CNN  —  An immunotherapy approach to treating advanced Hodgkin lymphoma may drastically increase patients’ chances of survival, including those as young as 12, according to a new clinical trial. The regimen, which involves the immunotherapy drug nivolumab along with three different chemotherapies, was found to result in a two-year progression-free survival rate of 92% in a phase three trial whose results were published Wednesday in the New England Journal of Medicine . As the study followed