Title: Mo1951 Interleukin-29 (Interferon-Lambda 1) Inhibits Growth of Hepatocellular Carcinomas in an Orthotope Murine Tumor Model In Vivo
Abstract: Ten to 20 percent of patients with colorectal cancer with unresectable liver metastases meet the criteria for resection after chemotherapy, leading to improved prognosis. In this “Conversion therapy”, however, it remains unclear which patients will have long-term survival. Therefore, we examined the outcomes of such patients to identify characteristics of long-term survivors after “Conversion therapy”. Methods: Multidisciplinary treatment conferences conducted by radiology, digestive surgery and clinical oncology have evaluated patients for possible conversion therapy since 2006. Preoperative chemotherapy included: mFOLFOX6, FOLFIRI or Xelox (+Bevacizumab). Patients were evaluated for resectability every twomonths. Adjuvant chemotherapy with six months ofmFOLFOX6was administered. Results: Thirty-three patients were enrolled in this study, including 4 patients with a complete remission (CR) (12%) and 17 with a partial response (PR) (52%). Eleven patients underwent hepatic resection (33%; 11/33), including 1 with relapse after CR. Of these 11 patients (7 male, 4 female), age 48-74 years (median 57), 8 had simultaneous lesions, and 3 had metachronous lesions, 4-13 courses of chemotherapy were given before surgery (7). Ten patients underwent an R0 operation. In one patient, tumor nodules were not identified by intra-operative ultrasound, followed by hepatic re-resection after several months. Four of 11 patients are alive without recurrence. Overall survival is 18-55 months (42.5), with 13-40 months after hepatectomy (36), and re-hepatectomy in one case. Lesions disappeared on imaging after chemotherapy in all 4 cases. Pathological CR lesions in the resected specimens were present in 3 cases. Four patients are alive with recurrence. Survival is 4357 months (45.5), along with 6-27 months after relapse (16). Relapse-free survival was more than 12 months after hepatectomy in all 4 cases. Three patients died, with survival of 15-24 months (23), along with 3-8 months after relapse (6). In total, 7 of 11 patients (64%) survivedmore than 40months. All the patients originally had tubular adenocarcinoma. Conclusions: Hepatic lesions with a CR (clinically or pathologically) after chemotherapy, along with the pathology of well to moderately differentiated adenocarcinoma, may be favorable factors to predict long-term survival. Long-term relapse-free patients after first hepatectomy (> 12 months) showed long-term survival (> 40 months) even with recurrent cancer. Early recurrence after hepatic resection was associated with a poor prognosis, similar to patients receiving chemotherapy alone.