Familial juvenile hypertrophy of the breast (JHB) is a rare condition characterized by gigantomastia in peripubertal females. The pathology is limited to the breast with otherwise normal growth and development (summary by Genzer-Nir et al., 2010).
... Familial juvenile hypertrophy of the breast (JHB) is a rare condition characterized by gigantomastia in peripubertal females. The pathology is limited to the breast with otherwise normal growth and development (summary by Genzer-Nir et al., 2010). A syndrome has been described in which affected females display JHB in association with onychodystrophy/anonychia and abnormalities of the distal phalanges (ODP; see 106995), whereas males have only ODP (mammary-digital-nail syndrome; 613689).
Badejo (1984) observed unilateral giant breast in 4 of 7 female children from 2 unrelated families in Nigeria. Males were unaffected. All 4 affected females noted the development around age 8 years, which resulted in great social embarrassment ... Badejo (1984) observed unilateral giant breast in 4 of 7 female children from 2 unrelated families in Nigeria. Males were unaffected. All 4 affected females noted the development around age 8 years, which resulted in great social embarrassment throughout their lives. Unilateral breast enlargement was suspected in the 4-year-old child of an affected female. Three of the women had breast reduction surgery, and histology showed no evidence of malignancy. One of the patients developed hypertrophy of the other breast after surgery. The condition had been described before by surgeons in Africa who attributed it to lymphedema or considered it to be related in part to pregnancy. However, onset occurred well before pregnancy in this study. Badejo (1984) suspected that the father in each family might be a carrier of a sex-limited autosomal dominant gene. Kupfer et al. (1992) reported a mother and daughter with the condition. The mother developed rapid massive enlargement of both breasts at age 11 years. As a consequence, she developed kyphosis and lordosis necessitating breast reduction surgery. Histologic examination showed hyperplasia of stromal and epithelial elements. Her daughter developed similar bilateral massive breast enlargement following normal menarche at age 11.5 years. Kupfer et al. (1992) provided a review of the literature and stated that 29 cases had been reported, including their 2. Juvenile hypertrophy of the breast was characterized by rapid, bilateral, and often asymmetrical enlargement of the breasts in the peripubertal period. The pathologic mechanism was postulated to represent an end-organ hypersensitivity to normal estrogen stimuli. Misirlioglu and Akoz (2005) reported 2 affected adult sisters who had onset of the disorder in adolescence. Dancey et al. (2008) provided a review of gigantomastia and proposed a classification scheme based on the cause, management, and prognosis of the disease. Among a total of 115 patients gleaned from the literature and their practice, the authors identified 57 as having juvenile gigantomastia. The juvenile form was considered to be distinct from pregnancy-induced gigantomastia, although both forms likely result from aberrant endogenous hormone stimulation.