Kate Middleton and Prince William Announce Big News as She Visits the Hospital Where She Had Cancer Treatment

The Princess of Wales visited the Royal Marsden Hospital in London on Tuesday, Jan. 14

Kate Middleton and Prince William have made a poignant joint decision.

The Prince and Princess of Wales are pairing up to serve as patrons of the hospital where Kate, 43, received cancer treatment for much of 2024.

Kensington Palace announced Tues., Jan. 14, that Kate and William have become joint patrons of the Royal Marsden NHS Foundation Trust.

William, 42, has had a close relationship with the Royal Marsden Hospital in London for many years, as he was named president in 2007 — a role that had been previously held by his late mother, Princess Diana.

Princess Kate visited the hospital on Tuesday as the patronage was announced.

The surprise outing was to "show her gratitude to the incredible team" at the medical center, a spokesman for Kensington Palace said. It marked Kate's first solo engagement since 2023 and a rare one in public following her diagnosis.

Related: Kate Middleton Surprises Cancer Patients at the Same Hospital Where She Was Treated Last Year in Rare Public Outing

Dame Cally Palmer, chief executive of the Royal Marsden NHS Foundation Trust, said of Kate's visit, “We were honored to welcome Her Royal Highness the Princess of Wales to the Royal Marsden in Chelsea this morning, and are delighted that Her Royal Highness is now joining His Royal Highness the Prince of Wales in becoming Joint Patrons of our specialist cancer center.”

"We are incredibly fortunate to receive Royal Patronage — it is inspiring for staff and patients and enables us to shine a light on the outstanding work our staff deliver every day for patients and their families," Palmer continued in a statement.

Opened in 1851, the Royal Marsden is the world's first clinic to have dedicated itself to cancer diagnosis. It is now a world-leading center with multiple locations in London.

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Kate is still managing her gradual return to public life following the ending of her chemotherapy treatment, which she announced in an intimate family video in September 2024.

She had revealed her cancer diagnosis in a personal video message in March 2024, calling the news a "huge shock." The type of cancer has never been revealed.

The princess started her cancer treatment in February 2024 — a little over a month after she had undergone major abdominal surgery.

The royals' last public visit to the hospital was in June 2023, when William opened the facility's Oak Cancer Centre in Sutton.