Oncologic MRI & Tumor Mapping for Dogs & Cats
When a pet is diagnosed with cancer, understanding the full extent of the tumor is essential for planning effective treatment. Surgery, radiation therapy, and chemotherapy all depend on knowing precisely where the tumor begins and ends, what structures are involved, and whether there are additional lesions that need to be addressed.
At Sage Veterinary Imaging (SVI), our 3-Tesla MRI provides the soft-tissue detail that oncologic treatment planning demands. MRI excels at defining tumor margins, identifying infiltration into surrounding tissues, mapping tumors for radiation therapy, and monitoring treatment response over time. For soft-tissue tumors, MRI reveals critical details that CT alone cannot provide.
SVI offers advanced MRI services at our centers in Round Rock, Texas; Spring, Texas; and Sandy, Utah.
Oncologic MRI Applications
Oncologic MRI serves multiple roles in cancer care — from initial staging and surgical planning to radiation therapy mapping and post-treatment monitoring. Below are the key applications where MRI adds the most diagnostic value.
Soft Tissue Sarcoma & Margin Assessment
Soft tissue sarcomas are among the most common tumors in dogs, and achieving clean surgical margins is the single most important factor in preventing recurrence. MRI maps the true extent of these tumors with far greater accuracy than physical examination or CT, showing tumor infiltration along fascial planes, involvement of adjacent muscles, and proximity to vital structures. For pets with previously incompletely excised tumors, MRI identifies residual disease and guides revision surgery or radiation therapy planning.
Learn more about soft tissue sarcoma imaging →Infiltrative Tumor Assessment
Some tumors grow by infiltrating along tissue planes rather than forming well-defined masses, making them particularly challenging to assess on physical exam or CT. MRI’s superior soft-tissue contrast reveals the true boundaries of infiltrative tumors, including extension along nerves (perineural spread), invasion of muscle compartments, and involvement of blood vessels. This mapping is essential for determining whether surgical resection is feasible and planning adequate margins.
Learn more about infiltrative tumor assessment →Radiation Therapy Planning
Modern radiation therapy requires precise definition of the tumor volume and surrounding normal tissues to deliver maximum dose to the cancer while minimizing damage to healthy structures. MRI provides the soft-tissue detail needed to define tumor boundaries for radiation planning, particularly for brain tumors, nasal tumors, and soft-tissue sarcomas where CT alone may underestimate tumor extent. MRI-based planning improves treatment accuracy and reduces side effects.
Learn more about radiation therapy planning →Post-Treatment Monitoring
After surgery, radiation, or chemotherapy, monitoring for tumor recurrence or treatment response is essential for ongoing cancer management. MRI distinguishes between post-treatment changes (scar tissue, radiation-induced changes) and true tumor recurrence — a distinction that CT and physical exam often cannot make. Serial MRI studies can track tumor size changes over time, assess whether treatment is working, and detect recurrence early when additional intervention may still be effective.
Learn more about post-treatment monitoring →Multi-Modal Oncologic Staging
Many cancer patients benefit from combining MRI’s soft-tissue detail with CT’s speed for bone and lung evaluation. At SVI, we offer both modalities under the same roof, allowing comprehensive staging in a single anesthesia session. For example, a dog with a brain tumor may receive brain MRI for surgical or radiation planning plus chest CT for metastasis screening, all in one visit. This integrated approach minimizes anesthesia events and provides the oncology team with complete information.
Learn more about multi-modal staging →Breeds Commonly Affected
Cancer affects all breeds, but certain breeds have higher rates of specific tumors. Golden Retrievers and Labrador Retrievers have elevated rates of soft tissue sarcomas and lymphoma. Boxers are predisposed to mast cell tumors and brain tumors. Bernese Mountain Dogs have very high rates of histiocytic sarcoma. Flat-Coated Retrievers and Rottweilers are prone to soft tissue sarcomas. Giant breeds like Great Danes and Saint Bernards have higher rates of osteosarcoma. Siamese cats have increased rates of certain tumor types including intestinal and mediastinal lymphoma.
How Oncologic MRI Helps
Oncologic MRI leverages the unmatched soft-tissue contrast of our 3-Tesla system to provide information that directly impacts cancer treatment decisions. Multiple MRI sequences characterize tumor composition, vascularity, and margins from different perspectives, building a comprehensive picture of the cancer that no other modality can provide. Contrast enhancement reveals areas of active tumor growth and helps distinguish viable tumor from necrosis or post-treatment changes.
Each oncologic study is reviewed by our board-certified veterinary radiologists, who provide detailed reports with measurements, margin assessments, and work directly with your veterinarian, surgeon, or oncologist to guide treatment planning.
What to Expect During Your Visit
Oncologic MRI studies typically take 45–75 minutes, depending on the tumor location, size, and the imaging sequences required. Contrast-enhanced images are obtained in virtually all oncologic cases. For patients requiring both MRI and CT staging, both studies can be performed in the same anesthesia session to minimize your pet’s time under anesthesia.
Results are interpreted by a board-certified veterinary radiologist, and your veterinarian or oncologist typically receives a detailed staging report the same day.
Learn more about veterinary MRI at Sage →
Dr. Jaime Sage, DVM, MS, DACVR
Dr. Jaime Sage is the founder of Sage Veterinary Imaging and a board-certified veterinary radiologist (DACVR) with advanced expertise in diagnostic MRI for companion animals. Dr. Sage personally interprets complex cases and works closely with referring veterinarians to ensure every imaging study delivers clear, actionable diagnostic answers.
Her published research on MRI in veterinary medicine — co-authored with Dr. Patrick Gavin, a pioneer in the field — has contributed to advancing the standard of care for pets requiring advanced diagnostic imaging.
Why Choose Sage Veterinary Imaging
Get Answers for Your Pet
If your pet has been diagnosed with cancer and needs advanced imaging for staging, surgical planning, radiation mapping, or treatment monitoring, our oncologic MRI provides the detailed information your veterinary team needs to plan the most effective approach.
Schedule an Oncologic Imaging Study
Visit one of our three locations to learn more and schedule your pet’s oncologic imaging study. Our team will work directly with your veterinarian or oncologist.
Oncologic MRI FAQ
Ready to Get Answers?
Advanced oncologic MRI can provide the tumor detail your veterinary team needs to plan the most effective cancer treatment. Visit one of our locations to get started.