What to Know About Appendiceal Cancer

The actor Adan Canto’s death from appendiceal cancer—or cancer of the appendix—came as a shock to his fans. Canto, who died on Jan. 8 at age 42, had kept his diagnosis and treatment private, and his family has not publicly shared any information about how long Canto lived with the disease.

Here’s what to know about the rare condition.

What is appendiceal cancer?

A rare form of intestinal cancer, appendix cancer—like colorectal cancer—is on the rise for unknown reasons. “In the last century, the rates were around one to two per million people, but more recently, it’s been nearly one per 100,000 people,” says Dr. Alok Khorana, a medical oncologist and colorectal cancer researcher at the Cleveland Clinic.

Cases in people under 50, like Canto, are rarer still. That may partly be because they are underdiagnosed. Appendiceal cancer can be harder to spot in young people than in older patients, says Khorana, primarily because doctors just aren’t looking for it as often. “Among intestinal cancers in younger people, diagnosis does take longer, and they tend to need to go to multiple different health care providers before a diagnosis is made,” he says.

How is appendix cancer diagnosed? 

Appendix cancer can occur without any obvious symptoms until a person experiences pain in the area around the appendix. People are most often diagnosed when they show up at the hospital with what they think is just a burst appendix, Khorana says, since it’s standard procedure to test any appendix being removed for any reason.

Read More: Your Appendix May Not Be Useless After All

The difficulty of diagnosis is also related to the appendix itself. The small, tube-shaped organ attached to the entry point of the large intestine may play a small role in the immune defense of the digestive system, but other than that, the appendix serves no critical function in the body. This means that issues that occur in the appendix rarely have downstream effects, enabling them to go potentially unnoticed in the absence of pain. On the other hand, the appendix can be removed from the body with no direct consequences, which can make early stages of appendiceal cancer much easier to treat than colorectal cancers, which occur in essential areas further along the digestive tract.

What causes appendix cancer?

Doctors aren’t sure what risk factors or events cause appendiceal cancers, but many are the result of a neuroendocrine malfunction that turns the organ’s hormone-producing cells cancerous. A person’s prognosis depends on several factors, including the tumor’s location and if the cancer has spread, but the National Cancer Institute places the five-year survival rate for appendix cancer—if detected and treated before it spreads—between 67% and 97%.

How appendiceal cancer is treated

Appendiceal cancer begins in the interior lining of the appendix. In the more dangerous cases, quickly replicating cells can cause a build-up of tissue and protective mucus substantial enough to burst the organ open. “When it’s localized to the appendix, and the appendix comes out, that’s when it’s caught early,” says Khorana. This generally happens in cases where the appendix is removed during an unrelated digestive surgery or when pain first appears.

But if cancerous cells flow out of the appendix, they can spread to other parts of the body. More intensive treatment, like chemotherapy or a more invasive abdominal surgery, may be required for these cases. When caught in the later stages of the disease, the survival rates for these cancers vary greatly, but are lower than the rates for cases involving neuroendocrine tumors. Those with stage IV appendiceal cancers can face five-year survival rates as low as 10%.

People should pay attention to and seek care for pain in the right lower quadrant of the intestines, where the appendix lives, Khorana says. The appendix isn’t checked during regular colonoscopies, as it’s “almost like a closed portion of that organ,” he says—so being vigilant is important.