Endocrine Abstracts

Introduction: Gigantomastia is a rare condition characterised by excessive benign breast tissue growth that is thought to be a result of elevated physiological levels of circulating hormones (e.g. pregnancy), or an increased sensitivity of the breast tissue to such hormones. Isolated reports describe some medical conditions as precipitants (e.g. systemic lupus erythematosus (SLE)) or drugs (e.g. cyclosporine). Many will proceed to surgical intervention to improve physical and/or psychological suffering.

Case report: A 39-year-old woman of normal weight conceived with in vitro fertilisation therapy after a salpingectomy for ectopic pregnancy. She had well controlled Graves’ disease and SLE on medication. Shortly after her salpingectomy she noted a gradual increase in her breast size, correlating with her monthly cycle, from a brassiere cup size C to a size E at the time of embryo transplantation. During her pregnancy, her breast size continued to increase at such a rate that her brassiere size changed every 3 weeks. Empiric bromocriptine was started at 30 weeks gestation. At 33 weeks she required inpatient admission for mastitis and a urinary tract infection. At 34 weeks her ultrasound showed oligohydramnios, thought to be secondary to her excessive breast tissue, and so she underwent caesarean section. As she chose not to breastfeed bromocriptine was continued. She had an uneventful postoperative recovery and was discharged three days later. She suffered with two further episodes of mastitis within a month of delivery, and was wearing a size N brassiere that was too small for her. She proceeded to surgery with resection of 6.53 kg of breast tissue; histology confirmed benign proliferative change with no atypia.

Conclusion: Gigantomastia is generally a rare, benign condition but is especially disabling to the pregnant woman. Excellent outcomes are generally achieved with surgery. To our knowledge this is the first documented case in a patient with thyroid disease.