Eric J Kuo, Ronald R Salem
Objective Studies of pancreatic solid pseudopapillary neoplasms are limited to institutional series. Outcomes and predictors of survival on a population-level remain unclear. Methods Patients with solid pseudopapillary carcinomas of the pancreas were selected from the SEER database (2000-2010), and incidence, characteristics, and survival evaluated. Data were analyzed with χ2 tests, ANOVA, the Kaplan Meier method, log-rank tests, logistic regression, and Cox proportional hazards. Results The diagnosis of SPCs has increased within the last decade. Men had a trend towards larger tumors (7.3 cm vs. 6.2 cm, P=0.282) with higher rates of extrapancreatic extension (37.5% vs. 25.3%, P=0.338), nodal metastasis (25.0% vs. 3.6%, P=0.076) and distant metastasis (18.8% vs. 9.5%, P=0.376) in comparison to women, although the differences failed to reach statistical significance. 5-year disease-specific survival in men was compromised in comparison to women (74.1% vs. 91.7%, P=0.026). After adjustment for age, gender, race, surgery, radiation, tumor location, tumor size, and extrapancreatic extension, nodal metastasis (hazard ratio 41.4, 95% confidence interval 2.3-753.1) and distant metastasis (hazard ratio 9.0, 95% confidence interval 1.8-45.4) remained independent predictors of disease-specific survival. Subset analysis of patients with distant disease revealed a trend towards decreased 5-year disease-specific survival in men in comparison to women (20.0% vs. 71.4%, P=0.072). Conclusions Solid pseudopapillary carcinomas are an increasingly diagnosed entity. Even with malignant disease, prognosis is excellent in women; however, men in the US with solid pseudopapillary carcinomas have compromised survival, possibly due to higher rates of nodal and distant metastasis. Treatment and follow-up strategies should be tailored accordingly.
