Duquense University officials said they canceled an appearance by Geraldo Rivera because the U.S. journalist posted a semi-nude photo of himself online. Rivera had been booked to hosting a symposium in Pittsburgh on the 50th anniversary of the assassination of President John F. Kennedy. School officials said they found the photo \"inappropriate\" and rescinded their invitation, the Pittsburgh Tribune-Review reported. \"The administration felt that Mr. Rivera\'s decision to post a nearly naked picture of himself on social media was inappropriate and therefore withdrew the invitation,\" said Bridget Fare, assistant vice president for Public Affairs at Duquesne. \"Just heard Duquesne Univ cancelled my appearance at JFK assassination panel because of \'selfie\'. Fact I first aired Zapruder film less impt,\" Rivera said on Twitter Friday. Rivera made waves after posting a picture of himself shirtless with a towel around his waste, bragging about his physique on his 70th birthday. He would later admit he was drunk at the time he sent the tweet. The symposium, scheduled for Oct. 17-19, is expected to draw a high-level list of criminal pathologists and others involved in the investigation into Kennedy\'s assassination in Dallas and the evidence against Lee Harvey Oswald, identified in the Warren Commission\'s official report as the lone assassin of Kennedy in Dallas in 1963.