The prognostic significance of primary tumor volume by MRI in cT3 low rectal cancer / 中国实用外科杂志

ABSTRACT

OBJECTIVE: To evaluate the clinical significance of primary tumor volume(PTV) by preoperative highresolution MRI measurement in subgroup of cT3 low rectal cancer. METHODS: A total of 99 patients with low rectal cancer who confirmed by pathology and assessed at stage-cT3 by MRI,did not undergo neoadjuvant chemoradiotherapy(nCRT) treated in Department of Colorectal Surgery,Fujian Medical University Union Hospital from June 2010 to December 2012 were adopted in the study. The relations between PTV and the depths of tumor infiltration out of mesorectum were analyzed through Spearman correlation analysis. The receiver-operating characteristic(ROC) curve was used to analyze the PTV and 3-year disease-free survival. Cox proportional hazard model was performed for influence factors analysis. RESULTS: The depth of tumor infiltration mesorectum and the PTV were revealed significantly correlated(P 15 cm~3 or PTV≤14.8 cm~3/>14.8 cm~3. The difference between groups revealed significant in the 3-year disease-free survival rate,the local recurrence rate and the distant metastases rate.COX regression analysis was utilized for 3-year disease-free survival,and the multivariate analysis indicated that PTV was an independent impact factor(HR=0.180,95%CI 0.078-0.415,P<0.05). CONCLUSION: The primary tumor volume (PTV) by preoperative high-resolution MRI measurement might be used as a new prognostic parameter for cT3 low rectal cancer.