Unusual extension of lung cancer into the left atrium via the pulmonary vein.

Four operative cases of lung cancer with intra-atrial extension via the pulmonary vein were reviewed. Three of them had circulatory as well as respiratory symptoms, and their performance status (PS) was extremely poor. In two cases, after assessment of the cardiac involvement using two-dimensional echocardiography and/or CT-scan, we successfully removed the tumor en bloc through combined left atrial resection and radical left pneumonectomy with cardiopulmonary bypass. In both cases, the postoperative course was uneventful, and PS was improved. However, seven months later one patient died of widespread metastases, while the other is alive but has recurrence. The other two patients underwent ordinary lobectomy because there were no abnormal findings in the hilar examinations. However, the lumens of the resected pulmonary veins were filled with tumor tissue. One patient developed a massive embolism, never regained consciousness, and died on the second postoperative day. The last case was discharged without trouble, although the intra-atrial portion of the tumor dislodged intraoperatively into the circulation. As a result, he developed multiple brain metastases four months after the operation. There were no clear patterns in terms of the histological type or tumor location in these cases. On the other hand, all the tumors showed rapid growth and comprised a large mass in the lung parenchyma. Especially the cardiac and intravascular portions of each tumor were less differentiated and more necrotic than the primary focus in the lung. We conclude that radical surgery using a cardiopulmonary bypass for lung cancer patients with such intracardiac involvement is effective for improvement of PS and reduces the risk of sudden death due to cardiac failure or tumor emboli.(ABSTRACT TRUNCATED AT 250 WORDS)