Unilateral Breast Enlargement
Breast enlargement associated with carcinoma of the lung is most commonly a paraneoplastic manifestation of non-small cell carcinoma. Hormonally mediated proliferation of the glandular component of the breast leads to unilateral or bilateral enlargement. This report describes a patient with small cell carcinoma of the lung who presented with unilateral breast enlargement related to superior vena cava obstruction.

Male breast enlargement may be unilateral or bilateral and can occur as benign enlargement caused by glandular proliferation or gynecomastia, or as a manifestation of an underlying local process. There are several well-described mechanisms for breast enlargement in lung cancer. The most common type of lung cancer is non-small cell carcinoma (SCC) of the lung. Superior vena cava (SVC) syndrome presenting as unilateral breast enlargement is rarely described. In this report, we describe a patient with SCC of the lung who presented with unilateral breast enlargement related to SVC obstruction.