West Asia Organization for Cancer Prevention (WAOCP), APOCP's West Asia Chapter. Asian Pacific Journal of Cancer Prevention 1513-7368 24 5 2023 05 01 Synchronous Advanced Colorectal Neoplasia: Clinicopathologic Features and Prognostic Significance 1643 1649 90623 10.31557/APJCP.2023.24.5.1643 EN Sahaphol Anannamcharoen Department of Surgery Phramongkutklao Hospital, Thailand. 000000030274564X Piyapan Cheeranont Department of Surgery Phramongkutklao Hospital, Thailand. 0000000261332602 Thirayost Nimmanon Department of Pathology, Phrmongkutklao College of Medicine, Thailand. 0000000187651268 Chinakrit Boonya-ussadorn Department of Surgery Phramongkutklao Hospital, Thailand. 0000000247595916 Journal Article 2022 12 03 Objective: This study aimed to compare the clinico-pathologic features, recurrence rate and disease-free survival between colorectal cancers (CRCs) with synchronous advanced colorectal neoplasia (SCN) and solitary CRCs to determine the prognostic significance of SCN. Methods: A retrospective review of prospectively collected data of patients with CRCs was conducted in Phramongkutklao Hospital from January 2009 to December 2014. Patients were categorized in 3 groups: 1) solitary CRCs, 2) CRCs with advanced colorectal adenomas (ACAs) but having no another cancer and 3) synchronous colorectal cancers (S-CRCs) with or without ACAs. Patients undergoing curative resection and complete standard adjuvant treatment were recruited to evaluate the prognostic significance of SCN.  Clinicopathologic features, recurrence rate and disease-free survival were analyzed to compare among different groups.  Result: Among 328 recruited patients, 282 were classified as solitary CRCs (86%), 23 as CRCs with ACAs (7%) and 23 as S-CRCs (7%). Patients with CRCs with SCN (groups 2 and 3) were significantly older than patients with solitary CRCs (p <0.01), and SCN was found more commonly among males (15.2%) than females (12.3%) (p=0.045). In all, 288 patients achieved a curative resection and accomplished complete standard postoperative adjuvant treatment. Of these, the accumulative number of patients experiencing tumor recurrence was 11.8, 21.2, 24.6, 26.4 and 26.7% at the 1-, 3-, 5-, 7- and 10-year surveillance period, respectively. The disease-free survival of the groups with SCN was marginally higher than that of solitary CRCs groups (p=0.72) (solitary CRCs, 120.7±4.4 months; CRCs/ACAs, 127.4±13.9 months and S-CRCs: 126.2±13.6 months). Conclusion: CRCs with SCN were found at a more advanced age than those with solitary CRCs. SCN was found more often among males than females. After achieving curative resection and complete adjuvant treatment, the recurrence rate and disease-free survival of CRCs with SCN did not significantly differ from those of solitary CRCs.  https://journal.waocp.org/article_90623_b2a0824ac5472a2223c5dd057a46e237.pdf