Milton Berle hosted a "telethon" in 1949 for the Damon Runyon cancer fund. Jerry Lewis would later popularize the "telethon" for muscular dystrophy.
(Oxford English Dictionary)
orig. and chiefly U.S.
An especially prolonged television programme used to raise money for a charity or cause; also in extended use, a lengthy television programme for some other purpose.
1949 Examiner (San Francisco) 10 Apr. 22/5 'Telethon' nets $702,000.
11 April 1949, New York Times, pg. 42:
Milton Berle's sixteen-hour "telethon," which ended at 4 A. M. yesterday, netted more than $1,100,000 in pledges for the Damon Runyon Memorial Fund for cancer research, NBC has reported. The telecast, which was staged from NBC television's International Theatre in Columbus Circle, showed Berle interviewing stage, screen and television personalities between periods of mugging, pleading and cajoling his audience to contribute to the fund. At its conclusion, Niles Trammell, NBC president, said that it was the longest telecast ever made.
Berle sat before a battery of nine telephones at the theatre picking up calls that were relayed to him by changing shifts of models and show girls, as well as by volunteers from the United Parents Association.
9 March 1951, Washington Post, "Walter Winchell in New York," pg. B13:
If Milton Berle's annual telethon for the Runyon Fund brings in $300,000, we will have our first $5,000,000.