He was survived by his wife and four children. " In the October 14, 1959, edition of Variety, it was reported that Lanza had planned to make his return to opera in the role of Canio in Leoncavallo's Pagliacci during the Rome Opera's 1960–61 season. He was fantastic!  His performance earned him compliments from the subject's son, Enrico Caruso Jr., a tenor in his own right. " Hollywood gossip columnist Hedda Hopper concluded that "there had never been anyone like Mario, and I doubt whether we shall ever see his like again". [Lanza] had an unusual, very unusual quality ... a tenor with a baritone color in the middle and lower registers, and a great feeling for the making of music. His exceptionally beautiful voice helps immeasurably." In 1991, his son Marc Lanza died of a heart attack. On October 7, Lanza died of an apparent pulmonary embolism at the age of 38. Music critic Jay C. Rosenfeld wrote in The New York Times of August 9, 1942, "Irma González as Mimì and Mario Lanza as Rodolfo were conspicuous by the beauty of their voices and the vividness of their characterizations." Had [Lanza] been already a leading tenor, if not the leading tenor at the Met[ropolitan Opera House], and come to Hollywood in between seasons to make a picture, he would have had [the security of having] the Met as his home," Green remarked. However the film was not as successful as his previous films, despite its strong musical content, including arias from Der Rosenkavalier, Fedora, L'arlesiana, and Otello, as well as the Act I duet from Otello with soprano Licia Albanese.
She adds that he was the "last of the great romantic performers".  However, as his biographers Cesari and Mannering have established, Lanza was not overweight at the beginning of the production, and it was, in fact, a disagreement with director Curtis Bernhardt over Lanza's singing of one of the songs in the film that led to Lanza walking off the set. I found it fascinating, musically, to work with [him]..
Prior to that, the adult Lanza had sung only two performances of an opera. The voice, the temperament, perfect diction. No autopsy was performed. He was besieged on cross-country concert tours and appearances years before Elvis Presley and The Beatles, was a true "superstar" before the word was invented and the first singer to ever earn gold records, with million sellers in both classical and popular categories. Conductor Peter Herman Adler, with whom Lanza previously had worked both in concert and on the soundtrack of The Great Caruso, visited the tenor in Rome during the summer of 1959 and later recalled that "[Lanza] was working two hours a day with an operatic coach, and intended to go back to opera, his only true love."  While at MGM, Lanza worked closely with the Academy Award-winning conductor, composer, and arranger Johnny Green. From January to April 1958, Lanza gave a concert tour of the UK, Belgium, the Netherlands, France and Germany. According to opera historian Clyde McCants, "Of all the Hollywood singers who performed operatic music .