Wooftales » Blog Archiv » Thick Green Lawns and Canine Malignant Lymphoma

By Dr. Karen Becker, DVM

This is the time of year when many dog owners get their pets outside to enjoy the sunshine and lush greenery.

But according to a study published earlier in the year in the journal Environmental Research, a romp across the lawn might actually be dangerous to your pet’s health.

The study, conducted over a six year period at the Foster Hospital for Small Animals at Tufts University’s Cummings School of Veterinary Medicine, showed that exposure to lawn pesticides – specifically those applied by professional lawn care companies – raised the risk of canine malignant lymphoma (CML) by as much as 70 percent.

According to The Merck Veterinary Manual:

Canine malignant lymphoma is a progressive, fatal disease caused by the malignant clonal expansion of lymphoid cells. Although lymphoid cell neoplastic transformation is not restricted to specific anatomic compartments, lymphoma most commonly arises from organized lymphoid tissues including the bone marrow, thymus, lymph nodes, and spleen. In addition to these primary and secondary lymphoid organs, common extranodal sites include the skin, eye, CNS, testis, and bone. Lymphoma is reported to be the most common hematopoietic neoplasm in dogs, with an incidence reported to approach 0.1% in susceptible, older dogs. Despite the prevalence of malignant lymphoma, its etiology remains poorly characterized. Hypothesized etiologies include retroviral infection, environmental contamination with phenoxyacetic acid herbicides, magnetic field exposure, chromosomal abnormalities, and immune dysfunction.

Dogs at Risk for Canine Malignant Lymphoma

From the published study, dogs at highest risk for acquiring CML were:

Over 50 pounds

Living in homes where pesticides and herbicides were professionally applied

Living in homes where owners used lawn care products containing insect growth regulators (insect growth regulators are chemical killing agents)

The study collected data using a 10-page questionnaire mailed to owners whose dogs were patients at Foster Hospital. Unfortunately, the study results do not name the lawn care or pesticide products used, or specific chemical ingredients in the products. It also doesn’t address quantities of chemicals used or length of exposure.

Also absent from the study was mention of genetic factors that might impact which dogs acquire CML. The study dogs were only identified as purebred or mixed breed, with no consideration given to the fact that certain breeds are at increased risk for developing CML. Those breeds include the Airedale, Basset hound, boxer, bulldog, bullmastiff, golden retriever, and the Saint Bernard.

Dogs and Thick Green Lawns

Whereas people have the choice to stay off chemically-treated grass, your dog doesn’t have that option – nor does she have the capacity to understand the potential dangers of rolling around in herbicide and pesticide residue.

People usually wear clothes and shoes outside – dogs don’t. And unlike people, dogs don’t change their fur or foot pads every day and throw the dirty stuff in the washing machine. So whatever collects on their feet and fur outdoors stays there until the next time they get a bath.

Most dogs, given the opportunity to play on thick green grass, will not only run across it, they’ll roll on it, dig around in it, sniff at it endlessly — even snack on it. So it’s easy to envision how normal canine behavior turns risky when your dog’s outdoor environment has been doused in potentially toxic chemicals.

Playing It Safe

Given the Foster Hospital study results, I would certainly recommend dog owners not allow their pets to be exposed to chemical lawn treatments. Specifically:

• Don’t apply pesticides to your yard, and if you use a lawn care service, don’t allow them to use them, either.


• Avoid lawn care and other gardening products that contain insect growth regulators (IGRs). (And be aware that the chemical pyriproxyfen, an IGR, is used in certain flea/tick spot-on treatments.)


• Don’t allow your dog access to any lawn unless you can confirm no pesticides have been used.

If you think your pet has rolled around on chemically treated grass, my recommendation is to bathe him as soon as possible. If you’ve walked your dog in a suspect grassy area, giving him a foot soak as soon as you get home should flush away any chemical residue that may be clinging to his feet and lower legs.

Canine Malignant Lymphoma Treatment Options

Canine malignant lymphoma (also known as canine lymphosarcoma) refers to a tumor made up of lymphoid tissues. Approximately 5% to 7% of all tumors found in dogs are these types of tumors. Lymphoma in dogs is seen at a higher incidence in dogs between the ages of 5 and 12. Breeds were this problem is seen more often include Golden Retrievers, Scottish Terriers, German Shepherds, Fox Terriers, Cocker Spaniels and Boxers.

Canine Lymphoma Symptoms

Multiple symptoms are associated with lymphoma in dogs. The most pronounced symptom is enlarged lymph nodes (called peripheral lymphadenopathy). Other symptoms include

• Heart Problems (anterior mediastinal which is a mass near the heart)


• Skin and Skin Membrane issues (mucocutaneous) – early signs of disease include eye, nasal and oral skin lesions such as a large pink spot on the lower or upper lip.
  
  
  
  

  “Robin” was successfully treated for dog lymphoma through early owner detection of a large pink lesion on the lip. Early detection was key to fast recovery.Source: Cornell University College of Veterinary Medicine

  
  
  
  


• Renal Problems (mass near the kidneys)


• Eye Problems
  
  
  
  • Eye inflammation (anterior uveitis)
  
  
  • Puss in the eye (hypopyon)
  
  
  • Dog eye hemorrhage (bleeding)
  
  
  • White blood cells normally not seen in a dog eye (infiltrate)
  
  
  
  


• Spleen Problems


• Dog liver problems


• Bone Marrow problems

Diagnosis of Canine Malignant Lymphoma

Based on the presence of the aforementioned symptoms, your veterinarian will conduct additional tests including testing of cells taken from the body using a fast method. If lymphoma is thought to be present, then a biopsy (taking a tissue sample) will be performed. The cells taken will be checked for the presence of abnormal formations of cells called lymphocytes.

Your veterinarian will work to determine the stage or how developed the canine lymphoma has become. The stage will indicate the type of treatment that is needed. In order to determine the stage, your veterinarian will need x-rays of your dogs abdomen and chest (thorax). Blood tests will also be needed to get an estimate of platelets, calcium, and protein levels. In rare cases, dog lymphoma causes a condition called canine hypercalcemia, where there are abnormal levels of calcium in the dog blood.

Prognosis for Canine Malignant Lymphoma

It is difficult to determine how long a dog will live that is being treated for lymphoma as different research reports have a wide range of conclusions. In general, dogs who are diagnosed with stage 4 or 5 lymphoma, will not live as long as those that have stage 1, 2 or 3. Dogs that are diagnosed with hypercalcemia, also have shorter survival times.

Dogs that are not treated, tend to only live 6 weeks on average after diagnosis. If you decide not to use conventional treatments for lymphoma in dogs, you might want to try a supportive therapy such as C-Caps, as mentioned toward the bottom of this page.

Conventional Treatment For Canine Malignant Lymphoma

Chemotherapy is the most commonly selected treatment option for dog lymphoma, followed by immunotherapy (suppressing the way the immune system responds to the disease). Chemotherapy could extend a dogs live approximately 6 to 10 months, while maintaining the dog’s quality of life. Treatments are usually applied every 3 weeks using a medication called Adriamycin. 81% of dogs on this treatment protocol achieved complete remission or partial remission for 9 months. Remission refers to a state where the canine lymphoma symptoms are reduced or stop getting worse.

Approximately 90% of dogs will respond will to lymphoma therapy, making this one of the best forms of cancer to treat. Be aware that therapy can be expensive. Because of this, a lower cost treatment method, prednisone is sometimes used with other medications. Prednisone can help a dog live an additional 2 months with 1/3 of dogs going into complete remission, 1/3 achieving partial remission and 1/3 showing no response to the treatment.

Often a combination of treatment approaches are used with dogs started on Adriamycin, followed by a treatment approach called COP which is an acronym for three different medications (cyclophosphamide, Oncovin, prednisone). COP alone puts approximately 75% of dog lymphoma into remission. 20% of dogs will go into remission for 1 year with the COP approach.

When adriamycin is used with COP (called COPA), canine malignant lymphoma remission times tend to be longer ( 6 mo vs. 7 months). 84% of dogs will go into complete remission, 7% with partial dog lymphoma remission. 22% of dogs on the COPA protocol for lymphoma in dogs achieve remission for a year.

Canine Malignant Lymphoma Treatment Side Effects

Dogs tend to handle chemotherapy well and often do not get the ill feeling that is common in humans. Hair loss is rare and usually is only seen in Poodles, Schnauzers and Old English Sheepdogs or other dogs that need constant grooming. The most common canine chemotherapy symptom is whisker loss. Other symptoms include dog upset stomach, diarrhea, vomiting and appetite loss.

In rare cases (less than 10%), adriamycin can lead to heart problems.

Predisone also has potential side effects including increased thirst/drinking of water, frequent urination, panting and an increased appetite.

Holistic Treatment of Canine Malignant Lymphoma

In addition to the COPA approach mentioned above, a dog may benefit from a natural remedy as part of their diet during recovery. Natural remedies are not a cure for lymphoma in dogs, but can help strengthen healthy cells, boost the immune system, reduce the impact of symptoms and help speed toward recovery. The ingredients listed below in addition to the aforementioned properties can also help to boost energy levels and maintain a dog’s appetite during this critical time.

Homeopathic products such as C-Caps contain ingredients that have a growing body of clinical support:

• Huang Qi (Astragalus membranaceous): herbal remedy known to support the immune system. Researches are studying this product for its effect on immuno-supportive polysaccharides and other active ingredients useful in supporting a healthy immune system. (Wang DC. “Influence of Astragalus membranaceus (AM) polysaccharide FB on immunologic function of human periphery blood lymphocyte”. Zhonghua Zhong Liu Za Zhi 1989;11:180-183).


• Mistletoe (Viscum album): helpful to maintain normal blood pressure levels. Recent research showed a link between this element and the immune system (Hajto T, Hostanska K, Fischer J, Saller R. “Immunomodulatory effects of Viscum album agglutinin-I on natural immunity”. Department of Internal Medicine, University Hospital Zürich, Switzerland. PMID: 9179367).


• Purple Coneflower (Echinacea purpurea): thought to help the immune system with over 500 studies completed on this ingredient (Barrett BP, Brown RL, Locken K, et al. “Treatment of the common cold with unrefined Echinacea: a randomized, double-blind, placebo-controlled trial”. Ann Intern Med 2002; Dec 17, 137(12):939-946)


• Ashwagandha (Withania somnifera): helpful for the blood and the immune system ((Davis L, Kuttan G. “Immunomodulatory activity of Withania somnifera”. J Ethnopharmacol 2000; 71:193-200.)


• Milk Thistle (Sylibum marianus): contains silymarin, which is an anti-oxidant, which helps the liver function, the organ which helps cleanse the body of toxins (Pares A, Planas R, Torres M, et al. “Effects of silymarin in alcoholic patients with cirrhosis of the liver: results of a controlled, double-blind, randomized and multicenter trial.” J Hepatol 1998; 28(4):615-621.)(Benda L, Dittrich H, Ferenzi P, et al.”The influence of therapy with silymarin on the survival rate of patients with liver cirrhosis (author’s transl)”. Wien Klin Wochenschr 1980; 92(19):678-683.)


• Cat’s Claw (Uncaria tormentosa): ancient remedy use to boost the immune system and support cells in your dog’s body that are still healthy (Rizzi, R., Re, F., Bianchi, A., De, Feo, V, De Simone, F., Bianchi, L., and Stivala, L. A. “Mutagenic and antimutagenic activities of Uncaria tomentosa and its extracts.” J.Ethnopharmacol. 1993;38(1):63-77)

To learn more about canine malignant lymphoma and natural remedies that can complement specific treatments mentioned above such as chemotherapy, you can visit the C-Caps manufacturers site. Of course, consult your veterinarian before giving a dog that is undergoing treatment remedies of any kind. In general, natural remedies are safe to use and based on the available evidence, can be of some help.

Related Articles

Canine Cancer Remedies

References for Canine Malignant Lymphoma:

Canine Lymphoma: Protocols For 2004
Gregory K. Ogilvie, DVM, DACVIM (Internal Medicine, Oncology)
CVS Angel Care Cancer Center
San Marcos, CA, USA

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