Does Transverse Colon Cancer Spread to the Extramesocolic Lymph Node Stations?

Background: Transverse colon cancers show behavioral differences in terms of the involvement of extramesocolic lymph nodes since they are closely related to all three embryological planes. These tumors have also been observed in the gastroepiploic-omental (GEOM) region, outside their usual regional areas. We will evaluate this new metastatic route in our own cases. Methods: Thirty-four patients (16 female, 18 male) that presented to our clinic with hepatic flexure, transverse colon, and splenic flexure cancer between October 2011 and May 2017 were included in the study. Type of surgery, histopathology, and factors causing metastasis, morbidity, and mortality were evaluated. Results: Cancer was located in the transverse colon in 20 patients (58.8%), hepatic flexure in 10 (29.4%), and splenic flexure in four (11.7%). Lymph node positivity in the GEOM region was present in four patients: in the infrapyloric region and pancreatic head, close to the hepatic flexure in three patients; and the midline of GEOM, close to the inferior body of the pancreas in one patient. Perineural invasion (p < .05) and N stage (p < .05) were associated with GEOM region metastasis. Tumor localization and age significantly increased pleural effusion. Conclusions: In transverse colon and both flexural tumors, we recommend planning the surgery according to the localization of the tumor and including the GEOM, infrapyloric and infrapancreatic areas. It is possible to discuss whether to perform extended excision for all or only selected patients. The best approach seems to be to evaluate the co-factors to manage these patients.