Myxoid fibroadenoma and allied conditions (myxomatosis) of the breast. A heritable disorder with special associations including cardiac and cutaneous myxomas

Am J Surg Pathol. 1991 Aug;15(8):713-21. doi: 10.1097/00000478-199108000-00001.


Among 145 patients with the complex of myxomas, spotty pigmentation, endocrine overactivity, and psammomatous melanotic schwannomas, 31 (21%) had mammary lesions. The ages of these 26 females and five males ranged from 6 to 64 years (mean, 30 years). Five patients had breast symptoms. In 21 (81%) of the females, benign mesenchymal lesion(s) were detected pathologically. These were characterized by accumulations of large amounts of ground substance in the lobules that alterated the stroma to a very loose and myxoid tissue. The change involved single lobules (lobular myxoid change), small groups of lobules (nodular myxoid change), and large aggregates of lobules (myxoid fibroadenoma); the interlobular stroma was affected to a lesser degree. The lesions were multicentric and bilateral in eight patients (38%). Because the myxoid breast lesions were familial, were frequent findings in the complex, and were similar histologically to the cardiac and cutaneous myxomas in the complex, they undoubtedly are a component and a pathologic marker of the complex. They were the presenting feature of the complex in six patients (19%). Therefore, discovery of the myxoid breast lesions on pathologic examination should raise suspicion of the complex, and affected patients (and their primary relatives) should be evaluated accordingly.

MeSH terms

  • Adenofibroma / pathology*
  • Adenofibroma / surgery
  • Adolescent
  • Adult
  • Breast Neoplasms / pathology*
  • Breast Neoplasms / surgery
  • Child
  • Child, Preschool
  • Cushing Syndrome / pathology
  • Family Health
  • Female
  • Heart Neoplasms / pathology*
  • Humans
  • Lentigo / pathology
  • Male
  • Mastectomy
  • Melanoma / pathology
  • Middle Aged
  • Myxoma / pathology*
  • Neoplasms, Multiple Primary / pathology*
  • Neuroma / pathology
  • Skin Neoplasms / pathology*
  • Syndrome