Dog Breast Cancer

The most common form of cancer in female canines that haven’t been neutered is the dog breast cancer. The tumors may be small nodules that may migrate towards other areas of the body and may metastasize in the lymph nodes or the lungs. If detected in a timely manner, breast cancer can be treated and the tumors may be eliminated.

Dogs Affected with Breast Cancer

Female dogs are more exposed to developing mammary cancer. The unsprayed females are more susceptible to cancer; dogs that have been spayed before their first heat cycle have a very low incidence of mammary tumors. The presence of hormones (estrogen and progesterone) increases the risk of breast cancer.

The breast cancer affects dogs between the age of 5 and 10, the tumors being present mostly in females; in rare cases, male dogs have breast cancer.

Types of Breast Tumors

The breast tumors may be of several types. Over 45% of mammary tumors are benign and may be adenomas of different types or duct papillomas. The malignant tumors may be adenocarcinomas, fibrosarcomas or mixed tumors.

A biopsy can determine is the tumor is benign or malignant. If the tumor is malignant, this means that the tissues are cancerous and may spread to other parts of the body.

Symptoms of Breast Cancer

A tumor may be identified through palpating the mammary glands of the dog; the dog has 5 mammary glands that are located on the lower part of the abdomen. The tumor will be felt as a swelling or multiple swellings. The malignant tumors may grow rapidly and have irregular shapes; a pea sized tumor may double its size in 1 month. 

The tumors may bleed.

The detection of breast cancer can only be done by performing a few biopsies and x-rays.

Treatment for Breast Cancer

If the tumor is detected in time and it is not extended, it may be removed through surgery. The surgery is recommended for all patients, unless the dog is very old. In this case, only supportive treatment can be offered.

Surgery may treat the breast cancer in approximately 50% of cases. The vet will extract additional skin tissues from the tumor’s area, to ensure that all the malignant cells are removed. If the tumors affect the lymph nodes, these should also be removed.

In some cases, the tumor may grow back; the vet will also recommend chemotherapy and radiation therapy to prevent the migration of the cancerous cells through other areas of the body. However, in breast cancer, chemotherapy isn’t as effective as in other types of cancer.

Spaying is also recommended, so as to prevent the secretion of additional hormones. This may prevent the re-growth of the tumor.

Anti hormonal drugs may also be administered.

Preventing Breast Cancer

Breast cancer in dogs may be prevented through spaying the dog as early as possible. The risk of developing breast cancer increases with each heat cycle.

Visit the vet as soon as you detect a swelling in the breast area.