High tumor budding predicts a poor prognosis in resected duodenal adenocarcinoma

Purpose Tumor budding is a histological characteristic defined as the presence of small clusters of cancer cells at the invasion front. Its significance in duodenal adenocarcinoma (DA) has not been fully described. Methods A single-center, retrospective study was conducted. Patients who underwent curative surgery for histologically diagnosed DA from January 2006 to December 2018 at Kansai Medical University Hospital were included. Tumor budding was counted per 0.785 mm(2) and classified as low (0-4 buds), intermediate (5-9 buds), or high (>= 10 buds). Results In total, 47 patients were included. The 5-year overall survival and relapse-free survival rates were 77% and 72%, respectively. High tumor budding was seen in 15 patients (32%). Excluding patients with superficial type (pT1) DA (n = 22), high tumor budding [hazard ratio (HR) 13.4, p = 0.028], regional lymph node metastasis (HR 19.9, p = 0.039), and adjuvant chemotherapy (HR 0.056, p = 0.036) were independent factors related to the overall survival in multivariate analyses. Distant metastases occurred significantly more often in patients who had high tumor budding than in others (p = 0.039). Conclusion The data suggest that high tumor budding is a predictor of a poor prognosis in resected DA.