Pilomatricoma: A View into Its Rare Dermoscopic Insight
Year: 2026
Type: article
Study design: Case Report
Abstract: Dear Sir, Pilomatricoma or pilomatrixoma or calcifying epithelioma of Malherbe is a benign tumor arising from the immature hair matrix cells, having an adnexal dermal or dermo-subcutaneous origin.[1] It accounts for almost 1% of all benign skin lesions.[2] Hereby, we report a case of a 45-year-old male diagnosed with pilomatricoma, based on clinical-histological and dermoscopic findings. A 45-year-old male presented to us with a solitary, gradually progressive, skin-colored lesion over the left side of his upper lip for 6 months. There was no history of pain, bleeding on manipulation, or similar complaints in family members. Cutaneous examination revealed a solitary, well-circumscribed, 1.5 cm × 2 cm, nontender, firm, erythematous nodule with peripheral ulceration over the left side of the upper lip, approximately 2.5 cm from the philtrum [Figure 1a]. The rest of the cutaneous and systemic examination was normal. Dermoscopy was performed using a handheld 3Gen DermLite DL4 dermoscope at ×10 magnification, with One Plus 5 smartphone with a 48-megapixel camera, which revealed white shiny areas; red, homogeneous areas; blue–gray zones; and ulceration [Figure 1b]. Nodular basal cell carcinoma, pyogenic granuloma, amelanotic melanoma, clear cell acanthoma, and pilomatricoma were considered differential diagnoses. Histopathology revealed a normal epidermis with a large nodule composed of trabeculae made up of two types of cells: basophilic cells of the hair matrix and pale eosinophilic shadow cells, surrounded by lymphohistiocytic infiltrates and multiple giant cells forming granulomas in the reticular dermis [Figure 2a and b]. Considering the clinical, dermoscopic, and histopathologic features, a final diagnosis of pilomatricoma was reached. Surgical excision of the lesion was done.Figure 1: A solitary, firm, erythematous nodule with ulceration over the upper lip (a). In dermoscopic view (×10, polarized mode) white shiny area (black star), a red homogenous area (blue arrow), blue–gray area (red star), and ulceration (black circle) at the periphery (b)Figure 2: (a and b) Histopathology revealed a large nodule having trabeculae composed of two types of cells, as basophilic cells of hair matrix and pale eosinophilic shadow cells with surrounding lymphocytic infiltrate (H and E, a: ×10, b: ×40)Pilomatricoma was first described by Malherbe and Chenantais in 1880 and given the name of calcifying epithelioma of sebaceous glands. It was later renamed as Pilomatrixoma by Forbis and Helwig in 1961 to denote its origin from the hair matrix cells.[3] The etiology remains uncertain, but evidence suggests that mutations in the CTNNB1 gene are responsible.[3] Pilomatrixomas have a slight female preponderance and are present generally in the first two decades of life, with a smaller incidence in the sixth decade.[3] It is generally solitary, but multiple pilomatrixomas, especially more than six, denote a syndromic association.[1] Atypical variants have been described, including bullous, anetodermic, perforating, and keloidal, but they are rare.[1] It can be easily misdiagnosed with other entities like an epidermal cyst, dermoid cyst, adenopathy, lipoma, hemangioma, malignant melanoma, basal cell carcinoma, squamous cell carcinoma, and dermatofibroma. Dermoscopy is a noninvasive, bedside tool that helps us assess epidermal and dermal structures and exclude other common differentials, thereby facilitating the diagnosis of pilomatricoma. The first dermoscopic findings for pilomatrixoma were given by Zaballos as the presence of multiple irregular whitish structures and streaks on dermoscopy in 90% of cases.[3] Tricolor (blue–yellow–reddish nodular) appearance on dermoscopy can be considered a clue to diagnose pilomatricoma.[1,3] A few authors reported that a bicolor nodular aspect can be seen in typical pilomatricoma.[4,5] The classical dermoscopic pattern includes irregular white areas, yellowish–whitish structureless areas, white streaks, vascular areas, red homogenous zones, and blue–gray zones, as seen in our case, in addition to ulceration.[1,3–5] Irregular white or yellow structures and streaks correspond histologically to large masses of eosinophilic cornified material located in well-developed lobules and also to calcification or granulomas. The reddish area may be attributed to the presence of proliferating vessels in the papillary dermis and hemorrhage.[3] Grayish blue areas are correlated with melanin pigment within aggregates of basaloid cells. Other findings in atypical pilomatricomas that have been described are yellowish lobules over an erythematous background surrounded by crown vessels, scar-like appearance, hairpin vessels, linear-irregular vessels, dotted vessels, and ulceration or transepidermal elimination.[1,3] Management includes surgical excision or curettage. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Source: Clinical Dermatology Review
Institution: Government Medical College
Language: English
Topic: Cancer and Skin Lesions
Subfield: Dermatology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7119478134