Princess Kate revealed she is undergoing treatment for a cancer diagnosis. What is preventative chemotherapy?

Catherine, the Princess of Wales, announced Friday that doctors discovered cancer in tests conducted after she underwent major abdominal surgery in January. The 42-year-old princess is now undergoing a course of preventative chemotherapy as advised by her medical team, she said in a video. Here is what that may involve.

What is preventative chemotherapy?

Preventative chemotherapy, which is usually referred to as "adjuvant chemotherapy," is an early treatment that is used to reduce the chance of cancer returning, even if all visible cancer was removed in a surgery, according to the Mayo Clinic.

When cancer is removed from the body, there is always a chance undetectable microscopic bits of cancer remain and could grow. This treatment is meant to wipe out those tiny cells, CBS News chief medical correspondent Dr. Jon LaPook said.

"The idea is, well maybe there is some tiny microscopic cells somewhere, and we don't want to give them a chance to grow up," LaPook explained. "We want to nail them right now when they're not yet clumped together and growing into big masses."

How is the treatment given?

There are many types of adjuvant therapies including chemotherapy, radiation therapy, hormone therapy and more. The princess is receiving adjuvant chemotherapy, the most common form of cancer treatment, which is typically three months long, LaPook explained. 

The treatment can take various forms depending on the type of cancer, including pills, an IV, creams, injections and more, the Mayo Clinic says. In the most common scenario, chemotherapy is given as an infusion into a vein, usually by inserting a tube with a needle into a vein in the arm.

What are the possible side effects?

While this type of treatment is an attempt to prevent cancer from growing and spreading, it is still an intensive process, and can have multiple potential side effects that may include fatigue, and an increased risk of contracting infections, LaPook said. 

According to the Mayo Clinic, other possible side effects include nausea, hair loss, mouth sores, loss of appetite, easy bruising and bleeding. The clinic says many of these can be prevented or addressed with treatments.

However, there are also some potential long-term side effects that do not appear until months or years after chemotherapy, such as damage to lung tissue, heart problems, infertility and risk of second cancer, the clinic outlines.

Does it work?

The success of preventative chemotherapy is really dependent on the type of cancer, how aggressive it may be and what stage the recipient is in, the Mayo Clinic says. 

LaPook spoke with a cancer expert at NYU Langone Health, who said the process can be difficult, but that "people tend to have a 100% recovery afterwards in terms of getting their strength back and getting back to normal function."

He added that the fact that this seems to have been caught early is potentially a good sign for the princess.

"Even though we're shocked by it and she was shocked by it, in the big picture, it's actually relatively encouraging that it was found so early," La Pook said.

In:
• Chemotherapy
• Cancer
• Catherine Princess of Wales

Simrin Singh

Simrin Singh is a social media producer and trending content writer for CBS News.