Evolving features of lung adenocarcinoma in Rio de Janeiro, Brazil.

Formerly considered rare, adenocarcinoma has become the commonest form of primary lung cancer in developed countries. Its clinical presentation has changed, with central tumors becoming more frequent. We reviewed all biopsies with a diagnosis of primary lung cancer obtained from October 1988 to April 1997 in a tertiary care hospital in Rio de Janeiro. Medical records from adenocarcinomas were analysed. Adenocarcinoma was the commonest form of lung cancer (168/409, 41%). Central tumors were observed in 43% according to radiological criteria and 47% according to bronchoscopic criteria. The frequency and clinical presentation of adenocarcinoma have evolved lately in Rio de Janeiro.