The Low Down on Leukemia
Leukemia forms when blood cells in the bone marrow malfunction and form cancerous cells. The bone marrow produces white blood cells that effectively crowd the red blood cells and platelets. The excess white blood cells do not function properly, interfering with the body's immune defense as well as the ability to control bleeding and deliver oxygen to normal cells.
Leukemia is either acute (fast-growing) or chronic (slower- growing). It's further classified by whether it starts in myeloid cells or lymphoid cells. The four primary forms are acute lymphocytic leukemia (ALL), acute myelogenous leukemia (AML), chronic lymphocytic leukemia (CLL) and chronic myelogenous leukemia (CML).
In 2021, 61,090 people in the United States are expected to be diagnosed with leukemia, according to the Leukemia & Lymphoma Society. The organization estimates that 397,501 people are currently living with or are in remission from leukemia.
The five-year survival rate for leukemia has improved tremendously over the past 50 years and now stands at approximately 66 percent.
What are the symptoms?
Common symptoms of AML and ALL include fatigue, weight loss, flu-like symptoms, and bone and joint pain.
"A lot of times, they present with bruises because their platelet count is low," said Mohammad Maher Abdul Hay, M.D., a hematologist-oncologist at NYU Langone's Perlmutter Cancer Center. The most common reason chronic leukemia patients are referred to Abdul Hay for an evaluation is because their complete blood count (CBC) was abnormal.
Abdul Hay added that CML patients often present with abdominal pain.
"The reason is that the spleen gets very, very large," Abdul Hay said. "Actually, it can push on the stomach."
CLL patients present with "B symptoms," consisting of weight loss, night sweats, fever and chills.
How is leukemia diagnosed?
When a patient comes to Abdul Hay with high white blood cell counts, the first test at his disposal is a bone marrow biopsy, "the gold standard" in diagnosing. This diagnostic test determines whether cancer is affecting blood cells or marrow, and also depicts the extent of the disease.
Bone marrow testing typically involves a bone marrow aspiration followed by a bone marrow biopsy. The aspiration removes the liquid marrow sample and the biopsy is used to remove a small amount of bone filled with marrow.
With CLL, a bone marrow biopsy is not needed because they can do molecular testing, Abdul Hay said.
"Molecular testing is very important to identify what you're dealing with and genetics, looking for chromosome abnormalities," he said. "In CLL, sometimes you can get the blood results from peripheral blood, so really you don't need to do a bone marrow biopsy."
The risk factors
There are a number of factors that could increase your risk of developing leukemia.
"Exposure to toxins and smoking have been linked to ALL," Abdul Hay said. "We advise everyone not to smoke. If they work in gas stations or factories, they need to be careful."
Previous exposure to chemotherapy or radiation therapy has been associated with AML.
"We are seeing more therapy-related AML," Abdul Hay explained. "People have gotten chemotherapy for, say, breast or lung cancer, and then they come with AML."
For CLL, Abdul Hay noted the only factor that has been associated with it is exposure to Agent Orange, an herbicide used during the Vietnam War.
Genetics may play a factor. If you have relatives who have been diagnosed with leukemia, your risk may be increased. However, most individuals who develop leukemia don't have a family member with the disease.
For AML and ALL, the baseline treatment consists of chemotherapy, which uses cancer-killing drugs to target the leukemia cells.
"We very rarely do radiation in any of our leukemias," Abdul Hay said. "The only indication for radiation would be in ALL if they have brain involvement and they are not responding to local therapy."
Acute leukemias require intensive chemotherapy, which is a very strong intravenous chemotherapy known as induction.
"We have to keep them in the hospital for a month, and then they get what we call consultation and chemotherapy and stem cell testing," he added.
Another option for AML and ALL is stem cell transplantation that involves infusing the patient with new, healthy blood-forming stem cells after the cancer cells in the bone marrow have been destroyed with chemotherapy. Stem cell transplantation is not the first or primary treatment, but it may be used in high-risk patients or for patients who do not respond to prior treatments.
Treatment for CML can be outpatient with oral medications.
"With slow-growing leukemia, you can kill them easily and have a sustained response," Abdul Hay said. In fact, in 55 percent of these cases, a patient does not need anything more than one pill a day.
A life-changing moment
When Abdul Hay sees a patient with acute leukemia, he explains to them that their life will drastically change.
"They're going to get sick, and a lot of them will lose their hair," he explained. "It will be a lot of stress on them. I need to prepare them mentally as well as physically for what's coming next. I think at that moment it's life-changing for them."
He often gets asked by patients if they will be able to have children and, if not, if they'll have time to have an egg harvest to preserve fertility.
"A lot of times, unfortunately, because of the acuity of leukemia, they don't have the luxury to do so," he said. "Acuity requires urgent treatment."
In the 1950s, most of those with leukemia died, especially children and teens. We've come a long way in the last 70 years. According to the Leukemia & Lymphoma Society, the five-year relative survival rates overall from 2010 to 2016 were for ALL, 72.1 percent overall and 92.5 percent for children under 15; for AML, 29.8 percent overall and 70.6 percent for children under 15; for CLL, 88.6 percent; and for CML, 71.7 percent.