Association of time interval between cancer diagnosis and initiation of palliative chemotherapy with overall survival in patients with unresectable pancreatic cancer

INTRODUCTION: Palliative chemotherapy is the standard treatment for patients with unresectable pancreatic cancer. Whether the early initiation of palliative chemotherapy is associated with a favorable survival outcome for these patients is not known. This study aimed to analyze the association of the time interval between cancer diagnosis and initiation of palliative chemotherapy with survival outcome in patients with pancreatic cancer. METHOD: A total of 838 patients with unresectable pancreatic cancer who underwent palliative chemotherapy from 2010 to 2016 at 4 institutions in Taiwan were retrospectively enrolled. All patients were categorized according to time interval between cancer diagnosis and initiation of palliative chemotherapy for comparison of the survival outcome. RESULT: The median time interval was 14 days (range, 0 to 163 days) in our patient cohort. Accordingly, 22%, 29%, and 49% of the patients underwent palliative chemotherapy within 1, 1 to 2, and >2 weeks after cancer diagnosis, respectively. The survival outcome had no statistical difference among these 3 patient groups. Subgroup analyses revealed that patients with the time interval ≤2 weeks exhibited poorer survival outcome than those with the time interval >2 weeks if they initially presented with jaundice (6.1 months vs 8.4 months, P = 0.029). In contrast, patients with the time interval ≤2 weeks revealed a better survival outcome than those with the time interval >2 weeks if they initially presented with pain (8.0 vs 6.3 months, P = 0.014). CONCLUSION: In our study, time interval between cancer diagnosis and the initiation of palliative chemotherapy >2 weeks was not associated with a poorer survival outcome for patients with unresectable pancreatic cancer. Our result might help clinicians to clarify that early initiation of palliative chemotherapy might provide survival benefit for patients who present with tumor pain, but not for those who present with jaundice.