Role of yttrium-90 in the management of unresectable hepatocellular carcinoma and hepatic metastases.

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is the sixth most common cancer and third leading cause of cancer-related death in the world. The management of unresectable HCC and hepatic metastases from various solid tumors is a clinical dilemma. There is paucity of data on the treatment of unresectable HCC and hepatic metastases with yttrium-90 (90Y) radioembolization.

METHODS: Thirty patients (mean age; 55.2 years; range 43-82 years) comprising 21 patients with HCC (12 patients have cirrhosis of which 3 patients belong to Child-Pugh class A and 9 patients belong to Child-Pugh class B), 7 patients with metastasis from colorectal cancer, 1 patient with metastasis from melanoma, and 1 patient with metastasis from ovarian carcinoma underwent resin-based 90Y radioembolization between 2013 and 2015 in our study. In all the patients, after embolization of non-target vasculature, SPECT and planar scintigraphy were done with the injection of 5-6 mCi (185-222 MBq) of 99mTc-labeled macroaggregated albumin (MAA) into the hepatic artery. Then, lung shunt fraction was assessed and dose was calculated based on body surface area (BSA) method for SIR-Spheres. Post therapeutic 90Y bremsstrahlung SPECT and 90Y PET was performed within 30 hours following therapy to see the hepatic and extrahepatic  distribution of spheres. Side effects following therapy were noted in all the patients. All patients were followed up with triphasic CT liver 3 months following therapy. Therapeutic response was evaluated with necrosis criteria used for therapy response assessment in solid tumors.

RESULTS: On follow up, 14 patients (46 %) developed minor side effects following treatment and resolved without active intervention. The most common side effects include mild abdominal pain in 11 patients (36 %), nausea in 8 patients (26 %), and fatigue in 6 patients (20 %). On follow up imaging at 3 months following treatment, a complete response was observed in two patients (7 %), partial response in seven patients (23 %), stable disease in 15 patients (50 %), and progressive disease in six patients (20 %).

CONCLUSION: This study provides supportive evidence of the safety and efficacy on 90Y radioembolization for the treatment of unresectable HCC and hepatic metastases from various solid tumors. 90Y PET is a better radionuclide technique for assessing the hepatic and extrahepatic distribution of spheres following therapy compared to 90Y Bremsstrahlung SPECT. Thus, 90Y radioembolization is proving to be promising treatment with average disease control rates around 80 % and should be widely utilized.