mostly affects the external lymph nodes. They may or may not involve other organs. But in a vast majority of cases it has been observed that lymphoma

Size: px

Start display at page:

Download "mostly affects the external lymph nodes. They may or may not involve other organs. But in a vast majority of cases it has been observed that lymphoma"

Elaine Clark
5 years ago
Views:

1 Lymphoma in dogs What is the prognosis for dogs with lymphoma?. lymphoma or lymphosarcoma is one of the most common neoplasms (tumor) in dogs. They usually originate in lymphoid tissues, like the lymph nodes, spleen, and bone marrow. However, they can arise in any tissues in the body. Lymphoma accounts for approximately 7-24% of all canine neoplasia (formation of a new tissue) and 83% of all canine hematopoietic (blood cells) malignancies. Lymphoma is generally seen in middle aged to older dogs (median age, 6-9 years). Breeds that are believed to have a higher incidence of lymphoma comprise Boxers, Bull Mastiffs, Basset Hounds, Saint Bernards, Scottish Terriers, Airedales and Bull dogs. Dogs with a lower risk include Dachshunds and Pomerians. Neutered females tend to have a better prognosis. 10 Ways to Stop Your Cat from Peeing Outside the Litter Box. Mechlorethamine (Mustargen) can be applied on the skin as an aqueous solution or an ointment base. The solution is prepared by mixing 10 mg of mechlorethamine with 50 ml of tap water. For preparing 900 mg of ointment, 90 mg of mechlorethamine is mixed with 10 ml of absolute alcohol and sufficient xipamide (Aquaphor). It is essential to remove hair before applying the ointment. Gloves must be used, since mechlorethamine is carcinogenic (cancer causing) and can cause contact hypersensitivity in humans. Other possible environmental factors include homes that have a high usage of other chemicals like paints and solvents. Dogs that live in industrial areas are believed to be at an increased risk of lymphoma. There is even some speculation that strong magnetic fields may increase the incidence of lymphoma in dogs, but there is currently no absolute proof. Stage I: Ailment restricted to a single lymph node. 2. Ask your vet for a referral to a board-certified oncologist. A term for a type of neoplasm that is made up of lymphoid tissue; these masses are usually malignant in nature. Stage V: Bone marrow or blood involvement and/or other organ besides liver, spleen and lymph nodes involved. When it comes to traveling in a car with your dog, safety should be paramount for you both. However, a recent study from Volvo Car USA found some surprising statistics. Multi centric lymphoma- Multicentric lymphoma

2 mostly affects the external lymph nodes. They may or may not involve other organs. But in a vast majority of cases it has been observed that lymphoma eventually invades the organs and the healthy tissues are replaced by the diseased ones. Death occurs mostly due to organ failure as the organ becomes dysfunctional under the impact of the disease. Treating other forms of lymphoma is often more difficult. Alimentary lymphoma, if concentrated in one area, can be treated effectively with surgery to remove the tumor, together with combination chemotherapy. However, if lymphoma is spread throughout the intestinal tract, the response to treatment is not as good and survival times are shorter (often less than 3 months). The use of combination chemotherapy with or without radiation can give dogs with mediastinal lymphoma considerable improvement in survival times and quality-of-life scores. Dogs with an abnormally high level of calcium in the blood, a condition often associated with mediastinal lymphoma, are also less likely to live for long. Lymphoma involving other extranodal sites, such as the skin, can be managed with surgery, radiation, and chemotherapy as appropriate; however, the disease often stops responding to treatment. Dogs with low-grade lymphoma tend to do well and with chemotherapy can survive longer than two years. New Set of Financial Education Tools Introduced by AVMA. Small structures that filter out the lymph and store lymphocytes. The topical products we use on ourselves and even our pets could cause big problems if accidentally ingested or administered incorrectly. Find information on animal health topics, written for the veterinary professional. There is also a variety of alternative holistic treatments available to help dogs fight lymphoma. These include nutrition supplements, homeopathy, and more. Holistic treatments can help slow or reverse the spread of the disease and can help dogs undergoing conventional chemotherapy treatments in the healing process. Weak immune systems have also been identified in dogs with lymphoma. While suppression of the immune system is a known risk factor for the development of lymphoma in humans, the link between immune suppression and lymphoma in dogs has not been clearly established UBM. All rights reserved. Reproduction in whole or in part is prohibited. Please send any technical comments or questions to our webmasters. Pet owners all want to know what caused their dog's cancer, Dr. Ettinger says. And the cause is multifactorial. Environmental causes, previous immunosuppression and genetics are all involved, but no direct cause has been established to date. Dilated Cardiomyopathy in Dogs Linked to Grain Free Diets. Stay informed with the latest information from OncoLink!. Are there any clinical

3 trials investigating new treatments for dogs with lymphoma?. Canine bone marrow transplantation for lymphoma is the replacement of irradiated bone marrow with normal stem cells after chemotherapy is concluded. It allows veterinary oncologists to treat lymphoma with the most aggressive chemotherapy possible. They can administer a dose of total body irradiation high enough to kill lymphoma cells that may be resistant to chemotherapy or residing in locations in the body where chemotherapy cannot reach. To learn more about this new treatment option, please visit the. Lymphoma is a diverse group of cancers that originate in lymphocytes - a type of white blood cell in the immune system. The commonly affected sites are lymph nodes, spleen and bone marrow, but lymphoma can occur in almost any tissue in the body where there is lymph tissue such as the gastrointestinal tract, eyes, central nervous system, bone, testes, bladder, heart, and nasal cavity. Lymphomas typically affect middle-aged dogs (6-18 years old), and certain breeds such as boxers, bull mastiffs, basset hounds, Saint Bernards, Scottish terriers, Airedales, and bulldogs appear to be at higher risk. Lymphoma can be classified into several categories: The Canine Lymphoma life expectancy data above are based on statistics for conventional canine lymphoma care (primarily one of the chemotherapy protocols), but there is generally only anecdotal evidence available for the life expectancy of a Canine Lymphoma dog treated with alternative "holistic" care (or with a combination of holistic and conventional care). Life expectancy for dogs who receive Prednisone alone. Inhalation of 5-aminolevulinic acid: a new technique for fluorescence detection. For more Canine Lymphoma support and for answers to questions about your dog's cancer care visit our member support forum at SYMPTOMS: Malignant tumors may present as a single lump, a mass, or multiple swellings in the tissues comprising the mammary glands. Most frequently these tumors occur in the glands situated closer to the rear legs. Compared to benign growths, malignant growths may grow rapidly, have irregular shape, feel "fixed" to the skin or underlying tissue, and/or become ulcerated. Malignant tumors may occur simultaneously with mastitis in lactating females and become apparent when symptoms of mastitis are resolved with antibiotic treatment. Inflammatory carcinoma, an extremely aggressive form of mammary cancer, is similar to mastitis in appearance but should be immediately suspected when its symptoms occur in a non-lactating female. This cancer presents as a mass that may involve several or a chain of the mammary glands. The effected area appears red, swollen, and warm to the touch. In fact, touching the area

4 results in obvious discomfort to the female. Hence this form of lymphosarcoma sometimes is called thymic lymphoma. We saw the holistic vet every three or four weeks, and he fine tuned Clondike's herbal mixture based upon his exam. While the effect of the herbs was too subtle to state with certainty that they helped with either the cancer or the chemo, they did noticeably reduce Clondike's episodes of night panting attacks. Our general practice vet was very supportive of our search for complementary medical advice and she frequently faxed lab results to the holistic vet to keep him up to date on Clondike's progress from a Western perspective. Although often caused by the leukemia virus, the cases we have experienced have occurred in FeLV negative Oriental Shorthairs, which have been strictly indoors in FeLV negative catteries. Since these cats are related we suspect a genetically inherited cause instead of viral. For example, a Madison Wisconsin Chemotherapy Protocol (the most commonly used Canine Lymphoma chemotherapy protocol), which combines 3 different types of chemotherapy plus Prednisone over a 6 month/25 week treatment plan, has an 80% 90% overall response rate with healthy stage 3 or stage 4 dogs, with b cell lymphoma, for a "median" response duration of 12 to 15 months. And as noted above, the vast majority of dogs diagnosed with Canine Lymphoma fit this healthy, stage 3 or stage 4, b cell lymphoma staging, which is why Canine Lymphoma is considered to be one of the most treatable and responsive cancers using current conventional treatments. (Remember, these are just statistics based on past results nobody can ever tell you how long YOUR particular dog will live under any of these circumstances):. Survey radiography (x-ray) is probably the most common diagnostic imaging tool utilized in veterinary oncology. In many instances, radiographs are adequate for identifying the presence of a definite tumor mass or alterations in 1) position 2) size 3) shape or 4) density of bones, soft tissues, and organs that may indicate the presence of a cancerous growth. In human medicine, use of conventional radiography for identifying the presence of lung metastases is equally effective as imaging with computed tomography (CT). For example dogs with stage 5 lymphoma (generally Lymphoma combined with some element of bone marrow cancer) the chance of remission is much less maybe 50% with modern conventional canine lymphoma treatments. disorders, and they usually occur as a result of the tumor causing alterations in the patient's energy metabolism. Therefore, effects may be seen at sites distant from the actual location of the tumor. Symptoms of paraneoplastic disorders include weight loss, low-grade fever, muscle-weakness and/or seizures,

5 lethargy, loss of appetite, diarrhea, skin rash, hair loss, and general arthritic-like symptoms. Usually, the "wait-and-see" method to diagnose such cancers is inappropriate since by the time these cancers actually become large enough to detect, they have already reached an advanced stage and are unlikely to respond favorably to treatment. Therefore, with these ellusive cancers, specialized diagnostic techniques such as laboratory screening tests and radiologic exams provide a means for earlier diagnosis and perhaps better long-term prognosis for treatment success. Definition While we understand how lymphomas form, we still do not understand why. There is growing evidence and much speculation that environmental factors such as exposure to pesticides (especially herbicide 2,3-D) (Read New York Times Article: Lawn Herbicide Called Cancer Risk for Dogs). A new study published in April 2012 finds that utilizing a chemical lawn service to achieve a lush lawn is likely causing malignant cancer in many pet dogs. In the study, researchers identified 263 dogs with biopsy-confirmed canine malignant lymphoma (CML), 240 dogs with benign tumors, and 230 dogs undergoing surgeries unrelated to cancer. Then, they asked the pet owners to complete a 10-page questionnaire. Scientists found that dogs with malignant lymphoma were 70 percent more likely to live in a home where professionally applied lawn pesticides had been used. of early stage lung cancer. R. Baumgartner et al., J Photochem. Photobiol. B., 36:169-74, Withrow Stephen J, and David M. Vail. Small Animal Clinical Oncology. St Louis: therapy for incompletely resected canine mast cell tumors. T. LaDue et al., Vet. Radiol. The prognosis for dogs with lymphoma will depend on the lymphoma subtype, location of the disease, how advanced it is and the overall health. Generally speaking, the earlier the diagnosis is made, the better. Without treatment, most dogs will die of the disease in 4-6 weeks. Fortunately, a high percentage of dogs have a good response to chemotherapy without major side effects. Dogs that respond to chemotherapy and achieve complete remission (absence of disease) usually remain free of symptoms and return to a very good quality of life. About 25% of dogs are long term survivors (longer than 2 years) and some are cured. Please join our Feline Lymphoma group, excellent support and all the great advice you'll ever need.:: Getting Started. But with appropriate treatment, many dogs will experience "remission" (essentially a temporary "cure") from the disease for an extended period of time ( on average, about 12 to 18 months, depending on the case and types of treatment used). For that reason, the primary goal of modern conventional Canine Lymphoma treatments is not to cure the patient, but to help the patient to go into remission for as long

6 of a period as possible. Stage 3 lymphoma is generalized in nature and involves several lymph nodes around the body. Symptoms This form of lymphoma comprises only a fraction of all cases of lymphosarcomas. It is typically characterized by enlargement of the cranial mediastinal lymph nodes, thymus, or both. Dogs suffering from mediastinal lymphoma encounter respiratory distress, polydipsia, polyuria, pitting edema of the head, necks and forelimbs. Among other alternative treatments, autologous vaccines combined with chemotherapy have been shown to have positive effects in dogs. A tumor vaccine extract using killed lymphoma cells combined with Freund's adjuvant (freund's adjuvant is an antigen. Stage II: Regional lymphadenopathy (restricted to one side of diaphragm). Stage III: Generalized lymphadenopathy (enlargement of lymph nodes). Prognosis- Dogs suffering from canine T- cell lymphoma were treated successfully with Isotretinoin for upto 13 months. Dogs treated with Doxil have been found to produce remissions in 40% cases. Although most of these were short-lived responses, remissions of 1 year or longer have occurred. Dogs treated with CCNU showed complete response and two of those responses were relatively durable (7 and 15 months). Dogs with diffuse T-cell lymphoma under the impact of combination chemotherapy with c over a wide range of ages and breeds. Males have a higher predilection compared to females. Treatment Alimentary lymphoma, if focal, can be treated effectively with surgical resection and combination chemotherapy. The involvement of local lymph nodes and liver is very common in this case. No standard protocol has been identified for the treatment of lymphoma. But, multiple-agent therapies appear to generate the most favorable results. Three types of protocols are of importance in treating lymphoma: the induction protocol, the maintenance protocol, and the rescue protocol (used when the patient comes out of remission). The combination of L-asparginase, vincristine, cyclophosphamide, and doxyrubicin is commonly used. Solitary lymphosarcomas are rare in dogs. But if the tumor is localized, it can be removed surgically. Stage 4 lymphoma manifested in the dog's spleen or liver. Generic causes- The etiology is largely unknown and likely multi factorial. Current investigations are going on to ascertain some definitive causes. Chromosomal aberrations (change in the normal structure of chromosomes) have been reported in canine lymphoma. Though the involvement of a retrovirus (any of a group of viruses, many of which cause tumor) in the pathogenesis (development of a diseased or morbid condition) of canine lymphoma has not been confirmed, certain viral particles with properties similar to retroviruses have been detected in the

7 short-term cultures of canine lymphoma tissue. Certain environmental factors are also believed to trigger the disease. A hospital based case control study of dogs indicated that owners in households that developed malignancy sprayed 24-D herbicides in their lawns. Dogs living in industrial areas are believed to be at an increased risk of lymphoma. Moreover, households where owners use more chemicals like paints and solvents, dogs have been found to be slightly predisposed. Weak immune system has also been identified in dogs with lymphoma. Although surgery may not be effective in most pets suffering from lymphoma, the vet will treat the dog with chemotherapy medication. Commonly administered chemotherapy drugs include prednisone, doxorubicin and cyclophosphamide. The drugs are available in both injection form and oral medications. Pets may also be treated at home with chemotherapy medication. However they require proper home care and attention. Medications should be administered on time, according to vet instructions. It's important to understand that pets that enter remission may require a combination of other drugs when they come out of remission. Chemotherapy is mostly scheduled on a weekly basis with intervals in between. Most pets in Stage 3 lymphoma, treated with chemotherapy survive for a minimum of one year. Stage I: Ailment restricted to a single lymph node. hemorrhage ), and ulceration, because these indications could be of anemia or thrombocytopenia (low blood platelet count) secondary to myelophthisis or immune mediated disease or may be evidence of a major organ failure. Abdominal palpation is also essential for it may reveal organomegaly, intestinal wall thickening, or mesenteric lymphadenopathy (swelling of the mesenteric nodes). Diagnostic techniques and clinical staging- The diagnostic techniques include fecal flotation, complete blood count (CBC), serum biochemical profile and urinanalysis. Ultrasonography is also very useful in this case. Lateral and ventrodorsal abdominal radiographs are taken to assess the liver and verify the source of the abdominal distension, and check for foreign bodies. Radiographs can also reveal large amounts of foreign bodies in the gastro intestinal tract. Dogs that suffer from lymphoma develop enlarged lymph nodes in specific parts of the body. Although some lymphomas can be felt by palpating the skin, others that grow internally can only be detected through radiographs and diagnostic tests. Other organs susceptible to lymphoma include the liver, gastrointestinal tract and bone marrow. During the diagnosis of canine lymphoma the vet will perform a complete blood count test along with biopsies or fine needle aspirate tests. This will enable the vet to determine the type and severity of

8 lymphoma present. Lymphomas are categorized into different stages according to the number of lymph nodes and organs involved. Learn More About the NCCF, our Mission and Canine Cancer. If reinduction fails or the dog does not respond, the use of so-called rescue agents or rescue protocols can be attempted. These are drugs that are not found in the standard chemotherapy protocol. They are kept in reserve for later use. The most common rescue protocol include single agent or combination use of actinomycin D, mitoxantrone, doxorubicin (if it was not part of the initial protocol), a doxorubicin/dacarbazine combination, lomustine, L- asparaginase, and the combination mechlorethamine, vincristine, procarbazine and prednisone. Approximately, 40-50% of dogs respond, but their median survival rate is 1.5 to 2.5 months. emulsified in mineral oil, used as an immunopotentiator [booster of the immune system ]) was injected in dogs after remission induction with combination chemotherapy. Treatment- The treatment of cutaneous lymphoma depends on the extent of the disease. Solitary lesions may be treated with surgical excision or radiation therapy. Fractionated radiotherapy has been associated with long term control. Diffuse non-t-cell lymphoma is best treated with combination chemotherapy. Retinoids, (chemical compounds related to Vitamin A) like isotretinoin (Accutane) and etretinate (Tegison) have yielded gratifying results in canine T-cell cutaneous lymphoma. In animals with anemia or evidence of bleeding, a reticulocyte (young red blood cells) count and coagulation studies may be indicated. If some dogs have a high total protein evidence or evidence of an increased globulin fraction (globulin is one of the two types of serum. Dogs with multicentric lymphoma mostly undergo chemotherapy. However, surgery can be carried out in a couple of cases where the disease is in its initial phase. In such instances, careful staging is important to rule out multicentric involvement. Sometimes splenectomy is recommended only if the disease is receding in other sites and if the splenic enlargement is caused by lymphoma that is not responsive to chemotherapy. It can also be considered as a treatment for hemolytic anemia (anemia due to destruction rather than underproduction of red blood cells) and persistent thrombocytopenia. Stage V: Bone marrow, CNS (Central Nervous System), or involvement.

Lymphoma (Lymphosarcoma) by Pamela A. Davol

Lymphoma (Lymphosarcoma) by Pamela A. Davol Cells derived from the bone marrow that mature and take part in cellular immune reactions are called lymphocytes. When lymphocytes undergo transformation and