Multinucleated stromal giant cells in adolescent gynaecomastia

Bizzare multinucleated stromal giant cells were observed in a case of adolescent gynaecomastia. Similar cells have been described in the female breast in both benign and malignant conditions where they are thought to originate either from reactive stromal cells or from the mononuclear phagocyte system, respectively. Immunohistochemistry and electron microscopy in this case support the idea that they originate from stromal fibroblasts. Their occurrence in gynaecomastia is further evidence that these changes in stromal cells may be due to hormonal influences.