Tumorlets, multicentric carcinoids, lymph-nodal metastases, and long-term behavior in bronchial carcinoids.

BACKGROUND: The clinical significance of lymph-node metastases, multicentric forms, and tumorlets in bronchial carcinoids is still a matter of debate. Aim of this study was to analyze their prevalence and clinical significance in a series of 123 bronchial carcinoids.

PATIENTS AND METHODS: Nodal dissection and serial sections of resected lung parenchima for research of multicentric forms and tumorlets were performed in most patients. Survival curve was produced using the Kaplan-Meyer method and multivariate analysis by the Cox proportional hazard model.

RESULTS: Lymph-node involvement was present in 14% of typical (14 of 100) and 13.04% of atypical carcinoids (3 of 23). Multicentric forms (syncronous carcinoids or tumorlets) were found in 11.3% of the total with a negative impact on survival (p = 0.021). Multiple tumorlets were found in 7.3% of all cases at the standard pathologic examination, but whenever accurate palpation and serial sections of the surgical specimen were performed, the percentage reached 24% of the cases. Overall survival was 98.2%, 95.8%, and 83.9% for typical and 71.6%, 57.3%, and 24% for atypical carcinoid respectively at 5, 10, and 15 years. Time from surgery was significantly directly correlated with recurrences (p < 0.0001) and disease related death (p = 0.0002).

CONCLUSIONS: A high prevalence of tumorlets, multiple carcinoids, and lymph-nodal involvement was found in our series. On the basis of these observations bronchial carcinoids always require major surgical procedures with systematic nodal dissection, and a careful search for multifocal lesions should always be performed. Follow-up should always be accurate and protracted, due to the frequency of very long-term relapses (often more than 10 years after surgery).