Unexpected case of non-syndromic neighbouring basal cell carcinomas

• Published in: BMJ case reports Vol. 13; no. 12; p. e240037
• Main Authors: Plachouri, Kerasia-Maria, Mulita, Francesk, Georgiou, Sophia, Spiliopoulos, Theofanis
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 09.12.2020; BMJ Publishing Group LTD; BMJ Publishing Group
• Subjects: Aged; Biopsy; Carcinoma, Basal Cell - diagnosis; Carcinoma, Basal Cell - pathology; Case reports; Cloning; dermatology; Family medical history; Female; Humans; Images In; Lumbosacral Region; Neoplasms, Multiple Primary - diagnosis; Neoplasms, Multiple Primary - pathology; Pathogenesis; Skin cancer; Skin Neoplasms - diagnosis; Skin Neoplasms - pathology; Tumors; skin cancer; dermatology
• ISSN: 1757-790X; 1757-790X
• DOI: 10.1136/bcr-2020-240037

Correspondence to Francesk Mulita; oknarfmulita@hotmail.com Description A 66-year-old Caucasian woman (Fitzpatrick skin type III) presented in our department for the evaluation of a lesion in the lumbosacral area, that had first appeared approximately 3 years prior to the referral and was gradually progressing in size. BCC is the most common skin neoplasm, with multiple causes such as ultraviolet (UV) radiation exposure, genetic predisposition with Fitzpatrick skin types I and II, or hereditary conditions, such as Xeroderma pigmentosum and Gorlin-Goltz syndrome.1 For the cases where numerous BCCs occur without the evident influence of an extrinsic risk factor, the term multiple non-syndromic BCCs is used.2 The reporting of such patients in the literature is very limited, and the BCCs in the described cases tend to have similar morphological characteristics.2 Dysregulated Hedgehog signalling is a hallmark of BCC pathogenesis.3 The cellular origin of these tumours is believed to arise from the basal cells of the interfollicular epidermis and infundibulum of hair follicles.3 Although the exact pathogenesis of non-syndromic BCCs is not fully elucidated, an association with the biological events that lead to cutaneous field cancerisation can be speculated. The pathogenetic mechanism of field cancer is based on the following model: acquired genetic alterations in skin stem cells (mostly UV-induced) give origin to proliferating clones that expand in the epidermis and form patches of mutated cells.4 These clones and subclones acquire additional mutations that can result in carcinomatous transformation over time.4 The synchronous appearance of multiple neighbouring BCCs with distinct clinical and dermatoscopic characteristics on areas that are not sun-exposed and in otherwise healthy patients, without history of malignancy or other relevant comorbidities, such as immunosuppression or other pathogenic background, and without relevant family history, is rather uncommon.2 The peculiar coincidence in our case is the immediate proximity of the three BCCs, their unusual distribution in a linear pattern and the fact that they displayed different macroscopic and dermatoscopic features (figure 2).