Neoadjuvant therapy for rectal cancer decreases the number of lymph nodes harvested in operative specimens

BACKGROUND: We evaluated the effect of neoadjuvant therapy (NAT) on lymph node harvest in rectal cancer patients undergoing anatomic resection with curative intent. METHODS: A prospectively maintained database was retrospectively queried for rectal cancer cases from 1990 to 2010. Demographic data, NAT, and lymph node yield were analyzed. Nonanatomic resections were excluded. RESULTS: Five hundred two cases were identified; the mean age was 68 years (range 34-89), and 56% were men. One hundred fifty-one (30%) patients received NAT. Overall, the lymph node yield was diminished in proctectomy specimens after NAT (mean = 9, median = 7) compared with specimens without therapy (mean = 13, median = 10, P = .001). Age was not a significant factor in the lymph node yield (P = .213 and .329). Among patients treated with NAT, younger patients had a significantly lower lymph node yield (P < .0001). CONCLUSIONS: A decreased lymph node yield in proctectomy specimens from patients treated with NAT is consistent with prior studies. Younger patients had a greater reduction in lymph node harvest after NAT compared with senior patients. (C) 2013 Elsevier Inc. All rights reserved.