BACKGROUND.
Survival improvements have been demonstrated for patients with bronchioloalveolar (BAC) nonsmall cell lung cancer (NSCLC) with intrapulmonary satellite T4 nodules compared with other patients with stage IIIB disease, and for ipsilateral intrapulmonary M1 tumors versus contralateral or distant metastasis. However, it is not known whether these differences are observed in patients with nonâBAC NSCLC.
METHODS.
A caseâonly analysis of the U.S. Surveillance, Epidemiology, and End Results (SEER) data (1999â2003) was conducted. Overall survival (OS) and lung cancerâspecific survival (LCSS) univariate analyses were conducted using the KaplanâMeier method. Multivariate survival analyses were performed using Cox proportional hazards ratios.
RESULTS.
A total of 27,435 incident cases of histologically confirmed, advanced stage NSCLC were identified. Cases with stage IIIB NSCLC due to multiple lesions in the same lobe (n = 633) had a significantly improved median OS (21 months) and LCSS (31 months) compared with other cases with stage IIIB NSCLC (n = 7695), with an OS of 7 months and an LCSS of 9 months (P < .0001 for both comparisons). Among cases with stage IV NSCLC, those with intrapulmonary nodules (n = 3010) had a significantly improved median OS (9 months) and LCSS (10 months) compared with those with distant metastasis (n = 16,097), with an OS of 4 months and an LCSS of 5 months (P < .0001 for both comparisons). These survival differences persisted after adjustment for age, sex, ethnicity, surgery, and radiotherapy. Among cases with stage IV NSCLC, those with ipsilateral intrapulmonary nodules (n = 1120) had improved OS (12 months) compared with those with bilateral intrapulmonary nodules (n = 1890), with an OS of 7 months (P < .0001).
CONCLUSIONS.
Cases with stage IIIB and IV NSCLC with ipsilateral intrapulmonary nodules were found to have improved survival outcomes compared with other cases with stage IIIB and IV disease. The results of the current study add additional support for modifications to the current NSCLC staging system. Cancer 2008. © 2007 American Cancer Society.