French President Francois Hollande has revealed he had treatment for a benign enlargement of the prostate, just over a year before he was elected.
Mr Hollande, 59, spent several days in hospital in February 2011, after which no further medical treatment was deemed necessary, a communique said.
Benign prostatic enlargement is a common condition in older men.
The state of health of French leaders is closely watched after past leaders hid grave illnesses while in office.
Georges Pompidou died in 1974 while still in office, after concealing the fact he was suffering from cancer.
Francois Mitterrand hid his prostate cancer for years while his successor, Jacques Chirac, suffered a stroke in 2005, three years after his re-election.
Last month French minister Dominique Bertinotti said she had been diagnosed with breast cancer eight months previously.
Since Mr Hollande was elected in May 2012, two official bulletins have been issued about the state of his health, the first that June and the second in March of this year.
According to Europe 1 radio, Mr Hollande spent a week in Cochin hospital in Paris, from 14 to 20 February. A month later, he declared his candidacy in the Socialist Party's presidential primaries.
"It would have been political suicide for him to make public any operation, let alone a prostate operation [at the time]," an unnamed source close to Mr Hollande told the radio.