveness was assessed by dynamic hepatic MR study 1?month post ablation; mean follow-up period was 24.2?months (range 5–44).

Results

Technical success and technique effectiveness were achieved in 210/213 lesions (98.6?%). In 18/210 lesions (8.6?%), local tumour progression occurred 4–28?months after therapy. Seven of these 18 lesions were treated in a second session achieving complete ablation, 6 other lesions were referred to surgery. Overall RF effectiveness rate was 199/213 (93.4?%); overall therapy success (including surgery) was 205/213 (96.2?%). Two major complications (1.3?%) (bleeding and infected biloma) and 14 (8.9?%) minor complications occurred subsequent to 157 interventions.

Conclusion

Wide-bore MR-guided RF ablation is a safe and effective treatment option for liver lesions.

Key Points

? Magnetic resonance-guided radiofrequency ablation offers various options for monitoring therapy. ? All steps of RF ablation carried out in 1.5-T wide-bore system. ? Therapeutic decisions were based on T1-weighted imaging. ? Technical success and technical effectiveness were high. ? Local tumour progression rate was 8.6?% over a 24-month mean follow-up.     

Liver metastases: 3D shape-based analysis of CT scans for detection of local recurrence after radiofrequency ablation

This HIPAA-compliant pilot study had internal review board approval; informed consent was waived. The purpose was to determine retrospectively the diagnostic performance of a computer-aided three-dimensional (3D) analytic tool for assessing local recurrences of liver metastases by quantifying shape changes in ablated tumors on computed tomographic (CT) scans for follow-up of radiofrequency (RF) ablation. Positron emission tomographic and long-term CT follow-up images were reference standards. Fifty-six follow-up CT scans of 12 liver metastases (mean size, 4.0 cm) in nine patients treated with RF ablation were retrospectively analyzed. After the 1st month following RF ablation, the 3D analytic tool helped quantify ablated tumor shape variations and revealed recurrences even in the absence of abnormal enhancement (sensitivity, seven of seven; specificity, three of five). The 3D tool would have revealed a recurrence before it was reported clinically in two patients. Although results are preliminary, a 3D analytic tool based on shape may be useful in assessing RF ablation results.     

MWA Versus RFA for Perivascular and Peribiliary CRLM: A Retrospective Patient- and Lesion-Based Analysis of Two Historical Cohorts

Purpose

To retrospectively analyse the safety and efficacy of radiofrequency ablation (RFA) versus microwave ablation (MWA) in the treatment of unresectable colorectal liver metastases (CRLM) in proximity to large vessels and/or major bile ducts.

Method and Materials

A database search was performed to include patients with unresectable histologically proven and/or ¹⁸F–FDG–PET avid CRLM who were treated with RFA or MWA between January 2001 and September 2014 in a single centre. All lesions that were considered to have a peribiliary and/or perivascular location were included. Univariate logistic regression analysis was performed to assess the distribution of patient, tumour and procedure characteristics. Multivariate logistic regression was used to correct for potential confounders.

Results

Two hundred and forty-three patients with 774 unresectable CRLM were ablated. One hundred and twenty-two patients (78 males; 44 females) had at least one perivascular or peribiliary lesion (n = 199). Primary efficacy rate of RFA was superior to MWA after 3 and 12 months of follow-up (P = 0.010 and P = 0.022); however, after multivariate analysis this difference was non-significant at 12 months (P = 0.078) and vanished after repeat ablations (P = 0.39). More CTCAE grade III complications occurred after MWA versus RFA (18.8 vs. 7.9 %; P = 0.094); biliary complications were especially common after peribiliary MWA (P = 0.002).

Conclusion

For perivascular CRLM, RFA and MWA are both safe treatment options that appear equally effective. For peribiliary CRLM, MWA has a higher complication rate than RFA, with similar efficacy. Based on these results, it is advised to use RFA for lesions in the proximity of major bile ducts.

     

Breast cancer metastases in liver: laser-induced interstitial thermotherapy--local tumor control rate and survival data

PURPOSE: To evaluate the local tumor control rate and survival data for magnetic resonance (MR) imaging-guided laser ablation of breast cancer liver metastases by using laser-induced interstitial thermotherapy (LITT). MATERIALS AND METHODS: MR-guided LITT was performed in 232 female patients with 578 liver metastases from breast cancer. Survival rates were calculated with the Kaplan-Meier method. Indications for the procedure were defined for patients with no more than five metastases, none of which were larger than 5 cm in diameter, as follows: recurrent liver metastases after partial liver resection (8.2%), metastases in both liver lobes (45.2%), locally nonresectable tumors (19%), general contraindications for surgery (2.6%), or refusal to undergo surgical resection (25%). RESULTS: Local recurrence rate at 6-month follow-up after LITT was 2.3% (five of 213) for metastases up to 2 cm in diameter, 4.3% (seven of 162) for metastases 2-3 cm in diameter, 3.2% (two of 63) for metastases 3-4 cm in diameter, and 1.9% (one of 52) for metastases larger than 4 cm in diameter. No additional local tumor progression was observed beyond 6 months. The mean survival rate for all treated patients, with calculation started on the date of diagnosis of the metastases treated with LITT, was 4.9 years (95% confidence interval: 4.3, 5.4). The median survival was 4.3 years; 1-year survival, 96%; 2-year survival, 80%; 3-year survival, 63%; and 5-year survival, 41%. The mean survival after the first LITT treatment was 4.2 years (95% confidence interval: 3.6, 4.8). CONCLUSION: MR-guided LITT yields high local tumor control and survival rates in patients with liver metastases from breast cancer.     

Thermische Ablation von Lebermetastasen: Aktueller Stand und Perspektiven

Purpose. To present thermal ablation of liver metastases via laser induced thermotherapy. Material and methods. Different technical procedures of thermal ablation and online monitoring are used, as there are the MR-guided laser induced thermotherapy (LITT) and the radiofrequency ablaton thermotherapy (RF). Results. In a prospective non randomized study 606 patients with liver metastases were treated via MR-guided laserinduced thermotherapy. Inclusion criteria were the exclusion of extrahepatic tumor spread and a number of metastases lower than 5 and a size lower than 50 mm in diameter. The local tumor control rate in the 3 month and 6 month control study was 98.3%, the complication rate 3,5% (clinically relevant: 1,2%). The mean survival rate was 40,9 months for all patients with liver metastases without statistically relevant differences for various primaries, like colorectal carcinoma, breast cancer and various other tumors. Results for radiofrequency are so far limited with incidence of a higher local tumor recurrence rate versus LITT. Conclusion. MR-guided LITT results in a high local tumor control rate with improved survival.     

Intrahepatic tumor recurrence after partial hepatectomy: value of percutaneous radiofrequency ablation

PURPOSE: To determine the risks and benefits of percutaneous radiofrequency (RF) ablation of recurrent hepatic tumors in patients who have undergone hepatic resection. MATERIALS AND METHODS: Retrospective review of the institutional RF ablation database yielded 35 patients with recurrent hepatic tumor after hepatectomy. Sixty-one recurrent hepatic tumors (mean diameter +/- SD, 1.7 +/- 1.1 cm; range, 0.5-5.3 cm) were ablated percutaneously under sonographic guidance or combined guidance with sonographic and fluoroscopic computed tomography (CT). Follow-up CT, magnetic resonance imaging, or both were used for assessment of the primary and secondary therapeutic effectiveness rate and failure of RF ablation. Patients' survival status was determined by contacting the primary care physician or searching the Social Security Death Index. RESULTS: Complete ablation was accomplished in 54 of 61 hepatic tumors (primary therapeutic effectiveness rate, 88.5%). During a mean follow-up time of 18 months (range, 1-65 months), 14.8% of the tumors (n = 9) were incompletely ablated. Three of the nine incompletely ablated tumors were treated with a second RF ablation, all three of which failed (secondary therapeutic effectiveness rate, 0%). Distant intrahepatic tumor progression appeared in 23 of 35 patients (65.7%). One major complication (2.1%, one of 48 sessions) and eight minor complications (16.7%, eight of 48 sessions) were reported. The major complication was hepatic abscess formation. The overall survival rates for all patients at 1, 2, and 3 years were 76%, 68%, and 45%, respectively. For patients with metastases from colorectal cancer (n = 14), the overall survival rates were 72%, 60%, and 60% at 1, 2, and 3 years, respectively; and for patients with hepatocellular carcinoma (n = 8), the overall survival rates were 72%, 58%, and 44% at 1, 2, and 3 years, respectively. CONCLUSION: Percutaneous RF ablation offers a safe and effective treatment option for recurrent hepatic tumors after previous partial hepatectomy.     

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.