In a deeply personal message, she said it was “a relief to now be in remission”, adding: “I remain focused on recovery.”
“As anyone who has experienced a cancer diagnosis will know, it takes time to adjust to a new normal,” she wrote, in a social media message signed by “C” for Catherine.
“I am however looking forward to a fulfilling year ahead. There is much to look forward to. Thank you to everyone for your continued support.”
Hours after she was announced as the new joint patron, with Prince William, of the Royal Marsden, the princess wrote: “I wanted to take the opportunity to say thank you to The Royal Marsden for looking after me so well during the past year.
“My heartfelt thanks goes to all those who have quietly walked alongside William and me as we have navigated everything.
“We couldn’t have asked for more. The care and advice we have received throughout my time as a patient have been exceptional.
“In my new role as Joint Patron of The Royal Marsden, my hope is, that by supporting groundbreaking research and clinical excellence, as well as promoting patient and family wellbeing, we might save many more lives, and transform the experience of all those impacted by cancer.”
It is the first time the princess, or the palace, has used the word “remission” to describe Catherine’s health.
In September, she said: “Doing what I can to stay cancer-free is now my focus. Although I have finished chemotherapy, my path to healing and full recovery is long and I must continue to take each day as it comes.”
In March, she shared news of her diagnosis with the world in a statement reading: “In January, I underwent major abdominal surgery in London and at the time, it was thought that my condition was non-cancerous. The surgery was successful.
“However, tests after the operation found cancer had been present.
“My medical team therefore advised that I should undergo a course of preventative chemotherapy and I am now in the early stages of that treatment.”