Anterior mediastinoscopy for evaluation of mediastinal metastases of cancer of the left lung.

In 20 of 62 patients (32%) with presumably operable cancer of the left lung, metastatic cancer in the anterior mediastinal lymph node was detected by left anterior mediastinoscopy without division or spreading of costal cartilage. Fourteen of 41 patients (33%) with left upper lobe and four of 19 (21%) with left lower lobe cancer had positive anterior mediastinal node biopsies. In a comparable group having cervical mediastinoscopy for cancer of the right lung, 39 of 103 (38%) had positive paratracheal or subcarinal lymph nodes. In both mediastinoscopy groups six of 45 squamous carcinomas (13%), 28 of 72 adenocarcinomas (39%), and 25 of 48 undifferentiated carcinomas (52%) had positive mediastinal nodes. Hilar neoplasms were associated with positive mediastinal nodes in 35 of 52 patients (67%) and peripheral neoplasms in only 25 of 113 patients (22%). Thirty-nine of 42 patients (93%), after negative anterior mediastinoscopy in left lung cancer, had resectable tumors and 59 of 64 (92%) had resectable tumor after negative cervical mediastinoscopy in right lung cancer.