Indian Journal of Dermatology
: 2013  |  Volume : 58  |  Issue : 5  |  Page : 409-

Multiple familial trichoepithelioma with malignant transformation

Rehab M Samaka1, Ola A Bakry2, Iman Seleit2, Moshira M Abdelwahed1, Rania A Hassan1,  
1 Department of Pathology, Andrology and S.T.Ds, Faculty of Medicine, Menoufiya University, Shebin Elkom, Egypt
2 Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine, Menoufiya University, Shebin Elkom, Egypt

Correspondence Address:
Ola A Bakry
Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine, Menoufiya University, Shebin Elkom


Trichoepithelioma (TE) is a benign tumor of follicular origin that presents as small, skin-colored papules predominantly on the face. When more than one family member is affected, the disease is known as multiple familial trichoepithelioma (MFT). It is a rare autosomal dominant (AD) skin disease. Malignant transformation is very rare. We present a case of MFT in a female patient and her father with malignant transformation to basal cell carcinoma (BCC) in the father. We summarized the main histological differential parameters between TE and BCC and applied immunophenotyping for both by administration of Bcl2, CD34, CD10 and androgen receptor (AR) antibodies.

How to cite this article:
Samaka RM, Bakry OA, Seleit I, Abdelwahed MM, Hassan RA. Multiple familial trichoepithelioma with malignant transformation.Indian J Dermatol 2013;58:409-409

How to cite this URL:
Samaka RM, Bakry OA, Seleit I, Abdelwahed MM, Hassan RA. Multiple familial trichoepithelioma with malignant transformation. Indian J Dermatol [serial online] 2013 [cited 2023 Sep 26 ];58:409-409
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Full Text


Trichoepithelioma (TE) is a benign adnexal neoplasm. Lesions are rounded, skin-colored, firm papules or nodules, 2-8 mm in diameter. They are located mainly on nasolabial folds, nose, forehead, upper lip, and scalp. [1],[2]

Multiple familial trichoepithelioma (MFT) is an autosomal dominant (AD) disorder beginning in childhood and progresses slowly. Malignant transformation of such lesions is quite rare. [3]

 Case History

Case 1

A 38-year-old female presented with a 27 years history of asymptomatic, skin colored papules. Lesions were firm in consistency, ranging from 5 to 10 mms in diameter and were distributed on her face; around eyes, on the nose, nasolabial folds and upper lip [Figure 1]a and b. General examination revealed no abnormality. Dermatological examination revealed normal skin and mucous membranes. Patient's father had similar lesions but there was no affection of other family members. Routine investigations including hemogram, urine analysis, liver and renal function tests were non contributary.{Figure 1}

Excisional biopsy of a representative lesion was done after taking patient consent. Histopathological examination of hematoxylin and eosin (H and E)-stained sections revealed superficial dermal, well circumscribed, non capsulated, symmetrical lesion. This lesion was formed of solid aggregates of uniform basaloid cells with peripheral palisading but lacked epidermal connection, pilar differentiation and retraction artifacts. They were surrounded by a stroma with increased number of fibroblasts [Figure 2]a. Cells were uniform, with large nuclei and scanty cytoplasm and lacked cytological atypia, mitoses or necrosis [Figure 2]b. Aggregations of fibroblasts, representing abortive attempts to form papillary mesenchyme (papillary mesenchymal bodies), were detected, that are characteristic of TE [Figure 2]c. Small foreign body granuloma was detected [Figure 2]d.{Figure 2}

Based on clinical and histopathological criteria, the diagnosis of immature TE was reached. However the presence of solid basaloid aggregates with peripheral palisading may lead to a misdiagnosis of BCC. Thus, we performed immunohistochemical (IHC) staining for Bcl2, CD10, CD34 and androgen receptor (AR) antibodies. The outermost epithelial cells showed positivity for Bcl2 [Figure 3]a. Both CD10 and CD34 stained the stromal cells but not the basaloid cells [Figure 3]b and c. Both tumor cells and stroma did not show any AR immunoreactivity [Figure 3]d. The final diagnosis was TE. The patient was treated by CO2 laser with no recurrence for one year.{Figure 3}

Case 2

A 65-year-old male, the father of the first patient, was presented similarly by papulo-nodular lesions with the same distribution and morphology described in his daughter but larger in size [Figure 4]a. These lesions appeared since 57 years but were neglected as they were asymptomatic. One month before reaching us, one of those nodules enlarged markedly to reach a size of 6 cm with repeated bleeding, ulceration and crustation [Figure 4]b.{Figure 4}

Excisional biopsy was taken from a representative papule and incisional biopsy was taken from the enlarging nodule after taking patient consent.

For the former biopsy, examination of H and E-stained sections and immunohistochemical-stained sections of the same antibodies revealed the same results as the first case.

For the latter biopsy, islands of basaloid cells extending from the epidermis to the dermis with peripheral palisading and prominent stromal epithelial retraction artifacts were observed. Cells were large, with uniform large nuclei and scanty cytoplasm. So the diagnosis of BCC was suggested. Immunohistochemical staining revealed that, the basaloid cells stained diffusely with Bcl2 [Figure 5]a, CD10 [Figure 5]b and focally with AR antibodies [Figure 5]c. CD34 immunostaining was negative [Figure 5]d.{Figure 5}


TE is a benign neoplasm of follicular germinative cells. [1] Clinically, this tumor occurs either as a solitary lesion without any familial association or as multiple lesions in MFT. [3] Lesions develop as firm, non-ulcerated, flesh-colored papules with a propensity for the face and rarely exceed 0.5 cm in size. [2]

MFT was initially described in 1892 under the names "multiple benign cystic epithelioma" and "epithelioma adenoides cysticum". [3]

In most cases, lesions appear in childhood and gradually increase in number and size. Ulceration may occur rarely. [1] The gene associated with the familial type of TE links to the short arm of chromosome 9. It encodes tumor suppressor genes and if altered, cellular proliferation may be upregulated. [4] However, other reports documented defects of a tumor repressor gene on chromosome 16, CYLD. [5] To date, 17 mutations of this gene have been described to be associated with MFT. [6] Males and females receive the gene equally, but because of lessened expressivity and penetrance in men, most patients are women. [4]

Biopsy is diagnostic. TE contains adenoid network or solid aggregates of basaloid cells, horn cysts, and abortive hair papillae. Horn cysts are the most characteristic tumor component. [1] However, some lesions show relatively little differentiation towards hair structures with very few or even absent horn cysts. [3] These lesions considered as immature TE as in our cases.

The histopathological findings found in our cases were summarized in [Table 1].{Table 1}

TE is a benign lesion that may be excised by a small margin of healthy tissue, thereby facilitating surgical repair; however, BCC is a locally malignant tumor treated by excision of the lesion with 3-4 mm margins. So the differentiation between both is mandatory. Diagnosis may be assisted in a given case by clinical data, and the presence of hereditary transmission. [7] The distinction between BCC and immature TE on histopathologic basis is quite difficult especially in small superficially shaved specimens. This is due to the subtle morphologic differences between the two entities. Immunohistochemistry has been considered for the differential diagnosis between both tumors. Bcl-2 expression has been found to be limited to the outermost basaloid cells in tumor nests of TE and to be diffuse in BCC. CD10 gives positive stromal staining in TE and epithelial staining in BCC. [8] CD34 is considered to be a good candidate because the stroma is positive in TE and negative in BCC. [9]

More recent studies have shown AR expression in a number of mature epithelial structures and epithelial neoplasms including BCC. In contrast, AR expression was absent in mature hair follicles or the few trichogenic neoplasms studied to date. These findings suggested that AR expression might be a useful adjunct in the histologic differential diagnosis between BCC and TE. [10]

The immunhistochemical staining of the used antibodies were summarized in [Table 2]. Our results were in accordance with others. [8],[9],[10]{Table 2}

Malignant transformation of TE to BCC is rare. [7] Literature review showed that only 12 cases were reported up till now with the first case in 1959. [11] Malignant transformation denotes loss of heterozygosity in CLYD gene in the 9p21 and 9q22 chromosomal regions. [7] Matt et al., [12] had indicated that there is a common gatekeeper between TE and BCC. Tan and his associates [13] concluded that BCC arising on top of MFT lesions may represent a novel contagious gene syndrome.

Multiple treatment modalities had been suggested for TE, including surgical excision and grafting, chemical peeling and CO2 laser. [1],[2],[6] The first case had been treated by Co2 laser. Regarding the treatment of BCC in the second case, it had been surgically excised but he was not interested in treating TE lesions.


1Saha A, Das NK, Gharami RC, Chowdhury SN, Datta PK. A clinico-histopathological study of appendageal skin tumors, affecting head and neck region in patients attending the dermatology opd of a tertiary care centre in eastern India. Indian J Dermatol 2011;56:33-6.
2Singh PK, Panday SS, Singh G. Trichoepithelioma. Indian J Dermatol 1986;31:13-5.
3Yiltok SJ, Echejoh GO, Mohammad AM, Ituen AM, Igoche MI, Dades OT. Multiple familial trichoepithelioma: A case report and review of literature. Niger J Clin Pract 2010;13:230-2.
4Harada H, Hashimoto K, Ko MS. The gene for multiple familial trichoepithelioma maps to chromosome 9p21. J Invest Dermatol 1996;107:41-3.
5Zhang XJ, Liang YH, He PP, Yang S, Wang HY, Chen JJ, et al. Identification of the cylindromatosis tumor-suppressor gene responsible for multiple familial trichoepithelioma. J Invest Dermatol 2004;122:658-4.
6Wang FX, Yang LJ, Li M, Zhang SL, Zhu XH. A novel missense mutation of CYLD gene in a Chinese family with multiple familial trichoepithelioma. Arch Dermatol Res 2010;302:67-70.
7Pariser RJ. Multiple hereditary trichoepithelioma and basal cell carcinoma. J Cutan Pathol 1986;13:111-7.
8Cordoba A, Guerrero D, Larrinaga B, Iglesias ME, Arrechea MA, Yanguas JI. Bcl-2 and CD10 expression in the differential diagnosis of trichoblastoma, basal cell carcinoma, and basal cell carcinoma with follicular differentiation. Int J Dermatol 2009;48:713-7.
9Kirchmann TT, Prieto VG, Smoller BR. CD34 staining pattern distinguishes basal cell carcinoma from trichoepithelioma. Arch Dermatol 1994;130:589-92.
10Izikson L, Bhan A, Zembowicz A. Androgen receptor expression helps to differentiate basal cell carcinoma from benign trichoblastic tumors. Am J Dermatopathol 2005;27:91-5.
11Snekszer M. Simultaneous occurrence of familial cystic adenoidal epithelioma (trichoepithelioma) and basalioma. Borgyogy Venerol Sz 1959;35:282-5.
12Matt D, Xin H, Vortmeyer AO, Burg G, Böni R. Sporadic trichoepithelioma demonstrates deletions at 9q22.3. Arch Dermatol 2000;136:657-60.
13Tan J, Levitt J, Phelps R. Multiple trichoepitheliomas and basal cell carcinoma: A novel syndrome? J Cutan Pathol 2005;32:71-123. Abstracts of the Papers Presented at the 41 st Annual Meeting of the American Society of Dermatopathology.