Early Cancer Detection in Pets: Understanding Screening Tests and Client Education Tools
By Michelle Silver, DVM, DACVIM (Oncology)
DVM STAT Oncologist
Why Cancer Screening Matters
Cancer is one of the most common health concerns in companion animals today. Approximately 6 million dogs are diagnosed with cancer each year in the United States, and according to a study by the Animal Morris Foundation, 41% of pet owners identify cancer as their greatest health worry—far above heart disease, which ranks second at only 7%.
One in four dogs will develop cancer during their lifetime, and almost half of all dogs over the age of 10 are at risk of developing the disease.
The good news is that advances in veterinary diagnostics are allowing us to detect cancer earlier—sometimes before obvious symptoms appear. Early detection can improve long-term outcomes, guide treatment decisions, and give pet owners valuable time to act.
Understanding Cancer Screening Tests
There are now several canine cancer screening tests available to help aid in the early detection of cancer. The goal of these tests is to detect disease at an early stage, to hopefully improve the long term outcomes.
These tests do not determine the type or specific location of the cancer, rather the tests are to designed to determine whether a patient should undergo additional diagnostics/screening for possible cancer.
Samples may consist of blood, urine, or saliva, depending on the test. Most are recommended for dogs over 7 years old, or for at-risk breeds beginning at age 4.
Current Cancer Screening Tools
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Sample type: Fasted blood sample
Mechanism: Evaluates nucleosomes. When a patient (human or canine) has cancer, nucleosomes from those cancer cells are released into the blood, and they can be measured using antibodies that are specific to nucleosomes.
Detection performance:
82% hemangiosarcoma
77% lymphoma
54% histiocytic sarcoma
97% specificity and 76% sensitivity for lymphoma and hemangiosarcoma
Sensitivity for localized solid tumors such as mast cell tumors and osteosarcoma was much lower. The sensitivity was 50% or less for melanoma, osteosarcoma, soft tissue sarcoma and mast cell tumors at 97% specificity.
Exclusion criteria:
Not fasted for at least 4 hours prior to draw
Acute inflammatory process:
Immune mediated diseases, systemic inflammation, sepsis, trauma, skin infection/allergy flare-up, acute pancreatitis
Next steps:
Moderate risk: Repeat in 2–4 weeks if fasted and otherwise healthy
Moderate to high risk: Review history, check for masses or enlarged lymph nodes, and consider additional diagnostics (routine lab work, chest x-rays, abdominal ultrasound)
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Sample type: Blood sample
Focus: Currently limited to lymphoma detection. However, there is ongoing research to expand coverage for other common canine cancers.
Performance: 99% specificity and 79% sensitivity
Recommendations:
If negative, recheck at annual exams
If positive but no clinical signs, repeat in 1–2 months
If positive and symptomatic, pursue diagnostics such as chest radiographs, abdominal ultrasound, cytology, or flow cytometry
If positive, look for any evidence of illness or signs consistent with lymphoma.
If there are none and patient is otherwise healthy, recommend repeating test in 1-2 months
If patient is symptomatic, then consider additional diagnostics (chest x-rays, abdominal ultrasound, cytology, flow cytometry, etc)
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Owners can order the kit online and collect the sample themselves.
Sample type: Urine (collected at home by the owner)
Cancer types screened: Hemangiosarcoma, lymphoma, mast cell tumor, and melanoma
Method: Uses nemadotes (worms) strong olfactory system and found that they are more attracted to the urine of cancer patients.
Performance: 96% specificity and 85% sensitivity
This test is used in Japan as a screening test for people and is called the N-Nose test.
The test has been quite controversial due to the high false incidence rates reported by some hospitals in Japan.
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Owners can order the kit online and collect the sample themselves.
Sample type: Saliva (collected at home by the owner)
Method: Relies on trained scent-detection dogs to detect volatile organic compounds in the saliva sample.
Cancers evaluated: Lymphoma, mast cell tumor, osteosarcoma, melanoma, soft tissue sarcoma, squamous cell carcinoma, urothelial cell carcinoma.
A research team from the University of Alabama at Birmingham and University of Wisconsin-Madison, in collaboration with ScoutMD, evaluated the test’s accuracy using samples from 139 dogs with cancer.
In their analysis of 10 cancer samples and 22 healthy controls, six trained dogs distinguished between groups with 90% mean sensitivity and 98% mean specificity.
It is important to note that the sample size for this study was significantly smaller than for Nu-Q and Cancer Dx and larger studies are needed.
Putting It All Together: Screening as a Preventive Tool
Cancer screening tests are not diagnostic endpoints—they are decision-support tools that can help guide whether further imaging, cytology, or laboratory work is warranted. Used thoughtfully, these tests can help veterinarians and pet owners stay one step ahead of disease.
Resources You Can Use Today — Free from DVM STAT
To help you incorporate early-detection conversations into daily practice, we’ve created two free tools:
📄 Cancer Screening Test Summary (PDF) – A reference for veterinary teams summarizing available screening options, sensitivity/specificity data, and testing recommendations.
🐾 Client Handout: 10 Warning Signs of Cancer in Dogs and Cats (PDF) – A printable, client-facing guide for at-home monitoring and follow-up care.
Both are free to download and share with your clients.
Free Client Education Handout
Our oncology team created a client education handout to make early cancer detection simpler and more effective for both veterinarians and pet owners. It’s designed to complement your preventive-care discussions and empower clients to spot concerning changes early.
We recommend printing or sharing this guide during:
Annual wellness visits and early-detection discussions
Senior pet checkups and preventive-care programs
At-home monitoring conversations
Post-visit follow-up emails or take-home resources
You can download and distribute it freely in your clinic.
What’s Inside
10 Warning Signs of Cancer in Dogs and Cats
Written by DVM STAT’s board-certified oncologists, this guide outlines the most common early indicators that warrant veterinary follow-up:
✔️ Unexplained weight loss
✔️ Lumps, bumps, or swellings that persist or grow
✔️ Changes in appetite or drinking habits
✔️ Chronic vomiting, diarrhea, or non-healing sores
✔️ Persistent cough, lethargy, or behavior changes
Each sign is explained in simple, client-friendly language, helping pet owners understand what to look for and when to schedule a visit—without causing unnecessary alarm.
You’ve Made an Early Diagnosis. Now What?
Early detection is just the beginning. Once cancer is suspected or confirmed, the next step is choosing the right diagnostic and treatment path—and that’s where DVM STAT’s Oncology Service can help.
Our board-certified oncologists provide comprehensive teleconsultation support for general practitioners, mobile veterinarians, urgent care teams, and specialty hospitals. We partner directly with you to co-manage cases, ensuring pets receive the highest level of care without requiring immediate referral or travel to a specialty center.
Here’s what you can expect from a DVM STAT oncology consult:
Detailed review of 3–6 months of medical history, lab work, and imaging
Guidance on diagnostic and staging strategies
Evidence-based treatment protocols for both curative and palliative intent
Continuity of care—you’ll work with the same specialist from case to case
Accessible, affordable collaboration via phone or video with included follow-up support
Whether you’re developing a treatment plan, discussing quality-of-life options, or seeking clarity on next steps, DVM STAT’s oncology team serves as an extension of your hospital—supporting you, your team, and your clients every step of the way.
Closing Thought
As diagnostic innovation grows, so does our ability to identify disease earlier and improve outcomes for pets. Whether you’re using these tools for senior wellness care, breed-specific risk assessment, or as part of your preventive-medicine protocol, DVM STAT’s oncology team is here to help guide you and your clients every step of the way.