Tumour budding in preoperative biopsy specimens is a useful prognostic index for identifying high-risk patients in early-stage (pN0) colon cancer

Abstract

Background/aim: Tumour budding (BD) is considered a valuable prognostic factor in colon cancer (CC), but its use in daily practice is uncertain. We investigated the prognostic effect of BD using preoperative biopsy specimens in a fairly homogeneous population. Materials and methods: Eighty-two (pN0) CC patients who underwent surgery after preoperative biopsy between 1997 and 2013 were included in the study. Model A (using the ‘deeply invasive blocks & hot-spot area & invasive margin) and method 1 (using the '20× objective & immunohistochemistry staining & quantitive counting’) were used as standard methods. Results: High BD was significantly associated with poor prognostic factors (lymphatic invasion [P = 0.008], perineural invasion [P = 0.041], advanced pT [P = 0.015], invasive margin [P = 0.008], and margin involvement [P = 0.019]). Moreover, correlations between different BD estimates (r = 0.613-0.696), reproducibility of study (Κappa = 0.68-0.73), and usefulness of cut-off value (area of under ROC = 0.746 [0.663-0.829]) were well. In univariate analysis, 5-year survival was poor in patients with high BD (relaps-free survival [RFS]: 71 %, P < 0.001; overall survival [OS]: 73 %, P = 0.004, local recurrence [LR]: 18 %, P = 0.032). Multivariate analyses confirmed that high BD is an independent worse survival parameter for RFS (Hazard ratio [HR]: 1.53 [1.14-2.80], P = 0.015), OS (HR: 1.44 [1.17-2.75], P = 0.032, and LR (HR: 1.59 [1.05-2.76], P = 0.045). Conclusion: Our data show that BD provides valuable prognostic information for early-stage (pN0) CC in preoperative biopsy specimens and that adding BD to current risk classification may contribute to better patient selection.