A Real-World, Population-Based Study for the Incidence and Outcomes of Neuroendocrine Neoplasms of Nondigestive, Nonpulmonary Primary

ObjectivesThe aim of this study was to assess incidence and outcomes of neuroendocrine neoplasms (NENs) arising from primary sites other than digestive organs, lung, or thymic gland.MethodsSurveillance, Epidemiology, and End Results database (1975-2016) was accessed, and cases of NENs arising from primary sites other than digestive organs, lung, or thymic gland were reviewed. Overall and cancer-specific survival outcomes for NENs arising from different organs compared with small intestinal NENs were evaluated.ResultsA total of 4405 patients were included in the study. Compared with small intestinal NENs, some NENs arising from uncommon sites in the current study have worse cancer-specific survival (hazard ratio [HR] for genitourinary vs small intestinal NENs, 1.80; 95% confidence interval [CI], 1.44-2.25; HR for gynecological vs small intestinal NENs, 1.88; 95% CI, 1.52-2.33). When the analysis was limited for patients with distant stage only, small intestinal NENs have better outcomes compared with genitourinary and gynecological NENs (HR for genitourinary NENs with distant stage vs small intestinal NENs with distant stage, 1.38; 95% CI, 1.01-1.88; HR for gynecological NENs with distant stage vs small intestinal NENs with distant stage, 2.02; 95% CI, 1.54-2.66).ConclusionsCompared with small intestinal NENs, NENs arising from uncommon sites (such as genitourinary, gynecological) have worse survival outcomes.