Survival Benefit of Japanese Extended Lymphadenectomy for Clinically Node-Negative and Node-Positive Colorectal Cancers.

Abstract

The impact of extended lymphadenectomy for colorectal cancer is still not sufficiently clear. The aim of the present study was to evaluate the survival benefit of extended lymphadenectomy compared with nonextended lymphadenectomy for clinically node-negative and node-positive colorectal cancers. The present study was a retrospective cohort study that used prospectively collected data and a propensity score matching method. The present study was conducted at a single specialized colorectal surgery department. Of the 1314 patients who underwent radical resection with nonextended or extended lymphadenectomy between 1988 and 2007, we included 711 and 603 patients in the cN0 and cN1/2 series. Propensity score matching was applied, and 141 and 63 pairs were extracted from the cN0 and cN1/2 series. Disease-free survival, cancer-specific survival, and overall survival of the 2 groups were calculated and compared. In the cN0 series, no differences were observed in the long-term outcomes between the nonextended and extended groups. In the cN1/2 series, the disease-free survival, cancer-specific survival and overall survival were significantly higher (log rank, p = 0.04, p = 0.02, and p = 0.01, respectively), and the frequency of local recurrence was significantly lower (p = 0.04) in the extended group. The present study was limited by its nonrandomized retrospective design. Extended lymphadenectomy demonstrated a good inhibitory effect on the local recurrence rate and led to improved disease-free survival, cancer-specific survival, and overall survival of patients in the cN1/2 series. See Video Abstract at http://links.lww.com/DCR/A517.