The 81-year-old, who was arrested in 2006 after 40 years on the run, during which he communicated with his lieutenants by word of mouth or typewritten notes, is serving several consecutive life sentences.
Provenzano's detention in solitary confinement was extended last month, while Italy's supreme court last week also rejected an appeal from his lawyers that he be released from prison due to ill-health.
"For the umpteenth time, his relatives and his defence lawyers are finding out news about Provenzano from the press," his lawyer Rosalba Di Gregorio is quoted as saying.
Nicknamed "The Tractor" for his propensity for violence and stubbornness, Provenzano became the uncontested head of Cosa Nostra after the incarceration of his predecessor Toto Riina in 1993.
Provenzano was Italy's most-wanted man for many years and his arrest in a farmhouse in his fiefdom in the Corleone region near Palermo was announced in 2006.
His death was announced prematurely several times – including when his wife and three children, who were also on the run, suddenly reappeared in Corleone in 1992.