Objective: To study the patterns and prognostic value of resection margin involvement and lateral pelvic metastases, providing surgeons with pathologic proofs of tumor spread within the studied areas.
Methods: Large tissue slices of 62 specimens from patients with rectal cancer were used in the pathologic study and the outcomes were followed.
Results: Compared with patients without margin involvement, patients with circumferential margin involvement (CMI), seen in 8 cases (12.9%), had poorer postoperative survival (P=0.003). The 12 patients (19.4%) with lateral pelvic metastases suffered poorer survival, compared with those without lateral pelvic metastases (P=0.026). Eight patients (66.7%) were diagnosed to have single lateral pelvic region involved, while the other 4 had multiple regions involved. The incidence of lateral metastases differed among regions, with higher occurrence in the root of middle rectal artery (6/12, 50.0%), area of the internal iliac artery (4/12, 33.3%) and the obturator region (3/12, 25.0%).
Conclusion: Occurrence of CMI or lateral metastases in rectal cancer patients predispose poor survival, thus a more radical clearance and postoperative adjuvant therapy are recommended.