Comparison of tumor response by Response Evaluation Criteria in Solid Tumors (RECIST) and modified RECIST in patients treated with sorafenib for hepatocellular carcinoma

BACKGROUND: A significant improvement in overall survival (OS) was demonstrated in patients with advanced hepatocellular carcinoma (HCC) who received sorafenib (Sor) in the Sorafenib HCC Assessment Randomized Protocol (SHARP) study, in contrast to a response rate (RR) of 2% assessed according to Response Evaluation Criteria in Solid Tumors (RECIST). Modified RECIST (mRECIST) were developed to assess the response in patients with HCC, based on measurement of viable tumor with arterial enhancement on a computed tomography (CT) scan. In the current study, mRECIST were evaluated and were compared with RECIST in patients who received Sor for advanced HCC. METHODS: The authors retrospectively analyzed 53 patients who received Sor for advanced HCC. Patients must to have undergone a 4-phase CT scan before treatment and repeatedly thereafter. CT scans were analyzed using RECIST 1.1 and mRECIST. RESULTS: The rates of objective response (OR), stable disease (SD), and progressive disease (PD) were 2%, 79%, and 19%, respectively, according to RECIST and 23%, 57%, and 21%, respectively, according to mRECIST (P < .001). Patients who achieved an OR according to mRECIST had a longer OS than nonresponding patients with SD or PD (median OS, 18 months and 8 months, respectively; P = .013). In the 42 patients who achieved SD according to RECIST, OS differed depending on tumor response according to mRECIST, with a median OS of 17 months, 10 months, and 4 months for patients who achieved an OR (n = 11), SD (n = 29), and PD (n = 2), respectively (P = .016). CONCLUSIONS: The current series validated mRECIST in patients who received Sor for advanced HCC. The majority of patients who had SD according to RECIST had a different prognosis according to mRECIST. The results indicated that, for patients with HCC, mRECIST should be used for the standard assessment of treatment efficacy, particularly in patients who are receiving antiangiogenic drugs.