TROP-2 Expression and Complex Glandular Pattern in Resected Pancreatic Ductal Adenocarcinoma: An Exploratory Clinicopathological Study

This study aimed to evaluate TROP-2 immunoexpression and complex glandular pattern (CGP) in resected pancreatic ductal adenocarcinoma (PDAC) and to investigate their associations with clinicopathological and histopathological features and survival outcomes. This retrospective study included 73 treatment-naïve patients who underwent pancreatic resection for PDAC between 2016 and 2024. TROP-2 expression was assessed immunohistochemically using the H-score, while CGP was evaluated as the percentage of the total invasive tumor area. Associations with clinicopathological and histopathological variables were analyzed using appropriate non-parametric tests. Overall survival (OS) and disease-free survival (DFS) were evaluated using Kaplan–Meier and Cox proportional hazards analyses. The median TROP-2 H-score was 160 (IQR, 110–195), and the median CGP percentage was 20% (IQR, 5–60%). TROP-2 H-score showed a weak positive correlation with CGP percentage (Spearman ρ=0.252, p=0.031) but was not significantly associated with AJCC stage or other adverse clinicopathological features. Higher CGP percentage was associated with increasing tumor budding grade (Holm-adjusted p=0.024) and was higher in tumors with necrosis (p=0.013) and perineural invasion (p=0.018). No significant differences in OS or DFS were observed according to TROP-2 expression or CGP category. Continuous TROP-2 H-score and CGP percentage were also not significantly associated with OS or DFS in multivariable Cox regression analyses. CGP was associated with selected adverse histopathological features in resected PDAC, whereas TROP-2 expression showed only a weak relationship with CGP. These findings support further investigation of CGP as a morphological marker and of TROP-2 as a potential therapeutic target in larger, independently validated PDAC cohorts.