Open 24 hours
Phone 206-204-3366
Fax 206-204-3858

Veterinary Oncology

Chelsea Tripp, DVM, MS, DACVIM (Oncology)

Dr. Tripp received her veterinary degree from the University of Missouri and completed an internship at Animal Cancer Specialists here in Seattle. She is returning home after completing her three-year residency in medical oncology at Washington State University. She also completed a master’s degree at Washington State University looking at the methylation status of lymphoma in dogs. Dr. Tripp is board certified in medical oncology by the American College of Veterinary Internal Medicine.  

Dr. Tripp’s areas of interest include client education, oncologic emergencies, clinical pathology, electrochemotherapy, palliative care, and improving the quality of life for end-stage cancer patients. The focus of her approach to the practice of oncology is compassionate care and strengthening the human-animal bond.

Dr. Tripp is a Paul Harris Fellow and active member of the Alderwood-Terrace Rotary. She has many personal interests including traveling, musical theater, baking, and wine tasting. She is the proud parent of four dogs; three Miniature Schnauzers, Nanook, Kuma and Ward, and an Australian Labradoodle named Clover.

Dr. Tripp makes regular guest appearances on the KIRO radio showRaining Cats and Dogs to answer listener questions regarding pet health. 


Megan Breit, DVM, MS, DACVIM (Oncology)

Dr. Megan Breit completed her veterinary degree at Washington State University.  After finishing a rotating Small Animal Medical and Surgical Internship at Animal Hospital Specialty Center in Highlands Ranch, Colorado, she then completed her Specialty Internship in Oncology at Blue Pearl Veterinary Specialists in Tampa, Florida.  At The Ohio State University she completed her three-year Residency in Medical Oncology in addition to receiving a master’s degree while researching a new therapy for canine melanoma. Dr. Breit is board certified in medical oncology by the American College of Veterinary Internal Medicine.  

Dr. Breit’s top priorities are the quality of life of her patients and ensuring their comfort during care.  She is dedicated to providing pet owners with the options and explanations about their pet’s specific cancer in order to assist them in making the best decision for their family.  She is passionate about diagnosing as well as treating cancer, collaborating with the local referring community, and exploring new and better cancer therapies.

Dr. Breit grew up in Bellevue, WA and currently lives with her wonderful husband and 3 pets; her cat Hermione, and 2 dogs Lily and Kylee. She enjoys spending time with her family and doing anything outdoors (snowboarding, running, biking, kayaking, and swimming). 


Types of Cases

Cancers (Malignancies) Based on Location
Adrenal and Pituitary Tumors
Bladder and Urethral Tumors
Bone Tumors (primary and metastatic)
Brain and Spinal Cord Tumors
Cardiac and Heart-based Tumors
Esophageal Tumors
Gall Bladder, Liver, and Pancreatic Tumors
Laryngeal and Tracheal Tumors
Lung Tumors (primary and metastatic)
Mammary Gland Tumors
Mediastinal Tumors
Nasal Tumors
Ocular and Periocular Tumors
Oral and Salivary Gland Tumors
Perianal and Anal Sac Tumors
Prostatic Tumors
Renal Tumors
Reproductive Tumors (male and female)
Rib and Pleural Tumors
Skin, Nail Bed, and Foot Pad Tumors
Skull Tumors
Splenic Tumors
Thyroid and Parathyroid Tumors
Stomach and Intestinal Tumors
Specific Types of Cancer (Malignancies)
Apocrine Gland Adenocarcinoma
Basal Cell Carcinoma
Histiocytic Disease
Leukemia and Lymphoma
Mast Cell Tumor
Multiple Myeloma
Other - Adenocarcinoma, Carcinoma, Sarcoma, Undifferentiated
Soft Tissue Sarcoma
Squamous Cell Carcinoma
Transitional Cell Carcinoma


Contact Us

Normal hours of operation: 
Monday through Saturday

Emergency Services  24 Hours

Phone: (206) 204-3366

Fax: (206) 204-3858

Address: 14810 15th Avenue NE, Suite B, Shoreline, WA 98155


Oncology Services / Definitions Directory


Chemotherapy can be used alone for cancers/tumors that affect multiple areas of the body, such as lymphoma, leukemia, and metastatic tumors. Chemotherapy can also be used in combination with surgery and/or radiation therapy to slow or stop localized tumors from spreading to other areas of the body when this is a concern. Different chemotherapy protocols are used for different cancers/tumors, so the plan will be individualized to meet your pet’s needs.

Comprehensive Examination and Evaluation

At the time of your initial consultation, Dr. Tripp will perform a thorough physical exam, review all medical records, discuss your pet’s diagnosis, and answer any questions that you have. Further recommendations regarding diagnostics and treatments will be made as indicated. Not all cancers are created equally, so the plan will be individualized to meet your pet’s needs.

Consultation and Referral for Advanced Imaging

Occasionally, three-dimensional imaging, such as CT or MRI may be recommended to obtain additional information about a tumor/cancer prior to moving forward with treatment. These modalities may be recommended to look for subtle changes that may not be picked up with standard x-rays alone and are particularly important in planning for radiation therapy and in planning for surgeries in some delicate areas. A referral to an imaging center can be provided if indicated.

Consultation and Referral for Radiation Therapy

Radiation therapy is sometimes recommended to kill any remaining microscopic tumor cells that may be present near the surgical scar when a tumor cannot be completely removed with a good margin of normal tissue. It is also sometimes used as a palliative treatment, or a treatment aimed at improving pain and quality of life. Different radiation protocols are used for different cancers/tumors, and a referral for radiation therapy can be provided if indicated.

Coordination for Oncologic Surgery

Surgical removal with a good margin of normal tissue is the first step in treating many localized tumors. If surgery is recommended for your pet, we will discuss this with our surgeon and work with you to schedule this in a timely manner. For most patients, a few days/nights of hospitalization are recommended following surgery for close monitoring and pain control.

Courtesy Phone Consultations for Referring Veterinarians

Phone consultations are offered to primary care family veterinarians Monday-Thursday during regular business hours. Basic diagnostic and treatment options as well as cost estimates can be discussed during these consultations. Referral for a consultation is encouraged for any client/patient interested in advanced cancer diagnostics and treatments.

Diagnostic Tests for Confirmation of Diagnosis and Cancer Staging

Further diagnostic testing is often needed in order to make definitive treatment recommendations and to determine prognosis. Diagnostic recommendations may include but are not limited to lab work, x-rays, ultrasound, fine needle aspirates, biopsies, and/or advanced imaging, such as CT or MRI.


Another new novel therapy is being used for treatment of superficial tumors.  This is a modality that is widely used in Europe in exchange of radiation therapy.   Surgery is usually pursued first and if the margins are close or “dirty”, electrochemotherapy may be able to be used to clean up what was left behind.

Emergency Advice for Established Clients

The oncology team is available Monday-Thursday during normal business hours. Our emergency service is open 24 hours a day, 7 days a week if you have after hours concerns or questions. The oncology service is on call to answer questions about existing oncology patients and can be contacted by one of our emergency doctors if needed. Weekend and after hours new oncology referrals are handled on a case by case basis.

Hospice Care for Patients with End-stage Cancer

Saying goodbye to a beloved family member can be difficult. The oncology team is here to help guide you during this difficult time and can help your pet to maintain a good quality of life and live comfortably until natural death or euthanasia occurs. This may include but is not limited to pain management, nutritional advice, urinary bladder management, end of life care, and referral to a support group.


Treatments that modulate how the immune system works can be administered to stimulate or suppress certain immune functions that play a role in the body’s ability to recognize and fight cancer. Options for immunotherapy are currently very limited in veterinary medicine, but there is ongoing research in this area. Oncept™ (cancer vaccine for melanoma), imiquimod cream, and metronomic chemotherapy are three examples of how immunotherapy can be used in veterinary medicine.

Management of Chemotherapy Side Effects

Chemotherapy is generally very well-tolerated in dogs and cats. Side effects are rare but can include lethargy, decreased appetite, vomiting, diarrhea, and drops in the white blood cell and platelet counts. Often, these side effects can be treated on an outpatient basis, but hospitalization for more intense supportive care is occasionally recommended.

Small Molecule Inhibitors

Small molecule inhibitors act selectively against molecular targets expressed in some tumors and can interfere with tumor growth and progression. This is also a growing area of interest in veterinary oncology, and the oral drugs Palladia® and Kinavet-CA1® are commercially available and approved for treatment of mast cell tumors in dogs. They are also occasionally used for other tumor types.