Clinicopathological characteristics and treatment of multiple primary colorectal carcinoma

Objective To investigate clinicopathological characteristics, diagnosis and treatment of multiple primary colorectal carcinoma (MPCC). Methods From January 2008 to March 2017, 42 patients diagnosed with MPCC underwent surgery at Beijing Shijitan Hospital, Capital Medical University. Their clinicopathological features, diagnosis and treatment were analyzed. Results These 42 MPCC patients accounted for 7.1% (42/592) colorectal cancer patients in the same period. There were 64 intestinal cancer lesions in 32 patients (76.2%) with synchronous carcinoma (SC), and 20 intestinal cancer lesions in 10 patients (23.8%) with metachronous carcinoma(MC), where the interval between the first and the recurrent was 18-105 months. The proportion of patients in the SC group with highly to moderately differentiated adenocarcinoma was significantly higher compared with that of the MC group (P 0.05). Among 42 patients undergoing radical operation, 6 received colonic metallic stent implantation as a bridge to elective resection in 10 patients with colonic obstruction. Conclusion MPCC, mainly two-lesion cancer, is most commonly found in sigmoid colon and rectum. Those with poorly differentiated cancer, mucinous carcinoma and those complicated with adenoma should be closely followed up with colonoscopy. Colonic metallic stent implantation as a bridge to elective resection may improve the detection rate of SC. Key words: Colorectal neoplasms; Neoplasms, multiple primary; DNA mismatch repair; Synchronous carcinoma; Metachronous carcinoma