Former US President Joe Biden has been diagnosed with an "aggressive" form of prostate cancer that has spread to his bones. He is currently considering treatment options, AFP reports.

On Friday, the 82-year-old Democrat was "diagnosed with prostate cancer ... with metastasis to bone," his office said in a statement.

"Although this represents a more aggressive form of the disease, the cancer appears to be hormone sensitive, allowing for effective treatment. The president and his family are reviewing treatment options with his doctors," the statement added.

The diagnosis was made after Biden had been experiencing increasing symptoms when urinating and was examined last week for a new prostate nodule discovery.

The announcement comes at a time when the Democrat claims he could have won the 2024 presidential election after dropping out of the race due to age and ability issues.

Last week, a newly released recording of Biden speaking haltingly and struggling to recall key events and dates fueled renewed debate about his mental abilities while still in office.

Biden's son, Beau Biden, died of brain cancer in 2015 | BGNES

His vice presidential running mate Kamala Harris ultimately lost to Republican Donald Trump.