LYMPHOMA
The following information is simply
informational. It's intent is not to replace the advice of a
veterinarian nor to assist you in making a diagnosis
of your pet. Please consult with your own veterinary physician for
confirmation of any diagnosis. Your pets life may depend on
it.
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OVERVIEW:*
Lymphosarcoma (lymphoma) is the third most common cancer
diagnosed in dogs. It is a cancer of lymphocytes (a type of blood
cell) and lymphoid tissues. Lymphoid tissue is normally present in
many places in the body including lymph nodes, spleen, liver,
gastrointestinal tract and bone marrow.
The average dog with lymphosarcoma is between 6-9 years although
dogs of any age can be affected. Certain breeds (Boxer, German
Shepherd, Golden Retrievers, Scotties, Westies and Pointers) may be
more likely to develop this type of cancer. Males and females are
equally at risk. In most cases, we cannot tell what causes
lymphosarcoma.
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TYPES
OF LYMPHOSARCOMA:*Lymphosarcoma can be
divided up into 5 different forms which depend upon the primary
(predominant) site of the tumor. They are EXTERNAL, GASTROINTESTINAL, MEDIASTINAL, SKIN AND BONE MARROW.
EXTERNAL:
The most common form is
involvement of one or more of the external lymph nodes. Some dogs
may not feel sick or may have only very mild signs such as tiredness
or decreased appetite. Other dogs may have more severe signs such as
weight loss, vomiting, diarrhea, excessive thirst or urination,
weakness or difficulty breathing. The severity of the signs depends
upon the extent of the tumor and on whether the cancer has caused
changes in organ function. In many cases, the only noticeable sign
is an enlargement of the lymph nodes under the neck, behind the
knees or in front of the shoulders. Other organs, such as the liver,
spleen and bone marrow can be involved as well.
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GASTROINTESTINAL:
A second form is involvement of
the gastrointestinal tract. Dogs with this type of lymphosarcoma may
have vomiting, diarrhea, weight loss or a decreased
appetite.
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MEDIASTINAL:
The mediastinum is a term used
for a special aggregation of lymphoid tissue in the chest. Dogs with
this type of lymphosarcoma often are seen because of difficulty
breathing or excessive urination/thirst.
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SKIN:
Lymphosarcoma can also start in
the skin. This is known as cutaneous lymphosarcoma. Dogs with
cutaneous lymphosarcoma can have flaky, scaly, reddened skin and be
itchy. They may also have lumps in the skin, which can ulcerate and
cause discomfort. The footpads and gums can also be involved. Other
organs such as lymph nodes, liver spleen and bone marrow are
variably involved.
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BONE
MARROW:
If the cancer were confined to
the bone marrow, we would call this leukemia. The signs that we see
in dogs are usually related to decreased numbers of normal cells
(such as red blood cells which carry oxygen, white blood cells that
fight infection and platelets that help with clotting) which are
made in the bone marrow. Anemia, infections and bleeding are common
problems.
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DIAGNOSIS/INITIAL
EVALUATION:*
A complete evaluation of a dog
suspected of having lymphosarcoma involves obtaining a biopsy or
aspirate of the affected tissues and a search for tumor in other
locations (this is what we call staging). A complete blood count
(CBC), a serum chemistry profile and urinalysis are always performed
and provide important information regarding the effects of the
cancer on body functions as well as the ability of the patient to
handle chemotherapy. An abdominal ultrasound (sonogram) allows us to
evaluate the liver, spleen, internal lymph nodes and intestinal
tract for possible tumor involvement. Chest x-rays allow us to look
for enlarged internal lymph nodes, lung involvement or an enlarged
mediastinum. A bone marrow aspirate allows us to look for
involvement of the bone marrow. Once we have these results, we can
then decide upon the best treatment for an individual
dog.
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TREATMENT:*
Chemotherapy is the
mainstay of treatment for lymphosarcoma. Lymphosarcoma is very
sensitive to chemotherapy and up to 80% of dogs treated will go into
remission. The definition of remission is the complete disappearance
of detectable cancer. A remission is NOT a cure but it does allow
your pet to experience a good quality of life. It is important to
remember this because chemotherapy should not discontinued when a
remission is achieved. The length of remission depends upon many
factors including the primary site, how sick an animal is at the
start of treatment and the extent of disease. For those dogs that
have the most common type (external lymph nodes enlargement), the
average remission time is usually around 8-10 months with an overall
survival time of about 1 year.
The exact drugs and
schedule will depend upon how aggressive the cancer is behaving, how
sick an animal is at the start of treatment and any abnormalities in
organ function (especially important are changes in liver and kidney
function). On a typical schedule, your dog will receive weekly
treatments for the first 4-6 months. Several different drugs
(L-asparaginase, vincristine, Cytoxan and Adriamycin) are alternated
in order to reduce the chance that the tumor cells will become
resistant and to reduce the risk of side effects. Some of the drugs
are given as an injection and some are given orally (this can be
done at home). If your dog remains in remission for 4-6 months, the
interval between treatments is lengthened to every two weeks. After
one year, treatments are given every three weeks for an additional 6
months. If a patient is still in remission at 1 1/2 years, treatment
is discontinued. Only 10-15% of dogs will reach the point where we
can consider discontinuing treatment.
If a patient comes out of remission, we can try to put
them back into remission using either new combinations of the same
drugs or different drugs. Unfortunately, the chances of obtaining a
second remission are lower and the risk of side effects may be
higher. However, there are some dogs that do respond and have extra
time.
Most dogs will tolerate their
chemotherapy well and have minimal side effects. Serious side
effects are only seen in 5-10% of the patients treated. These
include nausea, vomiting, and loss of appetite, diarrhea, extreme
tiredness or infection. Hair loss or slow hair growth may also occur
in certain instances. Adriamycin can cause damage to the heart
muscle if given multiple times, though most dogs do not receive
enough of this drug to be a concern. Cytoxan can cause irritation to
the bladder wall in a small percentage of dogs. If this occurs, you
will see changes in urination (blood in the urine, straining to
urinate, frequent urination).
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CLINICAL STAGING OF
LYMPHOMA:**
Stage I –
Involvement limited to a single lymph node, or lymphoid tissue in a
single organ (excluding bone marrow).
Stage II –
Involvement of many lymph nodes in regional area ( tonsils).
Stage III –
Generalized lymph node involvement.
Stage IV – Liver
and/or spleen involvement (±stage III).
Stage V –
Manifestations in the blood and involvement of bone marrow and/or
other organ systems (±stages I-IV).
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CURRENT CLINICAL TRIALS FOR
LYMPHOMA:
The Animal Cancer Center at Colorado State
University has the following ongoing clinical trial for
lymphoma:
Patient
Disease:
Canine
Lymphoma
Study Name:
Dietary Fatty Acid
Supplementation and Drug Resistance in Canine Lymphoma
Purpose of the study:
The purpose of this
study is to determine if supplementation with specific dietary fatty
acids can decrease lymphoma’s resistance to chemotherapy without
increasing side effects to the patient. The study will further
examine the role dietary supplementation with fatty acids plays in
improving the effectiveness of chemotherapy and prolonging a
patient’s response and survival time.
Patient Entry
Criteria:
In
general, these studies are available to qualifying patients living
within 100 miles of the Animal Cancer Center at Colorado Sate
University. Dogs with stage III/IV lymphoma are eligible. No steroid
or non-steroidal anti-inflammatory drugs are to be taken within
three weeks before the start of the study. The patient’s blood
values must indicate normal calcium values. The dog must be free of
pre-existing conditions that might prevent it from living a year.
Owner Responsibilities:
The client must
commit to preliminary evaluation which includes blood tests,
radiographs, bone marrow aspirate, removal of a diseased lymph node,
and a nuclear scan. For the nuclear scan, patients must spend the
night in the hospital to maintain compliance with Colorado Radiation
Safety Standards. Thereafter, the client must commit to administer
daily oral supplements, and to weekly chemotherapy appointments for
a nine (9) week course of therapy.
Financial Incentives:
Owner is
responsible for paying the first $350. The study will then pay for
the cost of treatment related to the study. For more information
regarding financial incentives, please contact our Consult
Coordinator at 970-297-4195.
Current Oncology Clinical Trials - UW-Madison School of Veterinary
Medicine -
Fall/Winter 2002-2003
Dogs with Newly Diagnosed Lymphoma
May be eligible to participate in a funded,
randomized clinical trial evaluating a combination of chemotherapy
and a novel tumor cell vaccine. Owners are responsible for the cost
of initial staging and chemotherapy, and then all costs associated
with the administration of vaccine are paid for by the study. After
the completion of chemotherapy, the study requires 8-10 VMTH visits
over a 3-month period. The owners receive a $500 VMTH credit toward
the cost of chemotherapy.
For more information, contact Drs. David Vail, Ilene Kurzman, or members of the
Oncology Service for additional information or to refer a case.
Dogs with Relapsed Lymphoma
May be eligible to participate in a funded,
randomized clinical trial evaluating an anti-angiogenic agent
combined with CCNU chemotherapy. Owners are responsible for the cost
of the initial re-staging, and then all costs (including
chemotherapy) associated with the study are paid for by the study.
This study requires weekly visits to the VMTH for the first 3 weeks,
and then visits every 21 days thereafter.
For more information, contact Drs. David Vail, Ilene Kurzman, or members of the
Oncology Service for additional information or to refer a case.
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CLINICAL TRIAL
RESULTS:***
1. J Am Vet Med Assoc
2002 Jun 15;220(12):1813-7
Evaluation of treatment with
doxorubicin and piroxicam or doxorubicin alone for multicentric
lymphoma in dogs.
Mutsaers AJ, Glickman NW, DeNicola DB,
Widmer WR, Bonney PL, Hahn KA, Knapp DW.
Department of Veterinary Clinical
Sciences, School of Veterinary Medicine, Purdue University, West
Lafayette, IN 47907, USA.
OBJECTIVE: To
evaluate the antitumor and toxic effects of treatment with
doxorubicin combined with piroxicam or doxorubicin alone for
multicentric lymphoma in dogs. DESIGN: Nonrandomized clinical trial.
ANIMALS: 75 dogs with multicentric lymphoma. PROCEDURE: 33 dogs were
treated with doxorubicin (30 mg/m2, IV, q 21 d, for 3 doses) and
piroxicam (0.3 mg/kg [0.14 mg/lb], PO, q 24 h); results were
compared with a historical control group of 42 dogs treated with
doxorubicin (30 mg/M2, IV, q 21 d, for 3 doses) alone. Results-The
percentages of dogs that had remission with doxorubicin-piroxicam
treatment (79%) or doxorubicin treatment alone (74%) were not
significantly different. Median duration of first remission was 130
days with doxorubicin-piroxicam and 147 days with doxorubicin alone;
these values were not significantly different. Severe toxicosis was
observed in 22% of dogs treated with doxorubicin-piroxicam and 17%
of dogs treated with doxorubicin alone. CONCLUSIONS AND CLINICAL
RELEVANCE: Both treatment protocols were efficacious and well
tolerated. The doxorubicin-piroxicam treatment was no more effective
regarding response rate, remission duration, or survival duration,
compared with the control group treated with doxorubicin
alone.
Publication Types:
- Clinical Trial
- Controlled Clinical Trial
PMID: 12092954 [PubMed - indexed
for MEDLINE]
2.) Vet
Res Commun 2002 Jun;26(4):285-96
Alpha-fetoprotein in canine multicentric
lymphoma
Lechowski R, Jagielski
D, Hoffmann-Jagielska M, Zmudzka M, Winnicka A.
Department of Internal
Diseases and Clinic, Faculty of Veterinary Medicine, Agricultural
University of Warsaw, Poland.
The
concentrations of AFP were evaluated in the sera from groups of
healthy dogs and of dogs with multicentric lymphoma, before and
while receiving chemotherapy. The concentration of AFP was highest
in the affected dogs, especially during the fifth stage of lymphoma.
Chemotherapy caused a decrease in AFP serum concentration, during
both the induction and the maintenance phases of treatment, when
compared to the same animals before therapy. Determination of the
concentration of AFP in the serum may be an additional indicator in
the evaluation of the stage of lymphoma, and of value in assessing
the extent of neoplastic infiltration of the
liver.
PMID: 12184499 [PubMed -
indexed for MEDLINE]
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LINKS TO ADDITIONAL INFORMATION ON
LYMPHOMA: | 
