Time between pancreatic cancer diagnosis and treatment initiation and survival in the U.S. Military Health System.

Abstract

Background: Pancreatic cancer has a high case fatality and treatment is known to improve survival. It is unknown whether the time between diagnosis and treatment initiation (time-to-treatment) is related to survival. Access to medical care may influence both treatment receipt and timing. We examined the relationship between time-to-treatment and survival among patients with pancreatic adenocarcinoma treated in the equal access Military Health System.

Methods: We used the MilCanEpi database to study a cohort of 806 men and women who were diagnosed with stage I-IV pancreatic adenocarcinoma between 1998 and 2014 and received either surgery or chemotherapy as primary treatment. Time-to-treatment in relation to overall survival was examined in multivariable time-dependent Cox regression models.

Results: Overall, median time-to-treatment was 3 weeks and 95 % of patients received treatment within 12 weeks. Time-to-treatment >6 weeks was associated with a statistically significant lower risk of death (AHR = 0.77, 95 % CI = 0.61-0.98) compared to time-to-treatment <3 weeks. Analysis by the first treatment type showed that time-to-surgery was not associated with survival among those receiving upfront surgery. Time-to-chemotherapy of >6 weeks was associated with reduced risks of death compared to <3 weeks (AHR = 0.62, 95 % CI = 0.48-0.80) for patients receiving primary chemotherapy.

Conclusions: Our data suggests that longer time-to-treatment, especially among patients with chemotherapy, was associated with lower risk of death among patients with pancreatic adenocarcinoma who received treatment. Further research is needed to understand the association of intervals along the whole cancer spectrum (e.g., presentation, diagnosis, treatment) and longer treatment intervals (i.e., >12 weeks) with survival.