cancer
-
Clinical features •May present as an intraepidermal lesion (hidroacanthoma simplex, a dermal tumor (dermal duct tumor) or as both with epidermal continuity (poroma); some tumors overlap hidradenoma & poroma (poroid hidradenoma overlap) •Solitary skin colored, erythematous or pigmented, generally asymptomatic nodule with a predilection for the foot but it may occur just about anywhere •M=F…
-
Trichilemmoma is a tumor showing differentiation towards the follicular external root sheath. It may be solitary, multiple or constitute a features of autosomal dominant, Cowden (multiple hamartoma) syndrome when very numerous lesions are present. The last is associated with germline mutations in the PTEN tumor suppressor gene in the majority of patients. Solitary lesions do…
-
A relatively common benign sweat gland tumor characterised by an admixture of epithelial & mesenchymal elements. Typically thought of an apocrine gland tumor. Some authors recognise an eccrine variant. In my experience, such tumors are exceptionally rare. Many tumors show an admixture of both elements. Mixed tumor of the skin is mostly associated with rearrangment…
-
Trichoepithelioma is a hamartoma comprising a basaloid/germinative component and a prominent perifolliclular sheath proliferation. It may present as a solitary lesion or as multiple, familial lesions in multiple familial trichoepithelioma (which is probably a variant of Brook-Spiegler syndrome) & Brook-Spiegler syndrome. Clinical features •Solitary trichoepithelioma presents as a flesh-colored papule or nodule (<1.0 cm) most…
-
Sebaceous hyperplasia Clinical features •This is common and presents as single or commonly multiple, yellow dome-shaped umbilicated papule(s) (1-2 mm diameter) on face of the elderly but may occur on the chest, the caruncle, external genitalia & areola •M>F •Increased incidence with cyclosporine Histological features •Lobules drain into a dilated follicle •Lobules are increased in number but do not…
-
Although desmoplasia may exceptionally be encountered in banal/common and congenital nevi, the overwhelming majority of cases represent sclerosis in Spitz nevi. Desmoplastic blue neves is discussed in a separate blog. Desmoplastic nevus arising on chronic sun-damaged skin has also been described. Clinical features Desmoplastic Spitz nevus presents as a usually small, erythematous papule or nodule…
-
Clinical features •In the older literature also known as juvenile melanoma, spindle & epithelioid cell nevus •First described by Sophie Spitz in 1948 •Approximately 1% of nevi in children •Most often presents in children & adolescents but may be seen the middle aged •Although cases have been documented in the elderly, I would advise extreme…
-
Nevi presenting in the genitalia, inguinal region, umbilicus, axilla and breast may show considerable atypia. They should be readily recognised, often at scanning magnification but may be misdiagnosed as melanoma if the age of the patient and site of the lesion are not taken into account. So-called atypical acral nevus, ear & scalp nevi are…
-
In the older literature this lesion has previously been called epithelioid blue nevus, animal type melanoma, pigment synthesizing melanoma & equine melanoma. Indeed, my cases of so-called animal type melanoma were re-classified as pigmented epithelioid melanocytoma during the preparation of the seminal paper on the topic by Zembowicz & Carney. Clinical features •Most common in…
-
•Extremely rare often amelanotic, high-grade variant (based on the majority of documented cases representing metastases. The biological potential of primary tumors with rhabdoid features is uncertain owing to the paucity of reported cases) •Metastases & recurrent disease>>primary tumors •Characterized by pleomorphic tumor cells with large eosinophilic, hyaline globular inclusions and eccentric vesicular nuclei containing prominent nucleoli, mitoses often conspicuous •Inclusions predominantly composed of vimentin intermediate filaments •Immunophenotype is variable with possible loss of expression…
McKee Derm 