The news shook the film industry last weekend: Chadwick Boseman, who played T'Challa in Black Panther, died of colon cancer at the age of 43. He was diagnosed in 2016. Since the news broke, many celebrities and fans have paid tribute to the actor and his career, but his tragic death also started a conversation on colorectal cancers, which are claiming more and more victims every year in the United States, as well as in Europe.What is colorectal cancer?According to the Cancer League, colon cancer is a disease that affects the cells that line the inside of the colon or rectum. Typically, a normal cell will transform and start multiplying in a disorderly fashion following a mutation. Despite a steadily declining death rate, this cancer remains one of the most frequent, as well as one of the deadliest. It's usually seen in people over the age of 50 (95% of cases). But it can also occur in younger people, as it did for actor Chadwick Boseman. That's why The American Cancer Society recently lowered its recommended age for a first screening to 45, instead of 50. In fact, the disease can be cured in the vast majority of cases if caught early.The numbers are alarmingThe number of cases of colorectal cancers has skyrocketed in the last few decades: in the United States, there's been a 50% increase in people under 50 since 1994. This age group now accounts for 11% of colon cancers and 18% of rectal cancers. A similar trend was observed in Europe and France: according to the Foundation for Medical Research (FRM), the rate of colorectal cancer in France is "high," with 44,872 new cases in 2017. Also in 2017, this disease caused 17,684 deaths. According to the National Cancer Institute (Inca), one in 30 people will have it in their lifetime.As for the causes of this widespread increase, researchers agree that environmental factors such as changes in lifestyle and diet are to blame. But the rise in the number of cases is still poorly understood by the medical community.How is it detected?Symptoms of colorectal cancer are hard to pin down and are only noticeable in the more advanced stages of the disease. Symptoms can range from sudden and persistent constipation or diarrhea to bloody stools, abdominal pain, rapid weight loss, or severe fatigue.There are several exams that can help diagnose it. The most effective one is a colonoscopy, which is unfortunately quite invasive and turns off many patients. Another method is to look for microscopic traces of blood in the stools. At the moment, perhaps the best option is to get a test known as Hemoccult, which is done over several days, following strict directions. It consists of depositing fragments of stools collected over several days on glass plates that will then be sent to a qualified laboratory. The results are usually available within fifteen days.