Impact of time from diagnosis to chemotherapy on prognosis in advanced pancreatic cancer

Background: Due to the aggressive nature and poor prognosis of advanced pancreatic cancer, prompt initiation of treatment is critical. We investigated the effect of the interval between cancer diagnosis and initiation of chemotherapy on survival in patients with advanced pancreatic cancer. Methods: In this retrospective, single-centre study, consecutive patients with advanced pancreatic cancer between April 2013 and March 2022 were analyzed. Data were extracted from the electronic medical records of patients who received chemotherapy for metastatic, locally advanced or resectable pancreatic cancer or who received chemotherapy due to either being intolerant of or declining surgery. We compared overall survival between two groups: the early waiting time group (waiting time <= 30 days from diagnosis to chemotherapy initiation) and the elective waiting time group (waiting time >= 31 days). Prognostic factors, including biliary drainage, were considered. The impact of waiting time on survival was assessed by univariate and multivariate analyses with Cox proportional hazard models. A 1:1 propensity score matching approach was used to balance bias, accounting for significant poor prognosis factors, age and sex. Results: The study involved 137 patients. Overall survival exhibited no statistically significant difference between the early and elective waiting time groups (207 and 261 days, P = 0.2518). Univariate and multivariate analyses identified poor performance status and metastasis presence as predictors of worse prognosis. This finding persisted post propensity score matching (275 and 222 days, P = 0.8223). Conclusions: Our study revealed that initiating chemotherapy >30 days later does not significantly affect treatment efficacy compared to within 30 days of diagnosis.