Doctors first looked to Dayhoff's family members because close relatives have the best chance of matching a victim's bone marrow. A match could not be found and the search for a donor for Dayhoff was expanded to the National Marrow Donor Program.
"When I was diagnosed with leukemia in 1991, an anxious process for my family and me was just beginning," Dayhoff wrote in his letter.
"The blood laboratory work, the bone marrow aspirations, the chemotherapies and all the related issues that went along with diagnosis were stressful," Dayhoff wrote.
Friends say Dayhoff was never able to find a donor.
While Dayhoff was struggling with the disease, he was trying to raise awareness for leukemia victims.
He helped organize the Relay for Life event last May at Williamsport High School to raise money for the local chapter of the American Cancer Society.
Participants contributed money to the fund raiser by sponsoring people who either walked or jogged laps around the high school.
During the event, which ran through the night, luminaires were placed around the track as memorials to cancer victims.
"It was very, very moving," said Stuart Mullendore, a close friend of Dayhoff's.
"He was just an incredible young man," said William J. Reuter, president of Farmers and Merchants Bank and Trust in Hagerstown.
Dayhoff was vice president of branch administration for the local bank.
Dayhoff received a bachelor's degree from Western Maryland College and was a graduate of the Graduate School of Banking at Rutgers University and the University of Maryland Banking School. He also received a master's degree in business administration from Hood College.