R1 resection for aggressive or advanced colorectal liver metastases is justified in combination with effective prehepatectomy chemotherapy

AimsHere we reassess anticipated inability to obtain a microscopically clear surgical margin as an absolute contraindication to surgery for colorectal liver metastases in view of improvements in treatment modalities adjunctive to surgery.MethodsWe retrospectively analysed 310 patients treated at our institution to estimate the survival benefit from R1 hepatectomy performed to remove liver metastases from colorectal cancer.ResultsConsidering all 310 patients evaluated, the R1 resection group (positive margin; n = 55) showed a lower disease-free rate (P < 0.01) and worse overall survival (P < 0.01) than the R0 resection group (negative margin; n = 255). When patients were divided according to initial resectability, similar differences in disease-free rate and overall survival (P = 0.03) between R1 (n = 19) and R0 (n = 182) were observed in patients whose metastases were resectable. However, superior impact of R0 resection (n = 73) compared to R1 resection (n = 36) on disease-free rate (P = 0.44) and overall survival (P = 0.50) was not confirmed in patients with initially unresectable or marginally resectable metastases, especially those with a favourable response to prehepatectomy chemotherapy.ConclusionsA predicted positive surgical margin after resection no longer should be an absolute contraindication to surgery for aggressive or advanced liver metastases.