By Richard C. Frank, MD
A 60-year-old woman came to see me recently for an oncology consultation and she was, as is often the case, very anxious. Her primary care doctor had told her that her routine annual blood test showed she might have leukemia and that she should call my office for an appointment. Since hearing the word “leukemia” she had not slept and was fearful for her life. After reviewing her records and blood smear under the microscope and learning that she was otherwise in perfect health, I was able to reassure her that although she did have a type of leukemia, called chronic lymphocytic leukemia, her form of it would likely not need to be treated for some time and would probably not impact her life for many years. Needless to say, she breathed a big sigh of relief.
Chronic lymphocytic leukemia, or CLL, is one of the many types of blood cancers. Blood cancers derive from the cells of the bone marrow and lymph nodes. Involvement of the bone marrow may suppress normal blood formation and cause low blood counts, especially anemia (low red blood) and low platelets (blood cells that prevent bleeding). Involvement of the lymph nodes causes these pea-sized glands to enlarge to the point that they can either be felt (in the neck, underarms, or groin areas) or cause pressure on an internal organ (causing, for example, chest pressure or shortness of breath). These disorders are sometimes associated with weakness, night sweats, or weight loss. They often require a bone marrow biopsy and/or a lymph node biopsy for diagnosis. The following is a very brief overview of the blood cancers.
There are three main groups of blood cancers:
3. Multiple myeloma
A diagnosis of leukemia is made when the cells that cause a cancer are found circulating in the bloodstream. This can be detected by a routine CBC (complete blood count), which will often reveal an elevation of the white blood cell count (The word “leukemia” derives from the Greek terms for white (leukos) and -emia, meaning of the blood. There are four main types of leukemia (and several other less common types):
1. Acute myelogenous leukemia (AML): Most commonly affects those over 60 years of age but can occur in younger people. Requires intensive chemotherapy and often an allogeneic stem-cell transplant (blood stem cells from another individual) to be cured. New strategies are desperately needed for older individuals who cannot tolerate the standard, intensive approach.
2. Acute lymphocytic (or lymphblastic) leukemia ALL): The most common cancer in children, is highly curable with modern-day chemotherapy.
3. CLL: Can be detected incidentally (example above) if not causing symptoms or when it presents aggressively with enlarged lymph nodes, a very high white blood cell count (the malignant lymphocytes), and profound fatigue. Those who have symptoms due to CLL require treatment, often a combination of chemotherapy and an immune therapy. Younger patients may require a stem-cell transplant for cure. Several newer therapies in the advanced stages of research (such as the drug PCI-32765) will likely revolutionize the treatment of this disease.
4. Chronic Myelogenous Leukemia (CML): The treatment of this previously fatal form of leukemia was revolutionized by the development of the drug imatinib, followed by nilotinib and dasatinib. These pills, which are very well tolerated, drive the leukemia into remission in the vast majority of patients.
There are two main types of lymphoma, Hodgkin’s and non-Hodgkin’s, which are distinguishable by their appearance under the microscope to a pathologist examining a lymph node biopsy (most commonly). Hodgkin’s and 85% of non-Hodgkin’s lymphoma (NHL) are caused by the abnormal proliferation of an immune cell called a B-lymphocyte; 15% of NHLs are of T-cell origin. There are only a few types of HL whereas there are over 30 types of NHL. A precise diagnosis may require a second opinion on the pathology specimen. Treatments may range from observation to well-tolerated immune therapies (such as rituximab, which has revolutionized the treatment of NHL) to intensive chemotherapy and even a stem-cell transplant (using the patient’s own stem cells, called an autologous transplant, or an allogeneic transplant, depending on the situation). The evaluation of a patient with lymphoma will also involve CAT scans and often a PET scan.
This very complicated blood cancer is caused by the overgrowth in the bone marrow of an immune cell called a plasma cell, which secretes a protein into the bloodstream, called an “M-protein,” that can be detected by a test called an immunoelectrophoresis. The malignant plasma cells can also burrow into the hard bones of the body to cause little holes called “lytic lesions” that can weaken the bones and cause them to fracture. A revolution in the treatment of this cancer has occurred in the last 10 years with the introduction of an autologous stem cell transplant and new drugs such as lenalidomide (Revlimid) and bortezomib (Velcade).
Overall, the outlook for patients affected by a blood cancer has improved dramatically over the past 10 to 15 years. Ongoing research will ultimately lead to the cure of many of them. It is best to consult or be under the care of an expert in hematologic oncology. For more information, visit lls.org and myeloma.org.