In the United States, pancreatic cancer incidence has increased for both men and women over the last 20 years [1]. The most common type of pancreatic cancer is pancreatic ductal adenocarcinoma. Unfortunately, pancreatic cancers have a high case fatality rate with five-year survival rates not exceeding 10 % [2], [3]. Understanding the treatment of the disease and its association with outcomes is paramount to improving the prognosis for patients diagnosed with pancreatic cancer.

Pancreatic cancer treatment is directed by recognized guidelines [4], [5], [6]. Eighty percent of patients with pancreatic adenocarcinoma have locally advanced or metastatic disease at diagnosis and are generally considered poor candidates for surgery [3], [6]. These patients may be recommended chemotherapy as primary treatment [4], [6]. Specifically, palliative treatment with multi-agent chemotherapy is the standard of care for patients with metastatic pancreatic adenocarcinoma [4]. Surgery, often as a palliative procedure, may be offered to patients with advanced pancreatic cancer. About 20 % of patients with pancreatic adenocarcinoma have localized disease and may be eligible for surgery at diagnosis [3], [4], [5]. Current guidelines recommend surgery as the primary treatment for localized pancreatic cancer with either neoadjuvant or adjuvant chemotherapy as tolerated [2], [4], [5], [7]. Surgery is considered the only potentially curative treatment for localized pancreatic cancer, so treatment with chemotherapy alone is not recommended [4], [5].

The pancreatic cancer treatment guidelines were established primarily based on the research results from clinical trials [4], [5]. Only recently are population-based studies on standard treatment(s) (i.e., surgery and chemotherapy) and effects on overall and cancer-specific survival emerging [8], [9]. For a population-based study, accessibility to medical care often influences cancer treatment [10], [11]. Furthermore, access to care may vary across socio-demographic groups, further complicating the relationship between cancer treatment(s) and survival in the U.S. population [11]. Thus, studying pancreatic cancer treatment and survival in a health system where patients are provided access to care regardless of medical conditions or socio-demographic attributes may provide important information on the topic.

The U.S. Military Health System (MHS) provides comprehensive access to medical care to over 9.6 million Department of Defense (DoD) beneficiaries, which include active-duty service members, activated National Guard, retirees from active service, and their dependents; at little to no out-of-pocket cost [12]. In the MHS, we can study cancer care delivery while minimizing the financial and access barriers to receiving treatment historically observed in the general U.S. population [10], [11]. We aimed to assess treatment type and its relationship to overall survival in patients with pancreatic adenocarcinoma receiving care in the MHS to provide more evidence on the effectiveness of treatment from a healthcare setting that offers comprehensive medical care to its beneficiaries.