Clinical Impact of A Macroscopically Complete Resection of Colorectal Cancer with Peritoneal Carcinomatosis

Background. So far, few reports have focused on the clinicopathological features and patterns of recurrence after a complete resection, of peritoneal carcinomatosis (PC) of colorectal origin. The purpose of the present study was to show the clinicopathological features of a macroscopically complete resected tumor and the pattern of recurrence after the curative resection of colorectal PC.Methods. In 153 patients with colorectal PC, 31 patients who underwent a complete resection of a synchronous primaly lesion of a colorectal PC between 1998 and 2007 were assessed retrospectively.Results. Clinicopathological differences were observed in the tumor location, presence of extraperitoneal metastases, extent of PC, and presence of lymph node metastases between a macroscopically complete resection and noncomplete resection patients (P =.045, P <.0001, P <.001, and P =.039, respectively). Tumor recurrence after the complete resection of colorectal PC was observed in 24 patients (77.4%). The 5-year survival rate after complete resection was 36.0%. The survival rate in the macroscopically complete resection group was higher than in the incomplete resection group (P <.001). The 5-year intra- and extraperitoneal recurrence survival rates were 63.9% and 33.8%, respectively. No significant clinicopathological factors affected intraperitoneal recurrence-free survival. Conversely, a univariate analysis using the log-rank test revealed that extended PC and presence of lymph node metastases were MOT factors affecting extraperitoneal recurrence (P = .009 and P = .023, respectively). Eleven of 31 patients survived for 5 years after resection. Two of the 4 patients with liver metastases had received a hepatectomy.Conclusion. Although the 5-year survival rate after a macroscopically complete resection for colorectal PC approached 36.0%, 77.4% of patients developed intra- and extraperitoneal recurrence. Extended PC and presence of