Management of liver metastases (oligometastatic) by high-dose-rate interstitial brachytherapy: A case series.

Purpose: To evaluate the feasibility, efficacy, and safety of interstitial brachytherapy in cases of oligo-metastatic liver disease.

Materials and method: Four cases of liver metastases were managed over a period of 1 year in our center with close follow-up. All patients had progressive disease with histopathologially proven liver metastases and were ineligible for surgery. The procedure involved placement of brachytherapy catheters under computed tomography (CT) guidance post placement of a single 6F angiography sheath. The median size of metastasis was 2.9 cm (range 2.2-3.4 cms) in diameter, and a single fraction of radiation dose (10 to 13 Gy) was delivered. The angiography sheath and brachytherapy catheters were removed under fluoroscopic guidance post completion of the procedure with the help of an interventional radiologist. The fluoro guidance for removal of catheters was to observe any bleed. Response to treatment in terms of control of the metastases along with complications, safety, and efficacy of the procedure was observed.

Results: All patients underwent re-evaluation with WB-PET-CT after 1 and 6 months. In three cases, complete response with no metabolic activity was noted on WB-PET-CT scan, and in one case, there was a partial response with a decrease in the size and metabolic activity of the metastasis. No fatal complications were noted; however, acute complications like grade 1 nausea, grade 1 vomiting, pain, and local hemorrhage were noted within 1 week of the procedure.

Conclusion: Liver interstitial brachytherapy is a feasible option in patients with maybe oligo metastatic solid tumors requiring a multi-disciplinary team effort. It is also an option for patients who are unfit for surgical excision. This is the first reported case series in India using high-dose-rate (HDR) brachytherapy techniques with an angiography sheath and flexible brachytherapy catheters.