Skin Cancers in Dogs

There are many forms of benign and malignant skin cancer in dogs. While many are common, there are rare forms that pet owners may not recognize. Most cancers affect older dogs, but there are cases where puppies have developed a cancerous growth. Check your dog's skin regularly for changes. If you notice anything unusual, contact your veterinarian. Seeking treatment as early as possible leads to the best odds for a full recovery.

  1. Adenocarcinoma

    • Adenocarcinoma is a cancer in the sweat glands. Small, red bumps appear on the skin, usually around the face, and may bleed. A veterinarian will take a biopsy of the bump and will check the lymph nodes to see if the cancer has spread. Radiation and chemotherapy are the common treatments.

    Epidermotropic Lymphoma

    • Epidermotropic lymphoma, also called cutaneous T-cell lymphoma, is a rare cancer that starts in the lymphocyte cells. Symptoms include loss of hair; loss of skin pigmentation; skin ulcers and lesions; and itchy, scaly, red skin patches. Your veterinarian will take a sample of the dog's skin for biopsy. There is no cure, but surgery, chemotherapy and radiation prolong the dog's life.

    Hemangiosarcoma

    • Hemangiosarcoma is a skin cancer that starts in the blood cells. The tumors are dark blue or red patches on the skin that are often mistaken for bruises. This form of cancer occurs in less than 25 percent of all cancer cases. Boxers, German shepherds, golden retrievers and pit bulls have the highest risk for developing this cancer. A skin biopsy confirms the diagnosis. If the tumor is not invasive, surgery removes the entire growth and prognosis is good. If the tumor has spread to other tissue, the average survival span is less than a year.

    Malignant Melanoma

    • Malignant melanoma is a common form of skin cancer in dogs. The cancer develops in the pigment cells. The tumors appear as dark, raised growths on the skin, mouth and nails. It is an aggressive cancer that needs immediate treatment. A veterinarian will perform a biopsy and check the lymph nodes for cancerous cells. Surgical removal of the tumor is best. The more tissue that's removed, the better the dog's survival time. After surgery, most dogs only survive for a year. Radiation is only used if surgery is not an option.

    Mast Cell Tumor

    • Mast cells come from the bone marrow and live in the tissue near blood vessels and nerves. The cells help repair tissue and build new blood vessels. Most cases of mast cell cancer develop after a dog's eighth birthday. Look for a growth that suddenly appears or increases in size. Half of all mast cell tumors appear on the trunk and around the anus, vulva or scrotum. The masses may seem to shrink or become red and itchy. A veterinarian will take a biopsy and determine the stage of the cancer through X-rays or a biopsy of the lymph nodes. Stage 1 has a good prognosis, but Stage 4 means the cancer has spread to other organs. Treatment depends on the stage. Catching the cancer in Stage 1 provides better odds for survival.

    Melanocytic Tumors

    • Melanocytic tumors develop in the skin cells that produce skin pigmentation. There are benign and malignant growths. The cancer is more prevalent in older dogs and certain breeds and genders. Male boxers, spaniels and terriers are more likely to develop this form of tumor. The tumors develop as large masses on the face, feet, scrotum and trunk. They often grow rapidly. Left untreated, the cancer spreads to the lymph nodes. A veterinarian performs a biopsy to diagnose the cancer and determine if it is benign or malignant. Surgical removal of the tumor is best. If the cancer spreads to other tissue, chemotherapy is usually recommended.

    Mucocutaneous Plasmacytoma

    • Mucocutaneous plasmacytoma starts in the white blood cells. The cancer develops as small bumps on the legs and trunk, but can develop along the mouth and ears. The bumps may bleed. When caught early, surgical removal is best. If the cancer spreads to surrounding tissue, radiation is recommended. The prognosis for this skin cancer is good, especially when caught early.

    Squamous Cell Carcinoma

    • Squamous cell carcinomas take two forms. There is a link between sun exposure and squamous cell carcinoma. Cutaneous squamous cell carcinomas appear in older dogs, particularly those with short hair. Lesions look like warts. They appear on the belly, head, legs and around the anus. Subungual squamous carcinomas are most common in older, short-hair breeds. You'll see these growths on the toes or under the claws. Surgical removal of the tumor is necessary. The tumors spread fast, so urgent treatment is the best way to prolong a dog's life.