MICROMETASTATIC TUMOR-CELLS IN THE BONE-MARROW OF PATIENTS WITH NONSMALL CELL LUNG-CANCER

Background. This study was designed to evaluate the incidence and clin ical implications of detection of micrometastatic cancer cells in bone marrow aspirates of patients with operable non-small cell lung cancer . The relationship between micrometastatic cells and p53 overexpressio n in the primary tumor was also assessed. Methods. Thirty-nine patient s with stages I through III non-small cell lung cancer who underwent c urative resection were entered into this study. Immunohistochemistry w ith monoclonal antibody to cytokeratin 18 was used to detect tumor cel ls in bone marrow. Immunostaining of p53 protein in the corresponding primary tumors was also done. Results. Cytokeratin 18-positive cells w ere detected in 15 (39%) of the 39 patients. Overexpression of p53 was associated with positivity of the tumor cells in the bone marrow at b orderline significance (14/29 versus 1/10; p = 0.0574). The patients w ith cytokeratin 18-positive cells in bone marrow demonstrated a signif icantly earlier recurrence than those without such cells (p = 0.0083, log-rank test). Conclusions. Micrometastatic cancer cells were frequen tly present in bone marrow of patients with operable non-small cell lu ng cancer and may be a significant predictor of early recurrence. Furt her evaluation of this method may be useful in identifying patients wi th nonsmall cell lung cancer who are most likely to benefit from adjuv ant chemotherapy. (C) 1997 by The Society of Thoracic Surgeons.