Prognostic Impact of Unplanned Hospitalization During First-Line Gemcitabine Plus Nab-Paclitaxel Therapy for Unresectable Pancreatic Cancer: A Single-Center Retrospective Observational Study

Background: Pancreatic cancer (PC) is a refractory malignancy with a dismal prognosis. For unresectable PC, gemcitabine plus nab-paclitaxel (GnP) is widely used as first-line chemotherapy. During treatment, patients may require unplanned hospitalization (UPH) due to tumor progression, biliary obstruction, or chemotherapy-related adverse events. Although UPH during chemotherapy may be linked to poorer survival, its prognostic impact as a time-dependent clinical event during active treatment has not been empirically evaluated in unresectable PC. We investigated the prognostic impact of UPH occurring during first-line GnP therapy. Objective: To clarify the association between UPH during first-line GnP and overall survival (OS). Methods: We retrospectively analyzed 189 patients with histologically confirmed unresectable PC who received first-line GnP at our institution between February 2016 and February 2023. The occurrence of UPH during GnP and the reason for the first UPH were categorized. Associations with OS were assessed using the Kaplan–Meier method and Cox proportional hazards models, including a time-varying covariate (TVC) analysis. Risk factors for UPH were examined with logistic regression. Results: UPH occurred in 76 patients (40.2%) during GnP. Pancreatic head tumors and pre-treatment biliary drainage were significantly more frequent in the UPH group. Median OS was 10.88 months in the UPH group versus 19.23 months in the non-UPH group; UPH was a significant adverse prognostic factor (hazard ratio [HR] 1.97, p < 0.01). In multivariable analysis incorporating a TVC, UPH remained an independent predictor of worse prognosis (HR 3.02, p < 0.01). Reasons for first UPH were progression (n = 28), recurrent biliary obstruction (RBO; n = 26), GnP-related adverse event (AE; n = 16), and other (n = 6). Hospitalization due to progression or RBO was associated with poorer survival. Pancreatic head location was identified as a risk factor for UPH. Conclusions: UPH during first-line GnP is an independent adverse prognostic factor in patients with unresectable PC, even after accounting for TVC. In pancreatic head cancer, closer monitoring for biliary and obstructive complications may be particularly important during treatment.