Cancers like lymphoma and leukemia are closely linked together in that they affect the body in the same system, but do so in slightly different ways. That slight change in their impact on the body can completely alter the needed treatment to bring the dog into remission. Though the two cancers interact vastly differently with the cells of the body, their representation through symptoms in the body can be almost identical.
As we know, lymphoma is a cancer of the lymphocytes, either B- or T-Cells, in the immune system of the body. The mutation of a lymphoma cancerous cell starts to happen often in the lymph nodes.
Leukemia is a blood cancer, which means that it can affect any of the 3 types of cells in the blood. White blood cells, red blood cells, or platelets. The alteration of the cells often starts in the bone marrow, where blood cells start to develop from stem cells.¹
Leukemia develops when a cell starts to divide too quickly during the maturation process within the bone marrow. The complicated part is that if the cell that divides is a white blood cell, the symptoms of a lymphoma patient will be visible: swollen lymph nodes, abnormal cells in circulation, and similar changes in behavior. When leukemia affects the other blood cells it doesn’t cause many visible changes, and sometimes won’t even have symptoms early on, this kind of leukemia is found through regular blood tests.
Like lymphoma, leukemia also has two main categories for diagnosis, ALL: acute lymphoid leukemias, or CLL: Chronic lymphocytic leukemia. Both are treated differently and impact the body in different ways. CLL is the most common manifestation of leukemia in canines.²
Leukemia is a blood cancer that can either show symptoms the way lymphoma does, or be found through regular blood work checkups.
Properly identifying the cancerous cells is the most important factor in diagnosing leukemia, due to the interaction with the body being so similar to lymphoma. Like lymphoma, diagnosing leukemia needs to be done with live cells. The tests are similar and look for factors that would determine if a sample is a lymphoma B- or T-cell, or a case of ALL leukemia or CLL leukemia. The difference between those four affected cell types should direct treatment for the patient.
Tests for leukemia can include bone marrow cytology, molecular diagnosis by polymerase chain reaction (PCR) or immunophenotyping by flow cytometry. These three tests mark cells in a sample in different ways to identify the regularity and repetition of certain mutated cells. Each of these tests can be performed on samples of both blood and bone marrow as well as solid tissue biopsies.³
Performing these tests on bone marrow biopsy samples isn’t very helpful in diagnosing early-stage lymphoma. However, the bone marrow cytology tests are beneficial for leukemia patients because that is often the start of the cancerous mutation. If the patient has lymphoma, a bone marrow test will show a low level of cancerous cells in the marrow, but if it reaches over 20-30% that can be a positive sign that the patient has leukemia.
Diagnosing leukemia can be a difficult task for some newer vets because the outward impact it has on the body is so similar to lymphoma; there are more cases of misdiagnosis with leukemia and lymphoma than anyone would want. Luckily, some of the treatment methods overlap, so if an unfortunate case of misdiagnosis happens, there is still a high chance your pet is receiving necessary care.
Between the two kinds of leukemia, Chronic lymphocytic leukemia is the best diagnosis to receive. The average age of diagnosis for CLL is 10 to 12 years old, and in up to 50% of cases the diagnosis is often found through regular blood work as the patient doesn’t always show any symptoms of the cancer.
CLL progresses slowly enough that if a patient doesn’t have multiple conditions, treatment isn’t always necessary to keep the patient around. The average life expectancy after a diagnosis of CLL is one to three years after diagnosis, with a good quality of life.
When discussing Acute lymphocytic leukemia, the outcomes are not always so great. ALL is more aggressive than CLL and requires treatment early after the diagnosis. The average age a dog is diagnosed with ALL is 6 years old, and without treatment, their life expectancy can be as short as days or as long as a few weeks. With treatment, 30% of patients achieve remission that can last for a few months, and on occasion up to a year.⁴
Leukemia is almost exclusively treated with chemotherapy. Due to the cancer being in the bloodstream, a treatment that affects the full body is necessary.
Like with lymphoma, there are various drugs that are used in chemotherapy treatments for leukemia. Because they are adaptive diseases, more options available to treat the development are needed. The ones your pet will receive will be based on the kind of leukemia that they have. For Acute leukemia, the common drugs used in treatment are prednisone, vincristine, cyclophosphamide, L-Asparaginase, and doxorubicin. You might notice that several of these drugs are also incredibly effective in treating lymphoma. ALL can also be responsive to a CHOP protocol that is modified for efficacy in leukemia cases.⁵
Some of the drugs commonly used to treat CLL include prednisone, chlorambucil, and cyclophosphamide. There are also cases where a dog with CLL doesn’t need treatment right away because their symptoms are slight enough that they just need regular monitoring. Treatment too soon would be unnecessary.
ImpriMed has state-of-the-art labs that are able to help test for leukemia in more detail than some animal hospital labs. To test for leukemia we will run blood tests and perform a flow cytometer test, as well as a PARR test to find the most information about your pet’s leukemia and to verify that the diagnosis is for leukemia rather than for lymphoma.
After the tests are complete, ImpriMed uses the live cells from the sample to test different chemotherapy drug responses. This test, along with artificial intelligence, is able to identify the best treatment plan available for your pet’s individual, unique cancer cells.
ImpriMed will provide you and your vet with a Personalized Prediction Profile that will inform you of the best method to treat your pet. It will include responses to particular individual chemotherapy drugs as well as a CHOP protocol Response Prediction.
This information will be invaluable for making sure that your pet receives the most effective treatment available. Find out how to get your vet involved with ImpriMed today.