Tumour buds determine prognosis in resected pancreatic ductal adenocarcinoma

BACKGROUND: The prognostic effect of tumour budding was retrospectively analysed in a cohort of 173 patients with resected pancreatic ductal adenocarcinomas (PDACs) of the prospective clinical multicentre CONKO-001 trial. METHODS: Haematoxylin and eosin (H&E)-stained whole tissue slides were evaluated. In two independent approaches, the mean number of tumour buds was analysed according to the consensus criteria in colorectal cancer, in one 0.785 mm(2) field of view and additionally in 10 high-power fields (HPF) (HPF = 0.238 mm(2)). RESULTS: Tumour budding was significantly associated with a higher tumour grade (p < 0.001) but not with distant or lymph node metastasis. Regardless of the quantification approach, an increased number of tumour buds was significantly associated with reduced disease-free survival (DFS) and overall survival (OS) (10 HPF approach DFS: HR = 1.056 (95% CI 1.022-1.092), p = 0.001; OS: HR = 1.052 (95% CI 1.018-1.087), p = 0.002; consensus method DFS: HR = 1.037 (95% CI 1.017-1.058), p < 0.001; OS: HR = 1.040 (95% CI 1.019-1.061), p < 0.001). Recently published cut-offs for tumour budding in colorectal cancer were prognostic in PDAC as well. CONCLUSIONS: Tumour budding is prognostic in the CONKO-001 clinical cohort of patients. Further standardisation and validation in additional clinical cohorts are necessary.