In Turin, the hub of the Fiat empire, the announcement was greeted with shock. A day after part of the city's cathedral went up in flames, the future of its other leading institution looked uncertain: Giovanni Alberto, 33, (pictured), is the only member of the family's younger generation being groomed to take over as head of Italy's largest private company.
Agnelli jnr seemed confident he could beat the disease, for which he is being treated at New York's Sloan Kettering Memorial Cancer Center: "I should be back on my feet by the end of summer." His uncle Gianni, the Fiat chief, who designated Agnelli jnr his successor in 1995, said: "He's a strong lad, and he's prepared to fight it. But the cure's going to be painful."
Giovanni Alberto admitted treatment for his form of cancer, which he did not name, was lengthy and difficult, and would keep him away from Italy for "a long period".
He has set up an office in New York and intends to remain involved in running his company, Piaggio, makers of the Vespa scooter.
Agnelli jnr was Italy's most eligible bachelor until five months, ago when he married Avery Howe, an architect.
Often called "Italy's John-John Kennedy", his private life has received similar attention from the world's popular press.
A British tabloid announced his imminent divorce in an April Fool's joke this year. Anne HanleyReuse content