 Corresponding author: ME Chiemeka Department of Anatomic Pathology and Forensic Medicine, Nnamdi Azikiwe University Teaching Hospital, Nnewi. Copyright © 2021 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0. Dermatofibrosarcoma protuberans of the breast: A case report of a rare breast tumour CD Emegoakor 1 , HC Nzeako 1 , MI Nwosu 1 , ME Chiemeka 2, * and FE Menkiti 2 1 Department of Surgery, Nnamdi Azikiwe University Teaching Hospital, Nnewi. 2 Department of Anatomic Pathology and Forensic Medicine, Nnamdi Azikiwe University Teaching Hospital, Nnewi. World Journal of Advanced Research and Reviews, 2021, 11(02), 112–116 Publication history: Received on 05 June 2021; revised on 27 July 2021; accepted on 29 July 2021 Article DOI: https://doi.org/10.30574/wjarr.2021.11.2.0317 Abstract Introduction: Dermatofibrosarcoma protuberans (DFSP) is an intermediate and slow-growing sarcoma, arising most commonly in the trunk and extremities and rarely in the breast. It may be recurrent, but metastasis is rare. Excision with good resection margins reduces the rate of recurrence. Case Presentation: A 28-year-old lady presented with a painless lump in the left breast of 16 years duration. Examination revealed an ulcerated firm mass, well defined, with perilesional nodules on the skin of the breast. Wedge biopsy favoured Borderline Phylloides Tumour over DFSP. Patient was offered mastectomy and the histology of the specimen confirmed Fibrosarcomatous DFSP. Conclusion: This stresses the importance of histology in diagnosing a rare breast tumour. This is very important because it may show similar appearance to other benign and malignant breast lesions, which makes clear the role of pathological investigation to make a definitive diagnosis. Keywords: Breast; Dermatofibrosarcoma Protuberans; Mesenchymal Tumour; Fibrosarcomatous DFSP 1. Introduction Dermatofibrosarcoma Protuberans (DFSP) is a rare tumour involving the deep dermis and subcutaneous tissues. It accounts for 1.0% of all soft tissue sarcomas, and for less than 0.1% of all malignant tumours [1]. The disease can occur at any age, but 20-50 years age group is most commonly affected. It is a slow-growing sarcomatous tumour involving the trunk and extremeties [2]. It was first described by Darier and Ferrand in 1924 [3]. The tumour has a variable degree of malignancy with a high tendency for local invasion and a high rate of recurrence, especially if a negative margin fails to be achieved in the primary resection surgery [4] [5]. Metastasis is rare. Early detection and treatment is possible because of its superficial location [1]. Imaging findings for DFSP is usually non-specific. While it is true that the trunk and extremeties are most commonly affected, DFSP can affect virtually all parts of the body. However, occurrence in female breast is extremely rare [6]. None has been reported in our environment occurring in female breast; and the only one reported was seen in a male breast [7]. Thus, the purpose of this article is to report a case of DFSP involving the left breast of a 28-year old lady, and to do literature review on the subject matter.