What do cancerous bumps on dogs look like

10 Signs of Cancer in Dogs

Cancer is a topic that no pet parent wants to think about. But the fact is that one in three dogs will eventually develop some form of cancer during their lifetime.

If caught early, roughly half of all canine cancers are treatable. Thats why its so important to learn the most common signs of cancer in dogs.

Just remember that many conditions, not just cancer, can cause similar clinical signs, and that the signs may vary depending on the type of cancer.

Identifying these symptoms is the first step, and the next step is to visit your veterinarian to make the correct diagnosis.

Signs Your Dog Has Cancer

Here are some of the most common signs of cancer in dogs and the types of cancer that cause them.

Unexplained Lumps and Bumps

Several forms of cancer can cause lumps or bumps on your dogs body, including a mammary gland tumor.

Mammary Gland Tumors in Dogs

This type of cancer occurs primarily in female dogs that arent spayed as well as those spayed after 2 years of age, although male and female dogs of any age and breed may develop mammary tumors.

Certain breeds, including Poodles and various spaniel dog breeds, have an increased risk.

This cancer usually begins as one or more nodules in the nipple area, which may become inflamed and swollen. Malignant mammary tumors tend to spread to nearby lymph nodes and mammary glands if left untreated.

Lipomas

Not all noticeable tumors are serious, however. Lipomas are common but benign fatty tumors that grow in the layer just beneath the skin.

These tumors most frequently occur in the trunk, armpit and groin areas, but they can also grow internally. It is not uncommon for elderly dogs to develop multiple lipomas, which feel like soft, moveable lumps under the skin.

While lipomas are not life-threatening, they can interfere with movement if they become large enough, and internal lipomas may compress internal organs.

Lameness

Osteosarcoma is the most common bone cancer in dogs. While tumors usually occur in the long bones of the limbs, osteosarcoma can affect any bone.

This bone cancer grows very quickly and frequently spreads to other areas of the body, especially lymph nodes, lungs and other bones. Because of its aggressive nature, osteosarcoma is usually detected after the cancer has already spread.

Dogs with osteosarcoma may appear to be in pain and walk with a limp, and the affected limb may be swollen.

Large and giant dog breeds have the highest risk of developing osteosarcoma.

Pigmented Sores

Darkly colored sores are a sign of melanoma, a cancer of the pigment-producing cells.

Melanomas in dogs tend to affect the mouth and lips, and they can also be found on their nail beds, footpads and eyes.

Specific signs will depend on where the tumor is located and may include a swollen paw, eye discharge or sores in the mouth.

Breeds with darkly pigmented oral tissues, such as the Chow Chows tongue, have an increased risk of developing melanoma.

Surgical removal can be difficult, as malignant melanoma tends to be locally invasive and spreads to deeper tissues and bone.

Swollen Lymph Nodes

Several types of cancer can cause lymph nodes to feel more prominent.

Lymphoma is a common malignant cancer that accounts for up to 20% of all canine tumor cases.

This cancer affects the lymphocyte, a type of white blood cell that plays an important role in immune function.

While most lymphoma cases begin in the lymph nodes, lymphoid tissues in the visceral organs, skin and bone marrow can also be affected.

Lymphoma can affect dogs of all ages and breeds, but Golden Retrievers and Boxers are among the most overrepresented pure breeds.

Swollen lymph nodes in the neck, knee and armpit regions are typically the first to be noticed.

Several types of canine cancers can also spread locally to nearby lymph nodes, causing them to enlarge. These include melanoma, osteosarcoma and mammary gland tumors.

Wounds That Wont Heal

A particularly aggressive form of cancer known as the mast cell tumor, may present as a skin lesion that just wont resolve.

This cancer affects mast cells, which are immune cells involved in allergic and inflammatory reactions. These cells are located throughout the body, but tumors tend to concentrate in the vessels and nerves near the skin, mouth and nose.

Less commonly, the gastrointestinal, respiratory and urinary systems may be targeted.

Abnormal growth of these cells causes an uncontrolled release of histamine, irritating the area surrounding the tumor.

Mast cell tumors are most common in older, purebred dogs, including the Boxer, Boston Terrier, Bulldog and Schnauzer.

Gastrointestinal Problems

The massive release of histamine associated with mast cell tumors can also cause significant problems with the gastrointestinal system, leading to stomach ulcers, vomiting and diarrhea.

Less dramatic signs of GI upset, such as decreased appetite, may occur from several other forms of cancer, including osteosarcoma and lymphoma.

Sudden Weakness or Collapse

While weakness can arise from a number of factors, sudden collapse is an alarming but common symptom of hemangiosarcoma, a cancer of the cells lining the blood vessels.

Hemangiosarcoma is a rapidly spreading form of malignant cancer that most frequently targets the heart, skin, spleen and liver.

This form of cancer is most common in the German Shepherd, Golden Retriever and other large breeds.

Since dogs usually show only mild warning signs, cases of hemangiosarcoma may not be detected until the cancer has reached an advanced stage.

Unfortunately, one of the most common initial signs of hemangiosarcoma involves sudden collapse due to massive internal bleeding, usually from a ruptured spleen.

Labored Breathing

Several of the canine cancers mentioned above are capable of spreading to the lungs, where they may cause respiratory distress.

Melanoma, hemangiosarcoma, mast cell tumor and osteosarcoma can all cause labored breathing and coughing with metastasis.

Unexplained Weight Loss

Weight loss that has no apparent cause may be a side effect of cancer, particularly with hemangiosarcoma, lymphoma and osteosarcoma.

Weight loss typically occurs because of the metabolic demands of the tumor, or because your dog is in pain and discomfort, resulting in anorexia and decreased activity.

Dogs with oral melanoma may find eating and swallowing to be difficult, resulting in weight loss.

Lethargy

While a variety of issues can cause lethargy, cancer can cause increased sleep and a reluctance to exercise and play.

Specific cancers that are frequently associated with lethargy include lymphoma and osteosarcoma.

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Dog Skin Cancer: Types, Symptoms, and Treatment

The word cancer instills fear into the heart of every dog owner, but not all growths are cancerous. The most common growth found on dogs are lipomas, which are fat cells. Also commonly found on dogs are sebaceous cysts, which can become cancerous. If your veterinarian has diagnosed your dog with skin cancer, or if you are concerned that your dog might have a cancerous skin tumor or lump, it is understandable to feel worried and fearful.

Your veterinarian is your best resource to help you through any questions you may have about your dogs health and skin issues. However, here is some information you need to know about skin cancer in dogs to help you understand your dogs possible condition.

Can Dogs Get Skin Cancer?

Dogs can get skin cancer, just like we can. In fact, skin tumors are the most commonly diagnosed type of tumor in dogs. This is partly because skin tumors are easier to see with the naked eye than other types of tumors, and partly because the skin is exposed to more of the environmental factors that can cause tumors, such as chemicals, viruses, and solar radiation, then your dogs internal structures. Luckily, this also means that you and your veterinarian have a better chance of catching your dogs cancer before it progresses past available treatment options.

Causes of Skin Cancer in Dogs

Skin cancer can have a variety of causes. Just like with people, genetics play a large role in which dogs are more likely to get skin cancer. In fact, it is believed that genetics are the number one factor in the risk of a dog getting skin cancer. Triggers that may lead to a dog developing skin cancer include too much exposure to the sun, chemicals in the environment, hormonal abnormalities, and certain types of viruses.

Types of Skin Cancer in Dogs

There are several different types of skin cancer in dogs, just like there are several different layers of the skin. Each layer and skin component can develop distinct tumors, some of which may turn out to be cancerous.

Some of the more common types of skin cancer in dogs are:

• Malignant melanoma
• Mast cell tumors
• Squamous cell carcinoma
• Histiocytic cell tumors
• Fibrosarcoma

Malignant Melanoma

Melanomas can be either malignant or benign. These tumors are often dark-pigmented or can lack pigment. While benign melanomas are more common, malignant melanomas are a serious concern, as they grow quickly and have a high risk of metastasis (spreading to other organs).

Malignant melanomas are most commonly found on the lips, mouth, and nail beds. According to some researchers, the head, neck and scrotum areas are also moderately predisposed to skin cancer. Certain breeds, for example Miniature and Standard Schnauzers and Scottish Terriers, are at an increased risk, and males appear to be affected more than females.

Malignant melanomas look like raised lumps, often ulcerated, and can also look like gray or pink lumps in the mouth. Nail bed malignant melanomas, on the other hand, show up as toe swelling and possibly even loss of the toenail itself and destruction of underlying bone. Nail bed and footbed tumors often develop a secondary infection, leading to a misdiagnosis. These types of tumors usually metastasize to other parts of the body, decreasing the chances for a good outcome.

Mast Cell Tumors

Mast cell tumors are the most common types of skin cancer tumors. Mast cells release histamine, which is the chemical that causes some of the symptoms of allergic reactions in dogs, like irritation and itching. Mast cell tumors are cancer of these cells, and they can grow anywhere on your dogs skin, as well as in internal organs. The most common sites for mast cell tumors are the limbs, lower abdomen, and chest. About of mast cell tumors are found on dogs limbs.

Boxers, Pugs, Rhodesian Ridgebacks, Boston Terriers and older mixed breed dogs seem particularly susceptible to mast cell tumors, which most commonly affect dogs ages 8-to-10 years old. This cancer can be difficult to deal with, and your dog could have symptoms associated with toxins released from malignant mast cells, such as stomach ulcers, resulting from histamine release.

Squamous Cell Carcinoma

Skin squamous cell carcinoma is the most commonly diagnosed carcinoma of the skin, and primarily affects older dogs, especially Bloodhounds, Basset Hounds, and Standard Poodles. These tumors typically show up on the head, lower legs, rear, and abdomen, and appear as raised patches or lumps that are firm to the touch.

Exposure to the sun can be a cause of squamous cell carcinoma, but according to the National Canine Cancer Foundation, In dogs, the theory of exposure to sun is less obvious. It is believed that there may be some association with papilloma virus.

These tumors usually appear on your dogs abdomen, which is the area least protected from the sun by hair.

Histiocytic Cell Tumors

Histiocytic cells are a type of skin cell. When these cells proliferate into tumors, they are classified as histiocytic cell tumors.

These types of tumors are relatively common and typically affect dogs under 3 years old, especially Scottish Terriers, Bulldogs, Greyhounds, Boxers, Boston Terriers, and Chinese Shar-Pei.

There are three types of histiocytic cell tumors: histiocytomas, which are the most common; systemic histiocytosis, which mainly affects Bernese Mountain Dogs; and malignant histiocytosis, which also mainly affects Bernese Mountain Dogs and first shows up in the internal organs.

Fibrosarcoma

Fibrosarcoma and spindle cell tumors originate in the connective tissues of the skin and beneath the skin. These tumors can have a varied appearance, and while they are typically slow growing, they do tend to recur after surgical removal. Luckily, this type of tumor rarely metastasizes.

Fibrosarcoma usually affects dogs when they are middle-aged or older, with an average age of 10 years. Sometimes, an aggressive type of fibrosarcoma can affect young dogs. Your veterinarian will send off a sample of the tumor to a pathologist to determine whether or not the tumor is a low- or high-grade tumor, a classification that refers to the rate of cell division. This will help them give your dog an accurate prognosis and determine the best course of treatment.

This type of tumor is often found on the limbs. In addition to invading nearby structures, sometimes impeding their function, the tumors can also bleed, ulcerate, and become infected.

Symptoms of Skin Cancer in Dogs

The symptoms of skin cancer vary depending on the cancer, but in general, the best thing you can do to catch skin cancer early is to keep an eye on any strange lumps or bumps on your dogs body, especially as he ages.

Not all skin tumors are cancerous, and some, like skin tags, are usually benign sebaceous cysts or lipomas. However, if you discover an unusual lump or area of discoloration, play it safe and contact your veterinarian. Changes in the size, shape, color or ulceration of any growth or lump are also a cause for concern.

Diagnosing Skin Cancer in Dogs

Dog skin cancer is diagnosed by examining the cells of the skin tumor or lesion. Your veterinarian may perform a procedure called a fine needle aspiration, which takes a small sample of cells, or a biopsy, which removes a small portion of the tumor tissue or lesion by surgical incision. These samples are usually sent away to pathology for evaluation in order to obtain an accurate diagnosis.

Skin Cancer Treatment Options

A diagnosis of cancer for your dog is scary. Many types of skin cancer are treatable if caught early on, but it is understandable to feel worried.

Your dogs prognosis and treatment options will depend on a few factors, including the type of tumor, the location of the tumor, and the stage of the cancer.

Some skin tumors can be removed surgically to great effect. Others may require additional steps, such as radiation or chemotherapy.

Some types of cancer, for example malignant melanomas, are resistant to radiation therapy, while others, such as mast cell tumors, are more sensitive. Your veterinarian may refer you to a veterinarian oncologist when you have a cancer diagnosis. Veterinary oncologists have advanced training in cancer treatment.

Preventing Skin Cancer in Dogs

Some types of diseases are preventable, while others are not. As in humans, many cancers are the result of a genetic predisposition. In other cases, cancer is the result of a variety of factors coming together in an unlucky configuration, but there are a few things you can do to lower your dogs risk.

The risk factor most in your control is exposure to sunlight. If you have a light-skinned, short-haired dog breed, limiting your dogs exposure to direct sunlight, especially during the peak daylight hours, may help lower his risk of skin cancer.

The most important thing you can do to help your dog avoid skin cancer, however, is to familiarize yourself with all your dogs lumps, bumps, and rashes, perhaps during your daily grooming routine, and consult your veterinarian if you notice anything suspicious.