The event, which is supported by fashion designer Ralph Lauren, will celebrate the work of the hospital and its cancer charity.
As president of the charity, Prince William will greet a range of guests including actors, models, fashion designers and cancer survivors. The Telegraph reported that Oscar-winning actress Cate Blanchett and Harry Potter star Emma Watson are expected to attend.
Lauren, who runs the Pink Pony project, donates proceeds from sales of his designs to the Royal Marsden.
The Duchess of Cambridge and Prince George are not scheduled to attend the evening.