Sex-based differences in gallbladder cancer associated with pancreaticobiliary maljunction

Background/Aims: Gallbladder cancer predominantly affects women; this sex-based difference is influenced by factors such as gallstones, sex hormone and genetic susceptibility. Gallbladder cancer is also frequently associated with pancreaticobiliary maljunction (PBM) without biliary dilatation. We examined sex-based differences in gallbladder cancer associated with PBM. Methodology: With a particular focus on gender differences, we retrospectively compared clinico-pathological findings between 44 patients (9 men, 35 women) with PBM without biliary dilatation and 232 patients (60 men, 172 women) with gallbladder cancer that was not associated with PBM. Results: Gallbladder cancer was detected in 75% of patients with PBM without biliary dilatation. Among PBM patients, gallbladder cancer was significantly more common in women than in men [29/35 (83%) vs. 4/9 (44%), p<0.05]. Both men and women with gallbladder cancer associated with PBM were significantly younger at the time of diagnosis than patients with gallbladder cancer without PBM (p<0.01). Gallstones were detected in only 10% of women with gallbladder cancer with PBM, while gallstones were detected in 63% of women with gallbladder cancer without PBM (p<0.01). Conclusions: Gallbladder cancer occurs very frequently in patients with PBM without biliary dilatation, and women appear to be at a significantly higher risk than men.