glycogen and Hair-Diseases

Sebaceous carcinoma (SC) most commonly presents on the eyelid and is frequently misdiagnosed both clinically and pathologically. Only very rare cases of desmoplastic tricholemmoma (DTL) of the eyelid have been reported.. We present a case of DTL of the eyelid initially misdiagnosed as an invasive SC.. A 55-year-old man presented with a rapidly growing 5 mm erythematous lesion on his upper eyelid. Histologic examination showed a lobular, folliculocentric proliferation of palely eosinophilic to clear cells surrounded by peripheral basal cells with palisading. The central portion of the lesion appeared infiltrative with clear cells surrounded by a thickened basement embedded in a dense, collagenous stroma. However, the cells showed mostly uniform cytoplasmic clearing, lacking the multivacuolization or nuclear scalloping of sebocytes. In addition, a periodic acid Schiff stain was positive with diastase sensitivity, indicating cytoplasmic glycogen, not lipid. CD34 immunohistochemical staining was also positive, which has been reported in DTL but not in SC.. SC is often misdiagnosed as other entities, but misidentification of other neoplasms as SC is less common; however, this is an important diagnostic pitfall, as it may result in unnecessary and disfiguring surgical treatment and consequent medical-legal liability. Therefore, DTL should enter the differential diagnosis of clear-cell neoplasms on the eyelid.

Topics: Adenocarcinoma, Sebaceous; Antigens, CD34; Biomarkers, Tumor; Diagnosis, Differential; Eyelid Neoplasms; Glycogen; Hair Diseases; Hair Follicle; Humans; Male; Middle Aged; Skin Neoplasms

We describe 13 cases of tricholemmal carcinoma, a rarely recognized cutaneous adnexal neoplasm. The patients were nine men and four women. In general, the tumors presented as slow-growing epidermal papules, indurated plaques, or nodules showing predilection for sun-exposed, hair-bearing skin. The lesions were most frequently misdiagnosed clinically as basal cell carcinoma. Histologically, they showed a variegation of growth patterns including solid, lobular, and trabecular; they were characterized by a proliferation of epithelial cells with features of outer root sheath differentiation, including abundant glycogen-rich, clear cytoplasm, foci of pilar-type keratinization, and peripheral palisading of cells with subnuclear vacuolization. Because of their variable growth pattern, overt cytologic atypia, abundant clear cytoplasm, occasional pagetoid intraepidermal spread, and brisk mitotic activity, these tumors may pose difficulties for diagnosis and be confused with other malignant skin tumors with clear cell changes. Despite the seemingly malignant cytological appearance of these lesions, clinical follow-up in 10 cases showed no recurrence or metastasis over a period of 2-8 years. Thus, conservative surgical excision with clear margins appears to be the treatment of choice for these neoplasms.

Topics: Adult; Aged; Aged, 80 and over; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Cytoplasm; Diagnosis, Differential; Epidermal Cyst; Epithelium; Female; Follow-Up Studies; Glycogen; Hair Diseases; Humans; Keratins; Male; Middle Aged; Mitosis; Neoplasms, Basal Cell; Skin Diseases; Skin Neoplasms; Vacuoles

Topics: Adolescent; Atrophy; Basement Membrane; Child; Child, Preschool; Connective Tissue; Edema; Epidermis; Epithelium; Female; Glycogen; Hair; Hair Diseases; Humans; Male