The American cross-country skier confirmed the diagnosis on social media and her website.

"The colour pink has taken on a new chapter in my life as I was recently diagnosed with breast cancer," wrote Randall, who has been known for dying her hair pink.

"Although we caught it early and the prognosis is good, my life will change quite a bit in the coming months.

"I have returned to Anchorage for treatment at the Providence Alaska Cancer Center.

"It's a scary thing to learn you have cancer and I have wondered every day since how this could have possibly happened to me.

"But I have promised myself that I will remain positive and active and determined throughout my treatment.

"I am going to bring as much tenacity, strength, and energy toward this challenge as I have throughout my entire career.

"I began my first round of chemo on Monday surrounded by great friends and family.

"I made sure to get a gym workout in beforehand, rode my bike to and from the hospital, and wore my happy shoes."

Randall competed at her fifth Olympic Games earlier this year, with Pyeongchang 2018 bringing a first Olympic medal.

The 35-year-old triumphed with Jessica Diggins in the women's team sprint competition, marking the United States' maiden Olympic title in the sport.

Randall is the only American to have won World Cup titles in the sport, having claimed three sprint crowns during her career.

At the end of the Winter Olympics, Randall was confirmed as an IOC Athletes' Commission member.

She was elected to the Commission with Finnish ice hockey player Emma Terho following an athlete vote.

Chinese speed skater Zhang Hong was chosen by the IOC as a third addition to the Athletes’ Commission.

Angela Ruggiero of the United States and Britain's Adam Pengilly were replaced when their terms came to an end, along with China's Yang Yang.