Metastasis: When Cancer Spreads
Leukemia is different from other cancers because it almost always spreads, or metastasizes, beyond its point of origin. Although leukemia begins in the bone marrow or blood, it usually doesn’t stay there for long, simply because blood flows. That’s what blood does; it circulates throughout the body. So while all cancers can become metastatic, it’s in leukemia’s nature to spread. When leukemia spreads, it usually does to the liver, spleen, testicles or central nervous system, i.e. the brain and spinal cord.
Is It The Same As Lymphoma?
Leukemia is very different from lymphoma. Both cancers begin in lymphocytes, the immature white blood cells manufactured deep inside bones. And due to this similarity, both leukemia and lymphoma are often referred to as “blood cancers.” But lymphoma, in contrast to leukemia, usually begins outside the bone marrow itself, at a lymphocyte’s next stop as it circulates through the body.
Here, in the lymph nodes, a network of small organs stationed throughout the body, lymphocytes can become cancerous, but often remain confined to the node itself. Of course, these categories are never fully distinct from one another. Some leukemia cases involve cancer cells in both the bone marrow and the lymph nodes. Likewise, some forms of lymphoma will come to invade the blood.
So how do cancer doctors tell the difference? When cancer is exclusively confined to the bone marrow, diagnosis is simpler, according to oncologists at the American Cancer Society. Most authorities believe that once 25% of the bone marrow has been replaced by cancerous white blood cells, the diagnosis should be leukemia.
An abnormally-high number of white blood cells circulating in the blood is also a good indication, though not dispositive, that a patient has leukemia. Lymphoma, on the other hand, is often characterized by swollen lymph nodes. While some node swelling can occur with leukemia, it’s a fair sign of lymphoma when a patient’s lymph nodes have become very large.
Symptoms & Blood Tests
Most common types of leukemia don’t present symptoms at first. That makes catching the disease early difficult and explains, in part, why many patients receive an unexpected diagnosis after undergoing a routine blood test. As we’ve already mentioned, blood tests that show high levels of white blood cells are a tip-off to physicians that someone has leukemia.
Of course, symptoms can also come into the picture. According to WebMD, the most common signs of leukemia include:
- enlarged lymph nodes
- enlarged liver or spleen
- abnormal bruising
- excessive bleeding
- swollen gums
- fever and fatigue
- chronic infection
- small rashes
It’s important to note that none of these symptoms are exclusive to leukemia. Doctors call symptoms like these “non-specific,” because they can be caused by numerous other conditions. That’s just one reason why diagnosing leukemia can be hard, because it can be misdiagnosed as other disorders that, on the surface, appear similar. A fever and fatigue can easily be dismissed as the common flu. The bruising and bleeding often related to cancer can be mistaken for any number of other blood conditions.
As we can see, symptoms aren’t usually enough to properly diagnose leukemia. Blood tests are certainly better, but they aren’t definitive, either. A biopsy, in which samples of body tissue are removed and then studied under a microscope, is the gold standard in diagnosing leukemia. To diagnose leukemia, the Cancer Treatment Centers of America says, biopsies of the bone marrow and lymph nodes are most common.
Biopsy: The Gold Standard Of Diagnosis
The first thing pathologists are looking for is evidence that some cells have become cancerous. But a properly-interpreted biopsy can also help in distinguishing between different types of the disease and, in some cases, can even provide clues to where the cancer began, a key step in differentiating between leukemia and lymphoma.
Biopsy continues to be the only conclusive way of diagnosing leukemia.
Lymphoid Vs. Myeloid Cancers
We’ve spent most of our time so far talking about lymphoid forms of leukemia, cancer cases that begin in the cells known as lymphocytes. That’s because most people get the sort of leukemia that starts in lymphocytes. Common in young children is acute lymphocytic leukemia, a form of the disease that can progress quickly and soon become fatal. Around 75% of leukemia cases diagnosed in children are classified as acute lymphocytic leukemia, or ALL.
Older patients, on the other hand, are more likely to develop myeloid forms of leukemia, which begin in blood cells that aren’t lymphocytes: red blood cells, non-lymphocyte white blood cells or megakaryocytes, which manufacture platelets.
Treatment, Remission & Ongoing Management
Cases of leukemia can also be classified based on their aggression, or how quickly they develop. Acute cancers grow fast; chronic cases move slowly and can go unnoticed for years. In the end, we’re looking at four basic subgroups of leukemia cases:
- acute lymphocytic leukemia (ALL)
- chronic lymphocytic leukemia (CLL)
- acute myeloid leukemia (AML)
- chronic myeloid leukemia (CML)
These differences matter a great deal and receiving an accurate diagnosis is essential. People with acute forms of leukemia usually get immediate treatment, because their cancer should be expected to grow rapidly.
Chemotherapy is usually the first-line therapy and doctors generally attempt an aggressive course of cancer-killing drugs in the beginning. Four weeks of chemotherapy, usually during a prolonged hospital stay, would be typical. A regimen of corticosteroids is sometimes prescribed to enhance the efficacy of chemo.
Many patients will also require blood transfusions at some point during their treatment, because chemotherapy can lower red blood cell production and impair the immune system. Sometimes this treatment regimen is referred to as “induction” therapy, because it’s designed to induce remission. In the context of leukemia, most doctors agree that the cancer has gone into remission when only 5% of the bone marrow is made up of “blasts,” or immature cells.
Induction, Consolidation & Maintenance Therapies
Chemotherapy doesn’t take sides; it kills both leukemia cells and healthy bone marrow cells. The goal of induction therapy is to eliminate immune system cells, including cancerous ones, so that the body can replace them all with healthy new ones.
Even when successful, induction therapy doesn’t usually eradicate the cancer entirely. Sometimes cancer cells are still lingering, even if they don’t show up in blood tests. Consolidation therapy is designed to take out these stragglers, because, if they were left alone, the remaining malignant cells could begin to regenerate. Another round of chemotherapy can be ordered and even supplemented with a stem cell transplant, where healthy immature cells are administered through an IV to help grow new blood cells.
Over the next few years, many leukemia patients will remain on a course of maintenance therapy and take low doses of a chemotherapy drug.
Learn More In A Free Consultation
Do you think you were misdiagnosed with leukemia as the result of a medical professional’s negligence? Or was your loved one given an inaccurate diagnosis that delayed necessary treatment? You and your family may be eligible to pursue compensation by filing a misdiagnosed leukemia lawsuit.
To find more information, contact our experienced medical malpractice attorneys today. At Monheit Law, our lawyers offer free consultations, where you can learn more about your legal rights and options at no cost and no obligation. Just call or fill out our online contact form to begin the process.