A refined prediction of early recurrence combining tumor deposits in patients with resected rectal mucinous adenocarcinoma

Abstract

Purpose: Early recurrence (ER) of rectal mucinous adenocarcinoma (MAC) has yet to be defined. We therefore explored risk factors for ER and constructed a predictive nomogram.

Method: A total of 145 rectal MAC patients undergoing radical surgery were included. The minimum P value method was used to determine the optimal cut-off point to discriminate between ER and late recurrence (LR). Risk factors for ER were determined by a logistic regression analysis, and a predictive nomogram was constructed.

Results: A total of 62 (42.8%) patients developed tumor recurrence. The optimal time to define ER was 12 months. A pre-treatment tumor distance from the anal verge ≤ 7 cm, pathological N stage, lymphovascular invasion, tumor deposits, and time to recurrence ≤ 12 months were significantly associated with a poor post-recurrence survival in patients with recurrence. A pre-treatment serum carcinoembryonic antigen (CEA) level > 10 ng/ml, pre-treatment tumor distance from the anal verge ≤ 7 cm, pathological N + stage, perineural invasion, and tumor deposits were identified as independent risk factors associated with ER. A nomogram predicting ER was constructed (C-index 0.870).

Conclusion: The pre-treatment serum CEA level, pre-treatment tumor distance from the anal verge, pathological N + stage, perineural invasion, and tumor deposits were significantly predictive of ER for rectal MAC patients.

Keywords: Early recurrence; Mucinous adenocarcinoma; Nomogram; Rectal cancer.