Preclinical Benefit of Hypoxia-Activated Intra-arterial Therapy with Evofosfamide in Liver Cancer.

PURPOSE: To evaluate safety and characterize anticancer efficacy of hepatic hypoxia-activated intra-arterial therapy (HAIAT) with evofosfamide in a rabbit model. EXPERIMENTAL DESIGN: VX2-tumor-bearing rabbits were assigned to 4 intra-arterial therapy (IAT) groups (n = 7/group): (i) saline (control); (ii) evofosfamide (Evo); (iii) doxorubicin-lipiodol emulsion followed by embolization with 100-300 µm beads (conventional, cTACE); or (iv) cTACE and evofosfamide (cTACE + Evo). Blood samples were collected pre-IAT and 1, 2, 7, and 14 days post-IAT. A semiquantitative scoring system assessed hepatocellular damage. Tumor volumes were segmented on multidetector CT (baseline, 7/14 days post-IAT). Pathologic tumor necrosis was quantified using manual segmentation on whole-slide images. Hypoxic fraction (HF) and compartment (HC) were determined by pimonidazole staining. Tumor DNA damage, apoptosis, cell proliferation, endogenous hypoxia, and metabolism were quantified (γ-H2AX, Annexin V, caspase-3, Ki-67, HIF1α, VEGF, GAPDH, MCT4, and LDH). RESULTS: cTACE + Evo showed a similar profile of liver enzymes elevation and pathologic scores compared with cTACE. Neither hematologic nor renal toxicity were observed. Animals treated with cTACE + Evo demonstrated smaller tumor volumes, lower tumor growth rates, and higher necrotic fractions compared with cTACE. cTACE + Evo resulted in a marked reduction in the HF and HC. Correlation was observed between decreases in HF or HC and tumor necrosis. cTACE + Evo promoted antitumor effects as evidenced by increased expression of γ-H2AX, apoptotic biomarkers, and decreased cell proliferation. Increased HIF1α/VEGF expression and tumor glycolysis supported HAIAT. CONCLUSIONS: HAIAT achieved a promising step towards the locoregional targeting of tumor hypoxia. The favorable toxicity profile and enhanced anticancer effects of evofosfamide in combination with cTACE pave the way towards clinical trials in patients with liver cancer. Clin Cancer Res; 23(2); 536-48. ©2016 AACR.

Lack of response after initial chemoembolization for hepatocellular carcinoma: does it predict failure of subsequent treatment?

PURPOSE: To (a) evaluate the response of hepatocellular carcinoma (HCC) to chemoembolization after initial nonresponse, as determined with European Association for the Study of the Liver (EASL) criteria and modified Response Evaluation Criteria in Solid Tumors (mRECIST), and (b) compare posttreatment survival of initial nonresponders versus that of initial responders. MATERIALS AND METHODS: The institutional review board approved this retrospective study, which was compliant with HIPAA. A total of 116 consecutive patients (96 men, 20 women; mean age, 63 years) with unresectable HCC who underwent at least two chemoembolization procedures were included. The chemoembolization mixture consisted of 100 mg of cisplatin, 50 mg of doxorubicin, and 10 mg of mitomycin C mixed 1:1 with iodized oil. Tumor response at magnetic resonance imaging was evaluated after each chemoembolization procedure according to EASL criteria and mRECIST. The survival rate in each subgroup was calculated and correlated with response. The Wilcoxon test was used to test group comparability. Kaplan-Meier estimators were used to generate survival curves and compared by using the log-rank test. RESULTS: No response to initial chemoembolization was seen in 43% and 50% of patients according to EASL criteria and mRECIST, respectively. After a second chemoembolization procedure, 44% (EASL) and 47% (mRECIST) of initial nonresponders showed a significant response. With EASL criteria, the 1-, 2-, and 3-year survival rates (±standard error of the mean) after two chemoembolization procedures were 39%±10, 14%±7, and 0%, respectively, for nonresponders and 68%±10, 50%±11, and 37%±11 for responders (P=.036, P=.006, and P<.005 at 1, 2, and 3 years). With mRECIST, the 1-, 2-, and 3-year survival rates after two chemoembolization procedures were 49%±9, 20%±8, and 7%±6 for nonresponders and 67%±9, 44%±10, and 36%±9 for responders (P=.174, P=.046, and P=.011 at 1, 2, and 3 years). CONCLUSION: Patients who underwent chemoembolization for HCC showed a response (with both EASL criteria and mRECIST) and improved survival after the second chemoembolization treatment. At least two chemoembolization procedures should be performed in the same targeted lesions before further treatment is abandoned.

Chemoembolization decreases drop-off risk of hepatocellular carcinoma patients on the liver transplant list.

INTRODUCTION: The drop-off risk for patients awaiting liver transplantation for hepatocellular carcinoma (HCC) is 22%. Transplant liver availability is expected to worsen, resulting in longer waiting times and increased drop-off rates. Our aim was to determine whether chemoembolization can decrease this risk. PATIENTS AND METHODS: Eighty-seven consecutive HCC patients listed for liver transplant (Milan criteria) underwent statistical comparability adjustments using the propensity score (Wilcoxon, Fisher's, and chi-square tests). Forty-three nonchemoembolization patients and 22 chemoembolization patients were comparable for Child-Pugh and Model for End-Stage Liver Disease scores, tumor size and number, alpha fetoprotein (AFP) levels, and cause of cirrhosis. We calculated the risk of dropping off the transplant list by assigning a transplant time to those who dropped off (equal probability with patients who were on the list longer than the patient in question). The significance level was obtained by calculating the simulation distribution of the difference compared with the permutations of chemoembolization versus nonchemoembolization assignment of the patients. Kaplan-Meier estimators (log-rank test) were used to determine survival rates. RESULTS: Median follow-up was 187 ± 110 weeks (range 38 to 435, date of diagnosis). The chemoembolization group had an 80% drop-off risk decrease (15% nonchemoembolization versus 3% chemoembolization, p = 0.04). Although survival was better for the chemoembolization group, it did not reach statistical significance. Two-year survival for the nonchemoembolization and chemoembolization group was 57.3% ± 7.1% and 76.0% ± 7.9%, respectively (p = 0.078). CONCLUSIONS: Chemoembolization appears to result in a significant decrease in the risk of dropping off liver transplant list for patients with HCC and results in a tendency toward longer survival.