Conversion surgery for hepatocellular carcinoma with portal vein tumor thrombus after successful atezolizumab plus bevacizumab therapy: a case report

Abstract

Background The treatment of hepatocellular carcinoma (HCC) requires diverse and multidisciplinary approaches. In recent years, new agents with good antitumor effects have emerged for systemic chemotherapy, and conversion surgery (CS) after systemic chemotherapy is expected to be an effective treatment strategy for unresectable HCC. We herein report a case of unresectable HCC with portal vein tumor thrombus (PVTT) in which atezolizumab plus bevacizumab therapy induced PVTT regression, followed by CS with R0 resection. Case presentation The patient was a 79-year-old man with S2/S3 HCC who was referred to our department due to tumor re-growth and PVTT after two rounds of transcatheter arterial chemoembolization. The PVTT extended from the left portal vein to the main trunk, and it was determined that the resection of the left portal vein would be difficult to perform with R0 status. Based on the diagnosis of unresectable HCC, treatment with atezolizumab plus bevacizumab was initiated. After two courses of treatment, contrast-enhanced computed tomography showed that the PVTT had regressed to the peripheral side of the left portal vein, and R0 resection became possible. The patient developed grade 3 skin lesions as an immune-related adverse event, and it was determined that the continuation of chemotherapy would be difficult. Four weeks after the second course of atezolizumab plus bevacizumab administration, left lobectomy was performed. Intraoperative ultrasonography was used to confirm the location of the tumor thrombus in the left portal vein during the resection, and a sufficient surgical margin was obtained. The histopathological findings showed that primary tumor and PVTT were mostly necrotic with residues of viable tumor cells observed in some areas. The liver background was determined as A1/F4 (new Inuyama classification). The resection margins were negative, and R0 resection was confirmed. There were no postoperative complications. No recurrence was observed as of five months after surgery. Conclusions CS with atezolizumab plus bevacizumab therapy has potential utility for the treatment of unresectable HCC with PVTT.

Conversion therapy of a giant HCC with portal vein thrombus and inferior vena cava tumor thrombus

“…In fact, several CS cases after Atez+Bev or lenvatinib have been reported. Hidaka et al reported CS after treatment with Atez+Bev for HCC with portal vein tumor thrombus [25] . Hoshino et al reported the case of a HCCv15 cm in diameter occupying the right lobe with adrenal metastasis and invasion of the inferior vena cava, treated with 9 courses of Atez+Bev followed by CS [26] .…”

Conversion to Curative Resection and Pathological Complete Response Following Targeted Therapies With Atezolizumab and Bevacizumab for Initially Unresectable Hepatocellular Carcinoma: A Case Report

“…Atezolizumab plus bevacizumab combination chemotherapy showed good anti-tumor activity in patients with previously unresectable HCC, with a median progression-free survival of 5.6 months, an overall response rate of 27.3%, and a complete response of 5.5% in a Phase 1b study [2,12]. In addition, certain cases of conversion surgery for unresectable hepatocellular carcinoma following atezolizumab and bevacizumab therapy have been reported [3,4].…”

“…The combination of the PD-L1 monoclonal antibody atezolizumab and the anti-VEGF monoclonal antibody bevacizumab became the first-line treatment for unresectable HCC [2]. Furthermore, after receiving atezolizumab plus bevacizumab therapy, there have been some instances of conversion surgery for unresectable HCC [3,4].…”

Surgery for Hepatocellular Carcinoma With Macroscopic Vascular Invasion in the Era of Modern Molecular Therapy

“…Conversion hepatectomy is one of the essential options for prolonging survival in patients with initially unresectable HCC that has been down-staged to being resectable by conversion therapy (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44). The number of articles on the advantages of conversion surgery after molecular therapy has increased.…”

“…After the initiation of molecular therapy, the number of patients with complete response (CR) by response evaluation criteria in solid tumors (RECIST) and modified RECIST (mRECIST) criteria in diagnostic imaging increased; in contrast, complete remission of HCC is rarely achieved by molecular therapy alone (36). Conversely, many long-term survivors, including those completely cured, have been reported in patients with initially unresectable HCC after molecular therapy followed by conversion surgery (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43). Partial response (PR) or stable disease after molecular therapy is required for patients to undergo conversion surgery, but CR is not always required (31).…”