The prognostic value of tumor ?budding? in patients with locally advanced rectal cancer after neoadjuvant chemoradiotherapy

Purpose: The prognostic value of tumor budding and the correlation between tumor budding and other well-known pathological prognostic factors were aimed to be investigated by examining resected rectal specimens of patients treated with or without neoadjuvant chemoradiotherapy.Patients and Methods: The clinicopathologic data and oncologic outcomes of 117 patients with cT3N0 or any cT with positive N locally advanced rectal cancer who received neoadjuvant chemoradiotherapy and 113 patients with cT2N0 or cT3N0 rectal cancer who did not receive neoadjuvant chemoradiotherapy were evaluated between January 2000 and June 2010 prospectively. All patients were clinically staged according to internationally accepted diagnostic standarts and the requirement of neoadjuvant chemoradiotherapy was considered by multidisciplinary colorectal council. According to the definition of Hase et al.(1993), ?Tumor budding? was defined as an isolated single cancer cell or a cluster of cells composed of less than 5 cells of ?budding focus?. The term of ?budding intensity? was used for the number of focuses and was considered as tumor budding grade. Scores were divided into groups according to tumor budding density as none, mild(1-5), moderate(6-10), and severe(>10).Conclusion: Significant association between tumor budding and neoadjuvant chemoradiotherapy, depth of tumor invasion, lymph node metastasis, lymph vessel invasion, venous invasion, local recurrence, distant metastases, and number of metastatic lymph node, were determined. Increasing tumor budding intensity was related with shortened overall and disease-free survival rates.It was demonstrated that tumor budding is an independent prognostic factor for neoadjuvant chemoradiotherapy negative patients, whileas has no prognostic role for neoadjuvant chemoradiotherapy positive patients. There was a significant association between neoadjuvant chemoradiotherapy positive patients and survival rates, but there was no incremental effect of neoadjuvant chemoradiotherapy on disease-free survival rates. It was shown that the presence of lymphatic vessel involvement and venous invasion is significantly related with decreased overall and disease-free survival rates. Positive circumferential resection margin was intensely related with lesser survival rates and close circumferential resection margins were related with decreasing overall and disease-free survival rates in both of the neoadjuvant chemoradiotherapy positive and negative groups.