Kate, Britain's Princess of Wales, said on Wednesday that she had to put on a "brave face" throughout and following her cancer treatment last year, describing the ordeal as a life-changing experience.
Kate, 43, announced in March last year that she would undergo a course of chemotherapy after tests taken following major abdominal surgery revealed that an unspecified form of cancer had been present.
She completed the course of treatment in September, and said earlier this year she was in remission.
"You put on a sort of brave face, stoicism through treatment, treatment's done, then it's like, 'I can crack on, get back to normal', but actually the phase afterwards is really... difficult," Kate said during a visit to a hospital in Essex, southeast England.
Speaking to staff, patients and volunteers at the hospital, the princess emphasised the importance of support after treatment, noting that while patients may no longer be under clinical care, they often still struggle to "function normally at home" as they once did.
Kate described the cancer diagnosis and treatment as "life-changing" for both patients and their loved ones, according to PA Media, adding: "It's a rollercoaster, it's not one smooth plain".
The princess has been gradually resuming her public royal role but missed the Royal Ascot horse racing event last month, with a royal source citing her need for balance following her cancer treatment.