Down-staging of hepatocellular carcinoma via external-beam radiotherapy with subsequent liver transplantation: a case report.

Despite the widespread use of locoregional therapies [radiofrequency ablation and transarterial chemoembolization (TACE)], there is currently a lack of high-quality evidence supporting their use for hepatocellular carcinoma (HCC) in patients on the liver transplantation (LT) waiting list or requiring down-staging. Radiotherapy has rarely been used in this setting and has usually been in the form of more complex and less accessible techniques such as proton-beam and stereotactic body radiation therapy. Only 1 report describes the use of conventional 3-dimensional conformal external-beam radiotherapy (cEBRT) techniques as neoadjuvant or down-staging therapy for patients who are LT candidates. This report describes the use of cEBRT in a 52-year-old hepatitis C-positive man with cirrhosis. A 40-mm right lobe HCC was treated initially with TACE while he was on the waiting list. The lesion progressed beyond transplant criteria (76 mm). Conventional external-beam radiotherapy (EBRT) was used (54 Gy in 27 fractions) to down-stage the lesion. EBRT was well tolerated and resulted in a complete radiological response with no arterial enhancement of the lesion for a total of 16 months. Subsequent LT and a review of the explant demonstrated complete histological necrosis of the lesion. This report provides the first description of complete histological necrosis of HCC through the use of cEBRT techniques as down-staging/neoadjuvant therapy before LT. Because of its potential efficacy, accessibility, tolerability, noninvasive and outpatient nature, and ability to treat lesions adjacent to vessels and biliary structures, further trials examining the efficacy of cEBRT versus other neoadjuvant techniques are urgently required.