Ring Around a Tumor: How Tiny Chemo Beads May Treat Your Pet’s Cancer

Often, when a veterinary surgeon removes a tumor, it’s followed up with chemotherapy and/or radiation. But there’s a new option that might protect your pet from a recurrence of the tumor, with fewer side effects and at a lower cost.

“After removing certain types of tumor surgically, we can implant a circle of tiny beads impregnated with a chemotherapy drug called cisplatin around the edges of the tumor,” said board-certified veterinary surgeon Dr. Phil Zeltzman. “These beads slowly release the drug and are then reabsorbed by the body.”

One of the major advantages of chemo beads is when they’re compared to the use of cisplatin in chemotherapy given intravenously (IV), which is the usual practice.

“Cisplatin given IV can cause severe kidney damage in dogs,” Dr. Zeltzman said. “But the beads administer a very small fraction of the dose you’d give IV, and greatly reduce that risk.” In fact, he said, the beads don’t seem to cause any of the general side effects common to IV chemotherapy, although they can cause local side effects such as skin irritation, swelling, and drainage.

The beads should ideally be implanted at the time the tumor is removed, because that’s when the margins are most obvious. Additionally, implanting the beads later in the course of the pet’s treatment, such as when a biopsy is back, means a second surgery under general anesthesia, with its associated risks and cost.

How effective are the beads? While they can stop the tumor from coming back, they do not protect against metastases. And they’re not the right choice for every kind of tumor, nor every patient. Dr. Zeltzman says he’s seen the best results in tumors such as anal gland carcinomas, soft tissue carcinomas, and thyroid tumors, among others.

One success story was Conan, a 9-year-old Lab with anal gland cancer. After Dr. Zeltzman removed the tumor and implanted the beads, Conan had a fast recovery and was soon back loving life – and the water!

“I call this a success story even though Conan did eventually pass away from cancer,” he said. “But he had an excellent quality of life, running, swimming and playing after his surgery. He passed away peacefully, surrounded by his family members, seven and a half months after his surgery. He was a very special dog, and I know his family treasured the many good months they had together.”


One big negative of the beads: You’ll need to wear gloves if you’re going to clean or touch any drainage from the incision area. Additionally, your dog will need to be kept away from other dogs and in a plastic cone that prevents chewing the area until it’s healed.

Additionally, because they’re still not in wide use, be sure to discuss chemo beads with the veterinary surgeon well in advance of surgery, to give her time to obtain them before your pet’s tumor is removed.

Are chemo beads right for your pet? Talk to a veterinary surgeon and find out!


Fibrosarcoma in Dogs (Nasal and Paranasal Sinus)

Overview of Fibrosarcoma of the Nasal and Paranasal Sinus

Nasal and paranasal sinus fibrosarcomas are slow growing, progressive, invasive tumors of the nose, nasal cavity and surrounding communicating recesses that can occur in dogs.

As with other tumors, the cause is unknown. These tumors are seen more commonly in dogs than cats and are seen in all ages, although it is most common in middle aged and older animals. Fibrosarcoma of the nasal and paranasal sinus are seen more commonly in the male and there is no breed predilection.

What to Watch For

Signs of nasal and paranasal sinus fibrosarcoma in dogs may include: 

  • Nasal discharge
  • Epistaxis (bleeding from the nose)
  • Epiphora (tearing from the eyes)
  • Sneezing
  • Halitosis (bad breath)
  • Anorexia
  • Facial deformity
  • Exophthalmia (bulging eye)
  • Seizures (secondary to aggressive tumors invading the brain)
  • Diagnosis of Nasal and Paranasal Sinus Fibrosarcoma

  • Complete blood cell count (CBC)
  • Biochemical profile
  • Urinalysis
  • Chest X-rays
  • Skull/nasal X-rays
  • Computed tomography imaging (CT scan) or magnetic resonance imaging (MRI)
  • Nasal bacterial culture
  • Rhinoscopy (scoping the nasal cavity) and biopsy
  • Rhinotomy (cutting into the nasal cavity) and biopsy
  • Biopsy is necessary for a definitive diagnosis
  • Treatment of Nasal and Paranasal Sinus Fibrosarcoma

  • Surgery in combination with radiation therapy
  • Radiation therapy
  • Chemotherapy
  • Antibiotic therapy may be helpful in controlling secondary infection
  • Anti-inflammatory drugs may help as temporary symptomatic therapy if more aggressive treatment is not pursued.
  • Home Care and Prevention

    Administer all medication and follow recommendations by your veterinarian. Follow up as directed. If your pet’s condition is not improving and/or getting worse, seek veterinary attention at once.

    Overall, nasal and paranasal fibrosarcomas are very aggressive, and carry a guarded prognosis.

    There is no preventative care for fibrosarcoma.

    Gastrointestinal (GI) Neoplasia in Dogs

    Overview of Canine Gastrointestinal Cancer

    Gastrointestinal neoplasia is cancer located anywhere throughout the gastrointestinal (GI) tract, including the oral cavity (mouth), esophagus, stomach, small intestines, large intestines and rectum. GI cancer can be primary, which means it originates in the GI tract, or metastatic, which is spread from another site.

    No specific causes of primary cancer have been identified, although it has been associated with several disorders. Chronic inflammation or irritation has been thought to be a contributing factor in some cases. Spirocerca lupi, a parasite of the esophagus, may cause associated cancer.

    Cancer usually occurs in middle-aged to older dogs. Depending on the tumor type and location, different breeds, ages, and species can be affected. The Belgian shepherd and Scottish terrier have a higher incidence of gastric carcinoma than other breeds. Collies are also more likely to develop malignant intestinal cancer.

    What to Watch For

    With gastrointestinal cancer, clinical signs are largely dependent on the location of the cancer, size of the mass, and to a degree, the specific type of cancer. General signs to watch for by location include:

  • Oral. Watch for halitosis (bad breath), bleeding from the mouth, difficulty eating and drooling.
  • Esophageal. Watch for regurgitation, excessive salivation and weight loss.
  • Gastric (stomach). Watch for vomiting (with or without blood), weight loss, inappetence and black tarry feces.
  • Small intestinal. Watch for diarrhea, vomiting, weight loss, anorexia, black, tarry feces and gas.
  • Colonic (large intestinal). Watch for diarrhea (with mucus or blood) and straining to defecate.
  • Rectal. Watch for straining and blood in stool.
  • Diagnosis of Gastrointestinal Neoplasia in Dogs

    Your veterinarian may recommend the following diagnostic tests:

  • Baseline tests to include a complete blood count (CBC), biochemical profile and urinalysis
  • Fecal examination
  • Abdominal radiographs (x-rays)
  • Thoracic (chest) radiographs
  • Abdominal ultrasound
  • Upper gastrointestinal contrast radiography (dye study)
  • Endoscopy of the upper and/or lower bowel and biopsy
  • Abdominal exploratory and biopsy
  • Treatment of Gastrointestinal Neoplasia in Dogs

  • Hospitalization and support as needed, such as fluid therapy or blood transfusions
  • Surgical resection (removal), which is the treatment of choice
  • Surgical debulking (removing as much as possible) to help improve clinical signs
  • Chemotherapy
  • Radiation therapy
  • Dietary manipulation
  • Home Care

    Administer medication and diet as directed by your veterinarian. Return for follow-up as directed by your veterinarian. If your pet has a recurrence of signs, contact your veterinarian at once.

    Prognosis varies depending on the location, size, type and ability to remove the tumor surgically.

    There is no known specific prevention of gastrointestinal cancer. Treat all underlying inflammatory disorders in their early stages if possible.

    In-depth Information on Gastrointestinal Neoplasia in Dogs

    Gastrointestinal (GI) neoplasia (cancer) occurs infrequently in dogs as compared to neoplasia involving other systems. Over two-thirds of GI neoplasms in dogs are malignant – they are aggressive, and often spread locally or to other areas. The most common types of gastrointestinal tumors include adenocarcinoma, lymphoma, leiomyosarcoma, leiomyoma, squamous cell carcinoma, fibrosarcoma, plasmacytoma, and mast cell tumors. In general, older animals are affected most commonly.

    The cause of GI neoplasia is rarely evident, and signs can be extremely variable from patient to patient as signs usually reflect the size, location, and type of tumor. Some patients may be relatively asymptomatic, while others may be in immediate need of intensive support and hospitalization, to include intravenous fluid therapy and blood transfusions. There are many diseases/disorders that cause similar clinical signs to patients with gastrointestinal neoplasia.

    Esophageal Neoplasia

    Esophageal cancer is the least common site for tumors in the GI tract. The most common tumors associated with the esophagus include squamous cell carcinoma, fibrosarcoma, and sarcoma (associated with the parasite Spirocerca lupi).

    Megaesophagus, which is a distended and/or poorly functional esophagus, and as the clinical signs seen with this condition (regurgitation, excessive salivation, and difficulty eating/swallowing) often mimic esophageal neoplasia, it needs to be considered and differentiated.

    There are many diseases associated with megaesophagus:

  • Intrathoracic masses/growths may put pressure on the esophagus from the outside, creating a blockage
  • Vascular ring anomaly is an entrapment of the esophagus within several structures, causing a partial megaesophagus
  • Neuromuscular diseases (nerve and muscle) including myasthenia gravis, polymyositis, systemic lupus erythematosus, polyradiculoneuritis, botulism, tetanus and dysautonomia
  • Central nervous system diseases including infectious, inflammatory, neoplastic (cancerous) and traumatic disorders
  • Miscellaneous disorders including endocrine diseases (hypothyroidism, hypoadrenocorticism), certain toxicities (lead, thallium, acetycholinesterase), and thymomas, which are tumors arising from an organ in the chest
  • Esophagitis is the inflammation of the esophagus and needs to be differentiated
  • Esophageal foreign body is an object within the esophagus and have symptoms similar to esophageal neoplasia
  • Esophageal stricture is an abnormal narrowing of the esophagus and should be ruled out
  • Esophageal diverticula are pouch-like dilatations of the esophageal wall and should be ruled out
  • Esophageal fistula is an abnormal communication between the esophagus and another structure
  • Hiatal hernia is an abnormality of the diaphragm allowing part of the stomach to be displaced into the chest cavity and needs to be ruled out
  • Metastatic Neoplasia (Cancer) in Dogs

    Understanding Metastatic Cancer in Dogs

    Metastatic neoplasia, commonly referred to as “mets”, is cancer that has spread from its original site to other sites in the body. The lungs and local lymph nodes are common sites of metastasis for many tumor types, but metastases can occur in almost any organ and are associated with malignant tumors.

    Metastasis occurs by spread of cancer cells either through the bloodstream, or via the lymphatic system (an important part of the immune system). The impact on your pet will depend on where the primary tumor is located, and where the metastases are located.

    What to Watch For

    Signs of metastatic neoplasia in dogs may include: 

  • Weakness
  • Coughing
  • Weight loss
  • Loss of appetite
  • Changes in water consumption
  • Difficulty breathing
  • Vomiting
  • Diarrhea
  • Constipation
  • Lameness
  • Lumps on or under the skin
  • Abnormal behavior
  • Diagnosis o Metastatic Neoplasia in Dogs

    The diagnosis of metastatic disease depends on finding a primary tumor as well as evidence of spread of the tumor to other sites within the body. The work-up will vary with the tumor type. Tests which may commonly be performed in dogs include:

  • History and physical exam
  • Complete blood count (CBC)
  • Biochemical profile
  • Urinalysis
  • Abdominal ultrasound
  • Fine needle aspirate of masses or enlarged lymph nodes
  • Biopsy
  • Radiographs (x-rays). Radiographs of the chest will sometimes show evidence of metastatic disease, even before the primary tumor has been discovered.
  • Treatment of Metastatic Neoplasia in Dogs

    Chemotherapy and/or surgery are often helpful in slowing down progression of cancer. Unfortunately, when there is already evidence of metastatic disease at the time of diagnosis, the prognosis is grave and response to chemotherapy may be poor.

    Supportive care may consist of supplemental nutrition, fluid therapy, treatment of secondary infections, and pain medication.

    Home Care and Prevention

    Give all medications as directed by your veterinarian. Monitor your dog for increasing lethargy, weight loss, respiratory difficulties, anorexia and worsening of the original clinical signs of illness.

    Early recognition and treatment of cancer may reduce the risk of developing metastatic disease. Signs of illness that don’t resolve within a few days, weight loss, and new lumps on your dog should be brought to the attention of your veterinarian as early as possible.

    Hemangiosarcoma of the Bone in Dogs

    Overview of Canine Bone Hemangiosarcoma

    Hemangiosarcoma is a type of cancer that arises from blood vessels and can occur almost anywhere in the body in dogs. It is a highly metastatic form of cancer, meaning it spreads readily to other tissues. Usually when hemangiosarcoma occurs in bone it is due to metastasis from another site, although rarely, it may actually arise in the bone; the bone is then referred to as the primary site.

    This tumor affects the bone much more rarely than osteosarcoma, but when it occurs in bone it can sometimes be very difficult to distinguish from the osteosarcoma. The cause of hemangiosarcoma is largely unknown. In people this type of cancer has been linked to exposure to vinyl chloride, a chemical agent.

    Hemangiosarcoma occurs most commonly in middle-aged to older, large breed dogs. It can affect the axial skeleton, which includes the bones of the spine, pelvis and skull, as well as the appendicular skeleton, which includes the arms and legs.

    This is a lethal form of cancer in your pet. Average survival rate in animals with this type of cancer, even with treatment, is only months. In most cases, the tumor has already spread widely or will spread widely throughout the body, despite therapy and will continue to grow. When it primarily affects the bone, it can cause lameness and general debilitation of your pet during its development and progression.

    What to Watch For

    Signs of hemangiosarcoma of the bone in dogs may include: 

  • Lameness or pain, especially in the legs
  • Unexplained swelling of any bone
  • Broken bones without severe trauma
  • Bleeding

    Diagnosis of Hemangiosarcoma of the Bone in Dogs

    Diagnostic tests are necessary to diagnose the tumor and define the extent of disease. Tests that your veterinarian may wish to perform include:

  • Complete medical history and physical exam
  • Radiographs (X-rays) of the affected body part
  • Radiographs of the chest/lungs
  • Abdominal (belly) radiographs
  • Abdominal ultrasound
  • Cardiac (heart) ultrasound
  • Complete blood cell count (CBC)
  • Biochemistry profile
  • Urinalysis
  • Biopsy of the tumor

    Treatment of Hemangiosarcoma of the Bone in Dogs

    Treatment may include the following:

  • Surgical removal of the tumor, which usually involves removing the affected bone
  • Pain medications
  • Chemotherapy
  • Radiation therapy as an alternate form of palliative treatment for pain relief in very select cases
  • Home Care and Prevention

    Your veterinarian will most likely prescribe pain medication to ensure your pet’s comfort. These medications may be given prior to definitive diagnosis and/or after surgery. Medication will usually be in the form of pills or narcotic pain patches that are placed on the skin to release a constant level of medication across the skin.

    You should limit your dog’s activity to minimize pain and to prevent what is called a pathologic fracture, which is an abnormal breaking of the bone due to the cancer weakening the bone. Your pet should not run, jump or play during this time. You should watch your dog carefully and give assistance when he climbs stairs or when he gets in and out of the car.

    Have your veterinarian evaluate promptly any unexplained bump or lameness that develops. Lameness is more likely to be associated with arthritis or injury to ligaments and tendons than cancer, but it is worth having your dog evaluated nonetheless.

    If your dog does not improve with rest or anti-inflammatory drugs, radiographs of the affected part of the body may be indicated to exclude bone cancer as a cause of the lameness or pain.

    Hemangiosarcoma, like other cancers, is not currently preventable.

    In-depth Information on Hemangiosarcoma of the Bone in Dogs

    Hemangiosarcoma is a type of cancer that most commonly affects the spleen, liver and heart and typically causes bleeding from the ruptured tumor. Although it can arise in bone initially, this is rare. Most often when it occurs in bone, the tumor has spread there from another site in the body. Thus, if your dog is diagnosed with bone hemangiosarcoma it is vitally important that other more common sites of this tumor are excluded as the primary site.

    As with most forms of cancer, very little is known about what causes hemangiosarcoma to develop. It is a highly lethal form of cancer and thus the diagnosis and treatment should be prompt and aggressive.

    Related Symptoms or Diseases

  • Lameness. This is a general term used to describe pain or discomfort experienced when your pet moves normally or exercises minimally. Although your dog may develop lameness due to arthritis, ligament or tendon tears, or cartilage injury, lameness is also a cardinal sign of bone tumors. Therefore, any unexplained or chronic lameness in your pet warrants further investigation.
  • Pathologic fractures. If your dog experiences a fracture with minimal trauma, a pathologic fracture should be considered. Although fractures are most often a result of trauma, they can also occur in bones that have been weakened by cancer. Evaluating an X-ray may lead to the suspicion that the bone is abnormal; however, definite diagnosis of a tumor requires a biopsy. Pathologic fractures will not heal if fixed using standard techniques
  • Osteomyelitis. This is an infection in the bone and an uncommon condition that occurs as a result of infectious organisms such as bacteria or fungi getting into a bone. These organisms most commonly gain entrance to the bone through an open wound, open fracture or rarely through the blood (a blood borne infection). The appearance of osteomyelitis may be similar to some bone cancers because it often appears as a proliferative or fuzzy mass-like lesion on an X-ray. Differentiating these types of infection from bone cancer typically requires that a biopsy and a culture be performed.        
  • Bone infarction. This is a very rare condition in which a blood clot blocks the blood supply to a bone, resulting in death of the bone. On an X-ray this appears as a lytic lesion, which means there is loss of bone, and is similar to the appearance of bone cancer.
  • Metastatic tumors to bone. Occasionally a bone cancer can be due to the metastasis or spread of cancer from a primary cancer elsewhere, most commonly mammary gland cancer. These types of cancers tend to have a distinctively different appearance on X-rays than primary bone tumors. Although their radiographic appearance may alert your veterinarian to their presence, a biopsy is still required for a definitive diagnosis. It is important to distinguish tumors that have spread from other tissues to bone from those that arise in bone initially because the treatment differs. For metastatic tumors an attempt is made to determine the site of the primary cancer. If your pet is diagnosed with cancer, your veterinarian may wish to consult with an oncologist or cancer specialist to understand the specific behavior and treatment of the cancer.
  • Lipoma (Fatty Tumor) in Dogs

    Overview of Lipoma (Fatty Tumor) in Dogs

    A lipoma is a benign fatty tumor usually composed of mature fat cells. They are usually soft, well defined, and subcutaneous (under the skin). Lipomas are variable in size and shape and may occur anywhere, although they are commonly found on the ventral (under) surfaces of the chest and abdomen.

    All dog breeds may be affected, but they are most common in older dogs, especially older female dogs. Lipomas are very common in dogs, and less common in cats.

    Infiltrative lipomas are those that develop in deeper tissue and between muscle layers. These lipomas tend to be firmer and more broad-based than typical lipomas. These tumors also grow slowly, but are more invasive and less well defined. They grow by expanding into the tissue and may cause pain. Infiltrative lipomas are much less common than typical lipomas.

    What to Watch For

    Signs of fatty tumors in dogs may include: 

  • Skin swellings
  • Lumps and bumps
  • Usually they are spherical or oval in shape
  • Diagnosis of Lipomas in Dogs

    Your veterinarian may recommend the following diagnostic tests:

  • Fine needle aspirate. This easy diagnostic test involves placing a needle attached to a syringe into the mass and withdrawing a sample of cells. The contents of the needle and syringe are expelled onto a glass slide for analysis.
  • Cytology. The slides are evaluated microscopically for evidence of adipose (fat) cells.
  • Biopsy. If there is no conclusive evidence on aspiration, a biopsy (tissue sample) may be taken. If the mass is small, an excisional biopsy, which is a biopsy where the entire mass is removed, may be done. Biopsies usually require sedation with local anesthesia or general anesthesia.
  • Treatment of Lipomas in Dogs

    If a lipoma is small and slow growing, your veterinarian may advise an owner to observe the mass for any changes. If there are no significant changes, treatment is not necessary. In other cases, the following treatments are available:

  • Excision (removal) of a lipoma should be considered if it is growing rapidly, causing discomfort, or it interfering with the mobility or life style of the animal.
  • Infiltrative lipomas should be aggressively treated with a wide surgical excision. Most of the times, excision will be incomplete, as some of the tumor cells will remain on the body. If the remaining tumor is slow to return, this may be all the treatment needed.
  • Radiation therapy is available if the lipoma is invasive and cannot be completely removed.
  • If surgery is required to remove a lipoma, preoperative blood work (complete blood count and profile) are generally recommended.
  • Home Care

    Note any changes in previously diagnosed lipomas that are not being treated. Significant changes should be re-evaluated.

    After a lipoma has been removed, watch the incision for any swelling, redness or discharge. Make sure your pet is not licking or chewing at the incision line. Sutures are generally removed in 7 to 10 days.

    There is no way to prevent the occurrence of lipomas. Once lipomas are noted, they should be closely monitored. Lipomas should not be allowed to become so large that they are difficult to remove or they interfere with function.

    Infiltrative lipomas may need more aggressive treatment.

    What is Cancer in Dogs?

    Cancer, also known by the medical term neoplasia, is a transformation of normal cells into abnormal malignant cells, and it can take many forms. Some types of cancer in dogs involve solid masses, or tumors, while others involve the blood or bone marrow in leukemia. Cancer can develop in virtually any organ or body system.

    In addition, some cancers spread or metastasize to other areas of the body. They can spread to nearby tissues, or invade the blood stream or lymphatic system. Cancer commonly metastasizes to the lung. The exact symptoms, treatment and prognosis vary with the specific tumor type and situation.

    For more information about a specific type of cancer, click on the related articles or use the search engine.

    Malignant Melanoma in Dogs

    Overview of Malignant Melanoma in Dogs

    Malignant melanoma is a tumor arising from melanocytes, which are the cells that produce pigment. Although there is no known cause of malignant melanoma, the predisposition of many dog breeds makes many researches believe there is a genetic predisposition for this disease.

    Malignant melanoma can originate from different areas in the body, most often the oral cavity, skin, and digits. The aggressiveness of the tumor and the likelihood of the metastasis vary with the tumor location. Any organ may be affected by a metastatic melanoma (tumor that has spread from a primary site).

    Melanoma is more commonly in dogs than cats and primarily affects middle-aged to older pets (often 9 to 12 years). Black dogs may be predisposed. Male dogs are more commonly affected.

    The Scottish terrier, Boston terrier, Airedale terrier, cocker spaniel, boxer, springer spaniel, Irish setter, Irish terrier, chow chow, Chihuahua, and Doberman pinscher are the most common breeds affected by melanomas of the skin and toes. The poodle, dachshund, Scottish terrier and golden retriever are the most common breeds affected by melanomas located in the mouth. Other breeds affected include the giant schnauzer and miniature schnauzer, Golden retriever, and Gordon setter.

    What to Watch For

    Tumors occur most commonly in the skin, digits and in the mouth. The tumors may be pigmented (black) or un-pigmented.

    In patients with cutaneous melanoma:

  • Solitary (single) growths that may or may not be pigmented or dark in color, most commonly on the face, truck, feet, and scrotum in dogs

    In patients with the oral form:

  • Halitosis (bad breath)
  • Bleeding from the mouth
  • Drooling
  • Facial swelling
  • Difficulty eating

    Patients with advanced disease may experience difficulty breathing due to metastasis (spread) to the lungs.

  • Diagnosis of Malignant Melanoma in Dogs

  • A complete blood cell count (CBC), biochemical profile, and urinalysis should be performed in all cases, and are most often within normal limits.
  • Screening chest X-rays, although often within normal limits, may be of benefit in older patients, and/or may reveal evidence of pulmonary (lung) metastasis.
  • Fine needles aspirates retrieve cells for analysis with a small needle and syringe and may be helpful in diagnosing malignant melanoma.
  • Evaluation of the associated lymph nodes by fine needle aspirate/cytology is recommended as well.
  • Abdominal ultrasound may be indicated in patients with lesions that occur in or on the hind legs.
  • Biopsy of the mass is necessary for a definitive diagnosis of malignant melanoma.
  • Additional tests to help determine the type of tumor or the overall malignancy. Tests may include immunohistochemical staining may confirm the type of tumor or evaluation of the mitotic index may help determine the malignancy associated with that particular tumor.
  • Treatment of Malignant Melanoma in Dogs

  • Treatment of choice is surgical removal of the tumor. Wide surgical margins are recommended. Melanoma involving the nail bed or digit often requires amputation of the digit. Melanoma involving the oral cavity often necessitates radical mandibulectomy, or removal of the a part of the associated lower jaw, or maxillectomy, which is the removal of the part of the associated upper jaw.
  • Adjunctive (concurrent) chemotherapy is recommended if surgical excision is incomplete or the mass cannot be removed surgically.
  • Radiation therapy may of benefit in certain cases.
  • Chemotherapy is often indicated in addition to surgery and/or radiotherapy due to the aggressiveness of the tumors and the high rate of metastasis. Commonly used drugs include carboplatin or cisplatin
  • A new vaccine, called Canine Melanoma Vaccine DNA by Merial, has been given a conditional license for the treatment of stage II or stage III oral melanomas in dogs. The vaccine works by injecting a protein into the body that alerts the body’s immune system to the presence of the melanoma tumor protein tyrosinase. Use of the vaccine has shown very promising results so far by increasing survival times. Research is ongoing and there are several studies under development. The vaccine is recommended every 2 weeks for 4 doses and a booster vaccine at six-month intervals.
  • Immunotherapy to regulate the immune system may be of benefit in selected cases.
  • Home Care and Prevention

    Prognosis is generally guarded and early detection is very important. Twenty to fifty percent of cutaneous melanomas in dogs are malignant. Those occurring in the scrotum, digit, or oral cavity are most often malignant. Aggressive and radical surgery greatly increases survival times and decreases reoccurrence rates.

    Contact your veterinarian if there is recurrence of the melanoma or change at the surgical site. Return for follow up as directed by your veterinarian.

    There is no preventative care for malignant melanoma.

    Uterine Tumors in Dogs

    Overview of Canine Uterine Tumors 

    Uterine tumors are cancers that arise from the uterus. They are rare in dogs and are most commonly benign, but may also be malignant. Uterine tumors, by definition, only occur in intact female dogs. They are usually seen in middle aged to older dogs.

    What to Watch For

    Signs of uterine tumors in dogs may include:

  • Vaginal discharge
  • Abdominal distension
  • Anorexia (lack of appetite)
  • Constipation
  • Vomiting
  • Weight loss
  • Lethargy
  • Straining to urinate
  • Frequent urination
  • Diagnosis of Uterine Tumors in Dogs

  • Complete history and physical exam
  • Complete blood count (CBC)
  • Biochemical profile
  • Urine analysis
  • Chest radiographs (x-rays)
  • Abdominal radiographs or ultrasound exam
  • Mass biopsy
  • Treatment of Uterine Tumors in Dogs

    Ovariohysterectomy or spay is the treatment of choice. Chemotherapy may be recommended in selected cases.

    Home Care and Prevention

    Monitor for recurrence of original clinical signs and spay your female dogs.

    In-depth Information on Uterine Tumors in Dogs

    Many dogs with uterine tumors have no clinical signs of illness. This is because most tumors are benign and therefore do not spread to other organs. The most common tumor types are leiomyomas (fibroids) and fibromas. Malignant tumors are often adenocarcinomas or leiomyosarcomas. Large tumors may cause compression of other abdominal organs and may result in constipation, vomiting, or frequent urination. Abdominal distension is sometimes noted due to large tumor size or development of fluid in the abdomen secondary to the tumor.

    In many cases, the tumor may be present concurrently with an infection in the uterus, called pyometra. Dogs with pyometra are commonly lethargic, excessively thirsty, anorexic, vomiting and often have vaginal discharge. Licking of the vulva is common in animals with vaginal discharge, which may prevent observation of the discharge itself. Other conditions may cause similar clinical signs to those seen in animals with uterine tumors. These include:

  • Vaginitis or vaginal tumors. Infection or tumors of the lower reproductive tract may cause discharge and licking as well.
  • Tumors of other abdominal organs. Masses associated with the liver, spleen, or gastrointestinal tract may also cause abdominal distension and possible fluid accumulation in the abdomen.
  • Liver/kidney/gastrointestinal/metabolic diseases. Many diseases can cause general lethargy, anorexia and vomiting. These are not signs specific to one organ system, but should prompt a visit to the veterinarian for appropriate evaluation.

    In-depth information on Diagnosis

    A complete history and physical exam are crucial. A thorough history is always important in establishing a list of possible diagnoses. A physical exam may reveal an enlarged uterus, or vaginal discharge that had gone unnoticed previously in some dogs. Additional tests may include:

  • Complete blood count. A CBC evaluates the red and white blood cells as well as the platelets. The results may be normal in a pet with a uterine tumor, but an elevated white blood cell count may be seen with both tumors and infections of the uterus.
  • A biochemical profile evaluates blood sugar, blood proteins and electrolytes, as well as providing information about liver and kidney function. This is useful to get an overall idea of systemic health and may guide further diagnostic testing.
  • Urine analysis. Evaluation of the urine is part of a complete laboratory assessment and gives a better indication of kidney function than the biochemical profile alone.
  • Abdominal x-rays or abdominal ultrasound exam. Imaging studies of the abdomen will allow visualization of the uterus. A normal uterus is hard to see on x-rays, so a prominent uterus is often a sign of uterine pathology. An abdominal ultrasound is useful to differentiate a fluid filled uterus from a uterine tumor.
  • Chest radiographs. X-rays of the chest are a good idea to look for evidence of spread of cancer to the lungs. Although most uterine tumors are benign, the malignant types are aggressive tumors and may quickly spread to other organs, including the lungs. It is important to know if there is evidence of metastatic disease (spread of cancer from the primary site) prior to treating the pet.
  • Mass biopsy. Biopsy of a uterine tumor involves obtaining tissue for microscopic analysis. This enables the veterinarian to determine if the tumor is benign or malignant. The best way to obtain a tissue sample for biopsy is generally to remove the entire uterus and the ovaries.
  • In-depth Information on Therapy

    Surgery is the treatment of choice for dogs with uterine tumors. It is not clear how hormones may influence growth of uterine tumors, so it is advisable to remove not only the uterus, but the ovaries as well. Surgery therefore serves not only as a diagnostic modality, but as a therapeutic one as well.

  • If the tumor is benign, surgery should be curative.
  • If the tumor is malignant, chemotherapy may be recommended in addition to surgery. The purpose of chemotherapy is to prevent spread of malignant cells to other organs. Unfortunately, the efficacy of chemotherapy for malignant uterine tumors is not well known.
  • In cases of pyometra in addition to the presence of a tumor, antibiotics are indicated to treat the infection.
  • Renal (Kidney) Lymphosarcoma in Dogs

    Overview of Lymphosarcoma of the Canine Kidney 

    Lymphosarcoma is a general term for malignant cancers of lymphoid tissues, which may affect multiple organs, including the kidneys. Lymphosarcoma is a very common type of cancer in both dogs and cats, but the form affecting the kidney is much more common in cats than dogs.

    Lymphosarcoma is caused by cancerous lymphocytes, a type of white blood cell. Middle aged to older dogs and cats are affected.

    Lymphosarcoma is ultimately a fatal disease, but it often goes into remission with appropriate therapy. Many animals with renal lymphosarcoma often develop renal failure.

    What to Watch For

    Signs of lymphosarcoma of the kidney in dogs may include: 

  • Weight loss
  • Vomiting
  • Diarrhea
  • Poor appetite
  • Increased thirst and urination
  • Abdominal enlargement
  • Lethargy

    Animals with multi-organ involvement may show other signs of illness such as behavior changes, lack of coordination, especially of the hind legs in cats, extreme hind limb weakness, and yellow discoloration of the skin (jaundice).

  • Diagnosis of Renal Lymphosarcoma in Dogs

  • History and physical exam. The most common physical exam finding in dogs is enlargement of both kidneys. This will often be appreciable by abdominal palpation.
  • Complete blood count. A CBC evaluates the red and white blood cells, as well as the platelets. Affected patients may be anemic (low red blood cell count), and may have evidence of abnormal white blood cells in circulation, as well as platelet abnormalities.
  • Biochemical profile. This is important to evaluate kidney function and other organ function. It may help indicate which organs are involved in the disease process.
  • Urinalysis. Analysis of the urine provides further information with respect to kidney function.
  • Chest and abdominal x-rays. Imaging studies of the body cavities allows identification of the extent of cancer involvement and provides objective determination of kidney size.
  • Abdominal ultrasound. This is a non-invasive method to obtain more information regarding kidney architecture. It also allows examination of abdominal lymph nodes, which are often enlarged in cases of lymphosarcoma.
  • Fine needle renal aspirate or kidney biopsy. Lymphosarcoma may usually be diagnosed by a fine needle aspirate of affected kidneys, in which fluid is withdrawn by a needle. This is a relatively non-invasive procedure, which can be done with minimal or no sedation. If the aspirate sample is non-diagnostic, a tissue biopsy of the kidney will need to be performed.
  • Bone marrow aspirate. Obtaining a sample of the bone marrow is necessary if lymphosarcoma is suspected, as it allows determination of the presence of tumor cells in the bone marrow. This is part of what is called the staging process of the diagnostic work-up.
  • Treatment of Renal Lymphosarcoma in Dogs

  • The treatment of choice for lymphosarcoma is chemotherapy. This type of cancer is quite responsive to chemotherapy drugs.
  • Chemotherapy involves weekly visits to your veterinarian and often requires treatment by a veterinary internist or oncologist.
  • Home Care and Prevention

    Give all medications as prescribed by your veterinarian. Some chemotherapy drugs are given orally, at home. Monitoring for response to therapy as well as side effects from the chemotherapy is important. Vomiting, diarrhea, inappetence, and lethargy are signs to watch for at home.

    There are no measures to be taken to prevent development of renal lymphosarcoma.