Is bone marrow examination in small-cell lung cancer really necessary?

Of 403 patients with small-cell lung cancer, we identified by aspiration, biopsy, or both 67 with bone marrow involvement and found the two procedures to be complementary in detecting marrow involvement. The mean surface area of the positive biopsy specimens was significantly greater than that of a randomly selected group of negative biopsy specimens, suggesting that the larger the specimen, the greater the chance of detecting tumour. Patients with marrow involvement had only a slightly worse prognosis compared with other patients who had extensive disease. Only 7 of the 403 patients (1.7%) had extensive disease based on marrow involvement alone. Because bone marrow examination rarely changes the stage of cancer in noninvasively assessed patients, and has no impact on the tolerance of chemotherapy and only a small effect on length of survival, we do not recommend this procedure in the routine staging of small-cell lung cancer.