Abstract
A case of gigantomastia is reported. The breast enlargement started some years before first pregnancy, during which a tremendous acceleration was observed. Various laboratory investigations elicited normal values, except for some high values of prolactin. No treatment was given. After delivery, the patient nursed her baby. Thirteen weeks later, lactation was inhibited with bromocriptine. A further 3 weeks later, a reduction mammoplasty was performed. One year later, the prolactin values were still normal. The etiology of this disease is not known. One possible explanation is an increased number or increased sensitivity of prolactin receptors in the target organ.