Influence of obesity on lymph node recovery from rectal resection specimens

Careful lymph node dissection from colorectal resection specimens is important procedure for cancer staging. Present study intended to assess the impact of surgical technique and patient's obesity on this process. Number of lymph nodes harvested by manual dissection from resection specimens of 141 patients with rectal cancer and the rate of nodal metastases were analyzed and compared in different groups of patients selected by length of resection specimen and body mass index. The median and mean number of lymph nodes found per patient were 6 and 6.7. The shorter resection specimens (<16 cm after formalin fixation) yielded significantly lower number of nodes than those with length > 16 cm (5.7 versus 7.9). Most significant reduction in mean number of lymph nodes was observed in obese patients with short specimens (4.8). This subset of patients presented the lowest rate of nodal metastases (38%). The surgical technique seems to be an important factor for lymph node recovery from rectal resections specimens. The patient's obesity had an unfavourable impact on this procedure. Standardized surgery and histopathological examination are needed even in non-specialized centers to harvest adequate number of lymph nodes.