The Multinational Association for Supportive Care in Cancer risk index score developed, through a multinational collaboration, was published in 2000 with the aim to identify patients with chemotherapy-induced febrile neutropenia at low risk of serious medical complication development. It has been endorsed as a reliable tool since 2002 by Infectious Diseases Society of America. Ten years after, we thought worth to review its use, its characteristics in the external validations that occurred after the initial publication and also to review how the recognition of a group of patients at low risk has changed the management of febrile neutropenia. We also raise the issue of identification of high-risk patients that remains a challenge today.