Dermatology: Practical and Conceptual Research Letter | Dermatol Pract Concept. 2024;14(3):e2024180 1 Cutaneous Signs of Breast Cancer: When a Dermatologic Evaluation is Useful After a Negative Mammography Nello Tommasino1, Federica Feo1, Mariateresa Cantelli1, Davide Fattore1 1 Section of Dermatology, Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy Key words: breast, cancer, skin, biopsy Citation: Tommasino N, Feo F, Cantelli M, Fattore D. Cutaneous Signs of Breast Cancer: When a Dermatologic Evaluation is Useful After a Negative Mammography. Dermatol Pract Concept. 2024;14(3):e2024180. DOI: https://doi.org/10.5826/dpc.1403a180 Accepted: April 4, 2024; Published: July 2024 Copyright: ©2024 Tommasino et al. This is an open-access article distributed under the terms of the Creative Commons Attribution- NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited. Funding: None. Competing Interests: None. Authorship: All authors have contributed significantly to this publication. Corresponding Author: Nello Tommasino, Section of Dermatology - Department of Clinical Medicine and Surgery, University of Naples Federico II, Via Pansini 5, 80131 Napoli, Italy. Tel: +39 - 081 – 7462457 Fax: +39 - 081 – 7462442 Email: nello.tommasino@libero.it Introduction Breast cancer is the most common cancer among women and is the second most frequent cancer worldwide [1]. Approximately 6%-10% of patients have Breast Cutaneous Cancer Manifestations (BCCM) as the first sign of cancer [2], but BCCMs usually occur in 23.9% of patients after the diagnosis [3]. BCCMs can be either represented by skin metastases and direct tumor extension, or as a paraneo- plastic syndrome [4]. Skin involvement has 2 main clinical presentations: inflammatory breast cancer (IBC) and breast cancer with non-inflammatory skin involvement (SI). IBC is characterized by painful, erythematous, and indurated breast skin manifestations (ie, peau d’orange) and is associated with a poor prognosis [5]. Classical non-inflammatory SI is char- acterized by ulceration, edema, or satellite skin nodules that occur directly from the breast adenocarcinoma [5]. Case Presentation We present the case of a 50-year-old patient who, following bi- lateral mastopexy, failed to achieve wound healing and devel- oped a large erythematous and crusted plaque with retraction of the areola-nipple complex (Figure 1). Breast tomosynthe- sis with contrast and 3D study with tomosynthesis revealed no malignant features. Since the manifestations had persisted for 2 years, she was referred to our clinic, where a skin biopsy was performed on suspicion of carcinomatous mastitis. The histological report showed morphological and immunohis- tochemical findings compatible with triple- negative high- grade (G3) breast cancer. A total-body positron-emission tomography-computed tomography (PET-CT) scan was performed and showed hypercapturing lymph nodes in the right axillary region. She was then referred to the Oncology Team and started therapy with 12 paclitaxel 2 Research Letter | Dermatol Pract Concept. 2024;14(3):e2024180 and carboplatin chemotherapy cycles, then she continued with epirubicin/cyclophosphamide and pembrolizumab. As a result, she showed a clear clinical improvement, testified by ulceration healing (Figure 2). Conclusions Skin involvement is an uncommon presentation of breast cancer [2]. Asymptomatic nodules and erythematous plaques are the most common clinical presentations, al- though manifestations may have different aspects such as erysipeloid carcinoma, carcinoma en cuirasse, zosteriform metastasis, melanoma-like metastasis, Paget-like metasta- sis [3]. In other cases, BCCMs may have the appearance of benign lesions including dermatitis, cellulitis, urticaria, and papulovesicular eruptions. This may be responsible for delay in diagnosis and treatment of carcinoma [5]. The presence of the signs described must raise a suspicion of malignancy, thus it is necessary to perform mammography or breast tomosynthesis [6], followed by biopsy of the affected site. Interestingly, in our case the radiological examination was not determinant, so the patient came to the attention of the dermatologists and a skin biopsy of the affected area was performed and confirmed the diagnosis of breast carcinoma with the status of neoplastic cell receptors, fundamental in prognostic terms. The case described shows how normal mammographic findings cannot rule out a breast carcinoma in presence of clinical skin signs that raise this suspicion. The aim of this report is to emphasize the role of the dermatologist in the early diagnosis of breast carcinoma, since, in a minority of cases, skin manifestations may be the first sign of presenta- tion of this malignancy. In addition, it should be highlighted that there is a need for more studies on the epidemiological and clinical features of BCCMs. References 1. Peach A, Blaise B, Parker J, Larson R. Noninflammatory pre- sentation of cutaneous breast cancer: a retrospective case series at a single academic institution with review of the literature. Dermatol Online J. 2022;28(4). DOI: 10.5070/D328458515. PMID: 36259855. 2. Milam EC, Rangel LK, Pomeranz MK. Dermatologic sequelae of breast cancer: From disease, surgery, and radiation. Int J Dermatol. 2021 Apr;60(4):394-406. doi: 10.1111/ijd.15303. Epub 2020 Nov 23. PMID: 33226140. 3. De Giorgi V, Grazzini M, Alfaioli B, et al. Cutaneous manifesta- tions of breast carcinoma. Dermatol Ther. 2010;23(6):581-589. DOI: 10.1111/j.1529-8019.2010.01365.x. PMID: 21054704. 4. Tan AR. Cutaneous manifestations of breast cancer. Semin Oncol. 2016 Jun;43(3):331-4. doi: 10.1053/j.seminoncol.2016.02.030. Epub 2016 Feb 23. PMID: 27178684. 5. Johnson C, Friedmann DP, Gade A, et al. Cutaneous Manifestation as Initial Presentation of Metastatic Breast Cancer: A Systematic Review. Cutis. 2021 Mar;107(3):E29-E36. doi: 10.12788/cutis.0223. PMID: 33956620. 6. Chippa V, Barazi H. Inflammatory Breast Cancer. In: StatPearls. Treasure Island (FL): StatPearls Publishing; April 16, 2023. Figure 1. First visit of the patient. A large erythematous and crusted plaque, with serous fissures and purulent exudate of the areolar re- gion and a retraction of the areola-nipple complex. Figure 2. Patient examination following cancer therapy. The diag- nosis of breast cancer reached by skin biopsy by the dermatologist made it possible to start anti-cancer therapy. The effectiveness of the latter is testified by the healing of the ulceration.