Finding a lump on your dog or cat can understandably raise concerns, especially when it appears near the mammary glands. Mammary tumors are abnormal growths that develop in mammary tissue, and they can be benign or malignant. While these tumors are more commonly associated with female pets, males can also develop them. Because you cannot determine whether a lump is cancerous simply by looking at it, veterinary evaluation is important. Learning more about the signs, diagnosis, and treatment of mammary cancer can help you make informed decisions about your pet’s care.
Understanding Mammary Tumors
Dogs and cats have multiple mammary glands located along the underside of the body. A tumor may develop in one gland or affect multiple areas along the mammary chain. Some mammary tumors are benign, meaning they do not invade nearby tissues or spread to distant parts of the body, while malignant tumors can behave more aggressively.
Mammary tumors can vary considerably in size, texture, and appearance. Changes involving the skin over the mass, such as irritation or ulceration, can sometimes occur as well.
Signs That Deserve Veterinary Attention
Regularly handling and grooming your pet may help you notice physical changes sooner. Contact your veterinarian if you discover a new lump or a change involving the mammary area. Signs that may warrant an examination include:
- A firm lump or swelling near a mammary gland
- Multiple lumps along the abdomen or chest
- Changes in the size or shape of an existing mass
- Redness, irritation, discharge, or ulceration around a growth
- Discomfort when the area is touched
These changes do not automatically mean your pet has cancer. Other conditions can cause lumps or changes in mammary tissue, so a veterinary examination is needed to determine what may be happening.
How Mammary Cancer Is Diagnosed
Your veterinarian will typically begin with a physical examination and review of your pet’s medical history. Depending on the findings, additional diagnostic testing may be recommended. Tests can help your veterinarian evaluate the mass and look for evidence that disease has affected other areas.
A definitive diagnosis often depends on examining tumor tissue under a microscope, which may occur after a biopsy or surgical removal. Your veterinarian may also recommend blood tests or imaging, such as chest x-rays or abdominal ultrasound, based on your pet’s individual situation. These findings can help guide treatment planning and provide more information about the tumor.
Treatment & Ongoing Care
Surgery is commonly used to treat mammary tumors when removal is appropriate. The extent of surgery can depend on factors such as the tumor’s size, location, number, and suspected behavior. Laboratory examination of the removed tissue can provide important details about the tumor type and whether it has features associated with more aggressive disease.
Some pets may need additional evaluation or treatment after surgery. Depending on the diagnosis and stage of disease, your veterinarian may discuss referral to a veterinary oncologist or other therapies. Follow-up visits are also important for monitoring healing and checking for new or recurring changes.
Taking the Next Step for Your Pet
Early veterinary attention can provide more information about a mammary lump and help you understand the available options. If you notice a new mass, avoid waiting for it to become painful or significantly larger before scheduling an examination. Your veterinarian can evaluate the area, recommend appropriate testing, and explain what the findings mean for your pet.
Keeping up with routine veterinary examinations also gives your care team opportunities to identify changes you may not have noticed at home. By staying attentive to your pet’s body and seeking veterinary guidance when something changes, you can play an active role in protecting their health and comfort.