Understanding blood cancers

Blood cancer encompasses many kinds of hematologic malignancies, including but not limited to leukemia.

September is National Blood Cancer Awareness Month. While people may associate blood cancer with leukemia, the acute form of this cancer affecting adults accounts for about less than two percent of all cancers, according to Suresh Kumar Balasubramanian, M.D., a member of the Malignant Hematology Multidisciplinary Team at the Barbara Ann Karmanos Cancer Institute and assistant professor in the Department of Oncology at Wayne State University School of Medicine.

“Acute leukemias occur substantially less compared to lymphomas and myelomas in our practice,” he said. “Lymphomas and myelomas are more commonly diagnosed than acute leukemias.”

Broadly speaking, blood cancers can be categorized in three ways: myeloid, lymphoid and plasma cell dyscrasias. Dyscrasia is defined as an abnormal or disordered state of the body or of a body part.

Myeloid cancers

Myeloid cancers are a type of cancer of the blood and bone marrow, characterized by excess immature white blood cells. Acute myeloid leukemia (AML) is more common in older adults than children.

Chronic myeloid leukemia (CML), a rare cancer, originates in the spongy tissue inside the bone, causing white blood cells to proliferate and enter the blood stream in various stages of immature forms. It is more prevalent in adults.

Myelodysplastic syndrome (MDS) is a group of disorders that disrupts normal production of various blood cells and is a chronic disease that affects four out of every 100,000 adults. Adults who receive an MDS diagnosis are typically in their 70s. It is uncommon in people younger than those in their 50s.

Lymphoid cancers

Broadly speaking, there are two different kinds of lymphoid blood cancers: B and T cell types. They are typically categorized into two groups: Non-Hodgkin Lymphoma and Hodgkin Lymphoma. These blood cancers, which affect adults and children, develop from the two main types of white blood cells called lymphocytes: B lymphocytes (B cells) and T lymphocytes (T cells).

These cancerous cells can travel to different parts of the body, including the spleen, bone marrow, blood or other organs. From there, they can accumulate and form tumors. Different types of lymphoid cancer can affect adults in different age groups. Some affect younger patients in their 20s to 30s, while others are predominant in older patients.

Chronic lymphocytic leukemia (CLL), more prevalent in the Western Hemisphere, frequently affects individuals in their 70s. However, it is not uncommon to see this type of blood cancer in patients in their 30s. Acute lymphocytic leukemia (ALL) is more common in children than in adults.

Plasma Cell Cancers

Plasma cell cancers occur when abnormal plasma cells grow within the bone marrow (the softer part of the long bone and hip bones). Plasma cells may excrete certain proteins in excess quantity than what is normal. Plasma cell cancers include multiple myeloma, which is caused primarily from the expansion of the cancer cells into the bone, causing damage. In the case of multiple myeloma, the abnormal proteins also cause other organ dysfunction, including damage to the kidneys. The median age of multiple myeloma patients is around 60.

How do blood cancers form?

While adopting a healthy lifestyle, including not smoking, keeping weight down and eating a healthy diet is generally a good rule to follow when it comes to preventing cancer, Dr. Balasubramanian states that some blood cancers can occur despite lifestyle factors. In those patients, an inherent genetic link may have predisposed them to such cancers.

“There are patients who have a healthy lifestyle who could be diagnosed with a blood cancer,” he said. “We know some of the genes that cause these cancers though we don’t know all about those genes. We are gaining more and more information (about the genetic links to cancer) … but there is still a lot of information needed about how blood cancers develop.”

In some instances, one genetic mutation may trigger a second genetic mutation, which then leads to a blood cancer diagnosis.

“It’s pretty hard to answer what is exactly the driver of blood cancer,” he said.

However, Dr. Balasubramanian believes that researchers will be able to identify those drivers in the coming years, thanks to ongoing research that is currently underway.

Blood cancer signs and symptoms

Some blood cancers, such as myeloid leukemia, have no signs that show up prior to diagnosis. Symptoms can also be vague since blood cancer by definition affects cells that serve different purposes, such as carrying oxygen through the body, helping blood clot or preventing infections. However, symptoms of blood cancer may include:

  • Anemia
  • A rapid heartbeat that occurs due to anemia
  • A feeling of weakness related to anemia
  • A pale appearance • Random bleeding under the skin
  • Excessive bleeding from a cut
  • Bruising easily
  • Infections
  • Glandular swelling (such as the lymph glands)
  • Weight loss
  • Drenching sweats
  • Bone pain

Dr. Balasubramanian said that blood cancer symptoms can come on rapidly compared to the behavior of solid tumors. Because of this, hematologists typically have to quickly determine a patient’s treatment path.

“It is challenging because we don’t have as much time to contemplate different courses of treatment,” he said.

Treating blood cancers

Treatment for blood cancers differs from those for solid tumors.

“In hematology, treatment for the most part is curative in intent at the outset,” Dr. Balasubramanian said.

Some hematologic cancers are treated by stem cell or bone marrow transplants. While cytotoxic chemotherapy was typically used in the past, the last 20 to 30 years have brought about major changes in the ways blood cancers are treated, including integrative therapies, such as chemotherapy plus targeted treatment and/or immunological therapies.

Karmanos was the one of the first hospitals in Michigan to conduct clinical trials in CAR-T therapy, which genetically modifies the patient’s white blood cells to target and kill cancer cells. Right now, CAR-T therapy is used for an aggressive form of Non-Hodgkin Lymphoma outside clinical trials and some other blood cancers currently in clinical trials.

Dr. Balasubramanian explained that 40-50 patients participated in the initial CAR-T clinical trials and 50-60 have undergone the therapy at Karmanos since it was approved by the FDA in October 2017.

“That has opened up a completely different avenue of treatment,” he said. “We have made considerable progress with the CAR-T cell therapy.”

Dr. Balasubramanian also mentioned that some blood cancers, such as chronic myeloid leukemia, can be managed long-term with oral chemotherapy.

“Today, it’s like people who have to live with diabetes. It’s a disease that is well-managed,” he said.

Karmanos’ hematologists are able to treat all types of blood cancers, considering that the Institute is one of a select group of cancer centers in the country that holds an NCI-designated comprehensive cancer center status. Karmanos has held this designation continuously since 1976. The Institute also has a robust clinical trials program and offers every eligible patient the opportunity to take part in a clinical trial.

“There is definitely hope (for patients) in receiving treatments. It’s not the end game for people who are diagnosed with a blood cancer,” Dr. Balasubramanian said. “In the past 20 years, there’s been a phenomenal change in hematology and oncology with just the amount of research that is being produced.”

He encourages individuals who have been diagnosed with a blood cancer to seek out medical professionals who specialize in treating their specific type of cancer, preferably at an academic-based hospital, which provides more comprehensive care.

“Reach out to a cancer center that has the expertise to treat blood cancers,” he said. “Karmanos oncologists and hematologists are more approachable and more community-friendly. And like every academic-based center, we are better connected with the community and have all of the state of the art facilities including cutting-edge clinical trials and techniques that stand at par with global cancer treatment standards. We do things more collectively and have an integrative strategy involving a multidisciplinary approach in every treatment recommendation we make,” he added.

Suresh Kumar Balasubramanian, M.D.