Re188 lipiodol therapy in liver cancer with portal vein thrombosis: a promising alternative

Introduction: Hepatocellular carcinoma (HCC) is the fifth most common malignancy and the third leading cause of cancer related deaths in the world. 10-40% of HCC have portal vein thrombosis (PVT) at presentation; their median survival time is of 2- 4 months. Tyrosine kinase inhibitors have marginal efficacy in improvement of survival in these patients at the cost of poor tolerability. Our aim was to explore Re188 lipiodol trans arterial radionuclide therapy as an alternative treatment in HCC with PVT. Materials and Methods: Patients of HCC with PVT having Eastern Co-operative Oncology Group (ECOG) performance status ≤2 were recruited from Liver Cancer Clinic, AIIMS, New Delhi. Baseline serum alpha-fetoprotein (AFP) and triple phase MRI were obtained. Empirical dose of Re188-lipiodol was estimated as per tumor to liver ratio and Re-188 was labeled with either HDD or N-DEDC complex. Patients underwent a scout scan (with transarterial ~185MBq Re188 labeled lipiodol) to look for hepato-pulmonary shunts. Thereafter, shunt corrected dose was injected selectively into tumor feeding artery. Patients remained under observation for 48-72 hours. Planar and SPECT-CT scans were acquired at 6, 24 and 48hrs. Clinical, radiological and biochemical follow up was done 3 monthly. Radiological response was assessed using mRECIST criteria. Results: Thirteen patients (11 male, 2 female) with mean age of 58.8 (±2.7) years were recruited. Seven out of thirteen were injected Re188-HDD lipiodol (mean dose 2.61±0.15GBq) and six were injected Re188-N-DEDC lipiodol (2.67±0.12GBq). One patient was lost to hepatic encephalopathy at the end of two weeks. Three of the rest twelve (25%) showed complete biochemical, clinical and radiological response. One of them relapsed after 9 months and was re-treated. Three out of twelve showed disease progression; one developed pulmonary metastases, one developed new hepatic lesion and one showed increase in size of treated lesion. The remaining six (50%) had clinical, biochemical and radiological stable disease. Median follow-up period is of 9 months (minimum of 3months); with no disease progression in 9 (69%) and two patients remaining disease free. Conclusions: Re-188 lipiodol trans-arterial radionuclide therapy appears to be a promising alternative treatment in HCC with PVT. However, more work in this area maybe required for streamlining dosimetry and patient selection in order to improve outcome.