The Princess of Wales began preventative chemotherapy following a cancer diagnosis, which she first shared with the world in March. In an moving video message, featuring footage from time spent with her family, Kate shared an update on her health as well as her gradual return to royal duties The Princess of Wales began preventative chemotherapy following a cancer diagnosis, which she first shared with the world in March. In an moving video message, featuring footage from time spent with her family, Kate shared an update on her health as well as her gradual return to royal duties