PURPOSE: Pulmonary atypical carcinoid (AC) and typical carcinoid (TC) tumors are in the bronchopulmonary neuroendocrine tumor (BPNET) classification that includes large-cell neuroendocrine carcinoma (LCNEC), and small cell lung cancer (SCLC). Previous small studies suggest that resected pulmonary AC has a clinical presentation and survival pattern distinct from TC. For patients undergoing pulmonary lobectomy, we hypothesized: 1) resected pulmonary TC will show a favorable clinical presentation and survival pattern compared to other BPNETs, and 2) AC and LCNEC patients will have similar clinical outcomes.
METHODS: The Surveillance Epidemiology and End Result database was queried to compare demographic (age, gender, ethnicity) and tumor specific clinical variables (including nodal status and stage) in 2239 patients undergoing lobectomy for TC, 145 for AC, 510 for LCNEC and 1521 for SCLC from 2001 to 2006. We analyzed differences in clinical variables and survival among the BPNET histologic types.
RESULTS: AC patients presented at a similar age of diagnosis (Mean 59.9 years) as TC (Mean age 58.5) but much younger than LCNE and SCLC (Mean age of 65.3 and 66.2 respectively, P < 0.001). AC and TC had much higher predilection towards female patients (70.3%, 68.7%) than LCNE and SCLC (45.7% and 51.4%, p < 0.001). Similar to LCNEC, AC patients had greater incidence of histologic positive lymph nodes and higher pathologic stage compared to TC (p < 0.001). Survival analysis showed a mean survival of 40.0 ± 1.9 months for SCLC, 46.2 ± 2.2 months for LCNEC, 58.3 ± 2.3 months for AC, and 70.2 ± 0.2 months for TC tumors. TC patients demonstrated favorable survival, and SCLC patients poorer survival, compared to AC and LNEC patients.
CONCLUSION: TC and SCLC tumors are BPNET histologies that exhibit clinical behavior distinct from AC and LCNEC, including greater incidence of positive lymph nodes and higher pathologic stage, as well as similar survival.
CLINICAL IMPLICATIONS: AC tumors should be staged, and treated with stage appropriate neoadjuvant and adjuvant therapeutic strategies similar to LCNE and other non-small cell lung cancers.
DISCLOSURE: Jay Bhatt, No Financial Disclosure Information; No Product/Research Disclosure Information