What Is a Hard Tumor in a Cat?

Finding a hard tumor on a cat can be unnerving, even frightening. Such tumors can be as small as a pea or as large as your fist, and they may feel close to the skin or may be very deep underneath the skin. It is impossible to diagnose a tumor based on size or texture alone, so you should consult your veterinarian immediately if you find a hard mass on your cat. Many tumors are benign, and some cancerous tumors are highly treatable.

  1. Cysts

    • Technically speaking, all tumors are cysts, but many people use the term cyst to refer to a benign growth. Hard cysts are common in cats and can be caused by infection, abnormal tissue growth or the development of fat deposits. Because a cyst may indicate an infection, it's important to talk to your veterinarian if you discover a cyst. Your vet may prescribe antibiotics to treat infection. If the cyst is a benign growth, your veterinarian will advise watchful waiting. Check the cyst regularly to ensure it has not grown and is not causing your cat any discomfort.

    Benign Tumors

    • A cutaneous mast cell tumor is a common benign tumor in cats over the age of 4. They typically manifest as small nodules that feel like they are just under the skin, and do not have hair growing on them. Histiocytic tumors are another variety of mast cell tumors that may appear in several locations on the body. While these tumors are benign, veterinarians typically recommend removal because they can grow and interfere with movement and overall health.

    Pre-Cancerous Tumors

    • Precancerous tumors are tumors that are currently benign but that may later develop into cancer if the cells within the tumors begin developing out of control. Basal cell tumors are one of the most common varieties of these tumors; they are common in older cats. They can be located on any area of the body and are typically pigmented. Basal cell tumors on the head, neck or legs are more likely to become cancerous than basal cell growths in other locations. Your veterinarian may remove such a tumor or advise watchful waiting.

    Malignant Tumors

    • Cancer of some organs may first manifest as hard masses. Swollen, very hard lymph nodes around the neck and groin may also indicate cancer and can be so large that they feel like tumors. Some forms of skin cancer are associated with tumors. If you notice hyperpigmentation and growths on your cat's sin with a tumor nearby, consult your veterinarian immediately.