The Phantom makes an appearance in MAD Magazine number 56, published by E.C Publications, Inc. in USA in July 1960.
The MAD Magazine published as part of the regular series contains 52 black and white pages. It includes a 6 page parody story titled ‘The Mad “Comic” Opera’, written by Frank Jacobs and illustrated by Wallace Wood.
The comic strip story is based on a parody of a Broadway musicals using comic strip characters, with Rex Morgan kidnapping Annie and intends to remove her unique eyes, but Sandy leads Dick Tracy and Tarzan to a rescue, which is aided by the Phantom, Snuffy Smith and others.
The Phantom appears in 2 comic panels, as can be seen below.
Thank you Christopher Smith for assisting with images and information.
The Phantom 