Impact on inadequate lymph node harvest on survival in T4N0 colorectal cancer: A would-be medical center experience in Taiwan

Insufficient lymph node harvest (< 12) may lead to incorrect classification of stage I and II disease. Many studies have indicated a poor prognosis with inadequate lymph node harvest in stages I to III, but few studies have demonstrated the relationship between low lymph node harvest and T4 disease. This study aimed to identify the influence of insufficient number of lymph nodes harvested on survival in T4N0 colorectal cancer. We enrolled patients with T4N0 colorectal cancer who underwent radical resection between 2010 and 2016. A total of 155 patients were divided into 2 groups; 142 patients had ≥ 12 harvested lymph nodes, and the other 13 had < 12 lymph nodes. All patients were followed up for at least 5 years. The primary outcome was the impact of the number of lymph nodes harvested on disease-free survival and overall survival, which were investigated using Kaplan-Meier survival techniques. There were no significant differences in recurrence rate, emergent or elective surgery, laparoscopic or open surgery, or chemotherapy between the 2 groups. Kaplan-Meier analyses showed no statistical differences in 5-year disease-free survival (P = .886) and 5-year overall survival (P = .832) between the groups. There were no significant differences in disease-free survival and overall survival between patients with adequate (≥ 12) and inadequate (< 12) lymph node harvest in T4N0 colorectal cancers.