Sometimes, our pets eat things they shouldn’t, even when we think we’ve done everything possible to “pet proof” their environment. Strings, toys, bottle caps, and all manner of other items can be fair game for inquisitive pets; and if a pet cannot pass the ingested object on their own, medical removal will be necessary.
Recently, a wonderful and curious young canine patient decided to play with, and then swallow, a golf ball. He was presented to Anne Arundel Veterinary Emergency Center (AAVEC). This is type of case is not uncommon, as dogs often swallow balls and other foreign objects. These can often require surgical removal as the ball will often become lodged in the pylorus (the opening between the stomach and small intestine), leading to obstruction. Furthermore, sometimes the ball, or pieces, can become stuck in the esophagus.
In this case, attempts to induce vomiting did not help the pup expel the ball. As an alternative to surgical removal, video-endoscopy can be used for foreign body retrievals. The equipment is advanced and similar to the equipment used in human hospitals. Before this particular pet’s procedure, they were fasted overnight and anesthesia and endoscopy were then pursued the following morning.
For this pet, endoscopy went well. An Olympus 9 mm-diameter video-endoscopy system was used, along with ingenuity (using a baby bottle liner), to go into the stomach via the throat/esophagus and then to the stomach. In golf terms, this involved working to put the “ball into the “hole.” But for this situation, we had to bring the hole to the ball, then trap it in the liner, and bring it back up with the endoscope. This is often a tricky effort as the ball is slick and moves around while the stomach is contracting. Fortunately, the ball was successfully captured and removed, and the pup was able to recover uneventfully.
This made for a very interesting Saturday morning at AVIM&O, working closely with our colleagues at Anne Arundel Veterinary Emergency Center.
Mast cells are special blood cells that are normally involved in the body’s response to allergens and inflammation. When these cells mutate, they develop into a mast cell tumor. Mast cell tumors are commonly found on the skin, but other sites include the lymph nodes, spleen, liver, bone marrow, and intestines. Mast cell tumors are often raised, red, hairless masses that can wax and wane in size.
Mast cells contain substances within their granules (the most common ones are histamine and heparin) that can cause local inflammation (redness) and occasionally bleeding. Due to the effects of the granules, most patients will be started on anti-histamines and antacids for supportive care.
Any new lump or bump should be evaluated by your veterinarian. There are several breeds that are at a higher risk of developing mast cell tumors in their lifetime, including Boxers, Bulldogs, Pit Bulls, Pugs and Boston Terriers, but dogs of any breed can be diagnosed with a mast cell tumor.
A mast cell tumor is usually diagnosed by fine needle aspiration. This procedure entails inserting a needle into the mass and aspirating back some cells. The cells that are removed are put on a slide and sent out to the laboratory for the pathologist to review.
Mast cell tumors vary in behavior. Some are slow-growing and less aggressive, while others grow quickly and cause discomfort. Initial evaluation of a dog with a mast cell tumor usually involves additional diagnostics to determine the extent of disease (also known as staging the disease). The most common sites for metastasis are the draining lymph nodes, liver, spleen, and bone marrow.
Additional diagnostics include:
Bloodwork (complete blood count and chemistry panel)
Regional lymph node aspiration
Abdominal ultrasound to evaluate the liver, spleen and lymph nodes
Possible aspiration of the spleen
In some cases, we may also recommend a bone marrow aspirate. There are additional tests that can be done to try and predict the behavior of the mast cell tumor. This can include testing for a mutation, called c-kit, or performing a mast cell tumor panel.
Mast cell tumors are graded in two ways:
Patnaik scale: Tumors are graded I-III. Grade I tumors are the least aggressive, Grade II tumors are the most common, and Grade III tumors are the most aggressive.
Two Tier Scale: Tumors are graded high or low. Low-grade mast cell tumors are considered locally aggressive. High-grade mast cell tumors are not only locally aggressive, but are likely to spread to other areas of the body.
Treating Mast Cell Tumors
Treatment options for cutaneous mast cell tumors may include surgery, radiation therapy, chemotherapy and/or supportive care.
The gold standard of treatment is surgery to remove the mass. Mast cell tumors can be invasive and therefore, the surgeon will want to be aggressive by taking a large margin both around and under the tumor to try and ensure complete removal. Unfortunately, even when a large margin is taken, some of the tumor cells can still be left behind. When a mast cell tumor is not completely removed, there is a concern that there will be recurrence along the scar. If incomplete margins are found, then additional surgery or radiation therapy may be needed.
The goal of radiation is to try and clean up the residual disease that remains to slow the recurrence rate. Fortunately, radiation is very effective at preventing/slowing local mast cell tumor recurrence. Radiation therapy is administered while the patient is under anesthesia and consists of a daily treatment, Monday through Friday, for 3-4 weeks in a row. Studies indicate local control times of 2-5 years for patients treated with surgery and radiation.
Surgery and radiation therapy are local treatments that do not affect the spread of the tumor. Chemotherapy is beneficial for patients with a mast cell tumor that has already spread, is too large for surgery, or when there is a high risk for metastasis. Chemotherapy can be used with surgery or alone, but it is much more effective if the tumor has been removed.
Fortunately, chemotherapy is well-tolerated by most patients. Side effects may include stomach upset, a decreased white blood cell count, and possible thinning of the fur coat. Fewer than 10% of patients treated will experience significant side effects that warrant a visit to the animal hospital for outpatient care, and less than 1% will experience any life-threatening side effects or need to be hospitalized.
The prognosis for cutaneous mast cell tumors depends on the grade of the tumor, its location, whether or not it is positive for the kit mutation, and the presence of metastasis. Once a patient develops a mast cell tumor, they are at risk for developing others in the future. The majority of mast cell tumors can be successfully treated when found early.
The goal of any treatment option is to help maintain a good quality of life for your pet for as long as we can. Your oncologist will be able to discuss the treatment options available and what is best for your pet.
Our canine companions are just as likely to get cancer as humans are, and bladder cancer is one such type. The tumor that affects the bladder is known as transitional cell carcinoma, or urothelial carcinoma. It’s the most common tumor diagnosed in the bladder, and is diagnosed in roughly 80,000 dogs every year. The breeds affected most include Beagles, Scottish Terriers, Border Collies, and Shelties.
Common Clinical Signs
The most common signs indicating bladder cancer are:
Urine accidents in the house
Straining to urinate
Urinating more often
Blood in the urine
Urgency to urinate, but unable to produce much urine
Other health problems can cause these symptoms. However, with bladder cancer, the symptoms may be resolved for a short time with symptomatic therapy and then return not long after your pet has discontinued their treatment.
Diagnosing Bladder Cancer
CADET® BRAF – The first test we would choose for diagnosing transitional cell carcinoma (TCC) is the non-invasive CADET® BRAF test. ‘BRAF’ is the name for a gene that, in affected dogs, contains a single mutation indicating TCC. All we need to do is collect 30-40ml of your dog’s urine (over several days) and have it evaluated in a laboratory.
Cystoscopy – If the first option produces inconclusive results, we can try cystoscopy. A flexible scope is carefully inserted through the urethra and into the bladder while your pet is under anesthesia. We can then examine the urethra and bladder and take tissue samples for biopsy.
Urine cytology – Urine cytology is a third option where we can examine cells that have been shed into the urine. We can make a correct diagnosis with this test about 30% of the time.
Bladder Cancer Staging
Following a definitive diagnosis, we need to determine whether your pet’s cancer has spread into the lymph nodes, bones, and/or lungs. Therefore, before starting treatment, we need to perform:
Blood work and urine testing
An abdominal ultrasound to view the bladder, urethra, kidneys, regional lymph nodes, and abdominal cavity overall)
Chest X-rays and/or a CT scan to check for TCC within the lungs
A rectal exam to check for an enlarged prostate, lymph nodes, and urethra
Treatment Options for Pets
The goal of treatment is to slow cancer progression and improve your pet’s quality of life as much as possible. Available treatments include:
Piroxicam, an oral NSAID that decreases inflammation around tumors and helps to improve or resolve clinical signs. It has been found to have slowed tumor growth in approximately 18% of pets.
Chemotherapy, which can be used together with Piroxicam to treat TCC. Chemotherapy does not cause the same dramatic side effects in pets as it does in humans.
Radiation therapy is also a possible option and can be performed while your pet is under anesthesia.
We rarely recommend surgery due to its risks and the likelihood of cancer recurrence within a year of the procedure.