‘Aquaman’ Star Jason Momoa, 42, Calls Out For Bone Marrow Donor To Help His Friend Fighting Leukemia: ‘Be A Hero!’

Momoa's close friend, Travis Snyder, who's the founder of The Color Run, was diagnosed with leukemia in 2015. He's gone through chemotherapy, which put him into remission, but Snyder's cancer has since relapsed three times, most recently in March.

His only treatment option now is a blood stem cell transplant, and that's where Be The Match comes in. It's a national marrow donor program, and people can sign up online here.

Snyder is in need of a full match, and he didn't originally have any full matches on the registry, which is why Momoa is calling on more people to donate. It's possible for people to receive transplants from "half matches," but finding a full match is preferred.

"(When I was first diagnosed) you get dealt the worst card of leukemia and then you don't have a match. It was really hard," Snyder told People. "Throughout all of this, I think about my kids. Each relapse has been the hardest conversation to have with them. I just want to be able to keep raising these boys."

Snyder also told People how thankful he is for Momoa's friendship and support during this hard time.

"Some of my friends kind of shrink when you're in trouble, or it becomes kind of surface-y," he said. "And Jay was just right there again."

Stem Cell Transplant

To prepare for a stem cell transplant, first doctors have to be confident that you're as fit and healthy as you can be.

A stem cell transplant is used to treat blood cancers, such as acute myeloid leukemia and lymphoma, as well as multiple myeloma and certain blood or immune system disorders. When the transplant uses healthy blood-forming cells (stem cells) from a donor, the procedure is called an allogeneic stem cell transplant.

"We don't believe that chemotherapy, for the majority of leukemias, is sufficient in order to cure patients of their disease, forever," Dr. Caitlin Costello, a hematologist-oncologist at UC San Diego Health, previously told SurvivorNet. "And so a transplant is an opportunity to do that cure patients with leukemia."

Preparing for a Stem Cell Transplant to Treat AML, While Finding a Matching Donor

After the patient's own stem cells have been destroyed by high doses of chemotherapy (like in Snyder’s case) or radiation, they’re replaced with healthy stem cells from a donor. (In a variation on this procedure, an autologous stem cell transplant, the patient's own stem cells are used.)

Patients will undergo testing to determine the strength of their heart, lungs, liver, and kidneys, according to Dr. Costello.

"And while you are going through this, your donor, who has not been identified, is being searched for," she added.

A sibling donor is ideal, Dr. Costello said. Siblings have a 1 in 4 chance of matching; a close relative may also be a potential match. When the donor is an identical twin, the procedure is known as a syngeneic stem cell transplant, and offers perfect genetic match.

Donor cells can also come from an unrelated donor who’s genetically similar to the patient.

"If a sibling is not a match or is unavailable, we'll be looking for an unrelated donor in a worldwide registry (like Be The Match). So while you're undergoing your testing, your transplant doctor is identifying a donor who would be a good option for you," Dr. Costello said.

What Acute Myeloid Leukemia (AML) Patients Should Expect During a Bone Marrow Transplant

Understanding Acute Myeloid Leukemia

Acute myeloid leukemia, also known as AML, is a cancer that affects bone marrow the spongy tissue inside of your bones. It’s a rare cancer overall, but it’s the most common type of leukemia in adults, like Snyder. Children rarely get AML.

"To understand acute myeloid leukemia, you have to understand how the bone marrow works," Dr. Mikkael Sekeres, former director of the Leukemia Program at Cleveland Clinic Cancer Center and current chief of the Division of Hematology at University of Miami Health System, previously told SurvivorNet. "The bone marrow is the factory that makes all of the cells that wind up in our blood stream."

What is Acute Myeloid Leukemia (AML)?

This so-called factory makes red blood cells that bring oxygen to our tissues, white blood cells that make up the immune system, as well as platelets, which help stop bleeding, Dr. Sekeres explained. All of these cells perform essential functions in the body, and a spike or decline in any of them can lead to some serious health issues.

"When a person has cancer of the bone marrow, such as acute myeloid leukemia or myelodysplastic syndromes, that factory gets broken. These are cancers," he said. "Cancers grow, and they grow in an uncontrollable way."

Dr. Sekeres pointed out that the way blood cancer grows is different from the way other, solid-tumor cancers grow. With breast cancer, for example, someone may develop a lump or a tumor that grows overtime. With AML, as cancer grows in a confined space (the bone marrow), the normal cells in this space that would be making the red blood cells, white blood cells and platelets, begin dying off. This leads to the bone marrow being filled with cancer cells.

How to Recognize Symptoms of Acute Myeloid Leukemia

There are many symptoms of AML, including:

AML symptoms include:

• Fever
• Frequent infections
• Feeling tired or weak
• Easy bruising or bleeding
• Petechiae, which are blood spots under the skin
• Weight loss or loss of appetite
• Dull or sharp bone pain, usually in the legs and arms
• Pale skin

If you are experiencing any of these symptoms (and are at an increased risk of developing AML), talk to your doctor.

Risk factors that put a person at an increased risk of developing AML include:

• If you are 65 years of age or older: The risk rises as you age.
• If you are male: Men are more likely to get AML than women.
• If you have been treated for cancer in the past: If you have had certain chemotherapy or radiation treatments, they might increase your risk of getting AML.
• If you have had certain exposures: Radiation or chemicals like benzene and formaldehyde might increase your risk.
• If you smoke, or have smoked in the past: Cigarette smoking has been linked to AML.
• If you had another blood disorder: Myelodysplasia or myelofibrosis could put you at greater risk.
• If you have certain genetic disorders: Down syndrome and other genetic syndromes affect AML risk.

Contributing: SurvivorNet staff reports

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