At Your Service: Onoclogy

Oncology Service
Providing Families More Quality Time with their Companion Pets

Who We Are
The Harrington Oncology Program at the Tufts Foster Hospital for Small Animals at Cummings School of Veterinary Medicine provides state-of-the-art diagnostic, medical, radiation therapy and surgical techniques. Led by board-certified specialists in medical and radiation oncology, it is supported by a team of residents, dedicated technicians and staff.

Foster Hospital believes in a team approach to care and our oncologists work closely with a highly skilled surgery service with expertise in surgical oncology, as well as with the pathology, diagnostic imaging, interventional radiology and pain management services. Our collaboration allows us to offer treatment options that are customized based on the tumor type, the spread of the cancer, and the overall health of the pet. This could involve a single treatment modality or a combination of different therapies. In some cases, in accordance with the client’s wishes, a more conservative strategy may focus on palliative care. Through all of this we provide you and your client with detail on the type of cancer, treatment options, and expected outcomes, keeping quality of life as a top priority. The oncology service takes pride in ensuring that all of the client’s questions are answered and that the veterinarians, technicians and pet owners work as a team.

As an academic veterinary medical center, we are training the veterinarians of the future, and are also actively engaged in research into the causes, biology and treatment of cancer. As a member of the National Cancer Institute’s Comparative Oncology Trials Consortium, and through independent studies and collaboration with other veterinary and biomedical institutions, the oncology service is able to offer investigational therapies, in addition to conventional treatment. In addition, we participate in the Tufts Human Animal Cancer Collaborative with the Medical School at Tufts University, where treating cancer in companion animals helps inform how we treat humans.

Technology and Services Available
The Harrington Oncology Program is recognized nationally in the field, boasting some of the most advanced technology available in veterinary medical establishments. With medical staff and technicians well-versed and experienced in chemotherapy administration, radiation therapy and anesthesia, specific features of our service include:

  • Intravenous, intralesional an intracavitary chemotherapy administration, including long continuous-rate infusions
  • Melanoma vaccine administration
  • Siemens Primus linear accelerator with 6MV photon and 6-21 MeV electron capabilities and a 56-leaf collimator that allows for intensity modulated radiation therapy
  • Three-dimensional computerized radiation therapy planning
  • Strontium plesiotherapy
  • Various biospy techniques, including manual incision, punch, needle-core biopsies as well as image-guided (ultrasound or computed tomography) and open surgical procedures
  • Interventional radiologic procedures, such as chemoembolization and intra-arterial chemotherapy administration
  • Access to investigational clinical protocols

Referring a Patient
The Harrington Oncology Program typically sees new patients who have a confirmed cancer diagnosis. This often allows us to provide clients with a full array of staging and treatment options during the initial visit. We understand, however, that circumstances arise in which an oncology consult is valuable before a diagnosis is made. You should feel free to call us about these cases to facilitate a referral. We welcome the opportunity to even provide you with a telephone consult (free of charge) regarding general information on cancer management or to discuss a possible referral.

In situations when pet owners are uncertain whether they wish to pursue treatment for their pets with a cancer diagnosis, we encourage referrals to address their questions regarding anticipated course of the disease, treatment options and palliative care. You may contact Kelly Reed, our clinical liaison, at 508-887-4682, and she will facilitate all care for pets you refer.

Meet the Team

Radiation Oncology Faculty

Michele Keyerleber, DVM, DACVR, a board-certified veterinary radiation oncologist and faculty member, is a 2008 graduate of Cornell University’s College of Veterinary Medicine. She later completed a small animal internship at The Ohio State University, before returning to Cornell for a residency in radiation oncology. Dr. Keyerleber joined the faculty of Cummings School of Veterinary Medicine at Tufts University in 2011. Her research interests include radiation therapy planning for neoplasia in dogs and cats, brain tumors, and palliative radiation therapy. Dr. Keyerleber also has a strong interest in pain and side effect management for radiation therapy patients.

Elizabeth McNiel, DVM, PhD, DACVIM, DACVR is board-certified in radiation and medical oncology. She is a 1992 graduate of Texas A&M University and completed a small animal rotating internship at Angell Memorial Animal Hospital in Boston. Dr. McNiel completed a medical oncology residency program followed by a combined radiation oncology residency and PhD program at Colorado State University. Prior to coming to Cummings School of Veterinary Medicine at Tufts University in 2012, she served on the faculty of the University of Minnesota and Michigan State University. An active researcher, Dr. McNiel studies the molecular biology of canine and feline tumors in her laboratory at the Molecular Oncology Research Institute at the Tufts Medical Center. Her goal is to translate basic discoveries in the laboratory into clinical advances for animals through clinical trials.

Medical Oncology Faculty

Lisa Barber, DVM, DACVIM, is a 1992 graduate of Ohio State University. She completed a small animal internship and residency in veterinary oncology at the University of Pennsylvania School of Veterinary Medicine where she subsequently served as a staff oncologist prior to joining the faculty at Cummings School of Veterinary Medicine at Tufts University. She specializes in treating dogs and cats with a variety of cancers, and consults on large animals as well as exotic animals. Her research interests include epidemiologic studies to identify risk factors for various cancers as well as investigation of novel treatments for cancer.

Kristine Burgess, DVM, DACVIM, is a board-certified veterinary oncologist at the Tufts Foster Hospital for Small Animals at Cummings School of Veterinary Medicine. After receiving her undergraduate degree from UMass, and completing a masters degree from work at Dana-Farber Cancer Institute, Kristine went on to earn her DVM from the Cummings School in 1997. She subsequently completed her residency training at the University of Wisconsin. She collaborates with several other institutions to run clinical trials for new and advanced cancer treatments for dogs and cats, which may lead to better treatment options for both pets and humans.

Oncology Residents

Kelly Kezer, DVM, a first-year medical oncology resident, received her veterinary degree from Massey University in New Zealand. After graduation, she completed a small animal rotating internship at BluePearl Veterinary Partners in Tampa, Florida, a high-volume practice, where she solidified her interest in oncology. Dr. Kezer enjoys all aspects of veterinary oncology, but has particular interest in novel therapies and international veterinary medicine.

Felicia Lew, DVM, a second-year medical oncology resident, is originally from Seattle, Washington. A 2012 graduate of Washington State University College of Veterinary Medicine, she completed a small animal rotating internship at a private specialty hospital in San Diego, California. Dr. Lew has an interest in basic science research, specifically in cancer biology and carcinogenesis.

Bobbi McQuown, DVM, a third year oncology resident, is originally from the Midwest. Prior to veterinary school, she spent 5 years in the Army as a communications officer. In 2011, she graduated from the North Carolina State University College of Veterinary Medicine, subsequently completing a small animal rotating internship at VCA VREC/Shoreline in Connecticut. Her ongoing research includes assessment of palliative radiation therapy and anal sac tumors, IGF-1 levels in dogs with lymphoma, and the use of Palladia in dogs with heart base tumors.

Oncology Technicians
Amy Bengtson
Tiffany DeNitti
Jenn Ford
Pam Shaw

Clinical Trials Coordinator
Diane Welsh

Oncology Liaison
Kelly Reed

Clinical Case Challenge

Oscar, a 10-year-old male castrated Yorkshire terrier, presented to the Tufts Foster Hospital for Small Animals at Cummings School Radiation Oncology Service for a several month history of nasal signs. Oscar’s owners initially noted increased sneezing and increased respiratory noise/congestion approximately six months prior that was non-responsive to treatment with steroids and antibiotics. Intermittent unilateral epistaxis was then noted approximately three months prior. This progressed to a mild but noticeable facial deformity approximately three weeks prior to presentation.

On presentation to Foster Hospital for Small Animals, physical examination revealed a mild facial deformity over the dorsal maxilla. There was no evidence of nasal, ocular, or aural discharge but no airflow was present from the left nare. Nuclear sclerosis was present bilaterally and retropulsion of both eyes was normal. Mild dental calculus was present. The mandibular lymph nodes were mildly enlarged but soft and symmetrical. Thoracic auscultation and abdominal palpitation were unremarkable.

Based on examination findings, what are your primary differential diagnoses? What further diagnostics would you consider, and what treatment options would you recommend?

Diagnosis
Based on the clinical history of epistaxis and presence of facial deformity, neoplasia is the primary differential diagnosis. Adenocarcinoma is the most common nasal tumor in dogs. Additional neoplastic considerations include undifferentiated carcinomas, squamous cell carcinoma, fibrosarcoma, chondrosarcoma, osteosarcoma, and lymphoma. Non-neoplastic differentials are considered less likely, but include fungal infection (aspergillosis most common), other infectious rhinitis, or foreign body.

Figure 1. Contrast-enhanced, soft-tissue window CT image of the initial CT scan, displaying a large, destructive heterogeneously contrast-enhancing, left-sided nasal mass, extending into the right nasal cavity invading into the right size with destruction of the left nasal and maxillary bones.

Figure 1. Contrast-enhanced, soft-tissue window CT image of the initial CT scan, displaying a large, destructive heterogeneously contrast-enhancing, left-sided nasal mass, extending into the right nasal cavity invading into the right size with destruction of the left nasal and maxillary bones.

A diagnostic workup for nasal tumors includes obtaining a sample of cells, usually through a biopsy to establish a definitive diagnosis. Options for biopsy include transnostril core sampling, blind or rhinoscopy-guided pinch biopsy, nasal flushing or punch biopsy of facial deformities. The latter option was performed on Oscar and histopathology revealed nasal adenocarcinoma. Staging tests then helped to determine the extent of disease through the body as well as a dog’s general health. These tests included blood work with a complete blood count and serum chemistry profile, urinalysis, chest x-rays, abdominal ultrasound and aspirates of the regional lymph nodes (if enlarged). This information is used to develop the best treatment plan for an individual patient. Oscar’s blood work and urinalysis were unremarkable. An abdominal ultrasound revealed hepatic and splenic nodules. Ultrasound-guided fine needle aspiration of the hepatic nodules revealed moderate hepatocyte vacuolization, a suggestion of glycogen deposition, and fine needle aspiration of the spleen revealed reactive lymphoid tissue. The mandibular lymph nodes were aspirated and found to be reactive. Oscar subsequently underwent a CT scan of his head for radiation therapy planning and a thoracic CT scan to complete staging. The CT scan revealed a large (1.7 x 2.7 x 3.1 cm), destructive, heterogeneously contrast-enhancing, left-sided nasal mass, extending into the right nasal cavity invading into the right size (Figure 1). The mass was causing destruction of the left nasal and maxillary bones, the right and left aspect of the cribriform plate and the left palatine and frontal bones with extension into the left retrobulbar space. The left mandibular lymph node was mildly enlarged. There was no evidence of pulmonary metastasis.

Treatment
Nasal carcinomas are the most common type of nasal tumor in dogs, accounting for ≥50-75% of all nasal tumors in dogs. Nasal tumors are relatively common in older dogs and long-nosed dog breeds seem to be predisposed. Nasal cancer is a progressive disease, that mostly affects dogs through space occupation, local destruction, and invasion of nearby tissues and can lead to clinical signs such as nasal discharge, nose bleeds, facial deformity, and occasionally neurologic deficits (such as seizures). Metastatic potential to other areas of the body is low with nasal carcinomas (<30% metastatic rate), but it can happen, and usually occurs in the lymph nodes and lungs, often later in the disease course.

Surgery is not typically recommended for nasal tumors in dogs due to the location of the tumor and inability to remove the entire tumor.

Definitive radiation therapy allows for the best control over future tumor growth with the average survival time being 1 to 1.5 years for most nasal tumors. This treatment plan typically involves 16-19 daily treatments (M-F) under a light plane of general anesthesia. There are some short- and long-term side effects associated with definitive radiation therapy. Short-term side effects typically arise midway through the treatment cycle and peak around the end or 1 week following completion of radiation therapy before healing. Short-term effects include: dry eye and/or conjunctivitis; erythema, hair loss, and dry or moist desquamation of the skin; and inflammation to the oral cavity and throat. We typically manage these short term side effects with oral antibiotics (if indicated), anti-inflammatory medications, pain medications, and topical eye medications. There is also a small risk of long-term effects from radiation therapy, which may develop several months to years after treatment has finished. These effects include: chronic nasal discharge/sneezing, dry eye, cataracts (typically begin to develop around 9-12 months post radiation), bone or soft tissue damage/cell death, and rarely (<3-5% incidence at 3-5 years post radiation) secondary tumor induction.

A less aggressive course of radiation, termed palliative radiation therapy, may also be considered. This treatment protocol typically involves either 6 once weekly treatments or 10 daily radiation treatments (M-F), but other protocols are also available. Palliative radiation generally decreases the number and severity of the potential short-term side effects mentioned above to a very mild level, if at all. This treatment plan is associated with a median survival time of approximately 6-10 months for nasal tumors.

Figure 2. Graphical representation of Oscar’s 3-D conformal radiation therapy plan. The target volume is represented by the red shaded region. The concentric colored lines represent the dose level as a percentage of prescription dose.

Figure 2. Graphical representation of Oscar’s 3-D conformal radiation therapy plan. The target volume is represented by the red shaded region. The concentric colored lines represent the dose level as a percentage of prescription dose.

Although radiation therapy is considered the gold standard for treatment of nasal tumors, chemotherapy can also be considered. There are two different chemotherapy options: conventional and non-conventional chemotherapy. Conventional chemotherapy for treatment of nasal tumors is typically intravenous therapy with a platinum agent, such as cisplatin or carboplatin. Reported response rates are low at approximately 30%. Non-conventional chemotherapy for treatment of nasal carcinomas includes use of the small molecule inhibitor, Palladia. There is little clinical research regarding response rates with Palladia treatment in nasal carcinomas but anecdotally it seems to have some efficacy.

Figure 3. Contrast-enhanced, soft-tissue window CT image of recheck scan at 7 months post radiation  therapy, displaying resolution of the previously described contrast enhancing soft tissue mass associated  with the nasal cavities but persistent loss of the left nasal and maxillary bones.

Figure 3. Contrast-enhanced, soft-tissue window CT image of recheck scan at 7 months post radiation therapy, displaying resolution of the previously described contrast enhancing soft tissue mass associated with the nasal cavities but persistent loss of the left nasal and maxillary bones.

In the case presented herein, after discussion with the owners, definitive radiation therapy was performed. Oscar underwent 16 daily radiation therapy treatments (Figure 2). Halfway through the radiotherapy course, the facial deformity was nearly completely resolved. Epistaxis also resolved. He experienced moderate inflammation to his skin and oral cavity secondary to the radiation therapy, which resolved by 2 weeks post radiation therapy. Oscar was subsequently monitored every 3 months via physical exam and thoracic radiographs. Repeat CT scan at 7 months post radiation therapy revealed complete resolution of the previously described contrast enhancing soft tissue mass associated with the nasal cavities (Figure 3). There was persistent right displacement of the nasal septum and loss of the majority of the left nasal turbinates, as well as persistent loss of the left nasal and maxillary bones, left palatine bone, and right and left cribriform plate.