Microglandular adenosis (MGA) of the breast is a glandular proliferation of uncertain malignant potential, which mimics invasive carcinoma due to haphazard infiltrative growth in breast stroma and the lack of a myoepithelial cell layer. The term atypical microglandular adenosis (AMGA) is used when the glandular structures are more crowded, with a back-to-back architecture and higher variation in size and shape; epithelial proliferation, as well as nuclear atypia and mitotic activity, can be present.
MGA is an exceedingly rare breast lesion.
It affects patients with an age range between adolescence and senescence.
All reported patients with microglandular adenosis are female.
There is no predilection for a particular quadrant in the breast. MGA can be unifocal or multifocal (Clement and Azzopardi 1983).
MGA usually is asymptomatic and may present as a microscopic lesion or as a palpable mass (Rosen 1983). It can...
References and Further Reading
- Geyer, F. C., Kushner, Y. B., Lambros, M. B., Natrajan, R., Mackay, A., Tamber, N., … & Reis-Filho, J. S. (2009). Microglandular adenosis or microglandular adenoma? A molecular genetic analysis of a case associated with atypia and invasive carcinoma. Histopathology, 55, 732–743.Google Scholar
- Geyer, F. C., Lacroix-Triki, M., Colombo, P. E., Patani, N., Gauthier, A., Natrajan, R., … & Marchio, C. (2012). Molecular evidence in support of the neoplastic and precursor nature of microglandular adenosis. Histopathology, 60, E115–E130.Google Scholar
- Geyer, F. C., Berman, S. H., Marchiò, C., Burke, K. A., Guerini-Rocco, E., Piscuoglio, S., … & Schnitt, S. J. (2017). Genetic analysis of microglandular adenosis and acinic cell carcinomas of the breast provides evidence for the existence of a low-grade triple-negative breast neoplasia family. Modern Pathology, 30, 69.Google Scholar
- Guerini-Rocco, E., Piscuoglio, S., Ng, C. K., Geyer, F. C., De Filippo, M. R., Eberle, C. A., … & Yatabe, Y. (2016). Microglandular adenosis associated with triple-negative breast cancer is a neoplastic lesion of triple-negative phenotype harbouring TP53 somatic mutations. The Journal of Pathology, 238, 677–688.Google Scholar
- Khalifeh, I. M., Albarracin, C., Diaz, L. K., Symmans, F. W., Edgerton, M. E., Hwang, R. F., & Sneige, N. (2008). Clinical, histopathologic, and immunohistochemical features of microglandular adenosis and transition into in situ and invasive carcinoma. The American Journal of Surgical Pathology, 32, 544–552.PubMedCrossRefGoogle Scholar
- Lakhani, S. R., Ellis, I. O., Schnitt, S. J., Tan, P. H., & van de Vijver, M. J. (2012). WHO classification of tumors of the breast (pp. 106–107). World Health Organization. Lyon, France. ISBN-10: 9283224337.Google Scholar
- Salarieh, A., & Sneige, N. (2007). Breast carcinoma arising in microglandular adenosis: A review of the literature. Archives of Pathology & Laboratory Medicine, 131, 1397–1399.Google Scholar