Benjamin Seth Rosenbaum, 26, of Portsmouth, N.H., formerly of Acton, died on May 15, three years after being diagnosed with osteosarcoma. He was the son of Bob Rosenbaum and Cheryl Steinberg of Acton and Chilmark, and the brother of Becky Rosenbaum of Providence, R.I., formerly of Acton.

Ben was a 2001 graduate of Acton-Boxborough High School. He graduated from the University of New Hampshire in 2005 with a degree in geography and computer science. Ben worked at the Martha’s Vineyard Airport during the summer while in high school and college. In his senior year at UNH he interned at Global Relief Technology based in Portsmouth, and joined the company full-time upon graduation. The company provides cutting edge technology for relief agencies working in the field.

He spent a great deal of time in the field working with a variety of groups including the Red Cross, FEMA and the Marine Medical Corps. He accompanied the Marines in Thailand providing medical services in remote areas of the country. He was in Louisiana after Hurricane Katrina and was in Houston, Tex., during Hurricane Rita. Ben loved to travel, making trips all over the world. He was an avid scuba diver and a big Boston sports fan. He was a caring and compassionate person. While being treated for cancer at Dana Farber he spoke at many medical conferences, educating doctors and medical students about his experiences as a young adult living with cancer. His goal was to help doctors see the patient as a whole person, not just a disease. He also participated in many clinical trials hoping to advance the treatment of cancer for future patients.

His family requests that in lieu of flowers, donations in Ben’s memory be made to the Canary Foundation, 1501 S. California Avenue, Suite 2500, Palo Alto, CA 94304; Young Adult Program, Dana Farber, 44 Binney St., SW-411, Boston, MA 02115, Attn: Linda Carberry; or Congregation Kerem Shalom, P.O. Box 1646, Concord, MA 01742.