Cancer: Mammary

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Different theories prove that oncornoviruses, hormonal imbalance and not the spaying of females are some of the causes of  mammary cancer in dogs. The exact mechanism that triggers cancerous development is unknown. Genetic factors and possible nutritional effects might be some other reasons. Since genetics and nutrition are not clinically monitored by a veterinarian, it is not practical to use these factors in predicting the development of mammary cancer.


More then 50% of dog mammary cancer cases are either benign (stable, treatable) or benign mixed cancerous developments. Few cases have been reported as being truly malignant in nature. It is believed that most of the benign mixed types of dog mammary cancer are potentially malignant and even malignant types remain benign during the initial stages of cancer development.

According to the World Health Organization (WHO), mammary cancer in dogs may be classified as carcinomas, sarcomas, carcinosarcomas and benign adenomas. Each of the primary types of cancer mentioned have various sub types and varies in different canine species.


Not all progressively growing swellings and masses in the mammary glands can be possibly be mammary cancer. On physical palpation, these appear either as rigid masses or as painful swellings. They are either nodular masses or irrationally distributed swellings across the mammary glands.

Developments in size and appearance of rigid masses and swellings should be closely monitored, as cancers grow fast and can be differentiated from hyperplasia (abnormal increase in normal cells) clinically.

If a hormonal imbalance is noted along with mammary gland swellings, it likely represents either a developing or mature canine mammary cancer. Specific signs of hormonal imbalance may vary with the dog specie and based on the extent of cancerous development.


Physical examination can help in identifying tumors on the mammary gland. Similarly, close monitoring of nodule development can confirm that they are tumors. Associated lymph nodes (inguinal and axillary) should be thoroughly palpated (touched) and examined for any rigidness and swelling to estimate metastatic status of canine mammary cancer.

A detailed biopsy and radiography are also confirmatory tools, and should be done once mammary gland swellings are suspected as cancer. Earlier and timely confirmation can help in improving the prognosis index and effectiveness of treatment plans selected.


As most cases of canine mammary cancers are benign in nature, surgical elimination has been proven to be the most effective treatment option. Different surgical approaches such as lumpectomy, mastectomy (simple, radical) etc are practiced, but it is yet to be determined which of these modes are most successful. Simpler and approaches that have some historical precedent are prioritized.

Chemotherapy is used, but practically this type of treatment is considered not effective. Detailed studies regarding the effects of different anti–cancer drugs and the specificity to address dog mammary cancer is yet to be proven. Up until now, clinically adjuvant chemotherapeutics have been used due for the reason that specific anti–cancer drugs can cause a severe canine mammary malignancy. This might be due to hormonal involvement.

A homeopathic remedy that contains anti-oxidants such as C-Caps Formula can provided added support during the recovery phase of treatment. These types of remedies can help to strengthen the immune system and improve the overall physiology of the dog. If there is a decision not to treat the illness, a remedy could help to reduce the severity of symptoms and improve the overall quality of life.

Check with your veterinarian to see how this approach might complement the recommended treatment plan. Remedies are not a cure, but a helpful supportive therapy.