Abstract
BACKGROUND: Neoadjuvant chemotherapy (NAC) has been conducted for patients with non-resectable colorectal cancer; however, few reports of a systematic approach to NAC exist. At our hospital, bevacizumab with capecitabine and oxaliplatin (B-mab XELOX) has been used as chemotherapy for Stage IV colorectal cancer since 2014. We aimed to evaluate the efficacy and safety of NAC with a molecular-targeting agent for Stage IV colorectal cancer. METHODS: A retrospective, single-institute analysis was performed including 27 patients with advanced recurrent cancer following primary tumor resection and 43 patients with non-resectable tumors and remote metastasis. At the time of resection, 17 were receiving chemotherapy. All 70 patients received at least 3 cycles of B-mab XELOX (total: 920 cycles). We determined the 1-year progression-free survival (1Y-PFS), 1-year overall survival (1Y-OS), 3Y-PFS, 3Y-OS, and number of treatment cycles. The objective response rate, clinical benefit rate, and adverse events were assessed. The number of chemotherapy cycles, survival time, and R0 surgery rate were determined for patients who underwent RO conversion surgery. RESULTS: The 1Y-PFS was 28.5% [median survival time (MST): 7.4 months], 1Y-OS was 76.6% (MST not reached), 3Y-PFS was 5.5% (MST: 7.4 months), and 3Y-OS was 26.4% (MST: 25.2 months). The mean and median number of cycles of B-mab XELOX was 13.1 and 10.5, respectively. The objective response rate was 28.6%, and the clinical benefit rate was 58.6%. Grade 1 or Grade 2 adverse events occurred in 60 patients (85.7%); however, they all resolved without intervention. A single Grade 4 event (perforation of the primary tumor) occurred in 1 patient (1.4%). RO conversion surgery was performed in 7 patients (10.0%; primary + liver in 2 patients, primary + lung in 1 patient, liver in 3 patients, and primary in 1 patient). These patients received 3 to 10 cycles preoperatively (mean: 7.3; median: 6.5). R0 surgery was achieved in 5 of the 7 patients (71.4%). Postoperative survival ranged from 1 to 26 months (MST: 8 months). CONCLUSIONS: This modified regimen was safe and effective in Japanese patients, and a high quality of life/quality-adjusted life-year was achieved. To further evaluate PFS and OS, more patients are being investigated.