Dermoid cyst (Nova - Orin x Luna daughter)

A dermoid cyst on a dog's head is a benign, congenital growth that develops from misplaced skin tissue during embryonic development. These cysts can contain hair, sebum, and keratin. They are more common in certain breeds like Rhodesian Ridgebacks and Kerry Blue Terriers. While generally harmless, they can cause problems if they become large or infected.

Once clipped they were far more pigmented than expected.

Histology report MICROSCOPIC DESCRIPTION  The sections comprise epidermis overlying dermis which contains parts of a large intradermal multilobulated epidermal-lined cyst / cysts which contains finely laminated keratin and hair shafts, and are lined by epithelium retaining its granular layer. Adjacent hair follicles appear largely normal. A lesion free margin is present in the sections examined i.e. assuming that the sections are representative of the margins then this extirpation appears to be complete. DIAGNOSIS Dermoid cyst

 COMMENT The changes are consistent with a dermoid cyst or cysts. These are embryonic remnants and the lesion usually occur along the dorsal midline particularly on the head. Complete surgical excision should be curative.