Hair follicle tumors of the skin

Malignant hair follicle tumors of the periorbital region: A review of literature and suggestion of a management guideline

Malignant hair follicle tumors are rare skin adnexal malignancies that have a predilection for the head and neck region. They can be categorized into a number of different subtypes. Histologically, they are distinct from their benign counterpart. To the best of our knowledge, there is no extensive review of these malignancies, especially in the periorbital region. We aim to provide a literature review and a guideline for management of these malignant tumors in the periorbital region. Database from Medline, PubMed, Embase, and Google Scholar were consulted. A total of 16 cases from the literature on hair follicle malignancies in the periorbital region were included in this review. The clinical presentations, diagnostic patterns, investigations used, and best management approach of these tumors are discussed. The American Joint Committee on Cancer (AJCC) 7(th) edition carcinoma of the eyelid staging system was used to describe their behaviors. We recommend wide excision surgery and a close follow-up for these tumors. Tumors presenting with a late stage require work-up for distant metastasis and consideration for exenteration procedures. The role of radiotherapy and chemotherapy in this context is still uncertain.

Hair follicle nevus in a 2-year old

We report a 2-year-old boy with an elastic soft, flatly elevated, skin-colored nodule on his nasal ala. Histologic examination revealed numerous small hair follicles in several stages of maturation in the dermis. Serial sections did not show any cartilage or a central epithelial lined cystic structure. Based on clinico-pathologic findings, we diagnosed this lesion as a hair follicle nevus. Hair follicle nevus is quite rare. Histologically, it is very important not to find cartilage or a central epithelial lined cystic structure for distinction from an accessory auricle and from a trichofolliculoma, respectively. Awareness of the clinical and pathologic characterization of hair follicle nevus is an aid to a correct diagnosis.

Psoriasis-like dermoscopic pattern of clear cell acanthoma

BACKGROUND

Dermoscopy provides additional criteria for the diagnosis of skin lesions.

OBJECTIVE

To investigate the dermoscopic aspect of clear cell acanthoma (CCA).

METHODS

Six consecutive cases of CCAs were observed under conventional dermoscopy (Case 1-4) or videodermoscopy (Case 5-6).

RESULTS

Common dermoscopic findings were: (i) squamous surface with translucid collarette; (ii) dilated capillary loops, mainly perpendicularly orientated to the skin surface, as dotted, pinpoint-like structures, regularly distributed in a reticular array over the surface.

CONCLUSIONS

The vascular psoriasis-like dermoscopic findings seem to be a clue for CCA and provide evidence of an inflammatory process for CCA formation.

Dilated pore: a case report and an immunohistochemical study of cytokeratin expression

We report a 71-year-old Japanese female with a dilated pore in the form of a nodule above her right eyebrow. Histologic examination revealed a flask-shaped, keratinous cystic structure that was continuous with the surface epidermis and had numerous elongated rete ridges in the lower portion. An immunohistochemical study using a panel of monoclonal antibodies against cytokeratins (CKs) and involucrin detected CK1 and CK10 in the suprabasal cells of the cystic structure. CK8 and CK19 expression was observed in the outermost layer of some elongated rete ridges; it was composed of pallisading columnar cells. Most parts of the outermost layer of the cystic structure stained positively with AE1 antibody. From these immunohistochemical findings, we speculated that the dilated pore in our case was an isolated clinical entity is a follicular tumor differentiating mainly toward the infundibulum and partly toward the isthmus.

A case of malignant proliferating trichilemmoma of the scalp with multiple metastases

We report a case of malignant proliferating trichilemmal tumor showing multiple distant metastases. The patient demonstrated a round mass in the right occipital area for 12 months and the lesion grew rapidly to assume 8 x 6.5 x 4 cm in diameter, with areas of superficial erosion and crusting within the recent 3 months. The entire lesion was removed with a wide surgical excision. It recurred on the neck area 4 months after excision and the lesion was removed with surgical resection again. There was evidence of multiple metastases on CNS and mediastinal lymph nodes after 6 months. The patient was treated with cisplatin and etoposide combination chemotherapy and a partial response was achieved.

A clear cell pilar sheath tumor of scalp: case report

A long-standing tumor of scalp is reported characterized histologically by extensive proliferation of pilar epithelium made up exclusively of cells with small round nuclei and clear cytoplasms containing glycogen granules. The tumor epithelium showed no tendency for keratinization and no cytologic atypia. The growth, however, appeared aggressive and replaced the entire thickness of the dermis and extended into the subcutaneous fat tissue.

Malignant proliferating trichilemmal tumors--report of three cases

We are reporting three patients with recent history of rapid enlargement of long standing nodular scalp lesions. Histologic sections revealed areas of relatively benign proliferation of pilar sheath epithelium and foci of trichilemmal keratinization characteristic of a proliferating trichilemmal cyst. There were also extensive areas of severe cellular dysplasia and surrounding dermal invasion indicating malignant transformation.