A Case of Malignant Proliferating Trichilemmal Tumor with Spindle Cell Carcinoma

Proliferating trichilemmal cyst(proliferating trchilemmal tumor, PTC) most commonly occurs in the scalp and is generally benign. Malignant transformation of PTC is rare, and the appearance of a spindle cell(sarcomatoid) carcinoma is extremely rare. The authors experienced a case of malignant proliferating trchilemmal tumor with spindle cell carcinoma on the scalp in a 41-year-old male. The tumor was widely resected and covered with split thickness skin graft after Terudermis(R) graft. Imaging studies and fine needle aspiration cytology showed no regional lymph node involvement or distant matastasis.

A Case of Proliferating Trichilemmal Cyst with Trichoepitheliomatous Change / 대한피부과학회지

Proliferating trichilemmal cyst(PTC) is a rare benign neoplasm that is thought to be derived from the outer root sheath of anagen hair follicles differentiating toward the infundibular and matrical segments, sebaceous glands, apocrine glands, or acrosyringium. Clinically, it presents as a solitary elevated, lobulated mass on the scalp of elderly women. Histologically, it shows well demarcated multiple lobules of squamous epithelium. The center of the lobule undergoes abrupt keratinization without formation of keratohyalin and foci of calcification are often present in the areas of amorphous keratin. PTC can be associated with sebaceous nevus of Jadassohn, ectopic apocrine sweat glands, spindle cell carcinoma, etc. We report an unusual case of proliferating trichilemmal cyst with trichoepitheliomatous change in a young woman.

A Case of Proliferating epidermoid cyst / 대한피부과학회지

Proliferating cutaneous epithelial cyst is classified into two subtypes, proliferating trichilemmal cyst and proliferating epidermoid cyst, depending on the mode of keratinization or the origin of the tumors. Proliferating epidermoid cyst is a subepidermal cystic tumor showing, at least in focal areas, a cystic wall lined by epithelium typically seen in epidermoid cyst. We report a case of proliferating epidermoid cyst in a 58-year old man who had a 3x4 cm sized egg shaped cystic tumor on the occipital area of the scalp. Histopathologic examination revealed the tumor was a large epidermoid cyst and a portion of epithelial proliferation projected from the cyst wall into the dermis. The epithelial proliferation was surrounded by paucicellular fibrous stroma.

A Case of a Proliferating Trichilemmal Cyst With Unusual Clinical Features

The proliferating trichilemmal cyst is a rare, usually benign tumor of external root sheath origin. About 90% of the cases gccur on the scalp, with the residual 10% occurring mainly on the back. More than 80% of the patients are women, most of whom are elderly. The cysts are commonly large, measuring up to 6 cm or more in diameter. A 33-year-old woman visited our department with a history of a matchhead- sized erythematous tender papule on her left knee that had been present for two years. A histopathological examination revealed a well-circumscribed, multilobulated cystic tumor with trichilemmal keratinization in the dermis. There were individual cell keratinization and focal calcification in some areas. This case was diagnosed as a proliferating trichilemmal cyst. This case was very unusual not only because the tumor occurred on the knee as a matchhead-sized papule but also because of her young age at presentation.

Two Cases of Proliferating Trichilemmal Cyst / 대한피부과학회지

We report two cases of proliferating trichilemmal cyst in a 61-ear-old woman and a 44-year-old woman who had a solitary tumor, on the left temporal area of the scalp and right flank, respectively. Histologically, the tumors were localized in the dermis and corisised of multilobulated cysts. The cyst walls were composed of liquamous epithelium showing trichilemmhl keratinization. Some of the cells had clear cytoplasm and were positive on PAS staining. Individiial cell keratinization, mild nuclear atypia were also found in the cyst walls. For the treatment, surgical excision was performed with sufficiert margin.