From the early 1980s, when Mitchell's health began to fail, until 1992, when she died, her work changed significantly. In 1984, she was diagnosed with advanced oral cancer and a mandibulectomy (removal of the jaw) was advised. In October, she obtained a second opinion from Jean-Pierre Bataini, a pioneer in radiation oncology with the Curie Institute, whose therapy was successful, but left Mitchell with a dead jawbone (osteonecrosis), along with anxiety and depression. She had quit smoking on doctor's orders, but remained a heavy drinker.