BRIEF REPORTS Pediatric Dermatology Vol. 32 No. 5 e208–e209, 2015
Desmoplastic Trichoepithelioma: An Infrequent Entity not to be Missed: Report of Two Cases
Dermoscopy showed arborizing telangiectasias (Fig. 1C). Basal cell carcinoma (BCC) was suspected, and the entire lesion was excised. Pathology demonstrated proliferating basaloid cell rows within a desmoplastic stroma and keratin plugs among them (Fig. 1B), ﬁndings consistent with the diagnosis of DT. Patient 2
Abstract: Desmoplastic trichoepitheliomas are rare benign tumors with follicular differentiation. They have rarely been described in children. We report two children with this uncommon condition.
Desmoplastic trichoepithelioma (DT) is an uncommon benign tumor rarely seen in childhood. It presents as white, pinkish, or yellow papules or plaques with a central depressed area, most frequently located on the face. It is diﬃcult to diagnose on clinical grounds. We report two children with this unusual condition.
CASE REPORTS Patient 1 A healthy 13-year-old girl was seen for consultation for a slowly growing asymptomatic tumor on her right cheek. On physical examination, a whitish crateriform 7-mm papule was seen on her right cheek (Fig. 1A).
A healthy 11-year-old boy presented with an asymptomatic lesion on his right cheek that had been slowly growing for 7 years. Physical examination found a 6-mm whitish-to-yellowish papule with rounded borders and a depressed center on his right cheek (Fig. 2A). The lesion was excised. Pathology showed dermal strands of basaloid cells and some keratinous cysts with a desmoplastic stroma (Fig. 2B), conﬁrming the diagnosis of DT. DISCUSSION DTs are benign tumors with features of follicular diﬀerentiation and are rarely found in children. They have an incidence of 2 in 10,000 people, most of them being adult women (1). We found only four cases of DTs presenting in children published in the literature (1–4), including one girl with a congenital widespread milia-like eruption (1), one man with multiple DTs on his face since 5 years of age (4), and two 12-year-old boys with solitary tumors on the cheek (2,3). Although DTs are usually sporadic, three familial cases have been reported (5–7). The lesions were
Figure 1. (A) A 13-year-old girl with an ill-defined, round, 7-mm whitish papule with depressed center on her right cheek. (B) Dermis with a tumor of basaloid cells among thick collagen bundles and keratin plugs (hematoxylin and eosin, 409). (C) Dermoscopy: a whitish marbled background with vessels of different sizes, some mimicking telangiectasias.
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Brief Report e209
Figure 2. (A) An 11-year-old boy with a yellowish, round, crateriform, 6-mm papule on his right cheek. (B) Aggregations of monomorphic basaloid cells in the upper dermis with fibrous stroma in a cribriform pattern. There are also two keratin plugs.
clinically misdiagnosed in most cases. Misdiagnosis included squamous cell carcinoma (SCC) (2,3), sebaceous hyperplasia (5), and BCC (8), as in our ﬁrst case. Pathology is the gold standard for diagnosis. The clinical diﬀerential diagnosis also includes cutaneous leishmaniasis and other adnexal tumors. Histology demonstrates lines of basaloid cells distributed among thick collagen bundles with keratin plugs frequently intermingled among the tumor cells (8). The histopathologic diﬀerential diagnosis also includes BCC, SCC, and microcystic adnexal carcinoma. Shave biopsies can make it diﬃcult to distinguish DTs from malignant tumors such as well-diﬀerentiated SCCs (2,3) because desmoplastic trichoepithelomas can produce a reactive pseudoepitheliomatous (pseudocarcinomatous) process. In diﬃcult cases, immunohistochemistry markers such as cytokeratins 20, 10, 15, and d2-40, usually positive in DT, may conﬁrm the diagnosis (8). Dermoscopy showing telangiectasias on a whitish background as “marbled” without leaf-like structures or ovoid nests may also be helpful (9). Because DTs are benign, slow-growing tumors, management should be conservative. One child with spontaneous improvement has been reported (10). Curettage or abrasion techniques are good treatment options, but in case of diagnostic doubt, complete excision is recommended (2,3). REFERENCES 1. Carter JJ, Kaur MR, Hargitai B et al. Congenital desmoplastic trichoepithelioma. Clin Exp Dermatol 2007;32:522–524. 2. Rossi AM, Busam KJ, Mehrara B et al. Desmoplastic trichoepithelioma with overlying pseudoepitheliomatous hyperplasia mimicking squamous cell carcinoma in a pediatric patient. Dermatol Surg 2014;40:477–479.
3. Pignatti M, Iwuagwu FC, Harrison AP et al. Desmoplastic trichoepithelioma confused with cutaneous squamous cell carcinoma in childhood. J Plast Reconstr Aesthet Surg 2011;64:e92–e94. 4. Lazorick FC, Wood MG. Multiple desmoplastic trichoepitheliomas. Arch Dermatol 1982;118:361–362. 5. Wang SH, Tsai RY, Chi CC. Familial desmoplastic trichoepithelioma. Int J Dermatol 2006;45:756–758. 6. Dervan PA, O’Hegarty M, O’Loughlin S et al. Solitary familial desmoplastic trichoepithelioma. A study by conventional and electron microscopy. Am J Dermatopathol 1985;7:277–282. 7. Shapiro PE, Kopf AW. Familial multiple desmoplastic trichoepitheliomas. Arch Dermatol 1991;127:83–87. 8. Tebcherani AJ, de Andrade HF Jr, Sotto MN. Diagnostic utility of immunohistochemistry in distinguishing trichoepithelioma and basal cell carcinoma: evaluation using tissue microarray samples. Mod Pathol 2012;25:1345–1353. 9. Ardigo M, Zieﬀ J, Scope A et al. Dermoscopic and reﬂectance confocal microscope ﬁndings of trichoepithelioma. Dermatology 2007;215:354–358. 10. Chuo CB, Slator R, Brown RM et al. Management of desmoplastic trichoepithelioma in an infant. J Plast Reconstr Aesthet Surg 2008;61:1241–1244. Almudena Nuno-Gonzalez, M.D.* Isabel Colmenero, M.D.† Inmaculada de Prada, M.D.‡ Lucero Noguera-Morel, M.D.§ Antonio Martorell-Calatayud, M.D.¶ Angela Hernandez-Martin, M.D.§ Antonio Torrelo, M.D.§ *Department of Dermatology, Hospital Rey Juan Carlos, Mostoles, Madrid, Spain, †Department of Pathology, Birmingham Children’s Hospital, National Health Service Foundation Trust, Birmingham, UK, Departments of ‡Pathology and §Dermatology, Hospital Ni~ no Jesus, Madrid, Spain, ¶Department of Dermatology, Hospital de Manises, Valencia, Spain Address correspondence to Angela Hernandez-Martin, M.D., Department of Dermatology, Hospital Infantil Ni~ no Jesus, Avenida Menendez Pelayo, 65, 28009 Madrid. Spain, or e-mail: [email protected]