Tumor is a scary word, especially when you see one in your dog's ear. However, before you get worried, consider that Johns Hopkins Medicine notes tumor doesn't necessarily mean it's cancer; tumor is a mass. The appearance of the mass, as well as its location, can clue you in about what kind of tumor you've spotted in your dog's ear.
Many Places to Grow
Your dog's ear has four parts vulnerable to tumors: the pinna, external ear canal, the middle ear and the inner ear. His earwax and oil-producing glands, middle and outer layers of skin, bones, muscles and connective tissues can all support tissue growth. Tumors are more common in the external ear canal and pinna than in the middle and inner ear; ear canal tumors are typically malignant.
Your first clue your dog may have a tumor in his ear likely will be more ear scratching than usual or lots of head shaking. He may exhibit some signs of hearing loss, and depending on the location of the tumor, he may show some signs of vestibular impact, such as loss of balance, head tilting and difficulty blinking.
Ear tumors can take on a variety of forms. Some are flat lesions, some are lumps perched on stalks and others are masses filling the ear canal. Common colors include white, pale pink, purple and black -- sometimes housing a dark, oily fluid. Bleeding is routine and it's not unusual to see a pus-filled or bloody discharge accompanied by a foul odor.
The Vet Makes the Call
When you find a tumor in your dog's ear, have your vet take a look. Malignant tumors have a greater tendency to bleed and be ulcerated, however, benign tumors may bleed as well. Ceruminous gland adenocarcinoma is the most common malignant ear tumor, followed by squamous cell carcinoma. Benign tumors include basal cell tumors, inflammatory polyps and papillomas. The vet will take a tissue sample to determine definitively whether a lump is malignant or benign. Surgery is the treatment of choice for all tumors, sometimes including laser surgery. If the tumor is cancerous, other treatment may be necessary, such as radiation therapy and chemotherapy.
Inflammation: the Path to Tumors
According to the Merck Manual Pet Health Edition, the cause of ear canal tumors isn't known, but long-term inflammation of the ear canal is suspected to give rise to unusual growth and tissue development, ultimately resulting in a tumor. Dogs with drooping or floppy ears may be predisposed to ear tumors because his ear canals are always moist, providing a happy breeding ground for yeast and bacterial infections. Infections can give way to inflammation, sometimes resulting in benign or malignant tumors.
- The Merck Manual Pet Health Edition: Tumors of the Ear Canal in Dogs
- VCA Animal Hospitals: Ear Tumors
- Clinical Oncology Service Ryan Veterinary Hospital of the University of Pennsylvania: Ear Canal Tumors in Dogs and Cats
- Pet Cancer Center: Ear Canal Tumors in Cats and Dogs
- PetPlace.com: Ear Tumors in Dogs
- Johns Hopkins Medicine: What Are Tumors?