[Serum and pleural SCC-antigen levels in patients with pulmonary tuberculosis].

We measured the serum and pleural levels of squamous cell carcinoma related antigen (SCC-Ag) in patients with active pulmonary tuberculosis and studied the relationship between SCC-Ag and tuberculosis. Serum levels of SCC-Ag in 63 patients with newly diagnosed untreated tuberculosis were 1.76 +/- 2.16 ng/ml, significantly higher than in 118 healthy controls (0.67 +/- 0.52 ng/ml) or in 11 patients with old tuberculosis (0.92 +/- 0.38 ng/ml; p < 0.01). Pleural effusion levels of SCC-Ag in 41 patients with tuberculosis pleurisy were 4.5 +/- 3.4 ng/ml, significantly higher than in 54 patients with non-malignant, non-tuberculous, pleurisy (2.3 +/- 1.7 ng/ml: p < 0.05). In patients who responded well to anti-tuberculous chemotherapy, serum levels of SCC-Ag decreased to the normal range (1.6 ng/ml) with clinical improvement, while in nonresponders they did not decrease. Isoelectolic focusing electrophoresis showed serum SCC-Ag to be composed of a neutral fraction as a single peak, which was corresponded to that of squamous cell carcinoma of the lung. The tuberculous lesions were stained with anti-SCC-Ag antibody in one case and weak SCC-Ag positive findings were observed in the intercellular spaces of the epidermoid cells in the area without necrosis. These results raise the possibility that SCC-Ag is produced in or released from not only squamous cell carcinoma of the lung but also pulmonary tuberculous lesions.