Disease Ontology ID: DDTO:0000607

Disease Description: A small growth, usually on the face, filled with keratin material.

Inherit Mode: -

Disease Symptom: Keratoacanthomas develop most commonly on the back, tail and neck.The neoplasm generally appears as a well-circumscribed dermal or subcutaneous mass ranging in size from 0.4 to 4 cm in diameter, with a pore that opens to the skin surface. The pore may be filled with inspissated keratinous material which can be expressed by appying digital pressure to the mass. A keratinised plug may protrude from the pore and, if large, may appear as a cutaneous horn.If the neoplasm does not communicate with the skin surface it appears as an encapsulated intradermal mass. If the tumour wall becomes disrupted, keratin leaks into the surrounding tissues, evoking a foreign body reaction and a severe inflammatory response.The condition usually presents as a solitary lesion, however it may be generalised in which case a large number of nodules can be found.

Disease Cause: -

Disease Diagnose: Diagnosis is based on excisional biopsy and subsequent histopathologic examination.The pore is lined by stratified squamous epithelium with intracytoplasmic keratohyalin granules. From the base of the pore, the tumour extends into the dermis and subcutis. There is central aggregation of keratin.The wall of the tumour consists of large, pale-staining keratinocytes. Compression of the surrounding dermal collagen produces a pseudocapsule.No evidence of malignancy is seen, the tumour is benign.

Treat Method: Surgical excision is the treatment of choice for solitary lesions. The tumour does not usually recur, however dogs can be prone to developing additional tumours over time.In generalised forms, surgical excision is often not possible.Topical or systemic antimicrobials might be necessary if secondary bacterial infection occurs.Oral retinoids such as isoretinoin or acitretin can prevent the development of new lesions and cause regression of small lesions. Larger lesions can be pretreated with cryotherapy to give better results. Lifelong administration might be necessary.

Breeder Advice: -

Disease Description Source: -