[OA-27] A study of tumour-infiltrating lymphocyte in distal cholangiocarcinoma

Sirada Sangpaibool, Piyapharom Intarawichian and Chaiwat Aphivatanasiri

Department of Pathology, Facolty of Medicine, Khon Kaen University, Khon Kaen, Thailand

Cholangiocarcinoma (CCA) is one of major cancer in Northeast Thailand. Studies reveal tumours can induce immune response due to their altered protein products recognised as foreign bodies by the immune system. Tumour-infiltrating lymphocytes (TILs) can be assessed to represent the mentioned immune response. Recently, TILs are a potential predictive factor of prognosis in many solid tumours; still, data researched in CCA are limited. This study aimed to assess TILs in distal cholangiocarcinoma according to The International TILs Working Group (ITWG) guideline and to correlate it with clinicopathological characteristics and prognosis. TILs were evaluated on H&E sections from surgically resected specimens. Fifty-two cases of distal cholangiocarcinoma were included retrospectively. Average percentages of TILs in each case were calcolated and established into ordinal levels used to correlate with clinicopathologic variables and survival. Following clinicopathologic factors, gender (p < 0.050), specific growth pattern (p = 0.010) and nuclear pleomorphism (p = 0.010) correlated with TILs levels. Furthermore, TILs levels corresponded significantly to the overall survival (p < 0.010). In conclusion, TILs are significantly associated with prognosis in distal cholangiocarcinoma, similar to other solid tumours.

Keywords: cholangiocarcinoma; pathology; prognosis; tumour-infiltrating lymphocytes