Advanced intravascular bronchioloalveolar tumour and review of reports in Japan.

Intravascular bronchioloalveolar tumour (IVBAT) is a rare pulmonary neoplasm. We report the clinical and pathologic findings of two patients who demonstrated unusual clinical features. Both of them were young males who showed a large mass or consolidated shadow and small nodules with pleurisy on chest X-rays due to the invasive growth of tumours. In the first case the presumptive diagnosis of lung carcinoma was made from the discovery of atypical cells in pleural fluid. In the second case pleural mesothelioma was suspected. However, the histological diagnoses of these cases, including the immuno-histological and ultrastructural data, were reported and clinical features of IVBAT described previously in Japan were summarized.