Unilateral gynecomastia associated with thoracotomy following resection of carcinoma of the lung.

A 66-year-old man developed right painful gynecomastia following resection of a well-differentiated squamous cell carcinoma from the right upper lobe. In 1979, he had a well-differentiated squamous cell carcinoma resected from the left lower lobe. Extensive investigation did not reveal any definite indication of metastases or residual carcinoma. There was no evidence for thyroid, liver, or renal disease. His plasma testosterone was 400 ng/dl, estradiol was 43 pg/ml, LH 3.5 ng/ml, FSH 13.1 mIU/ml and HCG less than 5 mIU/ml. Since no other cause of gynecomastia was apparent , it was attributed to the right thoracotomy.