Unmasking the silent killer: The hidden aggressiveness of signet-ring cell carcinoma in gallbladder cancer.

The prognostic significance of the signet-ring cell component in gallbladder carcinoma (GBC) has not been systematically evaluated. The aim of this study was to assess the similarities and differences between gallbladder signet-ring cell carcinoma (GBSRCA) and gallbladder adenocarcinoma (GBAC) in terms of clinicopathological features and long-term survival. Using the Surveillance, Epidemiology, and End Results (SEER) database, we analyzed 6,612 patients diagnosed with gallbladder cancer between 2000 and 2021. The cohort included 147 patients with GBSRCA and 6,465 with GBAC. Patients with GBSRCA were significantly younger, with 33.3% being age 60 or younger compared to 23.9% of patients with GBAC (p = 0.009). There was a higher proportion of females in the GBSRCA group (77.6%) compared to the GBAC group (70.1%, p = 0.049). GBSRCA was associated with a more advanced tumor stage (T3-T4: 56.5% vs. 44.4%, P = 0.004), higher rates of lymph node metastasis (43.5% vs. 28.0%, P < 0.001), and poorer differentiation status (poorly to undifferentiated: 80.3% vs. 29.7%, P < 0.001). Survival analysis revealed that patients with GBSRCA had significantly worse overall survival (OS) and cancer-specific survival (CSS) compared to patients with GBAC (p < 0.001). GBSRCA was an independent prognostic factor for OS (P = 0.001) in the entire cohort, while the T stage and N stage were independent prognostic factors for OS and CSS in patients with GBSRCA. Even after propensity score matching, patients with GBSRCA still had a poorer prognosis.