Chadwick Boseman, who portrayed King T'Challa in Black Panther, died after a four-year private battle with colon cancer.

The 43-year-old continued to work on projects and films during and between his medical treatment, which included ‘countless’ operations and chemotherapy, his family said in a statement.

“Chadwick was diagnosed with stage III colon cancer in 2016, and battled with it these last four years as it progressed to stage IV. A true fighter, Chadwick persevered through it all, and brought you many of the films you have come to love so much,” the statement read.

What Is Colon Cancer?

Colon or colorectal cancer is a type of cancer that begins in the large intestine (colon) or the rectum, according to Mayo Clinic. The colon is the final part of the digestive tract.

The cancer begins when small and benign clumps of cells, called polyps, form inside the colon. While most of these are harmless, some may turn into colon cancers over a period of time. If detected early, the polyps can be removed and cancer can be prevented.

Colon cancer can affect both men and women. As the symptoms may not be very apparent in the early stages, doctors recommend regular screening tests to identify and remove polyps in time. As the disease gets worse, there may be rectal bleeding, abdominal discomfort, changes in bowel habits, weakness and unexplained weight loss - but these differ for everybody. By the time such symptoms appear, tumors tend to be bigger and harder to treat, says WebMD.

It also lists down the stages of colon cancer:

• Stage 0: Cancer is in the innermost lining of the colon or rectum.
• Stage I: The disease has grown into the muscle layer of the colon or rectum.
• Stage II: Cancer has grown into or through the outermost layer of the colon or rectum.
• Stage III: It has spread to one or more lymph nodes in the area.
• Stage IV: It has spread to other parts of the body, such as the liver, lungs, or bones.

Some risk factors include old age, unhealthy diet, high alcohol consumption, a family history of colorectal cancer, having Crohn’s disease or irritable bowel disease, among others. Lifestyle changes and regular screening can help prevent it.