Abstract
PURPOSE: Hospital-based clinical studies have limitations in holistic assessment of cancer treatment and prognosis, as they omit out-of-hospital patients including elderly individuals. This study aimed to investigate trends in initial treatment and corresponding prognosis of patients with exocrine pancreatic cancer (EPC) in Korea. MATERIALS AND METHODS: The Korea Central Cancer Registry data of patients with EPC from 2006 to 2017 were retrospectively reviewed. We defined the first course of treatment (FT) as the cancer-directed treatment administered within four months after cancer diagnosis according to the Surveillance, Epidemiology, and End Results (SEER) program. RESULTS: Among 62,209 patients with EPC, localized and regional (LR) SEER stage; patients over 70 years old; and ductal adenocarcinoma excluding cystic or mucinous (DAC) accounted for 40.6%, 50.1%, and 95.9%, respectively. "No active treatment" (NT, 46.5%) was the most frequent, followed by non-surgical FT (28.7%) and surgical FT (22.0%). Among 25,198 patients with LR EPC, surgical FT increased (35.9% to 46.3%) and NT decreased (45.0% to 29.5%) from 2006 to 2017. The rate of surgical FT was inversely related to age (55.1% [< 70 years], 37.3% [70-79 years], 10.9% [≥ 80 years]). Five-year relative survival rates of LR DAC were higher after surgical FT than after NT in localized (46.1% vs. 12.9%) and regional stage (23.6% vs. 4.9%) from 2012 to 2017. CONCLUSION: Less than half of overall patients with LR EPC underwent surgical FT, and this proportion decreased significantly in elderly individuals. Clinicians should focus attention on elderly patients with EPC to provide appropriate medical advice.