Stereotactic Radiofrequency Ablation for Breast Cancer Liver Metastases

Purpose

To evaluate outcomes in patients with liver metastases from breast cancer treated with stereotactic radiofrequency (RF) ablation.

Transpulmonary CT-Guided Radiofrequency Ablation of Liver Metastasis

The percutaneous approach for RF ablation of liver lesions high up in the dome is always difficult. The authors describe a transpulmonary approach that may be simpler and safer to use.     

Stereotactic Radiofrequency Ablation for Metastatic Melanoma to the Liver

Purpose

To evaluate the outcome of patients with melanoma liver metastasis treated with stereotactic radiofrequency ablation (SRFA).

Material and Method

Following IRB approval, a retrospective evaluation of the treatment of 20 patients with 75 melanoma liver metastases was performed.

Results

A median number of 2 lesions (range 1–14) per patient with a median size of 1.7 cm (range 0.5–14.5 cm) were treated. 67 lesions were <3 cm (89.3 %) and 8 lesions were >3 cm (10.7 %). Per patient a median of 1 ablation session was performed (range: 1–4) totaling 34 sessions. There were no procedure-related deaths and all major complications (n = 3) could be easily treated by pleural drainages. The primary and secondary success rates were 89.3 and 93.3 %, respectively. The overall local recurrence rate was 13.3 %. Four of ten local recurrences were re-treated successfully by SRFA. During follow-up, 9/20 patients developed extrahepatic metastatic disease and 10/20 had liver recurrence at any location. The median OS from the date of SRFA was 19.3 months, with an OS of 64, 41, and 17 % at 1, 3, and 5 years, with no significant difference for patients with cutaneous and ocular melanoma. The median DFS after SRFA for all 20 patients was 9.5 months, with 37, 9, and 0 % at 1, 3, and 5 years.

Conclusions

Due to the high local curative potential and the promising long-term survival rates associated with minimal morbidity and mortality, radiofrequency ablation seems to be an attractive alternative to resection in patients with melanoma liver metastases.

     

Radiofrequency Ablation for Liver Metastasis from Gastrointestinal Stromal Tumor

PurposeTo evaluate the feasibility, safety, and clinical outcomes of radiofrequency (RF) ablation for the treatment of liver metastases from gastrointestinal stromal tumor (GIST).Materials and MethodsSeven consecutive patients with 21 GIST liver metastases received RF ablation under computed tomographic (CT) fluoroscopic guidance. Liver metastases were solitary in two patients and multiple in five patients, with a mean maximum tumor diameter of 2.2 cm±1.1 (range, 1.2–4.2 cm). In addition to feasibility and safety, local tumor progression and overall and GIST-related survival associated with RF ablation were assessed.ResultsAll liver metastases were treated in 12 RF sessions, after which contrast-enhanced CT showed disappearance of tumor enhancement. No RF procedure-related complications occurred. Local tumor progression developed in one tumor (4.8%) during the mean follow-up period of 30.6 months±27.5 (range, 5.9–76.4 mo). New liver metastasis in untreated liver and lung metastasis developed in one patient each. One patient died of subarachnoid hemorrhage 5.9 months after RF ablation, but no GIST-related deaths occurred. The respective overall and GIST-related survival rates were 85.7% (95% confidence interval, 33.6%–97.8%) and 100% at 1, 3, and 5 years.ConclusionsRF ablation is a feasible, safe, and useful therapeutic option for the treatment for GIST liver metastases.     

Comparison of Wet Radiofrequency Ablation with Dry Radiofrequency Ablation and Radiofrequency Ablation Using Hypertonic Saline Preinjection: Ex Vivo Bovine Liver

Objective

We wished to compare the in-vitro efficiency of wet radiofrequency (RF) ablation with the efficiency of dry RF ablation and RF ablation with preinjection of NaCl solutions using excised bovine liver.

Materials and Methods

Radiofrequency was applied to excised bovine livers in a monopolar mode for 10 minutes using a 200 W generator and a perfused-cooled electrode with or without injection or slow infusion of NaCl solutions. After placing the perfused-cooled electrode in the explanted liver, 50 ablation zones were created with five different regimens: group A; standard dry RF ablation, group B; RF ablation with 11 mL of 5% NaCl solution preinjection, group C; RF ablation with infusion of 11 mL of 5% NaCl solution at a rate of 1 mL/min, group D; RFA with 6 mL of 36% NaCl solution preinjection, group E; RF ablation with infusion of 6 mL of 36% NaCl solution at a rate of 0.5 mL/min. In groups C and E, infusion of the NaCl solutions was started 1 min before RF ablation and then maintained during RF ablation (wet RF ablation). During RF ablation, we measured the tissue temperature at 15 mm from the electrode. The dimensions of the ablation zones and changes in impedance, current and liver temperature during RF ablation were then compared between the groups.

Results

With injection or infusion of NaCl solutions, the mean initial tissue impedance prior to RF ablation was significantly less in groups B, C, D, and E (43-75 Ω) than for group A (80 Ω) (p < 0.05). During RF ablation, the tissue impedance was well controlled in groups C and E, but it was often rapidly increased to more than 200 Ω in groups A and B. In group D, the impedance was well controlled in six of ten trials but it was increased in four trials (40%) 7 min after starting RF ablation. As consequences, the mean current was higher for groups C, D, and E than for the other groups: 401 ± 145 mA in group A, 287 ± 32 mA in group B, 1907 ± 96 mA in group C, 1649 ± 514 mA in group D, and 1968 ± 108 mA in group E (p < 0.05). In addition, the volumes of RF-induced coagulation necrosis were greater in groups C and E than in group D, which was greater than in groups A and B than in group E (p < 0.05); 14.3 ± 3.0 cm³ in group A; 12.4 ± 3.8 cm³ in group B; 80.9 ± 9.9 cm³ in group C; 45.3 ± 11.3 cm³ in group D and 81.6 ± 8.6 cm³ in group E. The tissue temperature measured at 15 mm from the electrode was higher in groups C, D and E than other groups (p < 0.05): 53 ± 12℃ in group A, 42 ± 2℃ in group B, 93 ± 8℃ in group C; 79 ± 12℃ in group D and 83 ± 8℃ in group E.

Conclusion

Wet RF ablation with 5% or 36% NaCl solutions shows better efficiency in creating a large ablation zone than does dry RF ablation or RF ablation with preinjection of NaCl solutions.     

Use of Semiflexible Applicators for Radiofrequency Ablation of Liver Tumors

Purpose To evaluate the feasibility and potential advantages of the radiofrequency ablation of liver tumors using new MRI-compatible semiflexible applicators in a closed-bore high-field MRI scanner. Methods We treated 8 patients with 12 malignant liver tumors of different origin (5 colorectal carcinoma, 2 cholangiocellular carcinoma, 1 breast cancer) under MRI guidance. Radiofrequency ablation (RFA) was performed using 5 cm Rita Starburst Semi-Flex applicators (Rita Medical Systems, Milwaukee, WI, USA) which are suitable for MR- and CT-guided interventions and a 150 W RF generator. All interventions were performed in a closed-bore 1.5 T high-field MRI scanner for MRI-guided RFA using fast T1-weighted gradient echo sequences and T2-weighted ultra-turbo spin echo sequences. Control and follow-up MRI examinations were performed on the next day, at 6 weeks, and every 3 months after RFA. Control MRI were performed as double-contrast MRI examinations (enhancement with iron oxide and gadopentetate dimeglumine). All interventions were performed with the patient under local anesthesia and analgo-sedation. Results The mean diameter of the treated hepatic tumors was 2.4 cm (±0.6 cm, range 1.0–3.2 cm). The mean diameter of induced necrosis was 3.1 cm (±0.4 cm). We achieved complete ablation in all patients. Follow-up examinations over a duration of 7 months (±1.3 months, range 4–9 month) showed a local control rate of 100% in this group of patients. All interventions were performed without major complications; only 2 subcapsular hematomas were documented. Conclusion RFA of liver tumors using semiflexible applicators in closed-bore 1.5 T scanner systems is feasible. These applicators might simplify the RFA of liver tumors under MRI control. The stiff distal part of the applicator facilitates its repositioning.     

CT导向下射频消融治疗肝脏肿瘤

目的 研究射频消融(RFA)对肝脏恶性肿瘤的治疗效果.方法 对30例肝脏恶性肿瘤患者共38个病灶CT引导下进行经皮射频消融治疗,大小2.5～12 cm,其中原发性肝癌26例,转移性肝癌4例.应用美国RIDA 1500型射频消融仪,电极针为15G的9根伞状排列的可伸缩针,电极针打开后最大直径可达5 cm.术前术后均进行增强CT扫描,并定期随访.结果 RFA操作均顺利完成.平均5.5 d后患者康复出院或接受其他方案治疗. 治疗结束后即刻CT平扫,肿瘤内有小点状气体形成者20例,30 d后螺旋CT扫描,增强后38个结节中,直径≤3 cm的4个病灶全部坏死,直径在3～5 cm之间12个病灶,7个全部坏死,5个部分坏死, 直径>5 cm的22个病灶5个全部坏死,均为先行1～2次经肝动脉导管化疗栓塞治疗病人,17个病灶部分坏死.术后常见并发症主要为肝区疼痛、发热、气胸及胸腔积液,无射频治疗相关的死亡.结论 CT引导下经皮射频消融是一种安全有效治疗肝脏恶性肿瘤的方法.     

Radiofrequency Ablation for Treating Liver Metastases from a Non-Colorectal Origin

Objective

We wanted to assess the safety and efficacy of performing radiofrequency ablation (RFA) in patients with non-colorectal liver metastases.

Materials and Methods

In this retrospective study, 25 patients with 40 hepatic metastases (M:F = 17:8; mean age, 57 years; tumor size, 0.5-5.0 cm) from a non-colorectal origin (stomach, biliary, breast, pancreas, kidney and skin) were treated with RFA. The RFA procedures were performed using either an internally cooled electrode or a clustered electrode under ultrasound or CT guidance. Contrast-enhanced CT scans were obtained immediately after RFA and follow-up CT scans were performed within three months after ablation and subsequently at least every six months. The intrahepatic disease-free interval was estimated and the overall survival from the time of the initial RFA was analyzed using the Kaplan-Meier method.

Results

No intraprocedural deaths occurred, but four major complications developed, including abscesses (n = 3) and pneumothorax (n = 1). Technical effectiveness was determined on the initial follow-up images. During the follow-up period (range, 5.9-68.6 months; median time, 18.8 months) for 37 tumors in 22 patients where technical effectiveness was achieved, 12 lesions (32%, 12 of 37) showed local tumor progression and new intrahepatic metastases occurred in 13 patients (59%, 13 of 22). The median intrahepatic disease-free interval was 10.1 months. The 1-year, 3-year and 5-year overall survival rates after RFA were 86%, 39% and 19%, respectively.

Conclusion

RFA showed intermediate therapeutic effectiveness for the treatment of non-colorectal origin liver metastases.     

Stereotactic Radiofrequency Ablation for Liver Tumors in Inherited Metabolic Disorders

Purpose

Both glycogen storage disease type Ia (GSD Ia) and tyrosinemia type I (TYR I) are inherited metabolic disorders that can be complicated by formation of liver adenomas in juvenile/young adult age and/or development of hepatocellular carcinoma. We describe the first application of stereotactic radiofrequency ablation (SRFA) in focal lesions in three patients with inherited metabolic disorders affecting the liver.

Methods

SRFA was applied for removal of single large liver adenomas in a 22-year-old woman and a 20-year-old man with GSD Ia and of a suspicious lesion in a 16-year-old girl with TYR I with α-fetoprotein (AFP) elevation.

Results

SRFA was successful. Large scars were avoided, and in the TYR I patient, elevated AFP values promptly returned to normal.

Conclusion

The SRFA technique is a good alternative to surgical resection of focal liver lesions and could greatly help patients with inherited metabolic disorders with liver involvement, including focal liver lesions and potential malignancy.     

CT引导下肝尾叶肝癌的射频消融治疗

目的：探讨CT引导下肝尾叶肝癌射频消融治疗的疗效及安全性。方法选择肝尾叶肝癌患者21例,共计21个病灶（最大病灶大小约为4.6 cm×4.8 cm）行CT引导下RFA治疗。结果病灶完全坏死率为90.5％（19／21）。所有患者均未出现严重不良反应及并发症,并发症多为术后疼痛、胸膜反应、肝包膜下出血等。结论肝尾叶肝癌行RFA治疗安全有效。     

Laser Navigation for Radiofrequency Ablation

A 45-year-old male with renal cell carcinoma secondary to von-Hippel Lindau (VHL) disease presented for radiofrequency ablation (RFA) of kidney tumors. Due to his prior history of several partial nephrectomies and limited renal reserve, RFA was chosen because of its relatively nephron-sparing nature. A laser guidance device was used to help guide probe placement in an attempt to reduce procedure time and improve targeting accuracy. The device was successful at guiding needle placement, as both tumors were located with a single pass. Follow-up CT scan confirmed accurate needle placement, showing an area of coagulation necrosis covering the previously seen tumor.