Early detection of cancer in dogs and cats

Many dogs and cats develop cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. during their lifetime. The proportion of cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. as a cause of death is also high.

The lifetime risk of developing cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. is approximately 25–33% in dogs (1 in 4 to 1 in 3 animals) and approximately 20% in cats (1 in 5 animals) (https://www.akc.org/expert-advice/health/cancer-in-dogs/). The proportion of cancer-related deaths is estimated at 27–34% in dogs and 32–35% in cats of all causes of death (https://pmc.ncbi.nlm.nih.gov/articles/PMC11025767/). Significant breed-related differences are to be expected, especially in dogs. For cats, studies primarily involve older and geriatric animals, so the information on lifetime risk and the proportion of cancer-related deaths is likely somewhat overestimated (https://oncodaily.com/oncolibrary/cancer-in-cats).

In human medicine, a four times higher survival rate has been proven with early detection. Specifically, blood tests represent a promising solution for the early detection of cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas.. In veterinary medicine, however, an improvement in survival time with early detection has not yet been clearly scientifically proven.

 

What methods of early cancer detection are available for dogs and cats?

Regular clinical examination for screening

A regular, annual clinical examination is recommended for all dogs and cats. This should be done annually for younger animals, up to about 7 years of age. In older dogs, very large breeds, and particularly at-risk breeds, semi-annual to annual clinical examinations, including laboratory tests (complete blood count, blood chemistry, urine) and blood pressure measurement, are recommended from 6 to 7 years of age. These systematic check-ups can serve for the early detection of clinically silent neoplasms (e.g., subcutaneousSubcutaneous means “under the skin.” In medicine, it refers to the administration of drugs or the placement of implants directly under the skin. nodules).

The following should be assessed:

• Skin/subcutaneous tissue
• PeripheralPeripheral refers to areas located outside the central part of a system or body. In veterinary medicine, this can refer to peripheral nerves, blood vessels, or tissues that are distant from central organs such as the heart or brain. lymph nodes
• Assessment of the oralOral means “through the mouth” and refers to the intake of food, medication, or other substances through the mouth. In veterinary medicine, many treatments are administered orally. cavity
• Rectal examinationA rectal examination is a clinical examination method in which a doctor or veterinarian inserts a finger or instrument into the anus to check the rectum and surrounding structures for abnormalities. dog (perianal, prostate)
• PalpationPalpation is an examination method in which the condition of body tissues is assessed by feeling them with the hands. It is used to identify swelling, pain, or other abnormalities. of the AbdomenThe abdomen, also known as the abdominal cavity, is the part of the body located between the rib cage and the pelvis. It houses several important organs, including the stomach, liver, kidneys, intestines, and spleen.
• PalpationPalpation is an examination method in which the condition of body tissues is assessed by feeling them with the hands. It is used to identify swelling, pain, or other abnormalities. of the skin and mammary glands

A fine-needle aspirationFine-needle aspiration is a minimally invasive diagnostic technique that uses a thin needle to extract cells or fluid from a tumor, lesion, or organ. This sample is then examined microscopically to make a diagnosis. (FNA) of any palpable massIn pathology, the term “mass” is used to describe an abnormal lump or growth in the body. A mass can form in the skin or subcutaneous tissue, or even inside the body. The causes can be benign (not cancer) or malignant (cancer). is the most effective early detection of solid Tumors on the body surface.

 

Imaging as a screening aid

Thorax / chestThe thorax / chest is the upper part of the trunk, surrounded by the ribs, sternum, and spine. It protects vital organs such as the heart and lungs. X-rayX-ray is an imaging technique that uses X-rays to create images of the inside of the body. It is often used to diagnose bone fractures, lung diseases, and other conditions. and AbdomenThe abdomen, also known as the abdominal cavity, is the part of the body located between the rib cage and the pelvis. It houses several important organs, including the stomach, liver, kidneys, intestines, and spleen. ultrasoundUltrasound refers to sound waves that are above the hearing threshold of the human ear. In medicine, ultrasound is used for diagnostic imaging procedures to visualize internal organs, tissues, and blood flow. are useful “according to the findings,” i.e., if there are suspicious findings, e.g., in the case of unclear laboratory and clinical findings. A general annual X-rayX-ray is an imaging technique that uses X-rays to create images of the inside of the body. It is often used to diagnose bone fractures, lung diseases, and other conditions. examination of the thorax / chestThe thorax / chest is the upper part of the trunk, surrounded by the ribs, sternum, and spine. It protects vital organs such as the heart and lungs. or a general ultrasoundUltrasound refers to sound waves that are above the hearing threshold of the human ear. In medicine, ultrasound is used for diagnostic imaging procedures to visualize internal organs, tissues, and blood flow. examination of the abdominalThe term “abdominal” refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. and pelvic region are not recommended (https://pubmed.ncbi.nlm.nih.gov/36584321/).

 

Laboratory diagnostics as a screening aid

• Basic laboratory values (complete blood count, blood chemistry, urine)

Abnormalities such as unexpected anemia, thrombocytopeniaThrombocytopenia is a condition in which the number of platelets in the blood is lower than normal, increasing the risk of mild to severe Bleeding., hypercalcemia, hyperglobulinemia, Hematuria, etc. can provide early indications of possible cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. and should always be cause for further investigation (https://pubmed.ncbi.nlm.nih.gov/36584321/).

• FeLV/FIV tests (cats)

These tests indirectly serve early detection, as there are a number of FeLV-associated neoplasms. Regular testing is recommended for risk groups. (Life stage guidelines, https://pubmed.ncbi.nlm.nih.gov/33627003/).

• BRAF test (dog, non-invasive, molecular genetic urine test)

This test is not indicated annually, but is urgently indicated if there is a suspicion of urothelial carcinomaA carcinoma is a type of cancer that originates in the epithelial cells that line the inner and outer surfaces of the body. Carcinomas are the most common form of cancer. (UC, transitional cell carcinomaA carcinoma is a type of cancer that originates in the epithelial cells that line the inner and outer surfaces of the body. Carcinomas are the most common form of cancer., urothelial carcinomaA carcinoma is a type of cancer that originates in the epithelial cells that line the inner and outer surfaces of the body. Carcinomas are the most common form of cancer. of the bladder, urethra, and prostate). Suspicious signs are urinary symptoms such as Urinary urgency (pollakiuria) and Blut im Harn (Hämaturie). This test should also be used if imaging accessibility is poor. The test has high reliability (high specificity, good sensitivity) with a detection rate of approximately 85–95%. It is also suitable for monitoring the course of the disease. https://www.antechdiagnostics.com/test/cadet-braf/

Blood-based multi-cancer tests (dog), “Liquid Biopsy”

• Multi-cancer tests are novel tests that can detect multipleMultiple means manifold or repeated and is used to describe conditions or events that occur in multiple instances or at different locations. In veterinary medicine, this may indicate multiple lesions, tumors, or other pathological changes. types of cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. in the blood based on various biomarkers released by cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. cells. They enable cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. diagnostics at a very early stage. However, the reliability of positive and negative findings varies.
• The tumorA tumor is an abnormal growth of tissue that can be benign or malignant. Tumors can develop in any part of the body and affect various functions. DNADNA (deoxyribonucleic acid) is the molecule that carries the genetic instructions for the development, function, and reproduction of all known living organisms and many viruses. It is located in the cells of an organism and contains the information for heredity. test “OncoK9,” a multi-cancer test for dogs, has unfortunately no longer been available since 2024. Studies showed high specificity (approx. 98%) and moderate overall sensitivity (approx. 55–62%) across many tumorA tumor is an abnormal growth of tissue that can be benign or malignant. Tumors can develop in any part of the body and affect various functions. types. There was a high detection rate for systemic, usually particularly aggressive Tumors such as lymphoma, hemangiosarcoma, and osteosarcoma. Localized, solid Tumors were less well detected. The test was particularly useful for use in at-risk patients (age, breed, pre-existing conditions) as a supplement to clinical examination, FNA and imaging.

• Nucleosome/epigenetics tests (Nu.Q Vet) in dogs are also blood tests for detecting systemic cancers. The manufacturers state a specificity of approximately 97%, although this test is also expected to have higher sensitivity for systemic Tumors (lymphoma, hemangiosarcoma) and lower sensitivity for localized solid Tumors. The test is not tumor-specific. Inflammatory conditions can lead to false positive results. The use of this test is useful as an additional screening in seniors and at-risk breeds, although positive results always require imaging and/or Zytologie confirmation (https://volition.com/nu-q-vet/).

Even though blood tests (Liquid BiopsyA biopsy is a medical procedure in which a small amount of tissue is removed from the body to be examined under a microscope for signs of disease. Biopsies can help diagnose cancer and other conditions.) for early cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. diagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. in dogs are promising, a cautious routine application is currently recommended due to the still insufficient, reliable data on patient outcome. Appropriate consultation and decision-making with the pet owner is necessary (https://www.veterinarypracticenews.com/cancer-diagnostics-evidence/).

Practical tips

• What tumor-specific early detection is available?

1. Mammary Tumors (dog/cat)
2. PalpationPalpation is an examination method in which the condition of body tissues is assessed by feeling them with the hands. It is used to identify swelling, pain, or other abnormalities. is the most effective “early detection” for mammary Tumors and the best Prophylaxe is early Ovariohysterektomie (dog). This significantly reduces the risk of mammary Tumors (generally accepted evidence; in senior guidelines as part of the medical historyThe medical history is the systematic collection of a patient’s medical history through questioning. It includes information about previous illnesses, treatments, allergies, and lifestyle habits./prevention) (https://pubmed.ncbi.nlm.nih.gov/36584321/).
3. Tumors of the oralOral means “through the mouth” and refers to the intake of food, medication, or other substances through the mouth. In veterinary medicine, many treatments are administered orally. cavity (cat, squamous cell carcinomaA carcinoma is a type of cancer that originates in the epithelial cells that line the inner and outer surfaces of the body. Carcinomas are the most common form of cancer.)
4. A regular examination of the oralOral means “through the mouth” and refers to the intake of food, medication, or other substances through the mouth. In veterinary medicine, many treatments are administered orally. cavity in connection with professional dental care in dogs and cats is the basis. This allows the most common solid Tumors in cats to be detected at the earliest stage. (Life stage/senior guidelines, https://pubmed.ncbi.nlm.nih.gov/33627003/).

• What is (not yet) proven

1. General abdominalThe term “abdominal” refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. ultrasoundUltrasound refers to sound waves that are above the hearing threshold of the human ear. In medicine, ultrasound is used for diagnostic imaging procedures to visualize internal organs, tissues, and blood flow. screenings to detect hemangiosarcomas in order to prevent Emergencies caused by hemangiosarcoma ruptures are not sensitive to small Lesions and do not provide a proven benefit as a broad preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. program. This means that targeted ultrasoundUltrasound refers to sound waves that are above the hearing threshold of the human ear. In medicine, ultrasound is used for diagnostic imaging procedures to visualize internal organs, tissues, and blood flow. examinations are useful, but an annual routine screening is not recommended.
2. Population-wide “cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. blood screening” (every senior, every year) currently has no guideline recommendation. It is used individually, risk-adjusted and only as a supplement to classic preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. (https://www.aaha.org/resources/2023-aaha-senior-care-guidelines-for-dogs-and-cats/).

• At-risk patient

Check-ups should be carried out annually up to a middle age (7–8 years), and semi-annually–annually in older animals. A check-up includes: Anamnese (previous report), clinical examination, including skin, lymph nodes, oralOral means “through the mouth” and refers to the intake of food, medication, or other substances through the mouth. In veterinary medicine, many treatments are administered orally. cavity and rectal examinationA rectal examination is a clinical examination method in which a doctor or veterinarian inserts a finger or instrument into the anus to check the rectum and surrounding structures for abnormalities. (dog), complete blood count, clinical chemistry, urine examination and blood pressure. Everything Palpable is punctured (FNA). Imaging is performed depending on the indicationIndication refers to a valid reason or rationale for using a specific treatment, medication, or medical procedure. It is based on the diagnosis and the patient’s clinical condition. (https://www.aaha.org/resources/2023-aaha-senior-care-guidelines-for-dogs-and-cats/).

 

1. Urinary symptoms → consider urine-BRAF. If the findings are positive → imaging + Zytologie or Biopsie (https://www.antechdiagnostics.com/test/cadet-braf/).
2. Senior dog, special breeds, special critical medical historyThe medical history is the systematic collection of a patient’s medical history through questioning. It includes information about previous illnesses, treatments, allergies, and lifestyle habits. → Liquid BiopsyA biopsy is a medical procedure in which a small amount of tissue is removed from the body to be examined under a microscope for signs of disease. Biopsies can help diagnose cancer and other conditions. as an additional option (clarification regarding sensitivity, specificity and, if positive → targeted imaging, Feinnadelaspiration and Biopsie necessary) (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0266623).

 

• Cat

1. The FeLV/FIV status should be kept up to date, as a number of Tumors are indirectly associated with FeLV or FIV.
2. A consistent oralOral means “through the mouth” and refers to the intake of food, medication, or other substances through the mouth. In veterinary medicine, many treatments are administered orally. cavity inspection during (annual) dental Prophylaxe contributes significantly to the early detection of squamous cell carcinomaA carcinoma is a type of cancer that originates in the epithelial cells that line the inner and outer surfaces of the body. Carcinomas are the most common form of cancer. of the oralOral means “through the mouth” and refers to the intake of food, medication, or other substances through the mouth. In veterinary medicine, many treatments are administered orally. cavity, the most common malignantMalignant means “cancerous” and is used to describe tumors or neoplasms that grow invasively and have the ability to metastasize. Malignant tumors can cause serious health problems in dogs and cats. TumorA tumor is an abnormal growth of tissue that can be benign or malignant. Tumors can develop in any part of the body and affect various functions. in cats (https://pubmed.ncbi.nlm.nih.gov/33627003/).

 

Conclusion

• The gold standard of early cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. detection remains the consistent annual check-up in dogs and cats up to middle age or the semi-annual clinical check-up in at-risk patients. In the event of unclear and/or suspicious findings, FNA or Biopsie and targeted imaging should follow immediately.
• Liquid BiopsyA biopsy is a medical procedure in which a small amount of tissue is removed from the body to be examined under a microscope for signs of disease. Biopsies can help diagnose cancer and other conditions. tests in dogs are promising additions with high specificity, but limited in overall sensitivity, mainly in local Tumors, and are therefore not yet a substitute for classic diagnostics. Use should be selective and after informing the owners.