What is Breast Cancer Awareness Month?
October is breast cancer awareness month! It is a time to raise awareness about the causes of and treatments for breast cancer. Although it is usually referred to with humans, breast cancer can occur in any mammal, including your dog or cat. Early detection and treatment of breast cancer is key in treating it, so hopefully the following article provides you with some more insight into identification and prevention methods!
Causes of Breast Cancer in Pets
The development of breast cancer in pets can be caused by a variety of factors, many of them still unknown. Exposure to certain hormones, such as progesterone, however, can increase the risk of breast cancer in pets. There is also a higher incidence of this illness in specific breeds, such as Chihuahuas, Boxer dogs, poodles, Yorkshire terriers, dachshunds, etc. More research is still needed to confirm the effect of gene mutation and environmental factors on mammary tumor development, but human cancer studies suggest that there may be a link between animal genes and tumor growth. Surgical removal is the best option for small tumors, and an ovariohysterectomy may be recommended for multiple tumors or chains or mammary chains. If the tumor is larger or is spreading to other parts of the body, the veterinarian may also propose chemotherapy treatment.
Heat Cycles and Mammary Tumors in Dogs
The most distinguishable sign of a dog’s heat cycle is the 14-21 day bloody vaginal discharge. There are four estrous cycles to heat: proestrus, estrus, diestrus, and anestrus. During this period, progesterone levels increase, causing the female to become breeding-receptive. Once completed, progesterone levels will decrease again, and the process will repeat in another 5-11 months.
By not spaying your dog, or removing your pet’s ovaries, their risk of breast cancer could be substantially higher. The hormones that are responsible for mammary gland tumors, such as progesterone, can be reduced by ovary removal, therefore reducing the risk of breast cancer. Evidence has shown that dogs who have been spayed before their first heat have a 0.5% chance of developing cancer. If they have not undergone surgical removal by the second heat, the percentage rises to 8% after the first, and 26% after the second.
Breast Tissue, Mammary Glands, and Cancer Development in Cats
Similar to dogs, breast cancer is usually attributed to abnormally high hormone levels that can uncontrollably increase the proliferation of cells in the breast tissue. Sexually intact cats have a seven times higher risk for mammary tumors compared to spayed cats, so getting your pet spayed early is most definitely recommended! Cats spayed before six months of age have only a 9% percent risk of developing mammary tumors, whereas the risk increases to 14% in cats spayed between seven and 12 months. Like with humans and other mammals, the risk is higher for females and less so for males. The most common clinical sign of a mammary tumor is the occurrence of palpable masses underneath the abdomen. If you see this, contact a veterinary immediately.