A volunteer fills a balloon with steel balls to make breast prostheses for mastectomy bras at a centre run by the "Reto" Group for Full Recovery of Breast Cancer in Mexico City October 18, 2012. Breast cancer has been the leading cause of death in Mexican women since 2006, according to the group. The World Day Against Breast Cancer is commemorated on October 19. REUTERS/Edgard Garrido (MEXICO - Tags: HEALTH ANNIVERSARY)