The 200 wristbands were bought from the Lance Armstrong Foundation, which helps U.S. residents living with cancer, and were distributed to staff in the two cities, the Philadelphia Inquirer said Thursday.
"Good Morning America" co-anchor Charlie Gibson, a Jennings substitute, wore his wristband on Wednesday's broadcast.
Jennings, 66, announced his lung cancer condition last week and began outpatient chemotherapy treatment Wednesday. A date for his return has not been announced.
Boston schools pull out free condoms over wrapping complaints
NBC reportedly holds celebs hostage to Jimmy Fallon's show