Bone marrow micrometastasis might not be a short-term predictor of survival in early stages non-small cell lung carcinoma

Objective: To determine the presence of occult micrometastasis (OM) in a se lected population of surgically resectable patients presenting with non-sma ll cell lung carcinoma (NSCLC) and to evaluate its prognostic value on rela pses and survival. Methods: From February 1996 to December 1999, 99 patient s undergoing surgical treatment for NSCLC were prospectively investigated f or the presence of occult bone marrow micrometastasis. Tumor cells were det ected with monoclonal primary antibodies directed against low molecular wei ght cytokeratins. Results: Median follow-up time was 14.3 months (range 0.2 -45.6 months). Overall prevalence of OM was 22.2% (22 out of 99). The prese nce of OM was not correlated to pathology, T status, or N status. In surviv al analysis, the only independent predictors of overall survival were NO st atus and Stage I (P=0.016 and 0.004, respectively), while T1 was a predicto r of disease-free survival (P=0.044). Metastasis and loco-regional recurren ce were observed at follow-up in 18.2 (four out of 22) and 9% (two out of 2 2) of patients OM(+) and in 14.3 (11 out of 77) and 7.8% (six out of 77) of patients OM(-), respectively (P=not significant). OM was a predictor neith er of overall survival nor of disease-free survival (P=0.52 and 0.97, respe ctively). In Stage I patients, 1-year overall survival and 1-year disease-f ree survival were 89 and 98% for OM(-) patients and 88 and 90% for OM(+) pa tients, respectively (P=0.57 and P=0.75). Conclusions: OM was present in >2 0% of surgically treated NSCLC patients and did not correlate to pathologic al variables. In contrast to previous published data, in this study the pre sence of OM had no influence on overall or disease-free survival. (C) 2001 Elsevier Science B.V. All rights reserved.