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.     

Liver metastases: interventional therapeutic techniques and results, state of the art

The liver is the most common site of metastatic tumour deposits. Hepatic metastases are the major cause of morbidity and mortality in patients with gastrointestinal carcinomas and other malignant tumours. The rationale and results for interventional therapeutic techniques in the treatment of liver metastases are presented. For the treatment of patients with irresectable liver metastases, alternative local ablative therapeutic modalities have been developed. Technique and results of local interventional therapies are presented such as microwave-, radiofrequency (RF)- and ultrasound ablation, and laser-induced interstitial therapy (LITT), cryotherapy and local drug administration such as alcohol injection, endotumoral chemotherapy and regional chemoembolisation. In addition to cryotherapy, all ablative techniques can be performed percutaneously with low morbidity and mortality. Cryotherapy is an effective and precise technique for inducing tumour necrosis, but it is currently performed via laparotomy. Percutaneous local alcohol injection results in an inhomogeneous distribution in liver metastases with unreliable control rates. Local chemotherapeutic drug instillation and regional chemoembolisation produces relevant but non-reproducible lesions. Laser-induced interstitial thermotherapy (LITT) performed under MRI guidance results in precise and reproducible areas of induced necrosis with a local control of 94 %, and with an improved survival rate. Interventional therapeutic techniques of liver metastases do result in a remarkable local tumour control rate with improved survival results. Received: 29 July 1998; Revision received: 30 October 1998; Accepted: 4 November 1998     

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

PURPOSE: To evaluate the local tumor control and survival data for magnetic resonance (MR) imaging-guided laser-induced interstitial thermotherapy (LITT) of colorectal liver metastases. MATERIALS AND METHODS: MR imaging-guided LITT was performed in 603 patients (mean age, 61.2 years) with 1,801 liver metastases of colorectal cancer. Survival rates were calculated by means of the Kaplan-Meier method. Local tumor control and tumor volume were evaluated with nonenhanced and contrast material-enhanced MR imaging. Indications for the procedure were defined for patients with five or fewer metastases, none of which were larger than 5 cm in diameter. The indications included recurrent liver metastases after partial liver resection in 37.6% of study patients, metastases in both liver lobes in 32.5%, locally nonresectable lesions in 11.3%, general contraindications for surgery in 4.6%, and refusal to undergo surgical resection in 13.9%. RESULTS: Local recurrence rate at 6-month follow-up was 1.9% (nine of 474) for metastases up to 2 cm in diameter, 2.4% (13 of 539) for metastases 2.1-3.0 cm in diameter, 1.2% (four of 327) for metastases 3.1-4.0 cm in diameter, and 4.4% (13 of 294) for metastases larger than 4 cm in diameter. The mean survival rate for all treated patients, with calculation started on the date of diagnosis of the metastases (which were treated with LITT) was 4.4 years (95% CI: 4.0, 4.8) (1-year survival, 94%; 2-year survival, 77%; 3-year survival, 56%; 5-year survival, 37%). Median survival was 3.5 years (95% CI: 3.0, 3.9). Mean survival after the first LITT treatment was 3.8 years (95% CI: 3.4, 4.2). Median survival was 2.9 years (95% CI: 2.4, 3.3). CONCLUSION: MR imaging-guided LITT yields high local tumor control and survival rates in well-selected patients with limited liver metastases of colorectal carcinoma.     

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.     

Adrenal metastases: CT-guided and MR-thermometry-controlled laser-induced interstitial thermotherapy

The aim of the study was to evaluate the feasibility, safety and effectiveness of CT-guided and MR-thermometry-controlled laser-induced interstitial thermotherapy (LITT) in adrenal metastases. Nine patients (seven male, two female; average age 65.0 years; range 58.7–75.0 years) with nine unilateral adrenal metastases (mean diameter 4.3 cm) from primaries comprising colorectal carcinoma (n = 5), renal cell carcinoma (n = 1), oesophageal carcinoma (n = 1), carcinoid (n = 1), and hepatocellular carcinoma (n = 1) underwent CT-guided, MR-thermometry-controlled LITT using a 0.5 T MR unit. LITT was performed with an internally irrigated power laser application system with an Nd:YAG laser. A thermosensitive, fast low-angle shot 2D sequence was used for real-time monitoring. Follow-up studies were performed at 24 h and 3 months and, thereafter, at 6-month intervals (median 14 months). All patients tolerated the procedure well under local anaesthesia. No complications occurred. Average number of laser applicators per tumour: 1.9 (range 1–4); mean applied laser energy 33 kJ (range 15.3–94.6 kJ), mean diameter of the laser-induced coagulation necrosis 4.5 cm (range 2.5–7.5 cm). Complete ablation was achieved in seven lesions, verified by MR imaging; progression was detected in two lesions in the follow-up. The preliminary results suggest that CT-guided, MR-thermometry-controlled LITT is a safe, minimally invasive and promising procedure for treating adrenal metastases.     

Laser-induced interstitial thermotherapy of liver metastases in an interventional 0.5 Tesla MRI system: technique and first clinical experiences

Laser-induced interstitial thermotherapy (LITT) surveyed by magnetic resonance imaging (MRI) has been shown to be effective in various applications. The laser treatment of colorectal liver metastases usually requires a separate device (e.g., ultrasound or CT) to position the laser applicator. In this study, we used an interventional 0.5 T MRI system, allowing both the navigation to the target tissue and on-line thermometry. Laser irradiation was performed using a near-infrared laser source combined with a cooled laser light guide. We treated 20 patients exhibiting a total of 58 colorectal liver metastases. Clinically relevant complications did not occur. No residual tumor was observed after laser irradiation in all metastases with a diameter below 2 cm. Metastases with a mean diameter between 2 and 3 cm demonstrated total necrosis in 71%, while in larger tumors this proportion decreased to 46% (diameter, 3-4 cm) and 30% (diameter, >4 cm), respectively. We conclude that LITT, guided by the employed interventional MRI system, is feasible and safe. The results suggest a more aggressive treatment, especially for larger metastases. J. Magn. Reson. Imaging 2001;13:729-737.     

Phase II Feasibility Study on the Combination of Two Different Regional Treatment Approaches in Patients with Colorectal “Liver-Only” Metastases: Hepatic Interstitial Brachytherapy Plus Regional Chemotherapy

The aim of this study was to evaluate the feasibility, safety, and efficacy of combined treatment with hepatic interstitial brachytherapy (HIB) and hepatic arterial infusion (HAI) of chemotherapy after interventional implantation of port catheter systems. Thirty-three patients with unresectable “liver-only” metastases of colorectal cancer were treated with both HIB and HAI during the course of their disease. All 33 patients had recurrent disease and 27 had received previous chemotherapy. Of these, 15 received HAI first and were then consolidated with HIB, 9 started with HIB and were continued with HAI, and 9 received first HIB and subsequently HAI after hepatic disease progression. Patients were evaluated for treatment characteristics, side effects, and efficacy. Comparisons between treatment groups were also performed. The median tumor diameter of metastases treated with brachytherapy was 4.6 cm (range: 1–12 cm). The median minimal irradiation dose inside the tumor margin was 18 Gy administered to a mean of two metastases in 69 interventions. Minor (n = 4) and major (n = 3) complications occurred in 10% of interventions. WHO grade III adverse events of the regional chemotherapy were observed in seven patients; grade IV, in one patient. At a median follow-up of 28 months (range: 7–74 months), the median time to disease progression after first treatment was 10.5 months (range: 1–35 months). Of 138 metastases treated by brachytherapy, 16 local recurrences were seen (mean, 12.3 months; range, 3–45 months). No signs of hepatic failure were observed in any of our patients. In conclusion, combinations of two minimally invasive therapeutic methods are feasible, with acceptable complication rates, and provide promising results in colorectal cancer patients with unresectable hepatic metastases.     

Laserinduzierte Thermotherapie von Lungenmetastasen und primären Lungentumoren

We present laser-induced thermotherapy (LITT) of primary and secondary lung tumors analysing indications and technical concepts. Thirty patients with lung metastases of different primary tumors (n=24) as well as localized lung tumors (n=6) were prospectively treated in 41 sessions using laser-induced thermotherapy (LITT). An MR-compatible puncture system was used with direct puncture technique. The puncture was performed via CT guidance in care vision technique. Eight patients were thermoablated using MR tomographical monitoring, 22 patients using CT monitoring. Local therapy effects, tumor control rate, side effects, complications, and survival were evaluated. In 74% of cases (28/38 lesions) of 24 patients with lung metastases and in all cases of the 6 patients with lung carcinoma a complete local ablation could be achieved. The complication rate (pneumothorax) was 9,8%. One patient with bronchial carcinoma had to be thoracotomized and resected. 93% of the patients are still alive. Percutaneous LITT of lung tumors permits a complete ablation of lung metastases and lung carcinomas with a low complication rate. Indications for the procedure were defined for patients with no more than 5 metastases up to 3 cm in size.     

Image-guided ablation of painful metastatic bone tumors: a new and effective approach to a difficult problem

Painful skeletal metastases are a common problem in cancer patients. Although external beam radiation therapy is the current standard of care for cancer patients who present with localized bone pain, 20–30% of patients treated with this modality do not experience pain relief, and few further options exist for these patients. For many patients with painful metastatic skeletal disease, analgesics remain the only alternative treatment option. Recently, image-guided percutaneous methods of tumor destruction have proven effective for treatment of this difficult problem. This review describes the application, limitations, and effectiveness of percutaneous ablative methods including ethanol, methyl methacrylate, laser-induced interstitial thermotherapy (LITT), cryoablation, and percutaneous radiofrequency ablation (RFA) for palliation of painful skeletal metastases.     

Reirradiation for Recurrent Neck Metastases of Head-and-Neck Tumors Using CT-Guided Interstitial 192Ir HDR Brachytherapy

PURPOSE: To report the therapeutic results obtained with CT-guided interstitial high-dose-rate brachytherapy (HDR-BRT) as exclusive treatment for recurrent neck metastases of head-and-neck tumors. PATIENTS AND METHODS: Between 1995 and 1999, 49 patients with prior radiation therapy (RT) with or without surgery for primary head-and-neck tumors were treated for recurrent neck metastases located within previously irradiated volumes. All patients had fixed lymphadenopathy with a mean tumor volume of 96 cm(3) (range, 15-452 cm(3)). There were 38 males and eleven females with a mean age of 60 years (range, 28-79 years). All patients had previously received RT as primary or adjuvant treatment with a mean dose of 54 Gy (range, 45-80 Gy). 36 patients (73%) underwent surgery, and 26 (53%) received adjuvant or palliative chemotherapy. The accelerated hyperfractionated interstitial HDR-BRT (2 x 3.0 Gy/day) delivered 30 Gy in 37/49 (75%) and 36 Gy in 12/49 implants (25%). RESULTS: At a minimum 6-week follow-up, the response rate was 83% (41/49) with complete remission in 20% (10/49) and partial remission in 63% (31/49) of the implanted tumor sites. 8/49 patients (17%) did not respond to the treatment. After 19 months of median follow-up, the local control rate was 69% and a total of 15/49 patients (30%) experienced local disease progression. Of these, nine (18%) had locoregional progression and six (12%) progression within the treated volume. The median post-BRT survival was 14 months. The overall survival rate was 52% at 1 year, 31% at 2 years, and 6% at 3 years. CONCLUSION: In patients with recurrent cervical lymphadenopathy of head-and-neck tumors, exclusive interstitial HDR-BRT can provide palliation and tumor control.     

Large-sized hepotocellular carcinoma (HCC): a neoadjuvant treatment protocol with repetitive transarterial chemoembolization (TACE) before percutaneous MR-guided laser-induced thermotherapy (LITT)

This study aims to evaluate the efficacy and safety of a neoadjuvant treatment protocol with repeated transarterial chemoembolization (TACE) before MR-guided laser-induced thermotherapy (LITT) for large-sized hepatocellular carcinomas (HCC). Repeated TACE (mean, 3.5 treatments per patient) was performed in 48 patients with neoadjuvant intention (the largest lesion was between 50 and 80 mm in diameter, and there were no more than five lesions). For the TACE treatment, we used 10 mg/m² mitomycin, 10 ml/m² Lipiodol and microspheres. The tumor volume was measured by MRI. Lipiodol retention of the tumors was evaluated with CT. After the diameter of the tumors had decreased to less than 50 mm, the patients were treated with MR-guided LITT 4 to 6 weeks after embolization. Repeated TACE reduced the tumor size in 32 patients (66.7%), forming the basis for performing MR-guided LITT procedures. These patients received one to four laser treatments (mean, 1.9 per patient) for tumor ablation, resulting in a median survival of 36.0 months after the first treatment. For the remaining patients, no reduction in tumor size was achieved in 12 patients and disease progression in 4 patients. Neoadjuvant TACE appears to be an effective treatment of large-sized HCC, which extends the indication for MR-guided LITT.     

Transacatheter arterial embolization for malignant osseous and soft tissue sarcomas. II. Clinical results

Purpose: To evaluate the clinical effects of transcatheter arterial embolization (TAE) on malignant bone and soft tissue tumors. Methods: TAE was performed in 10 patients with primary bone and soft tissue sarcomas and in 31 patients with metastatic bone tumors. The embolized arteries were the internal iliac artery in 30 cases, the intercostal artery in six cases, the lumbar artery in five cases, the suprascapular artery in three cases, and the iliolumbar artery, the internal pudendal artery, and the lateral sacral artery in one case each. The embolized material was gelatin sponge particles. The chemotherapeutic drugs were usually 20–40 mg of doxorubicin for primary and metastatic tumors and 50–100 mg of cisplatin only for primary tumors. In addition, 50–60 Gy of 10-MV radiotherapy with or without radiofrequency (RF)-capacitive hyperthermia in four sessions was administered before TAE for primary tumors only. Results: Even though the pain score increased immediately after TAE, 30 of 38 (79%) patients with pain (8 of 9 with primary tumors, and 22 of 29 with metastases) achieved pain control after TAE. A necrotic low-density area shown by computed tomography (CT) after TAE was found in 31 of 41 (76%) tumors [8 of 10 (80%) with primary tumors, and 23 of 31 (74%) with metastatic tumors]. The tumor size decreased in 14 of 25 (56%) primary and metastatic tumors after 3 months. Osteosclerotic changes appeared in two cases of metastatic tumors after 6 months. In five tumors resected after TAE, large areas of necrosis within the tumor were confirmed histologically. Transient local pain and numbness appeared after TAE, but were relieved by drug treatment within 1 week. No severe complications except a case of gluteal muscle necrosis were encountered after TAE. The 1-year survival rate of the patients with primary tumors was 38.1%, and the median survival was 18 months. The longest survival was 84 months. The 1-year survival rate of the patients with metastatic bone tumors was 38.9%; the median survival was 12 months. The longest survival was 24 months. Conclusion: TAE could be an effective treatment for pain control and local control of malignant bone and soft-tissue tumors.     

Liver metastases of neuroendocrine carcinomas: interventional treatment via transarterial embolization, chemoembolization and thermal ablation

The aim of this review article is to provide a practical clinical guideline for indication, technical aspects, protocol guideline and strategies for the interventional treatment of liver metastases from neuroendocrine tumors and focusing on the results of various protocols of management. The response to therapy, in the published articles, is calculated on the basis of the following clinical parameters; including symptomatic response (SR), biologic response (BR), morphological response (MR), progress free survival (PFS), and survival periods (SP). Transarterial chemoembolization (TACE) has been associated with SR rates of 60-95%, BR of 50-90%, MR of 33-80%, SR of 20-80 months, and a 5-year survival of between 50% and 65%. PFS was also between 18 and 24 months. In the transarterial embolization (TAE) group, SR was similar to the TACE group, MR was 32% and 82%, survival was between 18 and 88 months with a survival rate of 40-67%, and BR was between 50% and 69%. Radiofrequency ablation (RFA), either percutaneous or during surgery, has been associated with SR of 71-95% for a mean duration of 8-10 months, BR of 65%, and mean SP of 1.6 years after ablation. The mean survival following surgical resection for operable cases is 4.26 years ± S.D.: 1.1.

Conclusion

The interventional protocols for the management of liver metastases from neuroendocrine tumors: for oligonodular liver metastatic deposits, local resection or RFA and/or LITT is recommended, while in multinodular diseases with higher tumor load, TACE or TAE is recommended.     

Assessment of local control after laser-induced thermotherapy of liver metastases from colorectal cancer: contribution of FDG-PET in patients with clinical suspicion of progressive disease

BACKGROUND: Management of patients after locally ablative treatment of liver metastases requires exact information about local control and systemic disease status. To fulfill these requirements, whole-body imaging using positron emission tomography with (18)F-fluorodeoxyglucose (FDG-PET) is a promising alternative to morphologic imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI). PURPOSE: To evaluate FDG-PET for the assessment of local control and systemic disease in patients with clinical suspicion of tumor progression after laser-induced thermotherapy (LITT) of colorectal liver metastases. MATERIAL AND METHODS: In 21 patients with suspicion of progressive disease after LITT, whole-body FDG-PET was performed. The presence of viable tumor within treated lesions, new liver metastases, and extrahepatic disease was evaluated visually and semiquantitatively (maximal standard uptake value [SUV(max)], tumor-to-normal ratio [T/N]). The standard of reference was histopathology (n = 25 lesions) and/or clinical follow-up (>12 months) including contrast-enhanced MRI of the liver. RESULTS: Among 54 metastases treated with LITT, 29 had residual tumor. Receiver operating characteristic (ROC) analysis of SUV(max) (area under the curve (AUC) 0.990) and T/N (AUC 0.968) showed a significant discrimination level of negative or positive lesion status with an equal accuracy of 94% (51/54). The overall accuracy of visual FDG-PET was 96% (52/54), with one false-negative lesion among six examined within 3 days after LITT, and one false-positive lesion examined 54 days after LITT. In the detection of new intra- and extrahepatic lesions, FDG-PET resulted in correct alteration of treatment strategy in 43% of patients (P = 0.007). CONCLUSION: FDG-PET is a promising tool for the assessment of local control and whole-body restaging in patients with clinical suspicion of tumor progression after locally ablative treatment of colorectal liver metastases with LITT.     

Clinical outcome of stereotactic body radiotherapy of 54 Gy in nine fractions for patients with localized lung tumor using a custom-made immobilization system

Purpose The aim of this study was to investigate the clinical outcome of stereotactic body radiotherapy (SBRT) of 54 Gy in nine fractions for patients with localized lung tumor using a custom-made immobilization system. Methods and materials The subjects were 19 patients who had localized lung tumor (11 primaries, 8 metastases) between May 2003 and October 2005. Treatment was conducted on 19 lung tumors by fixed multiple noncoplanar conformal beams with a standard linear accelerator. The isocentric dose was 54 Gy in nine fractions. The median overall treatment time was 15 days (range 11–22 days). All patients were immobilized by a thermo-shell and a custom-made headrest during the treatment. Results The crude local tumor control rate was 95% during the follow-up of 9.4–39.5 (median 17.7) months. In-field recurrence was noted in only one patient at the last follow-up. The Kaplan-Meier overall survival rate at 2 years was 89.5%. Grade 1 radiation pneumonia and grade 1 radiation fibrosis were observed in 12 of the 19 patients. Treatment-related severe early and late complications were not observed in this series. Conclusion The stereotactic body radiotherapy of 54 Gy in nine fractions achieved acceptable tumor control without any severe complications. The results suggest that SBRT can be one of the alternatives for patients with localized lung tumors. Part of this work was presented at the 65th annual meeting of the Japan Radiological Society, April 2006     

Liver metastases of neuroendocrine carcinomas: Interventional treatment via transarterial embolization,chemoembolization and thermal ablation

The aim of this review article is to provide a practical clinical guideline for indication, technical aspects, protocol guideline and strategies for the interventional treatment of liver metastases from neuroendocrine tumors and focusing on the results of various protocols of management. The response to therapy, in the published articles, is calculated on the basis of the following clinical parameters; including symptomatic response (SR), biologic response (BR), morphological response (MR), progress free survival (PFS), and survival periods (SP). Transarterial chemoembolization (TACE) has been associated with SR rates of 60–95%, BR of 50–90%, MR of 33–80%, SR of 20–80 months, and a 5-year survival of between 50% and 65%. PFS was also between 18 and 24 months. In the transarterial embolization (TAE) group, SR was similar to the TACE group, MR was 32% and 82%, survival was between 18 and 88 months with a survival rate of 40–67%, and BR was between 50% and 69%. Radiofrequency ablation (RFA), either percutaneous or during surgery, has been associated with SR of 71–95% for a mean duration of 8–10 months, BR of 65%, and mean SP of 1.6 years after ablation. The mean survival following surgical resection for operable cases is 4.26 years ± S.D.: 1.1.ConclusionThe interventional protocols for the management of liver metastases from neuroendocrine tumors: for oligonodular liver metastatic deposits, local resection or RFA and/or LITT is recommended, while in multinodular diseases with higher tumor load, TACE or TAE is recommended.     

Preliminary clinical experience with laser-induced interstitial thermotherapy in patients with hepatocellular carcinoma

The purpose of this preliminary study was to evaluate whether laser-induced interstitial thermotherapy (LITT) may be used for palliative treatment of localized hepatocellular carcinomas (HCC). We applied LITT to two patients suffering from unresectable localized hepatocellular carcinomas of different sizes (2.5 and 4 cm). LITT was performed with an Nd:YAG laser (1,064 nm) at 5 W laser power (15–20 minutes). Thermometry during LITT was performed by MRI using a temperature-sensitive T1-weighted fast low-angle shot (FLASH) sequence. Follow-up for local tumor control was performed by MRI and ultrasound. LITT was well tolerated and no adverse events occurred during or after LITT; no secondary liver lesions were seen in the follow-up (11 or 12 months, respectively). Only minimal tumor growth was observed in the larger HCC (from 4 to 5 cm), whereas the smaller HCC remained unchanged in size during 11 months of follow-up. We conclude that LITT might be an effective minimally invasive palliative treatment option for patients with small unresectable HCC.     

MR-guided laser thermoablation of inoperable renal tumors in an open-configuration interventional MR scanner: preliminary clinical experience in three cases.

A minimally invasive technique for performing magnetic resonance (MR)-guided laser interstitial thermoablation (LITT) for inoperable renal tumors is described. Three patients were treated using a percutaneous technique with real-time MR guidance in an open access interventional MR scanner. Laser therapy was delivered using a neodymium-YAG source via a water-cooled applicator system. Thermal lesions were monitored in real time using a color thermometry sequence. All patients were discharged the following day with no complications. Follow-up with gadolinium-enhanced MRI in a conventional high-field system confirmed necrosis in targeted tissue, and further treatment is planned for one patient. We concluded that LITT can be useful in treating inoperable renal malignancy and merits further evaluation. J. Magn. Reson. Imaging 1999;10:545-549.     

CT-guided interstitial brachytherapy in the local treatment of extrahepatic, extrapulmonary secondary malignancies

The purpose was to evaluate the safety and efficacy of high-dose-rate (HDR) CT-guided interstitial brachytherapy in the treatment of extrahepatic, extrapulmonary, secondary malignancies. Nineteen patients were included in this prospective study. The median age was 66 years (49–77). Underlying primaries comprised colorectal carcinomas in six, renal cell carcinoma in three, pancreatic carcinoma in three, cervical cancer in two, endometrial cancer in two and NSCLC, breast cancer and sarcoma in one patient each. All patients had undergone extensive pretreatments. CT-guided HDR brachytherapy employed a ¹⁹²Iridium source. Dose planning for brachytherapy was performed using 3D CT data acquired after CT-guided percutaneous applicator positioning. MRI follow-up was performed 6 weeks and every 3 months post intervention. Primary endpoints were complications, local tumor control and progression-free survival. The median tumor diameter was 6 cm (2–15 cm). Tumor locations included the hepatoduodenal ligament, mesentery, adrenal gland, mesogastrium and local recurrences after rectal or pancreatic cancer. The minimal median dose in the target volume was 11 Gy (4–18 Gy). Minor complications comprised pain and fever (n=6, 32%). Major complications included one hospital death of unknown causes (n=1; 5%). Median follow-up was 7 months (1–16). Four patients (21%) died during the follow-up period. Local tumor control was 76.5% after 6 months and progression-free survival 47% after 6 months. Minimally invasive CT-guided HDR brachytherapy is safe and effective in the palliative treatment of extrahepatic, extrapulmonary secondary malignancies.     

MR imaging-guided interstitial photodynamic laser therapy for advanced head and neck tumors

Photodynamic therapy (PDT) is a site-specific tumor treatment involving the administration of a photosensitizer activated by the local application of light. In interstitial PDT (IPDT), multiple laser fibers are inserted into the depth of the tumor. Image guidance is essential for accurate, safe, and uniform light delivery. We report a novel technique of IPDT for advanced head and neck tumors involving an open interventional MR system. Initial results are encouraging, with minimal procedural morbidity, successful palliation of symptoms, and prolongation of expected survival time.