Dogs tend to be afflicted with the same types of cancers that affect people. Lymphoma in dogs mimics the lymphomas in people. Osteosarcoma in dogs also closely resembles the osteosarcoma in teenagers in its skeletal location and aggressiveness. Many other types of cancers also show similarities between dogs and humans
Although many breeds of dogs can potentially get cancer, there are a certain breeds that are more prone to cancers than others. The following breeds are most prone to cancer: Rottweiler, Bernese Mountain Dog, Bouvier des Flandres, German Shepherd, Great Dane, Labrador Retriever, Bichon Frise, Boxer and Golden Retriever.
Among the most common cancers in dogs are lymphoma, hemangiosarcoma, osteosarcoma, mast cell tumors, melanoma, squamous cell carcinoma, mammary carcinoma, apocrine gland carcinoma, transitional cell carcinoma and soft tissue sarcoma.
Some of the cancer treatments available to dogs include surgery, chemotherapy, radiation therapy, electrocautery and cryosurgery. Depending on the type of cancer and the location of the tumor, one or more of these treatments may be used to treat cancer in dogs.
Although these options are all available for canine cancer treatment, they can be very expensive. For example, surgery that requires deep tumor removal in dogs can cost more than $1,500 and radiation therapy for the cancer can range from $2,000 to $6,000, or even more, depending on the type of radiation therapy.
Despite the availability of these cancer treatments for dogs, many treatments fail to eradicate the cancers in dogs and ultimately fail to save the dog’s life.
Dogs are starting to live longer due to the proper care provided by most pet owners. Autopsies done on 2,000 dogs show that 23% of all dogs, regardless of age, and 45% of dogs 10 years of age or older died of cancer. So it is crucial for research to focus on delaying the onset of cancers in dogs because the chance of getting cancer significantly increases as the dog gets older.
Dietary Factors and Supplements
While there are options to treat cancers in dogs, such as chemotherapy or surgery, they can be expensive and have some side effects. Delaying the onset of cancer is a better approach.
There are multiple ways as to delay the onset of neoplasia. While there is this possible correlation, there are some supplements that can be added to a canine’s diet to help suspend the onset of cancer.
About 175 Scottish terriers were studied to determine if vegetable consumption could reduce the possibility of transitional cell carcinoma of the urinary bladder. The results revealed that consumption of green leafy vegetables and yellow-orange vegetables can lower the risk of TCC in the studied terriers.
Another dietary factor that can affect the probability of cancer is red meat intake. Another study found that the dogs who had an intake of homemade meals were shown to have a higher incidence of tumors and dysplasias compared to dogs who had an intake of commercial foods.
Another supplement that could be added to a dog’s diet is Vitamin D. According to the findings of another study, Vitamin D regulates certain cell functions which would be involved in the development of cancer.
With all these studies in mind, it may be important to consider a dog’s diet in determining the probability of canines developing some form of cancer.
However, there are some more practical dietary supplements that people can give to their dogs. Carrots, for example, are not only a vegetable that can be given to a dog, but they may have certain compounds that lower the risk of cancer known as phytochemicals.
A good example of a phytochemical would be beta-carotene, which is found in most vegetables. In fact, there is a study in mice that shows beta carotene did in fact inhibit mammary tumor growth. In a epidemiological study, it was seen that people with low beta carotene concentrations had a higher risk of stomach and lung cancer.
One group of interest would be carotenoids, of which about 600 different kinds have been discovered. The basic idea of carotenoids lowering the risk of cancer is that they are antioxidants, which delay the damage done to DNA caused by oxidative stress which increases the risk of cancer.
A study of antioxidant intake and lung cancer in middle-aged women revealed that carrot intake significantly reduced the possibility of lung cancer.
So there are many dietary factors that can increase or decrease the risk of cancer. With carrots, there is some evidence as they could decrease the risk of cancer, but also there is evidence that certain compounds in carrots may be the reason.
Exercise, whether it dogs or humans, is a well known way of maintaining a good overall health and there may be links between obesity and probability of cancer.
One study of the prevalence of disease in canines with different body condition scores found that, in adult dogs, the prevalence of neoplasia was higher in obese canines than it was in normal-weight canines. A similar study revealed that there is a higher prevalence of mammary tumors in canines diagnosed with obesity at 1 year of age.
Obesity in dogs is usually measured by what it known as a body conditioning score (BCS), which determines the distribution of body fat in the body. The BCS is usually on a scale from 1 to 5 with around 2.5 to 3 being normal weight.
Exercise helps to maintain normal bodily functions, such as energy balance and regulation of hormones. In fact, exercise reduces the risk of many other diseases including cancer. Exercise, along with diet and behavioral management, helps to manage an animal’s weight.
A study of human obesity and potential links to cancer noted that if the trends observed in the study were applied solely to the United States, 14% of all cancer-related deaths in men and 20% of all cancer-related deaths in women would be attributable to obesity.
While it has been noted that there is some kind of trend regarding an increased risk of cancer with obesity, it should be considered what can exercise do. Physical activity can lower the risk of cancer as it regulates body weight.
Another study of the relation between physical activity and the risk of human breast cancer observed that with increased physical activity, the risk of breast cancer decreased.
An analysis of the link between exercise and prostate cancer in males revealed that the average risk reduction was between 10% and 30%. Exercise does not only reduce the risk of breast cancer in women, but of prostate cancer in men as well.
Exercise is a preferable way to not only maintain body health, but also to lower the possibility of cancer. However, exercise will not be the only way to fight obesity and lower the risk. Along with dietary and behavioral control, exercise will help maintain a healthy weight in dogs. With the help of BCS, people can determine if their animal is obese or not.
Water is an essential part of our lives, as well as our pets’ lives. Although it may seem to be the least suspected source of carcinogens, many studies indicate the presence of harmful substances in tap water. As many households in the U.S. use tap water for drinking, they also use tap water as a drinking source for their pets.
Before tap water reaches the households, water companies must disinfect it to make it safer for people and their pets to use. One common method used to disinfect tap water is chlorine.
However, more and more treatment plants are using chloramine as a disinfectant instead. Chloramine has the following properties that make it ultimately more harmful to our health and our pet’s health:
- Chloramine stays in the water longer than chlorine, and is more difficult to remove.
- Chloramine combines with organic matter in water supplies to create toxic byproducts.
- Its vapors can accumulate indoors and concentrate in an enclosed area.
Some of the chemical byproducts that result from chloramine’s presence in tap water are trihalomethanes (THM), volatile organic compounds and haloacetic acids.
Volatile organic compounds are various substances from different sources, including chlorination and fuel. They come from a wide variety of sources and ultimately make their way into our drinking water, ultimately increasing the risk for many health problems for us and our pets.
Many of the volatile organic compounds in tap water are carcinogenic. Carbon tetrachloride, for example, ends up in tap water due to chlorination and has carcinogenic properties and it increases the risk of liver cancer.
According to NJ department of health, other carcinogenic compounds that can end up in tap water include trichloroethylene, tetrachloroethylene, methylene chloride, vinyl chloride, and 1,2-dichloroethane.
Volatile organic compounds from chlorinated solvents originate from home septic tanks, municipal landfills, hazardous waste dumps and industrial facilities. Improperly discarded volatile organic compounds can easily end up in the tap water, ultimately increasing your dog’s chance of acquiring cancer.
Trihalomethanes are four compounds (Trichloromethane, Dibromochloromethane, Bromodichloromethane and Tribromomethane) that end up in tap water due to chlorine reacting with organic and inorganic matter in water.
Trihalomethanes can cause bladder cancer and many other health problems, including the production of free radicals in the body, which ultimately increases the chance of developing cancerous cells’.
Haloacetic acids also end up in tap water due to chlorination of water and they have been classified as carcinogens. Although the effects of carcinogenic substances in tap water may not seem apparent, the prolonged exposure pet owners and their pets get to these carcinogens can ultimately increase the chance of getting liver cancer and bladder cancer. Therefore, we must find a solution to reduce the exposure to these carcinogens in tap water.
An effective method for removing these dangerous compounds from drinking water is carbon filtering. Carbon filters purify water by allowing the water to pass through the activated carbon, which is essentially charcoal crushed into powder.
Carbon filters work well due to the following properties of carbon. Carbon has a high affinity for wide variety of substances and carbon in filters has high surface area to allow efficient filtering.
Carbon filters can remove the following from tap water: chlorine, benzene, radon, trihalomethanes and volatile organic compounds. As carbon filtration can efficiently remove many carcinogens from tap water and is a relatively cheap method of purifying tap water, it is a feasible solution for reducing your dog’s exposure to cancer-causing compounds in their drinking water.
Spaying and Neutering
One of the common cancer types in dogs is mammary gland tumors. In fact, female dogs have three times the risk of developing breast tumor compared to the risk of developing breast tumor in human females. Although the exact cause of mammary gland tumors is unknown, it can be inferred that the tumors arise due to genetic and hormonal factors.
The result of the cancer is a slow-growing single mass or multiple masses in the mammary glands of dogs that can ultimately become malignant if left untreated for an extended period of time. So it is imperative that pet owners take action to delay or prevent mammary gland tumor in their dogs.
In dogs, the chance of developing mammary gland tumors increases as the dog gets older. The risk of developing mammary tumors in unspayed female dogs is 26%.
Evidently, most of the breast tumors in dogs occur when they are 6 years of age, however the average age for dogs is 10 years. So there is a significant chance that many of our pets can acquire mammary tumors sometime during their life. One way to reduce the chances of mammary gland tumor in your dog is to neuter the dog at an early age.
The procedure of spaying, also referred to as ovariohysterectomy, involves removal of the ovaries and uterus while the dog is under anesthesia. The procedure, usually a single day event, involves incisions in the abdomen in order to remove the ovaries and uterus. The recovery takes approximately a week.
In addition to reducing the chances of getting mammary cancer, spaying your dog also includes the following benefits: dogs are safer because they do not need to roam to look for a mate, spayed dogs do not develop a uterine infection called Pyometra and female dogs do not have bloody discharge during Estrus (term used to refer to time in reproductive cycle when the female becomes receptive to mating with males).
Spaying your dog protects her against breast cancer and the protective effect of spaying is found to be biggest when the procedure is done when the dog was younger than 2 – 2.5 years of age.
The following data, from a study done in Alameda County, California, shows the variation in chances of dogs getting mammary tumor depending on time of spaying:
|Spaying:||Chance of Getting Mammary Tumor|
|Prior to 1st estrous cycle||0.005|
|Between 1st and 2nd estrous cycle||0.08|
|After 2 or more estrous cycles||0.26|
Estrous cycles, which are physiological changes caused by reproductive hormones, start in female dogs after they reach puberty. Although the average age for a dog’s reaching the puberty stage is approximately 6 months, the actual age varies according to the size of the dog, with smaller dog breeds reaching puberty earlier than 6 months while larger dog breeds can take up to 2 years to reach puberty.
So it is essential for pet owners to spay their dog relatively early, particularly if it is a small breed. Spaying early may save the dog from acquiring mammary gland cancer in the future, ultimately allowing her to live healthier and longer and saving the pet owner thousands of dollars that would otherwise be spent on cancer treatment.
Image credit: Wikimedia.