General features
(1) an absence of glandular or ductal tissue
proliferation on physical exam, mammography and histology
(2) identification of an infiltrative process causing the mass
(2a) fat accumulation (see below)
(2b) soft tissue tumors (see below)
(2c) benign skeletal muscle (see below)
(2d) fibroinflammatory process (see below)
NOTE: Pseudogynecomastia tends to be used for a benign process. Carcinoma of the male breast is viewed as a separate process.
Fat accumulations:
(1) associated with obesity (lipomastia)
(2) lipoma
(3) lipodystrophy (AIDS, diabetes, etc.)
Soft tissue tumors:
(1) neurofibromatosis
(2) lymphangioma or other vascular tumor
Fibroinflammatory process:
(1) repeated blunt trauma to the breast
(2) repeated occupational trauma to the chest
(3) self-injection (heroin, other drugs)
