Cancer histology in metastatic lymph node predicts prognosis in patients with node-positive stage IV colorectal cancer.

Background: Appropriate prognostic indicators are required for patients with stage IV colorectal cancer (CRC). Lymph node metastasis mainly involves four histological types of CRC. Some metastatic lymph nodes (mLNs) showing cribriform carcinoma are associated with distant metastasis in patients with node-positive CRC and are correlated with recurrence and survival in stage III disease. However, the significance of mLN histology in the prognosis of patients with node-positive stage IV disease remains unclear. Methods: We enrolled 449 consecutive patients with CRC who underwent primary tumor resection with lymph node dissection between January 2011 and November 2018. This study included 88 patients with node-positive stage IV CRC and synchronous or metachronous distant metastases. We retrospectively investigated the association between cancer histology in the mLNs based on our classification and cancer-specific survival (CSS) in patients with node-positive stage IV CRC. Results: Kaplan-Meier analysis showed that CSS was better in patients with CRC and all the mLNs showing tubular-type carcinoma. In contrast, patients with at least some mLNs showing poorly differentiated-type carcinoma had poor prognosis. Multivariate analysis showed that "all mLNs showing tubular-type carcinoma" was an independent good prognostic factor for CSS in patients with node-positive stage IV CRC. In addition, "at least some mLNs showing poorly differentiated-type carcinoma" was an independent poor prognostic factor for CSS in patients with node-positive stage IV disease. Conclusions: The histological type of the mLN may indicate a better or poor prognosis for patients with stage IV CRC.

Right posterior bile duct stricture after laparoscopic anterior sectionectomy with long right bile duct: A case report.

Right anterior liver sectionectomy (RAS) is a complicated procedure with high incidences of postoperative complications. We report a case of right posterior bile duct (RPBD) stricture after laparoscopic RAS with discussion of the anatomical aspects. A 69-year-old Japanese man had solitary colorectal liver metastasis. A tumor was located near the root of the right anterior Glissonean pedicle. On postoperative day 6, he had cholangitis and imaging studies showed RPBD stricture. Symptoms disappeared following a course of antibiotics and the patient was discharged on postoperative day 21. The RBPD anatomy type of this patient was a supra-portal pattern with a long (18 mm) right biliary duct, which would be close to the right anterior Glissonean bifurcation. A stapling device might have caused its deformation and resulted in its stricture. As the RPBD has variant anatomy, we had to notice that there may be hazardous types for postoperative RPBD stricture.