Diseases of the nasal planum

The most common clinical sign for owners to seek veterinary care in reference to the nasal planum is depigmentation in dogs and ulceration in cats. Proliferative (nodular) diseases are less common in dogs than in cats, because cats are more prone to develop squamous cell carcinoma of the nasal planum. Because a wide variety of diseases may present with similar clinical signs, the most helpful diagnostic test (after a thorough history and physical examination) is a skin biopsy. Discoid lupus erythematosus is the most common disease affecting the nasal planum of dogs in the author's practice.