Parameatal cyst, paraurethral cyst, genitoperineal cyst, mucoid cyst • Midline developmental cyst found at any point from external urethral meatus to anus Etiology/Pathogenesis • Defective embryological closure of median raphe Abnormal closure…
Clinically presents as large, erythematous patch (median: 7 cm) Endothelial multilayering and nuclear atypia Mitotic figures often present Evidence of MYC amplification by FISH or immunohistochemistry • Hobnail hemangioma • Lymphangioma circumscriptum…
Other types of HPV (18, 31, 32, 33, 34, 35, 39, 42, 48, 51, 52, 53, and 54) have also been implicated Clinical Issues • Often multifocal • Benign-looking papules and macules…
Inherited mutations in EVER1/TMC6 or EVER2/TMC8 lead to susceptibility to HPV infection Increased risk for development of in situ and invasive SCC Clinical Issues • As most cases are benign, aggressive…
Subcutaneous or dermal mass • Excellent prognosis, no malignant potential • Complete excision is curative but not necessary given benign nature of lesions Microscopic • Well-circumscribed vascular proliferation • Vessels are thin-walled and closely…
Proliferation of atypical keratinocytes typically confined to basilar 1/3 of epidermis Overlying parakeratosis and basilar budding usually seen • Solar lentigo (lentigo senilis) Elongated, hyperpigmented rete ridges Lacks keratinocyte atypia/pleomorphism • Seborrheic…
Glandular differentiation is often present; not as common as in benign mixed tumor of skin Irregular nests, cords, and sheets of cuboidal or polygonal cells Foci of highly atypical cells…
Lacks thick-walled vessels • Cavernous hemangioma Ectatic, thin-walled vessels • Venous hemangioma • Venous lake Single, dilated, thin-walled vessel • Angioleiomyoma Syncytial proliferation of vascular smooth muscle Low-Power Image of Arteriovenous HemangiomaLow magnification of…
EMH With MegakaryocyteThis is a skin biopsy specimen with extramedullary hematopoiesis (EMH), as evidenced by the large megakaryocyte . EMH With Erythroid CellsThis cutaneous lesion contains small clusters of nucleated…
Granular cell tumor Lymphoma • Reaction pattern in certain inflammatory conditions such as Lichen planus Lupus erythematosus • Reaction pattern overlying certain infections Particularly deep fungal • Reaction pattern overlying tattoos Particularly red…
