Dermatology: Practical and Conceptual Research Letter | Dermatol Pract Concept. 2023;13(2):e2023071 1 Acquired Bilateral Nevoid Telangiectasia Induced by Tamoxifen Irene Navarro-Navarro1, Alejandro Ortiz-Prieto1, Gonzalo Gallo-Pineda1, Myriam Viedma-Martínez1, David Jiménez-Gallo1, Mario Linares-Barrios1 1 Unidad de Gestión Clínica de Dermatología Médico-Quirúrgica y Venereología, Hospital Universitario Puerta del Mar, Cádiz, España Key words: bilateral nevoid telangiectasia, tamoxifen Citation: Navarro-Navarro I, Ortiz-Prieto A, Gallo-Pineda G, Viedma-Martínez M, Jiménez-Gallo D, Linares-Barrios M. Acquired Bilateral Nevoid Telangiectasia Induced by Tamoxifen. Dermatol Pract Concept. 2023;13(2):e2023071. DOI: https://doi.org/10.5826/dpc.1302a71 Accepted: July 5, 2023; Published: April 2023 Copyright: ©2023 Navarro-Navarro 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: Irene Navarro Navarro, MD, Hospital Universitario Puerta del Mar. Unidad de Gestión Clínica de Dermatología, 2ª planta. Avenida Ana de Viya 21, 11009, Cádiz, Spain Phone: +34629924839 E-mail: irenen.navarro@gmail.com Introduction Unilateral nevoid telangiectasia (UNT) is a superficial tel- angiectasia of the upper body characterized by showing a unilateral dermatomal distribution, typically affecting der- matomes from C3 to T3 [1]. Although the exact cause is un- known, the association with hyperestrogenic states has been described [2]. Bilateral nevoid telangiectasia (BNT) is a rare variant of UNT affecting both sides of the body. We present a case of BNT in relation with tamoxifen treatment. Case Presentation A 41-year-old female attended our dermatology department due to the appearance of asymptomatic cutaneous lesions on the upper trunk and arms. She had a history of ductal cancer of the right breast stage IA with positivity for estrogen and progesterone receptors, treated with surgery, radiotherapy and tamoxifen. She did not have any other drug history. The cutaneous lesions had appeared several weeks after finishing radiotherapy and starting tamoxifen treatment. Physical ex- amination showed symmetric purpuric linear macules on the inner arms, chest and upper back (Figure 1). The macules had a dermatomal distribution following the T1 dermatome (Figure 2). She was interrogated for extracutaneous mani- festations such as digestive bleeding or epistaxis, without reporting any systemic symptoms. A skin biopsy showed dilated blood vessels in the upper dermis with mild perivas- cular inflammation and normal number of mastocyte cells. Immunohistochemistry showed positivity to estrogen recep- tors in fibroblastic cells. Blood tests including biochemistry, blood count, coagulation study, estrogen and progesterone levels and viral hepatitis serology were normal or negative. Stool blood test was negative. She was diagnosed with BNT secondary to tamoxifen. Conclusions BNT, although bilateral in its presentation, is analogous to UNT in that it follows the characteristic dermatomal 2 Research Letter | Dermatol Pract Concept. 2023;13(2):e2023071 distribution of the telangiectasias. However, this variant seems to be less frequent. Over a hundred cases of UNT have been described in the literature, and only twenty-four cases of BNT [3]. Although both entities are similar in their presentation, some epidemiological differences have been described between the two variants. BNT is more frequent in male patients whereas UNT occurs predominantly in women. Patients with BNT are usually older than those with UNT, with a later onset of presentation, and higher associa- tion with underlying diseases such as liver diseases, diabetes and smoking [4]. The association of UNT with hyperestrogenic states has been proposed, owing to the high prevalence in patients during puberty and pregnancy [5]. Tamoxifen is a selective estrogen receptor modulator used in breast cancer with pos- itivity for hormonal receptors. This therapy has an antag- onist effect on breast tissue, but an agonist effect on bone, liver, skin and endometrium. Association between UNT and other drugs, such as chemotherapy agents, has also been proposed [6]. We hypothesize that tamoxifen led to an increase of estro- gen receptors on the dermatomal skin of our patient, which may have been the cause for the presentation of BNT in this case. This is the first case reported, to our knowledge, of nev- oid telangiectasia (UNT or BNT) in relation with tamoxifen. This contributes to the hypothesis that hyperestrogenic states may be important not only for the pathogenesis of UNT but also for BNT. However, more studies directed to explain the underlying mechanisms causing UNT and BNT are needed to validate our observations. References 1. Duong MH, Raymond CP. Unilateral dermatomal superficial tel- angiectasia. Can Med Assoc J. 1983;129(10):1117-1118. PMID: 6627172.PMCID: PMC1875470. 2. Uhlin SR, McCarty KS Jr. Unilateral nevoid telangiectatic syndrome. The role of estrogen and progesterone receptors. Arch Dermatol. 1983;119(3):226-228. DOI: 10.1001/arch- derm.119.3.226. PMID: 6824361. 3. Jee H, Kim TG, Kim DS, Kim DY, Lee MG. Acquired bilateral nevoid telangiectasia: Report of 9 cases. Eur J Dermatology. 2013;23(5):736-737. DOI: 10.1684/ejd.2013.2141. PMID: 24211825. 4. Kim EJ, Park HS, Yoon HS, Kim KH, Cho S. Demographic and clinical differences between unilateral and bilateral forms of naevoid telangiectasia: A retrospective study with review of the literature. Br J Dermatol. 2015;172(6):1651-1653. DOI: 10.1111/bjd.13615. PMID: 25495722. 5. Sánchez Conejo-Mir J, Ortega Resina M CMF. Unilateral nev- oid telangiectasia syndrome. Study of cutaneous estrogen recep- tors. Med Cutan Ibero Lat Am. 1984;12(6):469-475. PMID: 6397668. 6. Rodríguez-Martín M, Sáez M, Carnerero A, et al. Unilat- eral naevoid telangiectasia in a young man after chemother- apy: a simple coincidence or a new clinical association? J Eur Acad Dermatology Venereol. 2006;20(8):1001-1002. DOI: 10.1111/j.1468-3083.2006.01593.x. PMID: 16922953. Figure 1. Clinical image of bilateral nevoid telangiectasia. Symmet- ric purpuric linear macules on the arms and chest following the T1 dermatome. Figure 2. Clinical image of bilateral nevoid telangiectasia. Linear purpuric – brownish macules following the T1 dermatome.