ESMO Congress 2023 | OncologyPRO

Abstract 127P

Background

Although tumor budding (TB) has been recognized as a representative adverse prognosticator in gastrointestinal malignancies, it is not well elucidated in distal-extrahepatic bile duct carcinoma (DBDC).

Methods

Herein, we investigated the prognostic significance of peritumoral (PTB) and intratumoral (ITB) budding according to the modified DBDC staging of the 8^th edition of the American Joint Committee on Cancer. PTB and ITB were independently evaluated in a cohort of DBDC patients (n=410) based on the 2016 International Tumor Budding Consensus Conference (ITBCC).

Results

High levels of PTB (PTB^High, ≥ grade 2) and ITB (ITB^High, ≥ grade 3) were identified in 316 (77%) and 238 (58%) cases, respectively. In univariate analysis, PTB^High and ITB^High (both P=0.001); larger size and sclerosing tumor growth pattern (both P<0.001); higher histologic grade (P=0.006); extrapancreatic location (P=0.015); adenocarcinomas unrelated to intraductal papillary neoplasm of the bile duct (IPNB) (P=0.008); pancreatic, duodenal, and lymphovascular invasion (all P<0.001); perineural invasion (P=0.003); cancer involvement of the bile duct resection margin, nodal metastasis, and higher T and N categories and disease stages (all P<0.001) were associated with shorter patient overall survival (OS) times. In multivariate analysis, PTB^High and ITB^High remained poor independent prognostic indicators of OS in DBDC patients. Specifically, ITB^High could predict poor prognosis (P=0.025) in patients with stage I (T1N0) DBDC.

Conclusions

Both PTB^High and ITB^High were strong prognostic indicators in patients with DBDC. Thus, ITB could be used to predict worse prognoses in patients with DBDC, in which PTB is difficult to assess, especially for patients with stage I (T1N0) DBDC.