Histopathologic outcome of neoadjuvant image-guided therapy of hepatocellular carcinoma

The best curative treatment for hepatocellular carcinoma (HCC) is liver transplant (LT), with the limitation to either a solitary lesion < 5 cm or up to three lesions < 3 cm each. Arresting tumor growth or downstaging to make patients eligible for LT can be obtained by neoadjuvant treatments such as transarterial chemoembolization (TACE), selective internal radiation therapy (SIRT), chemical or radiofrequency ablation (RFA). We evaluated the histopathologic response in explant specimens to neoadjuvant image-guided therapy of HCC prior to LT.

Twenty-eight patients with 39 HCC nodules eligible for LT underwent neoadjuvant image-guided therapy 1-393 days prior to transplant. Treatment included TACE (5 nodules), SIRT (7 nodules), RFA (12 nodules), chemical ablation (3 nodules) combined TACE and acetic acid injection (1 nodule) and combined TACE and RFA (11 nodules). 19/28 patients not transplanted within 30 days had interval MRI and 3 patients with progressive disease were retreated.

Residual viable tumor was seen in 42% of patients with post-treatment imaging. Explant pathology revealed viable tumor in 35 of 39 (90%) treated nodules and somewhere in the explanted liver in all patients. Viability and/or progression of the treated tumor was noted in 5/5 nodules treated with TACE, 6/7 with SIRT, 11/12 with RFA, 2/3 with chemical ablation and 11/12 with combined treatment.

Viable local or remote tumor was identified on explanted liver in the majority of patients with HCC after neoadjuvant therapy, despite apparent successful treatment on MRI.