A population-based study of incidence and patient survival of small cell carcinoma in the United States, 1992–2010

摘要

Background In contrast to the well-described epidemiology and behavior of small cell lung carcinoma (SCLC), little is known about extrapulmonary small cell carcinoma (EPSCC). Methods Using data from the Surveillance, Epidemiology and End Results (SEER) Program (1992–2010), we calculated age-adjusted incidence rates (IRs), IR ratios (IRRs), annual percent change (APC), relative survival (RS), RS ratios (RSRs), and the respective 95% confidence intervals (95% CI) of SCLC and EPSCC according to primary site. We used the SEER historic stage variable that includes localized (confined to the organ of origin), regional (direct extension to adjacent organ/tissue or regional lymph nodes), and distant (discontinuous metastases) stages and combined localized and regional stages into “limited” stage. Results The incidence of SCLC (IR?=?76.3/million person-years; n?=?51,959) was 22-times that of EPSCC (IR?=?3.5; n?=?2,438). Of the EPSCC sites, urinary bladder, prostate, and uterine cervix had the highest incidence (IRs?=?0.7-0.8); urinary bladder (IRR?=?4.91) and stomach (IRR?=?3.46) had the greatest male/female disparities. Distant-to-limited stage site-specific IRRs of EPSCC were significantly elevated for pancreas (IRR?=?6.87; P?Conclusion EPSCC comprises a heterogeneous group of diseases that appears, at least in part, etiologically distinct from SCLC and is associated with more favorable stage-specific patient survival.