The significance of invasion of submucosa in the pathological diagnosis of colonoscopic biopsy of colorectal cancer        WEI Xu-biao*, GAO Xian-hua, WANG Hao ,et al. *Department of Colorectal Surgery, Changhai Hospital, the Second Military Medical University, Shanghai 200433, China
Corresponding author: FU Chuan-gang, E-mail: fugang416@126.com
Abstract    Objective    To investigate the clinicopathologic features that are associated with the un-identification of invasion of submucosa(ISM) in biopsy specimen of colorectal cancer. Methonds    Colorectal cancer patients treated in Changhai Hospital from January 2007 to December 2008 were enrolled in the study. Biopsy specimens of colorectal cancers were re-evaluated by two senior pathologists. Clinicopathologic features were analyzed by univariate and multivariate analyses to identify the risk factors of un-identification of ISM in biopsy specimen. Results    Of the 321 cases of colorectal cancers included into the study, 216 (67.3%) were diagnosed as colorectal cancer (with identification of ISM) by biopsy-based pathological examination. The results of univariate analysis indicate that colorectal cancer with smaller biopsy specimen (P= 0.042), mucinous adenocarcinoma (P= 0.003), higher tumor grade (P= 0.001), lymph node metastasis (P =0.011) and deeper invasion (P=0.092) were less likely to be associated with identification of ISM. Multivariate logistic regression analysis revealed that colorectal cancers with higher tumor grade (OR 2.155, 95% CI 1.081-4.296, P =0.029), and smaller biopsy specimen (OR 1.944, 95% CI 1.149-3.290, P =0.013) were less likely to be associated with identification of ISM.  Conclusion    Clinical suspected malignant lesion without identification of ISM in biopsy specimen is highly predictive of more advanced or aggressive colorectal cancer.