The mammary ridge—A case report of multiple ectopic breast masses


      • Failure of the embryologic mammary ridge to atrophy will lead to the formation of glandular tissue anywhere along the milk line.
      • There is rare potential to develop a primary breast malignancy including ductal or lobular carcinomas, as well as benign growths such as pseudoagniomatous stromal hyperplasia (PASH) in ectopic breasts.
      • Radiologic appearance is nonspecific and full workup is required for diagnosis.
      • Elective resection may be considered.


      Ectopic or accessory breasts describe residual breast tissue that fails to regress during normal embryologic development anywhere outside the expected locations. Ectopic breast tissue is seen in 2–6% of the population and is categorized into two types: supernumerary and aberrant breast tissue . The extent of development of this accessory tissue varies from rudimentary to complete with organized glandular and ductal development. Given this, it is possible for the same pathology that affects normally positioned breast tissue to also affect accessory breast tissue.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Clinical Imaging
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


      1. Cyrlak, D., and P. M. Carpenter. “Breast Imaging Case of the Day. Pseudoangiomatous Stromal Hyperplasia.” Radiographics: A Review Publication of the Radiological Society of North America, Inc 19, no. 4 (August 1999): 1086–88. doi:10.1148/radiographics.19.4.g99jl201086.

        • DeFilippis Ersilia M.
        • Arleo Elizabeth Kagan
        The ABCs of Accessory Breast Tissue: Basic Information Every Radiologist Should Know.
        AJR Am J Roentgenol. May 2014; 202: 1157-1162
        • Goyal Shikha
        • Puri Tarun
        • Gupta Ruchika
        • Julka Pramod K.
        • Rath Goura K.
        Accessory breast tissue in axilla masquerading as breast cancer recurrence.
        J Cancer Res Ther. June 2008; 4: 95-96
        • Hughes E.S.
        The development of the mammary gland: Arris and gale lecture, delivered at the Royal College of Surgeons of England on 25th October, 1949.
        Ann R Coll Surg Engl. February 1950; 6: 99-119
        • Javed Asma
        • Lteif Aida
        Development of the human breast.
        Semin Plast Surg. February 2013; 27: 5-12
        • Lesavoy M.A.
        • Gomez-Garcia A.
        • Nejdl R.
        • Yospur G.
        • Syiau T.J.
        • Chang P.
        Axillary breast tissue: clinical presentation and surgical treatment.
        Ann Plast Surg. October 1995; 35: 356-360
        • Madej B.
        • Balak B.
        • Winkler I.
        • Burdan F.
        Cancer of the accessory breast-a case report.
        Adv Med Sci. 2009; 54: 308-310
        • Marinopoulos Spyridon
        • Arampatzis Ioannis
        • Zagouri Flora
        • Dimitrakakis Constantine
        Pseudomamma of the inguinal region in a female patient: a case report.
        Int J Surg Case Rep. 2015; 12: 71-74
        • Marshall M.B.
        • Moynihan J.J.
        • Frost A.
        • Evans S.R.
        Ectopic breast cancer: case report and literature review.
        Surg Oncol. October 1994; 3: 295-304
        • Powell C.M.
        • Cranor M.L.
        • Rosen P.P.
        Pseudoangiomatous Stromal Hyperplasia (PASH). A Mammary Stromal Tumor with Myofibroblastic Differentiation.
        Am J Surg Pathol. March 1995; 19: 270-277
        • Rho J.Y.
        • Juhng S.K.
        • Yoon K.J.
        Carcinoma originating from aberrant breast tissue of the right upper anterior Chest Wall: a case report.
        J Korean Med Sci. August 2001; 16: 519-521
        • Velanovich V.
        Ectopic breast tissue, supernumerary breasts, and supernumerary nipples.
        South Med J. September 1995; 88: 903-906
        • Wysokinska Ewa M.
        • Keeney Gary
        Breast cancer occurring in the Chest Wall: rare presentation of ectopic milk line breast cancer.
        J Clin Oncol Off J Am Soc Clin Oncol. April 1, 2014; 32: e35-e36
        • Caceres Manuel
        • Shih Jennifer
        • Eckert Michelle
        • Gardner Rhea
        Metaplastic carcinoma in an ectopic breast.
        South Med J. April 2002; 95: 462-466
        • van Herwaarden-Lindeboom M.Y.A.
        • van Hillegersberg R.
        • van Diest P.J.
        Ectopic lobular breast cancer on the anterior chest wall: a rare entity.
        J Clin Pathol. October 17, 2006; 60: 940-941