EFFECT ON PROGNOSIS OF BONE-MARROW INFILTRATION DETECTED BY MAGNETIC-RESONANCE-IMAGING IN SMALL-CELL LUNG-CANCER

The staging system of limited disease (LD) and extensive disease (ED) is widely used and has been shown to provide useful prognostic informa tion in cases of small cell lung cancer (SCLC). However, accurate exam inations are necessary for correct staging. In this report, we evaluat ed the clinical usefulness of magnetic resonance imaging (MRI) of bone marrow in SCLC. 37 patients with LD by standard staging and 41 with E D were examined with bone marrow MRI. Results of bone marrow MRI did n ot influence the choice of treatment in patients with LD. For subseque nt analysis, patients with LD were divided into two groups: patients i n whom bone marrow infiltration was detected with MRI (MRI-positive LD group) and those in whom it was not (MRI-negative LD group). Focal or diffuse metastases to bone marrow were detected with MRI in 46% (36/7 8) of all patients and 35% (13/37) of LD patients. The response rates to treatment in patients with MRI-positive LD were lower than those in patients with MRI-negative LD (P = 0.006). The survival of patients w ith MRI-positive LD was worse than that of MRI-negative LD (generalise d Wilcoxon test: P = 0.0157), and closer to that of ED. Multivariate a nalyses using a Cox model that included the result of bone marrow MRI, performance status, chemotherapy regimen, radiotherapy and serum lact ose dehydrogenase (LDH) level showed that the result of bone marrow MR I remained a prognostic factor in SCLC patients with limited disease. Bone marrow examination with MRI is useful for better staging of SCLC. According to our analysis of response rates and survival, MRI-positiv e LD should be considered a type of ED. (C) 1997 Elsevier Science Ltd.