Comparison of computed tomography and 57Co-bleomycin scintigraphy in staging the mediastinal lymph nodes of patients with non-small-cell lung cancer.

The value of computed tomography (CT) and of 57Co-bleomycin scintigraphy (57Co-BLM) in staging the mediastinal lymph nodes was compared in 28 patients suffering from non-small-cell lung cancer. The results were assessed against the pathological findings obtained during thoracotomy or mediastinoscopy. CT staging of the mediastinum had a sensitivity of 75%, a specificity of 80%, an accuracy of 79%, a positive predictive index of 60% and a negative predictive index of 89%. 57Co-BLM scintigraphic staging had a sensitivity of 43%, a specificity of 94%, an accuracy of 80%, a positive predictive index of 75% and a negative predictive index of 81%. In this small series these differences were not statistically significant; it thus appears that CT and 57Co-BLM are of equal value in staging the mediastinum. Mediastinoscopy is not contributory in case of a negative CT or 57Co-BLM. A positive CT or 57Co-BLM, however, indicates the need for histological verification of the mediastinal findings.