On Saturday, the former Scotland centre announced the news on social media.
The 57-year-old thanked his fans for their messages of encouragement and shared photos of himself following treatment.
“Thank you for all your encouraging notes that are helping me get through my chemo for non-lymphoma,” Hodgkin’s he stated. Apart from the hair, I am halfway through therapy, which is doing great!”
Hastings endured treatment and chemotherapy for non-Hodgkin lymphoma some years ago.
It is a form of cancer that affects your immune system and develops in the lymphatic system, a network of tubes and glands that runs throughout your body.
Hastings was captained by Scotland 65 times and travelled with the British and Irish Lions twice, visiting Australia in 1989 and New Zealand four years later.
He was a major player of Scotland’s Grand Slam-winning squad in 1990, with his older brother Gavin, while playing club rugby for Watsonians. He retired from international rugby as Scotland’s most capped player in 1997, and he is still the most capped centre.
Hastings presently works as a rugby commentator for a variety of networks, including BT Sport, Sky Sports, ITV, and the BBC.
Among those to send messages of support was former Scotland captain Chris Cusiter, who tweeted: “Stay strong Scott. Sending you and the family our love.”
Former England lock Martin Bayfield said: “Keep going Scotty. Sending all our love.”
Another old England adversary, Brian Moore, said simply: “Keep battling mate.”
The 65-times capped Scotland player said: “My cancer is very treatable and non life-threatening.
“Thanks for all your supportive messages that are helping me get through my chemo.
“I am halfway through treatment which is going well apart from hair!”
His wife Jenny said: “Every day is a gift.”
Scott has featured as a guest presenter on STV’s daily lifestyle show The Hour a few times after his retirement, the first time in November 2009, with main anchor Michelle McManus. The Scottish magazine show airs at 5 p.m. on weekdays.
He was a co-commentator for ITV’s coverage of the Rugby World Cup in 2011. He made his debut on the BBC’s political debate show Question Time on July 10, 2014. During the 2014 Scottish independence referendum, Hastings backed the Better Together No campaign.
Scott was a member of the ITV team that covered the 2019 Rugby World Cup.
He is a regular host of “Just a Sports Quiz,” an annual event hosted in Murrayfield to raise funds for Motor Neuron Disease research.