Introduction: Solid pseudopapillary tumors (SPT) are rare, slow growing tumors of the pancreas that typically affect young women. Surgical resection is known to offer excellent long term survival. Due to rarity of the disease, most data on SPT are derived from case reports and small case series. To provide more insight into the epidemiology, treatment, and outcomes of these patients, we reviewed data from patients with SPT in the Surveillance, Epidemiology and End Results (SEER) database.
Methods: Patients with SPT were identified from the SEER database using the International Classification of Disease for Oncology, 3rd edition histology codes for SPT (8452/3), with pancreas (C25.0-C25.9) listed as the primary disease site. We collected data on patient demographics, year of diagnosis, primary tumor site, histology, surgery and survival until death or last follow up for the period 1973-2014. Survival was plotted using Kaplan-Meier curves. Hazard ratios were obtained and survival was compared using univariate Cox proportional hazard models.
Results: Overall, 186 patients were identified. The mean (SEM) follow up time was 57.5 (3.66) months. Majority (82.3%) of the study population was female. The median (range) age of the study population was 36.5 (8-82) years. Tumors were most frequently located in the body/tail (67.3%). Stage IV disease at presentation was uncommon (9.9%) and most (84.4 %) patients underwent surgical resection (Table 1). The 5-year survival for the cohort was 90.3%. On univariate analyses, age >50 years (HR 3.77, p=0.0065), male sex (HR 4.12, p=0.0029) and not receiving surgery (HR 9.2, p<0.0001) were associated with worse survival. Disease stage (IV vs other stages) and tumor location (head vs body/tail) did not impact survival.
Conclusion: In this large population-based series on SPT, we conclude that atypical features such as age >50, male sex and non-operative management are significantly associated with reduced survival in these patients.