The Pet Owner's Guide to Dog Cancer
The cancer diagnosis strikes fear in the hearts of people worldwide. Unfortunately, cancer attacks our pets as well. If discovered early, you can treat dog cancer, providing your friend with a healthy, happy life.
To win a cancer battle, you must be proactive. To be proactive, you need an understanding of different dog cancer symptoms, treatments, and prevention. Armed with the right knowledge, you will be able to spot dog cancer symptoms as soon as they appear. Often, early identification of cancer is the difference between life and death.
General Dog Cancer Symptoms
`Below is information on the most common cancer symptoms in dogs. If your dog experiences any listed symptoms, seek veterinary care immediately. Please understand the symptoms are not proof of cancer, but are all possible signs of cancer. And remember, the earlier you identify cancer, the better.
Evidence of Pain
An example of pain is obvious limping while your dog is walking, running or playing. Limping is often a sign of arthritis, joint, or muscle issues in older dogs. But, it can also be a sign of bone cancer.
Changes in Bathroom Habits
Accidents do happen! But, accidents are also a possible sign of cancer. Watch for recurring accidents, needing to go to the bathroom more, and blood in the stool or urine.
Lethargy or Depression
If your dog acts more "lazy" or sleeps more than usual, you should pay attention. Sudden loss of interest in playing or going on walks and sleeping more than usual are possible signs.
Coughing or Difficulty Breathing
Coughing or difficulty breathing are common symptoms of heart and lung disease. But, the same symptoms display when cancer metastasizes to the lung s.
Change in Appetite
Oral, esophageal, and digestive tract tumors cause loss of appetite. Cancer also causes general malaise which can make dogs not want to eat.
Many health issues can cause your dog to lose weight. But, if you notice weight loss in combination with any other listed symptom, see your vet.
Wounds that don't heal are a symptom of cancer, infection, or skin disease. Have your veterinarian look at all non-healing wounds.
Abnormal discharges include pus, blood, vomiting, or diarrhea. The discharge can come from anywhere on your dog. Abnormal discharge accumulating inside your dog's body causes a distended or bloated abdomen.
Foul or offensive odors coming from your dog's mouth, ears or elsewhere might be cancer. Even if it's not cancer, it's a sign of infection or disease.
Lumps and Bumps
Not all lumps and tumors are cancerous, but you should still have your vet examine them. A needle cytology is an in-office test used to tell if the abnormality is a cancerous tumor or a simple lipoma. Lipomas are noncancerous fatty tumors affecting many older dogs.
Remember, the above list is not definitive proof of cancer. But, any one of these symptoms is a good reason to visit your veterinarian. Also, understand some forms of cancer are more lethal than other forms of cancer.
For example, your veterinarian most often treats skin cancer with minor surgery. But, dog lymphoma and bone cancer (osteosarcoma) often metastasize through the body. When cancer metastasizes, it often causes death.
If your dog has cancer, "The Dog Cancer Survival Guide" by Demian Dressler is an excellent resource. PET | TAO co-founder and practicing veterinarian Dr. Marc Smith keeps a copy of the book in his clinic.
"The Dog Cancer Survival Guide" is full of helpful information and tips for helping your dog survive cancer.
Specific Cancer Symptoms
Knowing cancer symptoms is a very important part of keeping your dog healthy. The earlier you detect and treat cancer, the better your dog's prognosis will be. Most dog owners will spot a lump and know it might be a cancer symptom. But what about the other types of cancer?
Dog Bone Cancer Symptoms
Bone cancer (osteosarcoma) invades any breed of dog but is most common in larger breeds. Unfortunately, bone cancer quickly metastasizes, spreading throughout the body. The prognosis for bone cancer is usually poor. Symptoms of bone cancer may be either subtle or profound and include:
- Joint Pain
- Bone Pain
- Mass or inflammation around the tumor area
Veterinarians use several tests to analyze and diagnose bone cancer. X-rays, biopsies, blood tests, bone scans, and CAT scans allow your vet to see what's going on inside your pet. The tests also show your veterinarian the severity of your dog's cancer.
Dog Colon Cancer Symptoms
The two types of dog colon cancer are adenocarcinoma and lymphoma/lymphosarcoma.
Adenosarcoma is when tumors grow from the apocrine glands located on each side of the rectum.
Lymphoma/Lymphosarcoma affects the lymph nodes or lymphoid tissues in the gastrointestinal tract.
Dog colon cancer symptoms mimic symptoms of Irritable Bowel Syndrome (IBS) and Colitis. In fact, both chronic diseases sometimes lead to colon cancer.
Signs of colon cancer include:
- Blood in stool
- Mucus in stool
- Increased thirst
- Frequent urination
- Unexplained weight loss
Signs of progressed colon cancer include:
- High fever
- Behavior change
- Hair loss
- Skin rash
- Muscle weakness
Testing for colon cancer often includes urinalysis, blood test, x-rays, colonoscopy, and biopsy.
Dog Liver Cancer Symptoms
The most common form of liver cancer in dogs is hepatocellular carcinoma. Hepatocellular carcinoma is a malignant tumor of the epithelial cells of the liver. Outward symptoms usually don't appear until the liver cancer has reached its final stages.
Liver cancer symptoms include:
- Appetite loss
- Weight loss
- Excessive thirst
- Enlarged liver
- Abdominal hemorrhage
Testing for liver cancer includes an exam, blood work, electrolyte panel, and urinalysis. Your veterinarian might also extract cells from the via needle for a microscopic study. A liver biopsy provides a conclusive diagnosis.
Dog Skin Cancer Symptoms
The most common type of skin cancer is a basal cell tumor. Basal cell tumors form in the deepest layer of the skin, the epithelium, and are most common in older dogs. Though 3-12% of all tumors are basal cell tumors, less than 10% of basal cell tumors are cancerous or malignant. The risk with basal cell tumors is the tumors may spread to other parts of the body including organs.
Skin tumors usually appear as a raised, hairless mass around the head, neck or shoulders. Your veterinarian will be able to diagnose by taking a small sliver of the tumor and examining it. Your vet may also do a urinalysis and a count of all blood cells in the body.
Another common type of skin cancer in dogs is canine Epidermotropic Lymphoma. Canine Epidermotropic Lymphoma spreads through cells in the immune system. Although all dogs are at risk, older dogs have an increased chance developing it.
Symptoms of Canine Epidermotropic Lymphoma include:
- Loss of hair
- Scaly skin
- Redness of skin
- Loss of pigment
- Skin ulcers or masses around eyes, mouth, and nose
Your veterinarian will do a urinalysis and a count of all blood cells in the body. He may take radiographs to look for tumors inside of the dog. Your vet may biopsy the tumor and send it to a veterinary pathologist to confirm the diagnosis.
Dog Stomach Cancer Symptoms
Leiomyosarcoma, or stomach cancer, is very uncommon in dogs. Leiomyosarcoma is when cancerous tumors form in the stomach or intestinal tract. It is painful, targeting dogs over the age of six.
Stomach cancer upsets digestion and metastasizes throughout the body.
- Symptoms include:
- Weight loss
- Blood in stool
To diagnose, your veterinarian may perform a complete physical examination, bloodwork, and urinalysis. Other diagnostic procedures include abdominal X-rays and ultrasounds, contrast radiography, or endoscopy. Endoscopy is sending a tube down the esophagus to examine the stomach and intestines)
Dog Throat Cancer Symptoms
The name for throat cancer in dogs is Chondrosarcoma. Chondrosarcoma occurs when a tumor originating in the cartilage develops in the larynx or trachea. Chondrosarcoma spreads fast and the prognosis is usually bleak.
Symptoms may include:
- Changes in voice
- Loss of bark
- Harsh, noisy breathing
- Poor exercise stamina
- Difficult respiration, breathing with mouth open
- Loud noises while breathing
- Bluish mucous membranes
- Sudden collapse
- Difficult eating
- Inability to swallow
Diagnostic procedures include blood work, urinalysis, or radiographs of throat and neck.
Dog Cancer: Lumps, Bumps, and Tumors
As they age, dogs often get lumps on their body and under their skin. If you notice skin lumps on your dog, you should have the lumps examined by your veterinarian.
Dog skin lumps can be cancerous or noncancerous. A basic knowledge of different types of lumps and bumps on dogs will help you understand what your vet finds during the exam and ask educated questions.
Abscesses are painful collections of pus, usually caused by a bite or a puncture wound. Abscesses are noncancerous.
Basal Cell Tumors
Basal cell tumors are a type of skin cancer in dogs. Basal cell tumors are the most common type of cancer and rarely metastasize or cause death.
Ceruminous Gland Adenomas
Ceruminous gland adenomas are benign tumors in the ear. Ceruminous gland adenomas are noncancerous.
Epidermal Inclusion Cysts
Epidermal inclusion cysts are benign cysts usually found on the skin. Epidermal inclusion cysts are noncancerous.
Hematomas are localized collections of blood outside of the blood vessels. The blood is usually a liquid form within the tissue. Hematomas are commonly found in or on the ear. and are noncancerous.
Histiocytomas are benign tumors caused by an overgrowth of histiocytes (immune cells). Histiocytomas are noncancerous.
Lipomas are benign tumors composed of fatty cells between the skin and muscle tissue. Lipomas are also called fatty tumors. Lipomas are noncancerous.
Mast Cell Tumors
Mast cell tumors are the most common cutaneous tumor found in dogs. Although some are benign, most mast cell tumors are cancerous.
Perianal Gland Tumors
Perianal gland tumors are tumors found near or on a dog's anus. There are two types of perianal gland tumors: perianal gland adenomas and perianal gland adenocarcinomas. Perianal gland adenomas are benign. Perianal gland adenocarcinomas are malignant (cancerous).
Sebaceous adenomas are benign, slow-growing tumors of the sebaceous gland. Sebaceous gland adenomas are noncancerous.
Skin Papillomas are benign epithelial tumors, also known as “skin tags.”
Soft-Tissue Sarcomas are cancerous tumors of the soft tissues of the body.
Transmissible Venereal Tumors
Transmissible venereal tumors are sexually transmitted cancer in dogs.
You'll find many pictures of dog cancer lumps available in books and online. But, there is only one sure way to diagnose your dog’s lump or bump. You must have your veterinarian send a biopsy or cytology to a lab for analysis.
Along with tumors, other signs of dog cancer are:
- Unusual odors
- Weight loss
- Changes in appetite
- Respiratory problems
- Behavior changes
- Open sores
- Vomiting and diarrhea
- Pale gums
Dogs with tumors can often maintain an excellent quality of life. Several options treat tumors and lumps on a dog’s body. Treatment might include surgery, herbal remedies, alternative treatments, and cryotherapy.
How Long Can a Dog Live with Cancer?
Dog cancer survival rates vary depending on the type of cancer and your dog’s age, health, and chosen treatment.
What to Do When Your Dog Has Cancer
- What type of cancer does your dog have?
- How advanced is your dog’s cancer?
- Do you want standard western treatments or alternative and holistic treatments?
- Is surgery recommended for your dog?
You will have to answer all the above questions to determine your options and treatment. There are several basic dog cancer treatment options. Dr. Smith often recommends more than one option at a time.
The effectiveness of each option varies with each pet’s individual situation.
Dog Cancer Treatment Options:
- Surgery - Surgically removing cancerous tumors and lesions
- Radiation - Using radiation (like X-rays) to treat cancer
- Chemotherapy - treating disease using chemical substances. Especially the treatment of cancer by cytotoxic and other drugs.
- Immunotherapy - preventing or treating disease with substances that stimulate the immune response.
- Eastern Herbals
- Alternative Therapies
- Vitamin C IV
- Anti-Cancer Diet
- Natural Treatments
Several natural dog cancer treatments exist today. Natural treatments work alone or in combination with chemotherapy, surgery, and radiation. The most skilled veterinarians analyze a dog's situation and offer several treatment options. With your vet's help, choose the option you feel is best for your dog’s particular needs.
Where and How can I Get My Dog Treated for Cancer?
When it comes to getting your dog treated for cancer, you have several options.
Alternative or Holistic Veterinarian
You'll get extra cancer treatment options using an alternative or holistic veterinarian. Extras might include herbal remedies, acupuncture, supplements, IV therapies, and more.
Dog Cancer Treatment Center
A dog cancer treatment center is a clinic specifically designed to treat dogs with cancer.
A specialty clinic employs staff that specializes in different areas of veterinary medicine.
Dog Cancer Treatments
Obviously, different types of dog cancer will involve different treatment protocols. Treatment protocols will also vary depending on the cancer stage, your dog’s health, and your lifestyle, finances, and goals.
Dog Lymphoma Treatment
Dog lymphoma is a cancer of the lymph nodes. If your dog is diagnosed with lymphoma, there are several treatments available. The complete details of these dog lymphoma treatments will be covered in greater detail later in the article.
Most Common Dog Lymphoma Treatments:
- University of Wisconsin Chop Protocol: The Chop protocol is the most recommended treatment for dogs with lymphoma. The Chop protocol utilizes cyclophosphamide, doxorubicin, vincristine, and prednisone.
- Single Agent Doxorubicin Protocol
- COP Protocol (cyclophosphamide, vincristine or Oncovin, and prednisone)
- Palliative radiation
- Half body radiation
- Bone marrow transplant with total body radiation
Dog Lung Cancer Treatment
Lung cancer is fairly uncommon in dogs but does occur. Lung cancer occurs when carcinomas develop in the lung epithelial tissue. Cancer grows directly in the lung tissue, or in the bronchioles and airways. Dog lung cancer is aggressive and often spreads to the lymph nodes and thoracic tissues.
Most Common Dog Lung Cancer Treatments:
- Surgical excision of the tumor(s)
- Recommended for primary lung tumors.
- Sometimes not possible because of location or size of tumor
- Sometimes used instead of surgery
- Sometimes use in addition to surgery
- Radiation Therapy
- Sometimes used instead of surgery
- Sometimes use in addition to surgery
- Alternative Treatments
- Herbal Therapies
Survival times for dogs with lung cancer usually varies from two months to two years depending on the cancer type and severity.
Dog Liver Cancer Treatment
If your dog's diagnosis is liver cancer, you will need to know which type of liver cancer is present.
Primary Liver Cancer:
- Single, large liver tumors
- Unlikely to spread to other parts of the body
- Good prognosis
Metastatic Liver Cancer:
- Does not originate in the liver
- Has spread from elsewhere in the body
- Usually, causes multiple masses in the liver
Most Common Dog Liver Cancer Treatments
- Surgical Excision
- Alternative Treatments
- Herbal Remedies
Dogs get tumors all the time. In fact, there’s a 50/50 chance your dog will develop a tumor of some type during his or her lifetime. Seeing a tumor on your dog can be a very scary experience. What is it? Is it cancer?
Of course, you should have all lumps and bumps on your dog checked by your vet to make sure it’s not a dangerous tumor. The good news is, roughly 80-90% of tumors are benign, non-invasive tumors and will not spread.
What exactly is a tumor?
Any lump, growth, or swelling on a dog is defined as a tumor. There are many different types of tumors, and tumors have many different causes.
Common Dog Cancer Overview
Some types of cancer show up more frequently than others in dogs. Below is information on the most common types of dog cancer, pertinent information, and most popular treatments.
Skin tumors are the most common type of tumor and comprise almost 50% of the tumors found in dogs. Skin tumors can be benign or malignant. Benign tumors are non-invasive and do not spread. Malignant tumors spread and destroy surrounding tissues.
A lipoma is a benign tumor, often called a “fatty tumor.” Lipomas are conglomerations of fat below the skin. Lipomas do not cause pain and usually are not removed. The exception is lipomas occurring in a place where they impede the dog's movement in some way.
Cysts are noncancerous swellings caused by a blocked hair follicles.
Basal cell tumors resemble the moles that humans get. They are usually raised, hairless, and reddish in color. Basal tumors are sometimes malignant, but benign roughly 90% of the time. If malignant, basal cell tumors can spread to major organs and become fatal.
Mast cell tumors are the most serious tumors that develop in dogs. These tumors often first appear as bumps under the skin. Mast cell tumors can look and feel like lipomas and are often overlooked. Mast cell tumors are difficult to remove completely because they spread both locally and to internal organs. Mast cell tumors invade the spleen, bone, liver, and lymph nodes. If left untreated, mast cell tumors are often fatal.
Internal cancers are common in dogs like in humans. Some serious forms of dog cancers are breast cancer, throat cancer, lung cancer, testicular cancer, and bone cancer.
Lymphomas are types of blood cancers that develop in the lymphatic system. Lymphoma cancer cells invade and cause the destruction of normal, healthy tissues.
The lymph nodes are the most common areas affected by lymphoma, but it can grow anywhere in the body. The lymph node will swell and harden when the lymphocytes within it become cancerous. Malignant lymphocytes then travel through the lymphatic system to nearby lymph nodes. Soon the malignant lymphocytes affect all lymph nodes.
The universal symptoms displayed in all types of lymphoma are:
- Weight loss
- Anorexia (lack of appetite)
Blood tests performed on dogs with lymphoma often show:
- Low lymphocyte levels
- A high number of neutrophils
- A high number of monocytes
- A low number of platelets
- High liver enzymes
Veterinarians also use radiographs and ultrasounds to check the size of the lymph nodes and estimate cancer's status. Canine lymphomas are common in dogs and vary in their behavior. Some lymphoma cases progress rapidly and are acutely life-threatening. Others progress slowly with owners managing a chronic disease.
There is no real cure for lymphoma. But, there are several options for treatment that can bring your dog into remission.
Your dog’s lymphoma prognosis and life expectancy vary depending on the tumor location and cancer's progression The World Health Organization (WHO) organizes lymphoma into five stages based on degrees invasiveness and metastasis in humans. Veterinarians use the same stages when discussing lymphoma in dogs.
Dog Lymphoma Stages:
Stage I: Cancer affects a single lymph node.
Stage II: Regional lymphadenopathy – cancer presents only on one side of the diaphragm
Stage III: Generalized lymphadenopathy – enlargement of the lymph nodes
Stage IV: Enlargement of the liver and spleen, also called hepatosplenomegaly, with or without lymphadenopathy
Stage V: Bone marrow, central nervous system, or involvement of other extranodal sites.
When a dog has lymphoma, chemotherapy is usually the best treatment option.
The most common protocol is the UW CHOP protocol. The UW CHOP protocol has approximately a 90% response rate and usually provides dogs with 13-14 extra months of life. The UW CHOP protocol usually costs $4,000 to $6,000.
Another treatment is available that puts dogs into full remission. Treatment consists of a bone marrow transplant with total body radiation treatments. To qualify for treatment, the dog must already be in remission. The dog first undergoes chemotherapy to clear the lymphoma from the blood.
Then a vet gives a medication called Neupogen to drive healthy stem cells into the bloodstream. The vet then harvests the stem cells, and the dog is given total body radiation to kill all lymphoma cells. The combination procedure is so intense that a bone marrow transplant is done afterward, re-planting the healthy stem cells back into the bone marrow. During the procedure, the dog must be kept in isolation because it has no white blood cells.
The procedure requires 2-3 weeks of hospitalization. The average cost is $17,000 plus the cost of the chemotherapy treatment before the procedure.
Two other options are the single-agent Doxorubicin protocol and Prednisone. The single-agent Doxorubicin protocol offers a 60-80% response rate. Prednisone offers a 50% response rate in making the dog feel better.
Radiation is another option. Palliative radiation eases symptoms of obstruction, shrinks lymph nodes, and shrinks lesions to improve symptoms. Half-body radiation treats the dog’s body one half at a time, first from the middle up, then from the middle down.
If your dog has lymphoma, you will also need to make changes in his diet.
Dog Skin Cancer
Skin cancer is very common in dogs. Mast cell tumors are the most common. Skin cancer occurs more often in middle-aged to older dogs than young dogs. Skin cancers can both on top of the skin or under the skin.
Benign tumors usually grow very slowly, are non-painful, and move freely.
Malignant tumors usually grow rapidly, contain ulcers, don’t heal well, and are constantly oozing and bleeding.
Skin cancer usually appears as a lump or bump and may even look like a mole or a black spot on your dog’s skin. Sometimes the tumor is ulcerated, sometimes not. The skin surrounding the tumor may be red and itchy causing your dog to scratch and lick the affected area.
To examine your dog for skin cancer, separate the hair with your fingers and look closely at the skin. Skin cancer and benign tumors often look very much alike. You should have any unusual growth checked by your veterinarian as soon as you find it. You should perform skin checks at least once a month, especially if you find a growth.
Dog Skin Cancer Symptoms:
- Areas of color change
- Scaly or crusty lesions
- Tumors: new growths or a change in size and/or color of old growths
- Easily bleeding tumors
- Non-healing wounds
- Discharge from or swelling around nipple
- Discoloration or lumps under the tail
- Mouth masses or tissue that differs from surrounding areas
If you find any of the above, contact your vet immediately. If caught early enough, you can eradicate many types of dog skin cancer. You can compare what you see with online photos, images, and pictures. But, for a final diagnosis, you need a biopsy.
Sometimes dogs with skin cancer display systemic symptoms. These symptoms will vary depending on the tumor’s location and how much it has metastasized.
Signs of Systemic Involvement
- Loss of appetite
- Vomiting and/or bloody vomit
- Abdominal pain
- Dark or black feces
- Irregular heart rhythm
- Irregular blood pressure
- Labored breathing
- Bleeding disorders
- Delayed wound healing
- Enlarged lymph nodes
To diagnose, your a veterinarian either removes the tumor or takes a sample, sending the biopsy to a lab for analysis. If sent to a lab, the pathologist will label your dog’s tumor with a “grade” and your veterinarian will assign a “stage” to your dog’s cancer.
The grade describes how differentiated the cells are and how aggressive cancer appears to be.
Grade 1 tumors are cell differentiated and carry a good prognosis. Usually, no treatment is necessary after the tumor is surgically removed.
Grade 2 tumors are moderately differentiated and sometimes complicated. Often, it is difficult to predict the prognosis and treatment options.
Grade 3 tumors have the poorest prognosis. Luckily, Grade 3 tumors are the most uncommon in skin cancer.
The stage describes how much cancer has already spread.
Stage 1 describes a single tumor with no signs of spreading and clean margins.
Stage 2 and Stage 3 tumors display more signs of invasion, have unclean margins, and maybe multiple tumors.
Stage 4 tumors involve systemic metastasis and have a poor prognosis.
Dog skin cancer is usually treated with surgical removal. Other cancer therapies may be used in addition to surgery if the cancer has metastasized and become systemic.
Dog Bone Cancer
Dog bone cancer, also called osteosarcoma, is a very serious condition that can be fatal.Osteosarcoma is very aggressive. It begins in the bones and spreads to the lungs, brain, or any number of other vital organs. The most common starting point for bone cancer is the leg, particularly the larger leg bones.
Osteosarcoma starts in the leg 82% of the time. Cancer then often progresses to soft tissue areas or other bones like the mandible (jaw), spinal cord, skull, or pelvis. Dogs often experience pain as a result of these tumors. Pain is a major symptom of bone cancer. A dog with a tumor in the leg will develop a limp that comes on very slowly over a period of weeks.
Dogs that have Cranial Osteosarcoma may have mental issues or defects. A tumor in the jaw can cause trouble chewing, while a tumor in the spine can cause trouble walking or breathing. A pelvic tumor may lead to the dog having trouble using the restroom because the tumor is blocking feces excretion.
The prognosis for dogs with bone cancer varies depending on the type of cancer and how far along the cancer is. Untreated, dogs with bone cancer have a life expectancy of 1-4 months.
But, there are several treatment options that can prolong a dog’s lifespan. Amputation combined with other treatments often allows dogs to live 1-2 years longer than if left untreated. If your dog has bone cancer, you also need to make changes in his diet.
Complete the following action items, and you'll be well on your way down the path to better health for your pet!
- Learn more about how to help your dog fight cancer by downloading our free ebook "What Every Dog Owner Should Know About Cancer: An Arsenal of Medical, Holistic, and Alternative Options."
- Try a fish oil supplement.
- Try switching to a low-carb diet. Stop feeding kibble. Kibble is loaded with carbs and toxic processed ingredients. Try cooking for your dog. If you're not sure what to feed your dog, try our TCVM Food Therapy quiz.
- Always consult with your veterinarian before making changes to your dog's diet and exercise routine.