Nailbed Epithelial Inclusion Cysts in Two Dogs

A 5-year-old, 6.2 kg male mixed dog was presented to local animal hospital with a 6-month history of swelling, pain, inflammation, and lameness in the 5th digit of right hind limb. And a 7-year-old, 2.7 kg male Maltese dog was also presented to animal hospital with a 2-month history of nail deformities in the 5th digit of left hind limb. Abnormal growth or degeneration of the distal phalanges was observed at the 5th digit of hind limb in two dogs using radiographic examination. The masses in the digit were excised completely under local anesthesia. On histological examination of the digit masses, large well-circumscribed, unencapsulated round or irregular cystic neoplasms with/without inflammation were occupied in or adjacent area of the distal phalanx. These cysts were lined by stratified squamous epithelium that occasionally had a prominent granular cell layer. Based on the history, clinical signs, radiographic, gross and histopathologic features, these cases were diagnosed as nailbed epithelial inclusion cysts in the digit of dogs.