Mammary Gland Tumors - Dogs
About one-half of mammary gland tumors are malignant, and half are benign. Spaying dogs at early age decreases the risk of having this type of cancer to 0.5% if dogs spayed before the first heat, second to 8.0% if Spayed before second heat compared to intact bitch.
Benign Mammary tumors are usually noticed as small slow-growing masses. Malignant tumors are usually growing faster, single or multiple masses, sometimes ulcerated. Metastasis is a sign of the aggressive tumors and can spread to any organs particularly lung, the adjacent mammary glands, and lymph nodes.
The definite diagnosis can be achieved by histopathology. However veterinarians always request chest & abdominal X-ray for further assessment and before starting any treatment.
This cancer can be surgically removed by different methods depends on size, location, single or multiple, number of mammary gland & lymph nodes invaded. For example, vets can choose between simple lumpectomy, removing one or two mammary glands, all chain mammary glands in one or both sides. A radical mastectomy means all the breasts, the skin covering them, and the lymph nodes are all removed at one time.