This form of leukemia is estimated to strike almost 6,000 people this year.

Former Biggest Loser contestant Daniel Wright died on Sunday after a two-year battle with cancer. Wright was diagnosed with acute lymphocytic leukemia in 2017, nearly a decade after his appearance on the reality show in 2009.

After finding out he had cancer, Wright struggled with his illness for months, undergoing different forms of treatment. Wright had returned to work in 2018 and was getting back into his usual routine when he relapsed this past December, according to his GoFundMe page. Four days ago, his wife reported on Facebook that her husband had started vomiting blood.

Credit: NBC/Getty Images

Acute lymphocytic leukemia, also known as acute lymphoblastic leukemia (or ALL), is the most common type of leukemia (cancer of the blood and bone marrow). According to the Mayo Clinic, symptoms of ALL include bleeding from the gums, frequent infections, bone pain, severe nosebleeds, and swollen lymph nodes around the neck and groin. Fever, shortness of breath, and fatigue are also symptoms of the disease.

Factors that can put a person at higher risk of this cancer include undergoing previous radiation treatments and having a close family member with ALL. Children, particularly males, are more susceptible. People with certain genetic disorders, such as Down syndrome, are also more likely to develop ALL. Treatment include chemotherapy and bone marrow transplants.

According to the National Cancer Institute, an estimated 5,930 cases will be diagnosed this year in both men and women; 1,500 deaths will be attributed to ALL in 2019 as well. Patients who experience relapse after remission usually die within a year, even if a second complete remission is achieved.

While it's not known if Wright had any of these risk factors, one thing that does not cause ALL is obesity. During his time on the show, Wright lost a total of 253 pounds; his starting weight was 454 pounds.

Wright's wife has not posted on Facebook since his death, but many his former costars have spoken out.

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