Auricular Squamous Cell Carcinoma in Dogs
Dogs can be afflicted with several types of skin tumors, including on the ears. One type of tumor that can affect the ears is a squamous cell carcinoma. A squamous cell carcinoma (SCC) can be described as a malignant and particularly invasive tumor that takes hold in the scale like cells of the epithelium – the tissue that covers the body or lines the cavities of the body. These scale like tissue cells are called the squamous.
Carcinoma is, by definition, an especially malignant and persistent form of cancer, often returning after is has been excised from the body and metastasizing to other organs and locations on the body.
An auricular (relating to the ear) squamous cell carcinoma may be caused by excess sun exposure. It is more common in white dogs, dogs with light hair coats, and in dogs that have white ears. This type of tumor starts out as red, crusty looking areas on the tips of the ears. The sores, or ulcers, may seem to come and go and will slowly get bigger with time. There may be ulcers on the face as well. This type of cancer can be treated successfully if it is caught early. This is a rare form of cancer in dogs and can be treated successfully if it is caught early.
Symptoms and Types
- Red, crusty sores on the edges of the ears
- Redness may come and go
- Bleeding from sores on the ears
- Sores on the ear that slowly get bigger
- As sores get larger, ear tips may disappear, ear may become malformed
- Sometimes, sores on the face
- Excessive exposure to the sun over a long period
You will need to provide a thorough history of your dog's health leading up to the onset of symptoms. Be sure to describe any sores that have been apparent on other parts of the body, even if you suspect they were caused by injuries resulting from outdoor activity, or from scratching at the skin.
During the examination, your veterinarian will look carefully for other sores or tumors on your dog's body. The lymph nodes will be carefully felt to determine if they are enlarged, an indication that the body is reacting to an infection or invasion. A sample of lymph fluid may be taken to test for cancerous cells. Your veterinarian will order complete blood count and biochemistry profile to make sure your dog's other organs are working normally and to determine whether the white blood cell count is higher than normal; again, an indication that the body is fighting an invasive disease or infection.
A biopsy will be taken of the ulcerated tissue on your dog's ear so that your doctor can diagnose the specific type of growth it is, whether carcinoma or a benign mass of tissue. This is necessary for differentiating the ulcers from any other condition that could be causing the same symptoms. X-rays images of your dog's chest and skull will allow your veterinarian to visually inspect the lungs for signs of any abnormalities, especially tumors, and to make sure that the carcinoma has not spread into the bones.
Treatment will depend on how many ulcers your dog has on its ears and how large the ulcers are. If there is only one small ulcer, it may be removed by cryosurgery, a freezing technique. If the ulcer is larger, or if there are several ulcers, it/they will be treated with surgery. During surgery, most or all of the upright or floppy part (pinna) of your dog's ear will be removed. In some cases, the ear canal may also need to be removed. Most dog's recover well from this surgery, even if the ear canal needs to be removed.
If surgery is not a practical option, chemotherapy may be used to kill the cancerous cells. However, chemotherapy is not usually as effective as surgery. In some cases, your veterinarian may recommend a veterinary cancer specialist so that you can determine if there are other viable treatment options.
Living and Management
Once your dog has recovered from surgery, it should be able to lead a normal life. Your dog's appearance may be different, but it will adjust easily to its changed body. You will need to monitor your dog closely to make sure it does not develop new sores on its face or head. Try to limit the amount of time your dog spends out in the sun. If you must let your dog out during the daytime, you will need to apply sunscreen to areas of the body that have a thin hair coat and limit the time spent in the sun. If your dog tends to spend a lot of time near a glass door or window, you might place a shade or reflector over the glass to block ultraviolet (UV) rays from reaching your cat. As with any cancer, it is recommended that you take your dog for regular progress check with your veterinarian.
Limit the amount of time your dog spends in the sun, especially if it is white dog, or if it has a lighter hair coat. When your dog does go out in the sun, apply sunscreen to its ears and nose.