Full House actor Dave Coulier has just announced that he’s been diagnosed with stage 3non-Hodgkin lymphoma—an aggressive type of white blood cell cancer. Coulier, 65, was diagnosed in October 2024 after going to the doctor for an upper respiratory infection that caused extreme swelling in his lymph nodes. But the swelling continued to intensify—one lymph node grew to the size of a golf ball—so doctors recommended Coulier get a PET scan and a CT scan (imaging methods that help diagnose cancers and other internal injuries) and a biopsy (where doctors take a sample of cells to test them for cancer). Three days after the tests, Coulier’s doctors gave him the news of his aggressive case of non-Hodgkin lymphoma that took over his B cells—a type of lymphocyte (white blood cell) that makes antibodies to fight off infection.

“I went from, I got a little bit of a head cold to I have cancer, and it was pretty overwhelming,” Coulier told People. Thankfully, after receiving a bone marrow test that came back negative, Coulier discovered his “chances of curable went from something low to the 90 percent range,” he told People. For reference: because white blood cells are made in bone marrow in the body, bone marrow tests can help determine the type and severity of blood cancer you have.

So far, Coulier has completed the first of six chemotherapy sessions. He’s also preemptively shaved his head to avoid hair loss—a common side effect of chemotherapy medication—and tells People he has good and bad days.

Here’s what else to know about the blood cancer, and what treatment looks like.

What is non-Hodgkin lymphoma?

Non-Hodgkin lymphoma is one of the most common types of cancer in the U.S., accounting for 4 percent of all cancers, per the American Cancer Society. It’s a type of blood cancer that forms in the lymphatic system—a part of your immune system that protects you against infection and disease. The lymphatic system is made up of B and T lymphocytes (different types of white blood cells), lymph nodes, lymph vessels, the spleen, tonsils, thymus (an organ behind the breastbone), and bone marrow.

Most cases of non-Hodgkin lymphoma begin in the B lymphocytes, which was the case for Coulier. By stage 3 (the stage Coulier has), the cancer is considered aggressive and has likely spread to lymph nodes on both sides of the diaphragm and in the spleen.

Anyone can develop this type of cancer, but your risk is greater if you’re older, male, white, or have an underlying autoimmune disorder.

Signs and symptoms of non-Hodgkin lymphoma

Symptoms of non-Hodgkin lymphoma aren’t always apparent in the early stages. However, when symptoms do develop, they may include the following, per the Mayo Clinic:

• Swollen lymph nodes
• Fever
• Drenching night sweats
• Unintentional weight loss
• Fatigue
• Chest pain
• Difficulty breathing

What does treatment for non-Hodgkin lymphoma look like?

Oncologists (or, doctors who specialize in diagnosing and treating cancer) will recommend treatment based on your individual case, symptoms, and overall health status. Generally, treatment for non-Hodgkin lymphoma often involves a combination of chemotherapy, monoclonal antibodies, and steroids like prednisone. Depending on the stage of cancer, several rounds of these treatments may be needed, along with periodic PET and CT scans to monitor how well the treatment is working.

For many, including Coulier, these treatments come along with side effects: “Some days are nauseous and dizzy, then there’s other days where the steroids kick in, and I feel like I have a ton of energy,” he told People.

Ultimately, Coulier is hopeful. He shares his story to help inspire others to get tested early. “Take great care of yourself, because there’s a lot to live for,” he told People.