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Veterinary Teaching Hospital

The Pharmacokinetic of Capecitabine in Cancer-Bearing Dogs, Part 2

Purpose of Study

Canine malignant cancers are a devastating reality to many dog owners. Treatment options are often limited by pet behavior, owner finances and time commitments, and availability of veterinarians who can safely administer chemotherapy. Oral chemotherapy has become increasingly popular because it often costs less than injectable chemotherapy and can be given in the comfort of the patient’s home.

Capecitabine is a well-tolerated, oral chemotherapy drug used in humans for a wide variety of carcinomas including breast cancer, colorectal cancer and head and neck carcinomas. This chemotherapy drug has a short half-life in humans, allowing for quick dose adjustments if side effects are noted. During the first part of this study, we measured the levels of capecitabine in the blood after a single dose was given and looked at how well dogs tolerated the drug. All five enrolled dogs with advanced tumors tolerated capecitabine well and two had stable disease while on this chemotherapy drug.

The purpose of this second part of the study is to learn more about tumor response to capecitabine in a larger number of dogs. We hope that this study may provide support for the use of oral capecitabine chemotherapy in dogs with carcinomas.

Benefits

Once your dog is enrolled, this study covers the cost for 28 days of capecitabine, study-related oncology recheck examinations, and study-related lab work and imaging (if imaging is deemed necessary for tumor measurement). If your dog tolerates capecitabine well, you have the option of continuing this drug outside of the study, at your own expense, and under the supervision of your WSU Veterinary Oncologist.

It is possible that your dog’s carcinoma will not respond to treatment with capecitabine, however your dog’s participation in this study will help us explore which types of carcinomas are most responsive to this oral chemotherapy drug.

Enrollment Requirements

This study is being conducted dogs that have been diagnosed with a carcinoma. Dogs may be of any age, breed and gender. To be eligible for this study, dogs must have an appointment with the Oncology Service at the WSU Veterinary Teaching Hospital (WSU VTH) for confirmation/diagnosis of their disease and possible treatment. Dogs enrolled in this study must have a CBC and Serum Chemistry within 2 weeks of enrollment, more than 2,800 neutrophils, and no evidence of any other major disease that would result in a life expectancy of one week or less.

Treatment Methods

This study involves giving oral chemotherapy, on a set schedule, to your dog at home and 2-3 visits to the WSU Veterinary Teaching Hospital: the baseline day, rest-period blood work, and the final study day.

Baseline Day: Once enrolled in the study, if your dog does not have current blood work, blood will be drawn for a complete blood count (CBC) and serum chemistry. We will record measurements of your dog’s tumor, which may require imaging (X-ray, ultrasound, CT) and do a quick test to look at your dog’s eyes. Your dog will be sent home with 28 days of capecitabine, instructions, and a daily health log.

Capecitabine Administration Period: At home, you will give your dog capecitabine for 14 consecutive days. Days 15-21 you will NOT give capecitabine to your dog. During this period, we highly recommend that your dog has a CBC and examination. This can be done with your regular veterinarian or at the WSU VTH (if done at the VTH, the study will pay for associated charges). After the 7-day rest period, you will give your dog capecitabine for another 14 consecutive days.

Final Study Day: Within 3 days of the last dose of capecitabine, your dog will return to the WSU VTH for a physical exam, eye exam, recheck blood work and tumor measurement. After this appointment, your dog’s study enrollment will be completed.

Owner Responsibilities

Owners are responsible for bringing their dog to the WSU VTH for the oncology appointment. They are responsible for the costs associated with the diagnosis of their dog’s carcinoma. To be enrolled in this study, owners must be willing to follow instructions/safety protocols to give their dogs an oral chemotherapy drug at home, complete a daily log of their dog’s health while on the drug, and return to the WSU VTH for the final study day.

Contact Information

Valorie Wiss
Clinical Studies Coordinator
509-335-0798
v.wiss@wsu.edu

Three-legged happy dog outside in the grass.

Can surgery cure my pet of cancer?

Cancer is a scary diagnosis for any pet owner, but there are often surgical treatment options that can improve your pet’s quality of life and, in some cases, even eliminate the cancer.

Is my pet a candidate for cancer surgery?

Whether your pet is a candidate for surgery depends on numerous factors, including the location, type, and grade of the tumor.

The behavior of tumors varies significantly depending on the type. Some tend to grow very invasively, like a plant growing long roots in all directions. Others tend metastasize by spreading to distant places and organs.

An invasive tumor type is ideally removed with at least 1-inch margins in all directions. Sometimes that means surgery often entails amputation if the tumor is located on or near an extremity, such as a limb or a paw. A tumor on the head might require removal of parts of the jaw or an eye to achieve clean margins.

How are tumors diagnosed?

Tissue samples, or biopsies, are often used to diagnose the tumor by histopathological examination before surgery, and diagnostic imagining is a valuable tool in determining the location of tumors and if they are growing close to or even into important organs. X-rays, computerized tomography (CT) and magnetic resonance imaging (MRI) are frequently used.

From a biopsy, the tumor type can often be clarified and given a grade, or an estimation of the tumor’s aggressiveness.

There are several types of biopsies:

  • Incisional biopsy – One or several little pieces of the tissue are obtained for histopathological examination.
  • Excisional biopsy – The entire tumor is taken out for examination, without or with limited surgical margin. This is in general only done if the likelihood is high the tumor is benign or the tumor is very small. If the tumor turns out to be malignant with a high likelihood of cancer cell invasion beyond what was removed, it can be much more difficult to define the appropriate margins in a follow-up surgery.
  • After tumor type is diagnosed, these surgeries are considered based on how much margin the surgeon can remove:
  • Intracapsular resection (cyto-reductive surgery or debulking) – A portion of the tumor is removed but some visible tumor is left behind. This is in general done due to the presence of important, non-resectable organs close to the tumor. Radiation is usually recommended after or before an intracapsular resection.
  • Marginal resection – The tumor is removed without margin, leaving microscopic tumor behind. Additional treatment is usually necessary.
  • Wide resection – A margin of visibly normal tissue is resected together with the tumor to minimize the risk of leaving behind tumor cells. This is the most common type of surgery when surgery is used as the only treatment for cancer. Many cancer types of low or intermediate grade can be successfully removed this way. A wide resection often entails wound reconstruction to enable closure of the wound or to ensure normal function.
  • Radical resection – The entire structure the tumor is growing in is removed. This is commonly the case when amputation is an option, but it is difficult when located in areas other than extremities.

This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.

Golden retriever holding a cardboard sign in its mouth that reads, "I love my oncologist".

What is a canine osteosarcoma?

Osteosarcoma is the most common primary bone tumor in dogs, accounting for roughly 85% of tumors in the canine skeleton. They can be quite painful and can appear in any bone, although they are most frequent in front limbs and long bones, including the radius, ulna, humerus, femur, and tibia. Osteosarcomas appear to affect middle-aged to older large to giant breed dogs more commonly. The cause of this tumor is largely unknown.

What are some of the signs of osteosarcoma?

Lameness is the most common sign of osteosarcoma in dogs. Lameness may develop suddenly (after vigorous activity, for example) or slowly. Depending on the location of the tumor, a swelling or mass-like effect may be seen in the affected leg. Any lameness in a large-breed dog that does not promptly resolve with symptomatic therapy should be examined by a veterinarian.

Osteosarcoma is both a locally invasive tumor and a tumor with a high likelihood of metastasis, or spread, to other organs, most commonly the lung. Approximately 90-95% of dogs with osteosarcoma are considered to have metastasis at the time of their diagnosis, although metastasis will only be evident at the time of diagnosis in approximately 10% of dogs and in others the metastatic tumors are considered to be microscopic.

How is osteosarcoma diagnosed?

Radiographs, or X-rays, of the affected leg and the thorax are commonly used to determine the stage or extent of the cancer. Dogs with enlarged lymph nodes will also typically have the lymph nodes sampled for microscopic examination. Radiographs of affected legs are often highly suggestive of the diagnosis, and biopsies are not necessary for all dogs with compatible lesions on radiographs. Often, obtaining blood for a complete blood count and biochemical profile, and a urinalysis will be advised, as these can help assess overall health and provide information that potentially influences treatment recommendations. When aggressive therapy is being considered, a computed tomography, or CT, examination of the lungs will also be recommended to screen more precisely for metastasis.

How is osteosarcoma treated?

Amputation to remove the primary tumor, combined with chemotherapy to treat the metastatic disease, is the best treatment for preservation of quality (relief of pain) and quantity of life for dogs with the limb form of osteosarcoma.

Not every dog is a candidate for amputation and the decision to amputate is often difficult for owners. Dogs with severe arthritis in the unaffected limbs or weakness due to neurologic disease may not be candidates for amputation. Dogs can function on three legs much better than most owners think. Some institutions offer limb-sparing surgery, in conjunction with chemotherapy, but this can only be done when the tumor is in the radius or ulna near the carpal joint (wrist). Generally, chemotherapy treatment includes 5 doses completed over 3-4 weeks. Drugs commonly used include cisplaitn, carboplatin and doxorubicin. Amputation without chemotherapy can remove the source of pain but, generally, metastases will become apparent in 3-4 months. 

Palliative therapies are those aimed at keeping the leg more comfortable so the dog can live with it longer. Radiation therapy will improve comfort in approximately 70-80% of treated dogs. Generally, only a few large doses of radiation are administered. Administration of analgesics, which can be done in conjunction with palliative radiation therapy, can improve the level of comfort in some dogs.

Additionally, a class of drugs known as bis-phosphonates is being tried for dogs with osteosarcomas. These drugs inhibit bone resorption or break down. They have been used in the human field for osteoporosis and in the treatment of tumors that have metastasized to bone to relieve pain.

Dogs with osteosarcoma in other bone locations are often treated with a combination of surgery, radiation therapy, and chemotherapy.

What is the prognosis for dogs with osteosarcoma?

The prognosis for dogs undergoing surgery to remove the primary limb tumor (amputation or limb-sparing surgery) and treated with chemotherapy is fair to good. About half of dogs with osteosarcoma treated in this manner will be alive 1 year after diagnosis; approximately 25% of dogs treated in this fashion are alive 2 years after diagnosis, and occasional dogs will be cured. Dogs treated with either amputation or palliative radiation therapy live, on average, approximately 6 months before complication of the local tumor or metastatic disease cause death or prompt euthanasia.

Where can I get help if my dog has osteosarcoma?

Cancer of any kind is a diagnosis no pet owner wants to hear, but our board-certified veterinary oncologists can help you get an accurate diagnosis and develop a treatment plan. Call 509-335-0711 to schedule an appointment or visit our oncology webpage for more information.


This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.

Oncology cat patient

What is lymphoma?

Lymphoma, also known as a lymphosarcoma or LSA, is common in cats and is caused by a cancerous proliferation of lymphocytes, or white blood cells that normally function in the immune system. Any breed of cat can develop lymphoma.

What causes lymphoma in cats?

Feline leukemia virus (FeLV) at one time was a leading cause of lymphoma in cats and typically young cats were infected. Now that the incidence of FeLV has decreased, cats still develop lymphoma, but it is generally older cats and different forms. The feline immunodeficiency virus (FIV) has also been shown to increase the risk of a cat developing lymphoma six times over a non-infected cat.

The cause of the disease unrelated to FeLV or FIV is unknown, although environmental smoke exposure has been found to increase risk and a possible link to long-standing inflammatory disease has been theorized. 

What are some signs my cat has lymphoma?

Cats with lymphoma present with a variety of signs because lymphocytes can be found in nearly every organ in the body. Compared to other species, cats seem to have more forms of lymphoma in atypical locations or not in normal lymphoid tissues. Most species present with large lymph nodes, but this is a rare form in cats.

Young cats typically present for masses in the chest cavity and owners notice signs of difficulties breathing or vomiting of food. Older cats commonly develop the tumor in their intestines and owners may notice weight loss, diarrhea, or vomiting. Lymphoma can also develop in nasal passages, kidneys, spinal cord, liver, eyes, or a single lymph node, and the signs seen are more specific to the organ affected.

How is lymphoma diagnosed?

Lymphoma is often diagnosed with a biopsy, a minor surgical procedure to remove a piece of a lymph node or other organ that may be affected by cancer; thoracic and abdominal radiographs; ultrasound (to look for big nodes in the abdomen and to look at the liver and spleen); or bone marrow examination. Obtaining blood for a complete blood count and biochemical profile, testing for FeLV and FIV, and a urinalysis is always advised, as these can help assess overall health and provide information that potentially influences treatment recommendations. Special stains to determine if the lymphoma is of B-cell or T-cell origin are sometimes recommended.

How is lymphoma treated?

Chemotherapy should always be considered a critical part of the treatment for lymphoma. The best responses in terms of length of tumor control and survival are generally seen with the use of more than one chemotherapy drug, although there are approaches that involve a single drug. Chemotherapy drugs commonly used include doxorubicin, vincristine, cyclophosphamide, prednisone, and L-Aspariginase.

Some treatments are very aggressive and relatively short (six months in total) and others are less aggressive but extend for one to two years, depending on the results of testing.

Chemotherapy generally acts quickly and even cats with severe signs can have relief soon after starting therapy, sometimes as quickly as 24 hours. Surgery is occasionally recommended as a part of treatment, but this is usually either to reach a diagnosis or to remove a potentially life-threatening problem (for example intestinal rupture due to a tumor mass). Surgery is never curative and should always be followed by chemotherapy. Radiation can also play a role in the treatment of very localized lymphoma.

What is the prognosis for a cat with lymphoma?

Cats with lymphoma have unpredictable responses and survivals. Depending on the site of the tumor, mean survivals with chemotherapy range from 6-9 months. The problem is that this is only an average and most cats tend to do either much worse or much better. Young, FeLV negative cats with mediastinal lymphoma are quite regularly cured with chemotherapy, but cats with lymphoma in their central nervous system typically have a bad prognosis. Most other forms of lymphoma in cats have unpredictable outcomes. 

Lymphoma is one of the most chemotherapy-responsive tumors seen in veterinary medicine and cats can tolerate chemotherapy relatively well. Unfortunately, there few strong predictors of which cats will have good responses to chemotherapy and long survivals, and survival is therefore difficult to estimate at the outset. Starting treatment is often the only way to know how a cat will respond.

Lymphoma is viewed as a systemic disease since lymphocytes in their normal functioning travel throughout the body, meaning the cancer is also moving, though not metastasizing in a classical sense. Even if a tumor diagnosed as lymphoma has been surgically removed, the disease is not gone.

Where can I get help if my cat has lymphoma?

Cancer of any kind is a diagnosis no pet owner wants to hear, but our board-certified veterinary oncologists can help you get an accurate diagnosis and develop a treatment plan. Call 509-335-0711 to schedule an appointment or visit our oncology webpage for more information.


This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.

LINAC

What is radiation therapy?

Radiation therapy is a type of cancer treatment that uses beams of intense energy to kill cancer cells. The Washington State University Veterinary Teaching Hospital uses a linear accelerator, or LINAC, to accurately and safely direct radiation at tumors while protecting and limiting damage to surrounding healthy tissue. The teaching hospital is just one of a handful of veterinary hospitals in the Northwest with the technology.

Radiation therapy is frequently used to treat:

  • Mast cell tumors
  • Soft tissue sarcomas
  • Oral tumors – acanthomaous epulis, squamous cell carcinoma, fibrosarcoma, melanoma
  • Nasal tumors
  • Brain tumors

How is it different than chemotherapy?

Chemotherapy is a form of cancer treatment in which a patient is given drugs designed to kill cancer cells. It treats the entire body and is often used for tumors that metastasize or spread throughout the body. Radiation therapy, however, is target to a specific area of the body where the cancer exists.

How does radiation therapy work?

Radiation therapy works by the deposition of energy on or near DNA. Because the radiation damages DNA, cells die when they try to divide. Normal and cancerous cells are killed in the process.

Most animals being treated with radiation will undergo multiple rounds of radiation therapy with the goal of killing the maximum number of tumor cells while allowing time for repair and repopulation to occur in the normal cells. Animals are anesthetized prior to treatments.

Cancer cells are not all that different from normal cells. Their cell cycle and means of growth and division are the same as normal cells, but they have just lost their controls. The more aggressive the cancer, the more “out of control” the cells behave.

When a tumor is very small and essentially undetectable, it is a very metabolically active population of cells. Once the tumor becomes visible, it is already starting to slow down in its growth, and once it becomes a very large mass, it is actually a very slow growing, metabolically inactive population. Radiation acts primarily on rapidly dividing cell populations, so tumors should be treated when they are as small as possible.

What are some potential side effects?

Despite the best attempts at sparing normal tissues, there are side effects to radiation therapy. These can generally be divided into early and late effects.

Early effects happen within 3 months post-therapy, are expected, and will get better. They include hair loss, irritation of the skin caused, mucositis, and conjunctivits. Symptomatic therapy (and patience) is generally the best treatment and care must be taken not to damage the tissues further (animal scratching or human scrubbing). Acute edema will occur on rare occasions after radiation of nervous tissue and must be treated with high doses of corticosteroids until the symptoms resolve.

Late effects occur months to years after radiation and will not get better. Acceptable side effects include alopecia (hair loss) and hyperpigmentation of the skin and cataracts. Less acceptable effects would be nervous tissue atrophy or necrosis, bone necrosis, and skin fibrosis. These are serious side effects that may mean the treatment itself was done improperly.

If my pet has cancer, where can I go for more help?

Cancer of any kind is a diagnosis no pet owner wants to hear, but our board-certified veterinary oncologists can help you get an accurate diagnosis and develop a treatment plan. Call 509-335-0711 to schedule an appointment or visit our oncology webpage for more information.


This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.

Oncology Patient

What is lymphoma?

Lymphoma, also known as a lymphosarcoma or LSA, is caused by a cancerous proliferation of lymphocytes, or white blood cells that normally function in the immune system. It is one of the most common tumors seen in dogs. It affects dogs of any breed and age, although most are middle-aged or older when diagnosed. Golden retrievers are considered a breed at increased risk of developing a lymphosarcoma. The cause of these tumors is not known.

What are some of the signs my dog has lymphoma?

The most common form of lymphoma causes a non-painful enlargement of one or more lymph nodes that can be seen or felt on the surface of the body. Occasionally, a lymph node becomes large enough to impair function (obstruction of blood flow or airway, for example).

Other forms can involve the liver, spleen, bone marrow, gastrointestinal tract, skin, nervous system, and other organs. The clinical signs will reflect the organ system involved. For instance, dogs with gastrointestinal forms may vomit or have diarrhea. Many dogs will simply feel ill, lose their appetite, or become lethargic.

In some cases, the tumor is an incidental finding when an otherwise healthy appearing dog is seen by a veterinarian for an unrelated reason.

If you notice fast growing lumps on your dog that seem to be in the area of the major joints (at the neck, in front of the shoulders, in the armpits, at the back of the knees or in the groin) have it examined by a veterinarian, even if the animal feels well.

How is lymphoma diagnosed?

Lymphoma is often diagnosed with a biopsy, a minor surgical procedure to remove a piece of a lymph node or other organ that may be affected by cancer. Since lymphoma can spread to almost any tissue in the body, a thorough work-up needs to be done to determine the stage of disease.

Staging can involve aspiration of one or more lymph nodes, thoracic and abdominal radiographs, ultrasound (to look for big nodes in the abdomen and to look at the liver and spleen), or bone marrow examination. Often, obtaining blood for a complete blood count and biochemical profile, and a urinalysis will be advised, as these can help assess overall health and provide information that potentially influences treatment recommendations.

Lymphoma is categorized into five stages, depending on the extent of the disease in the body:

  • Stage I – single lymph node enlarged 
  • Stage II – multiple nodes enlarged on either the front half or back half of the body 
  • Stage III – multiple nodes enlarged on both front and back halves of body 
  • Stage IV – involvement of the liver and/or spleen 
  • Stage V – bone marrow involvement, or involvement of other organs (e.g. gastrointestinal, skin, nervous system) 

Each numbered stage can be further divided into two substages:

  • Substage A – patient feels well
  • Substage B – patient is ill

How is lymphoma treated?

Lymphoma is often treated with chemotherapy drugs. Lymphosarcoma are among the most chemotherapy-responsive tumors seen in veterinary medicine, and most dogs tolerate chemotherapy well with minimal impact on their quality of life.

The best responses in terms of length of tumor control and survival are generally seen with the administration of more than one chemotherapy drug, although there are approaches that involve administration of a single drug. Chemotherapy drugs commonly used include doxorubicin, vincristine, cyclophosphamide, prednisone, and L-Aspariginase. In some dogs with localized disease, surgery or radiation therapy can also play a role in treatment.

What is the prognosis for a dog with lymphoma?

The prognosis for dogs with lymphoma is highly variable and depends on the clinical stage. Dogs in lower stages of the disease and that feel well will do better with treatment than dogs that are ill and have more advanced disease.

Lymphoma is not generally viewed as curable in dogs, although some will experience what seems to be a cure with appropriate treatment. A dog can start with one stage of the disease and progress over time to another (usually more advanced) stage.

Most dogs treated with chemotherapy will experience a remission, a period in which there is no detectable cancer, and the dog feels well. Remission times are variable, but most dogs with the lymph node forms of lymphoma will have initial remissions lasting in the range of 6-9 months before evidence of the tumor is seen again; second remissions can be achieved in many of these dogs, but any subsequent remission is expected to be shorter in duration than the first.

Survival times for most dogs treated with combination chemotherapy protocols are in the range of approximately 1 year.

Where can I get help if my dog has lymphoma?

Cancer of any kind is a diagnosis no pet owner wants to hear, but our board-certified veterinary oncologists can help you get an accurate diagnosis and develop a treatment plan. Call 509-335-0711 to schedule an appointment or visit our oncology webpage for more information.


This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.

Yellow Lab

It is normal for your dog to get a few lumps and bumps on its body as he or she gets older. Most of these lumps are harmless – or benign – but they could also be the sign of something more serious, like a mast cell tumor.

What is a mast cell?

Mast cells are a type of white blood cell that play an important role in the immune system. Most are found in the skin and areas that come in contact with the outside environment. They contain chemicals like histamine, which is released during allergic reactions and certain immune responses. 

What is a mast cell tumor?


A mast cell tumor is a tumor consisting of mast cells. They are common in dogs, accounting for approximately 20% of all skin tumors. In addition to forming in nodules or masses in or on the skin, they can also affect regional lymph nodes, the spleen, liver, intestine, bone marrow, and other areas of the body. For most dogs, the underlying cause promoting the development of the tumor is not known

What are the signs of a mast cell tumor?

These tumors can form on any skin site on the body and with varying appearances. Most develop as solitary lumps or masses in or underneath the skin, but occasionally dogs will have multiple masses. Some are slow growing and cause little irritation, while others can be ulcerated, angry lesions that spread rapidly. Some dogs may have signs of systemic disease – disease affecting other parts of the body – which can be caused by some of the biologically active compounds found within mast cells.

How are mast cell tumors diagnosed?

Veterinary oncologists recommend collecting cells from skin lumps before removal to rule out the growth as a mast cell (or other malignant) tumor. Veterinarians can easily identify mast cells by examination of a fine-needle aspirate of the suspect mass.

To determine the extent of the tumor, your veterinarian may collect cells from regional lymph nodes and bone marrow for microscopic examination, in addition to performing imaging of the thorax and abdomen. A complete blood count, biochemical profile, and urinalysis can help assess overall health and in forming treatment recommendations.

A grading scale is used to describe the aggressiveness of mast cell tumors, with grade I the least aggressive and least likely to spread to other organs (metastasize). Most grade II tumors do not to metastasize, although they can. Grade III tumors are highly aggressive and likely to metastasize.

How are mast cell tumors treated?


While most mast cell tumors are considered locally invasive and can be difficult to completely remove, surgical removal is still the most recommended treatment. Wide areas of surrounding tissue that appear to be normal also need to be removed to increase the likelihood that the tumor is completely removed. For cases in which the tumor was not able to be completely removed, radiation therapy is often recommended, although a more aggressive second surgery is possible for some dogs. Chemotherapy is used as a treatment, but it is usually reserved for dogs with grade III tumors. Some dogs will also be treated with medications to fight the secondary effects of the tumor.

What is the prognosis for dogs with mast cell tumors?


If tumors are caught when small, surgical removal is usually adequate. Mast cell tumors, though, can be unpredictable, and even grade I and II tumors can be difficult to control and aggressive in terms of metastasizing.

The prognosis for completely removed grade I and grade II tumors, however, is excellent. The prognosis for incompletely removed grade I and II tumors treated with radiation therapy after surgery is also excellent, with approximately 90-95% of dogs having no recurrence of tumor within 3 years of radiation therapy. The prognosis for dogs with grade III tumors is considered guarded, as local recurrence is likely.

What should I do if my dog has a lump?

If you are concerned about a growth on your dog, schedule an appointment with your veterinarian or our community practice veterinarians by calling 509-335-0711.


This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your pet incurred by following these descriptions or procedures.

Nina Nechyporuk did not give it much thought when her senior ragdoll cat, Abby, jumped from her lap to the floor and made a short wheezing sound.

Dr. Janean Fidel, veterinary oncologist, and Margaret Wong, a fourth-year student, examine Abby prior to her undergoing a second round of chemotherapy.

Strange, but nothing to worry about, she thought. Just two days later, though, Abby was noticeably struggling to breathe, and by Friday, her owners, Nechyporuk and Richard Waugh, were unsure if their beloved cat would survive.

“We didn’t think she was going to make it through the night — it was unbearable,” Nechyporuk says.

In the ensuing days, the couple would learn Abby had a life-threatening tumor in her trachea. While just millimeters in size, it was blocking her airway.

There was never any doubt they would do everything possible to save Abby, but when the treatments available at veterinary clinics near their home outside of Vancouver, Canada, failed to keep the cancer at bay, options were dwindling.

The best hope was some seven-and-a-half hours away in Pullman at Washington State University’s Veterinary Teaching Hospital.

Not a typical ragdoll


Nechyporuk and Waugh have always considered themselves a “cat family,” but until Abby, all their cats had been strays and others in need of love. As they considered their first purebred in 2003, a ragdoll sounded like the perfect fit — the breed, after all, is known for being overly affectionate and for its tendency to go limp and relaxed when picked up

It did not take long for the couple to realize that Abby did not fit the breed description.

“As a young cat, she didn’t really have much use for Richard and I,” Nechyporuk says. “She was a very independent cat and standoffish. She does not behave at all like you would expect from a ragdoll.”

That never detracted from their love of Abby.

She’s a fighter


Waugh first arrived in Pullman with Abby in Memorial Day of 2019 prepared for an extended stay. Under the care of Dr. Janean Fidel, WSU’s lead veterinary oncologist, Abby was to undergo 18 rounds of radiation therapy using the teaching hospital’s  linear accelerator, or LINAC, a machine that allows tumors to be targeted with powerful radiation.

Abby responded remarkably well to the treatments, and nearly a month later she and Waugh finally returned home. A follow-up CT scan in October of 2019 showed the treatments had worked and the tumor had shrunk.

“They asked us to come back in the spring of 2020, in March or April,” Nechyporuk says. “But we all know what happened — COVID. We did not make it back for that appointment.”

Then, in November, the wheezing started again. The tumor had returned, and Abby found herself back at WSU. Dr. Fidel recommended 10 doses of radiation therapy to target the tumor, followed by several rounds of chemotherapy. Abby has completed her radiation treatment and has had two chemotherapy treatments, the second of which was delayed due to her having a low white blood cell count.

Despite having undergone 28 radiation treatments since May of 2019, a recent X-ray of Abby’s lungs shows they are still in good condition.

“We have so much confidence in Dr. Fidel. We wouldn’t have Abby treated anywhere else,” Waugh says. “The outlook for Abby is good. She is not suffering, she’s not in pain and she responds very well to the treatment — she’s a fighter.”

Dr. Fidel says it is unlikely Abby would be alive if it were not for the radiation treatments she received using the LINAC. The machine is one of the only available for radiation treatment in the region. Every year it is used to treat hundreds of animals throughout Washington, Idaho, Oregon, Montana, and Canada.

The WSU Veterinary Teaching Hospital is currently raising money to purchase a new LINAC. As the machine has aged, it is no longer as dependable as it once was, as demonstrated by the two times during Abby’s treatments that it unexpectedly stopped working. Fortunately, it only resulted in slight delays for Abby.

“It is like a very old car that keeps needing to be repaired,” Dr. Fidel says. “It is repairable, and it functions, but it is going to flat out stop at some point.”

Fidel says a newer machine will also allow radiation to be better directed at tumors while protecting surrounding healthy tissue, and dosage rates can be better moderated, reducing treatment time.

Love

Abby, her owners say, has changed considerably since starting her treatment. The once independent cat now seems to enjoy the companionship of Nechyporuk and Waugh. She is genuinely affectionate, and she has even become more of a lap cat.

“She sits on my lap every single night — now I am the center of her world,” Nechyporuk says. “We love her to bits.”

“I think,” Waugh adds, “she realizes how much we love her.”