**4.12. RFA of gastrointestinal stromal tumors**

Pawlik et al at MD Anderson Cancer Center reported a series with 36 non-GIST sarcoma patients and 31 GIST patients who received RFA and/or surgical resection of liver metastases. (47). When surgical resection was possible, that was the first choice (35 patients). RFA was used in combination with surgical resection of the largest lesions in 18 cases. RFA was used alone in 13 cases. Those patients treated with RFA alone, or in combination with

surgical resection, had a significantly higher rate of recurrence (90.9%) than did patients who underwent resection alone (57.1%). However, this difference probably reflects a selection bias, since RFA was never used for patients whose tumors were resectable. Patients who were treated with RFA either alone or as a combined modality with resection also had a shorter disease-free interval (7.4 months) than patients who underwent resection alone (18.6 months). Avritscher et al reported three advanced GIST patients whose focal liver progression was successfully treated with RFA. The patients remained progression-free at 8, 15, and 16 months after ablation (48) .

Hyperthermia and Radiology 161

The authors concluded that endobiliary RFA treatment appears to be safe. They stated that

Today, the technique is a standard treatment for patients with advanced cervical cancer, or patients with less advanced cervical cancer that cannot clinically tolerate chemotherapy. It is recommended and used as an alternative to the international gold standard of combined radiation therapy and cisplatin-based chemotherapy (51). The Dutch Deep Hyperthermia Trial, conducted between 1990 and 1996 and published in the Lancet in 2000, was a prospective, randomized trial that compared the outcomes of 358 patients with advanced bladder, cervical, and rectal tumors. Half of the patients received only radiation therapy and the other half received both radiation therapy and hyperthermia. Three-year outcomes revealed that hyperthermia improved both pelvic control and overall survival rates, but seemed to be most effective for patients with advanced cervical cancer (52). At 36 months, of an original cohort of 114 patients with advanced cervical cancer, the 58 patients receiving both treatments showed a complete response rate of 83%, compared with 57% for the 56 patients who only received radiation therapy. The survival rate was 51% for the combined treatment group, compared with 27% for the radiation therapy-only group. Furthermore, hyperthermia

randomized studies with prolonged follow-up are needed (50).

**4.14. Role of hyperthermia in treatment of cervical cancer patients** 

treatments did not enhance radiation toxicity and were reported to be cost-effective

number of grades 3-5 radiation-induced toxicities (53).

**4.15. Radiofrequency ablation therapy for varicose veins** 

However, long-term outcomes (**12-year follow-up)** was addressed by a follow-up study published in 2008 that tracked outcomes for both groups 12 years following treatment. The patients who received the combined treatment continued to have significantly better outcomes. The outcomes for the combined therapy group remained consistent. At the end of the study period, 37% of this group was still alive, compared with 20% who received radiation only. Of the combined therapy group, 56% retained pelvic tumor control, compared with 37% for the radiation therapy group. Pelvic recurrence developed in 25% of the combined therapy group and 31% of the radiation therapy group. Approximately onethird of both cohorts developed distant metastasis. Both groups experienced the same

Venous insufficiency resulting from superficial reflux because of varicose veins is a serious problem that usually progresses inexorably if left untreated. When the refluxing circuit involves failure of the primary valves at the saphenofemoral junction, treatment options for the patient are limited, and early recurrences are the rule rather than the exception. In the historical surgical approach, ligation and division of the saphenous trunk and all proximal tributaries are followed either by stripping of the vein or by avulsion phlebectomy. Proximal ligation requires a substantial incision at the groin crease. Stripping of the vein requires additional incisions at the knee or below and is associated with a high incidence of minor surgical complications. Avulsion phlebectomy requires multiple 2- to 3-mm incisions along the course of the vein and can cause damage to adjacent nerves and lymphatic vessels. Endovenous ablation has replaced stripping

In an ASCO poster presentation, Dileo et al reported treating 9 patients with percutaneous CT-guided RFA for single or limited site(s) of progressing disease (8 liver lesions and 1 soft tissue lesion). Thee were no complications from the RFA procedure. With median follow-up of 4.2 months (range 1-11 months), all patients had their lesions completely ablated. Five patients developed systemic progression, while 4 patients remain stable on continued treatment with imatinib (median follow-up 5.8 m). The authors concluded "In this small cohort, percutaneous RFA appears to be a safe and effective treatment for localized sites of progression. This procedure helps to manage limited IM-resistant GIST. Continuation of imatinib to control systemic sites of imatinib-sensitive GIST despite emergence of limited clonal resistance can be justified on the basis of this exploratory work." (49)

Evaluating the evidence about RFA for GIST. RFA appears to be a viable palliative option for patients with advanced GIST who develop focal progression of liver or peritoneal disease during imatinib therapy and who are not otherwise candidates for surgical resection. Alternatively, RFA offers a potentially curative option for patients who exhibit a partial response to imatinib and have focal residual disease that is not amenable to surgical resection .The guidelines (NCCN, 2010) also recommend the use of RFA for the treatment of gastrointestinal stromal tumors with limited progression. Progression is defined as a new lesion or increase in tumor size. The NCCN guidelines state that, for limited progressive disease that is potentially easily resectable, surgical resection should be considered. Other treatment options include RFA or embolization.
