KISS have postponed their upcoming concert in Salt Lake City, Utah as Gene Simmons has revealed he will be undergoing a medical procedure that "must be taken care of now," assuring fans they needn't worry.

The Sept. 14 gig is the band's last scheduled performance until November, as they continue to bid farewell to their fans around the globe. In a tweet, Simmons lamented not being able to play for the KISS fans in Utah, thanking them for their support.

"Apologies to the fans in Salt Lake City. We will come back and do the show at a later date," said the "Demon," who went on, "The truth is, I have to fly to LA to do a medical procedure. Nothing serious. But it must be taken care of now. Thank you for your good wishes. All is well."

Prior to the start of KISS' "The End of the Road" tour, Simmons promised that the band would stay on the road for three years before taking their final bow. Since the trek launched in January, they've played nearly 100 shows, with more to come in Australia and Japan before the year's end.

The end of touring also has fans wondering if it will mean the end of KISS completely or if they will continue to release new music. They haven't released a new record since 2012's Monster with both Paul Stanley and Simmons expressing apprehension given the current climate of album sales.

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