Folliculosebaceous cystic hamartoma of the right cheek and inner canthus

ARTICLE

Auteur(s) : Chun-li ZHOU^1,2, Jun Deng¹, Fei HAO¹, Xi-chuan YANG¹

¹Dermatology Department of Southwest Hospital, The Third Military Medical University, 400038 Chongqing, China
²Dermatology Department of Xinqiao Hospital, The Third Military Medical University, 400038 Chongqing, China

Folliculosebaceous cystic hamartoma (FSCH) is a rare cutaneous hamartoma composed of both ectodermal and mesodermal components. Lesions are mainly distributed on the central face and scalp. Here we present an unusual case of FSCH with its unique location on the right cheek and inner canthus.

A 34-year-old Chinese male complained about slow-growing, plaque-like, exophytic, multinodular lesions on his right cheek and inner canthus for 27 years. Removal was performed at the age of 16. Two years later, similar nodules re-appeared. He had no significant past medical history or family history. Examination found a dark red triangular scar on his right cheek, around which were six red or yellowish-red nodules, 8-30 mm in diameter. A skin-colored, dome-shaped nodule (10 mm in diameter) was found on his inner canthus. The lesions were firm with no tenderness. Sebaceous materials could be expressed from some of the nodules. None of them had central terminal hairs (figure 1A). No other skin lesions or abnormalities of internal organs were found. Histopathological examination showed numerous irregular cystic structures located in the dermis. Many mature sebaceous lobules were attached to distorted and dilated infundibular units were separated by clefted lamellar fibrous tissues (figure 1B). Foci of mature adipocytes were seen in the dense fibrous tissue adjacent to pilosebaceous structures (figure 1C). These features were characteristic of FSCH. The lesions on the right cheek were excised completely and reconstructed under local anesthesia. It has not recurred for 3 years.

Since the first five cases, described by Kimura et al. [1] in 1991, approximately 30 cases of FSCH have been reported in the English literature. FSCH were found in all age groups. Females were affected more often than males. The lesions primarily occur on the central face and scalp of young adults (> 90%). Lesions on genitals, aures, nipple, extremities, as well as croup are uncommon [2]. The size of most lesions ranges from 5 mm to 15 mm in diameter. However, three cases of a giant variant of FSCH showed the lesions could reach 10 cm to 15 cm in diameter [4]. Three cases of secondary FSCH were reported, two arising in a giant nevus, lipomatous superficialis, and another in a port-wine stain [3]. Because of a lack of distinctive clinical features, the initial clinical diagnosis of FSCH in all reported cases has included many other skin diseases, such as nevus sebaceous, sebaceous hyperplasia, trichofolliculoma, nevus lipomatosus superficial, lipoma, neurofibromas, and so on. The definitive diagnosis is made mainly based on the histological features. FSCH shows irregular infundibular cysts with sebaceous elements and laminated keratin material, inferior follicular segments in various stages of regression and remains. Many sebaceous lobules are connected to the infundibular cysts via sebaceous ducts. Dense fibrillary bundles of collagen are lined surrounding hair follicles and sebaceous follicles. FSCH usually demonstrate an equal proportion of epithelial and stromal structures. Occasionally, other elements, such as mature adipocytes, blood vessels, mucin, hair shaft fragments and thickened nerve bundles, have been described [4, 5]. Recently, Saadat et al. [6] reported a case of FSCH with well-formed smooth muscle as its only mesenchymal component, and named the new variant folliculosebaceous smooth muscle hamartoma.

To our knowledge, this case represents the first reported case of inner canthus FSCH. The majority of FSCH lesions are treated by simple excision without recurrence. But in our case, it recurred 2 years later after the first excision at the age of 16, and did not recur 3 years after the second excision at the age of 34. Whether surgical excision after adolescence can reduce recurrence is under investigation.

Acknowledgements

References

2 Sturtz DE, Smith DJ. Giant folliculosebaceous cystic hamartoma of the upper extremity. J Cutan Pathol 2004; 31: 287-90.

3 Kang H, Kim SE, Park K, et al. Nevus lipomatosus cutaneous superficialis with folliculosebaceous cystic hamartoma. J Am Acad Dermatol 2007; 56 (2 Suppl): S55-S57.

4 Toyoda M, Morohashi M. Folliculosebaceous cystic hamartoma with a neural component: an immunohistochemical study. J Dermatol 1997; 24: 451-7.

5 Yamagata K, Mitsuishi T, Kawana S. Folliculosebaceous cystic hamartoma with hair shaft fragments. Eur J Dermatol 2005; 15: 105-6.

6 Saadat P, Doostan A, Vadmal MS. Folliculosebaceous smooth muscle hamartoma. J Am Acad Dermatol 2007; 56: 1021-5.