Hereditary trichilemmal cysts. HEREDITARY PILAR CYSTS

Abstract

Summary One hundred and fifteen individuals from 60 families are described who had trichilemmal cysts. These were solitary or multiple intradermal cysts and occurred most frequently on the scalp. A punctum leading from the skin surface to the cyst was not seen in any patient. Because they are encapsulated they are easily removed. Histologicaily they resemble the external root sheath in the region of the follicular isthmus and are quite different from epidermoid cysts. They are not associated with Gardner's syndrome or any other diseases. In 46 of the 60 families an autosomal dominant mode of inheritance was demonstrated.

Mapping of hereditary trichilemmal cyst(TRICY1)to chromosome 3p24-p21.2 and exclusion of β-CATENINandMLH1

“…It occurs predominantly on the scalp [McGavran and Binnington, 1966;Pinkus, 1969], is easily enucleated and appears as a firm, smooth, whitewalled cyst without a punctum [Leppard and Sanderson, 1976;Leppard et al, 1977]. Benign, relatively uncommon, invasive proliferating trichilemmal tumors [Naik et al, 1990;Hendricks et al, 1991;Laing et al, 1991;Reis et al, 1993;Sleater et al, 1993] and rare cases of metastasizing proliferating trichilemmal cysts [Weiss et al, 1995;Park et al, 1997] have been reported.…”

“…Benign, relatively uncommon, invasive proliferating trichilemmal tumors [Naik et al, 1990;Hendricks et al, 1991;Laing et al, 1991;Reis et al, 1993;Sleater et al, 1993] and rare cases of metastasizing proliferating trichilemmal cysts [Weiss et al, 1995;Park et al, 1997] have been reported. This is an autosomal dominant trait [Leppard et al, 1977], but it does not yet have its separate entry in the OMIM database. In this study we report assignment of the first locus for TRICY1 and mutation screening data on two candidate genes, CTNNB1 and MHL1.…”

Numerous Recurrent Trichilemmal Cysts of the Scalp

“…10,13,34 Trichilemmal cysts differ from epidermoid cysts in that they do not have an overlying punctum and they rarely become inflamed. 16,30 Certain reports in the literature suggest and describe findings seen in certain imaging or cytologic studies done for this pathology. These studies are suggested whenever a malignant degeneration is suspected by history and physical examination or for differential diagnosis with other pathologies or more serious entities such as meningocele or enphalocele.…”

“…Several reports in the literature about trichilemmal cysts have been written describing the natural history and nomenclature 19,30 ; the ultrastructural, cytologic, and histologic description 15,31Y36 ; the hereditary component 5 ; the potential of transformation into a proliferating trichilemmal cysts or malignant degeneration 4,14Y16,20Y22,27,29 ; the surgical techniques for removal 15,37,38 ; the imaging modalities for diagnosis 39 ; and the unusual presentations in several case reports. 6,40Y42 More than 60 of these published studies were reviewed.…”

Surgical Pearl: Peripheral crescentic excision with hinge flap for treatment of pilar cysts

“…1 In lesions that are not inflammed and small, simple extraction is usually performed through the use of a small overlying elliptical incision or through access using a 3 mm to 4 mm punch. 2 Larger cysts, especially those greater than 1.5 cm to 2.0 cm, often act as tissue expanders, creating overlying skin redundancy requiring removal in order to achieve a smooth contour.…”