Former United States President Joe Biden has been diagnosed with an “aggressive” form of prostate cancer that has spread to his bones, and is reviewing treatment options.

On Friday, the 82-year-old Democrat — whose son Beau Biden died of cancer in 2015 — was diagnosed with the disease after he experienced urinary symptoms and a prostate nodule was found, a statement from his office said.

“While this represents a more aggressive form of the disease, the cancer appears to be hormone-sensitive which allows for effective management. The President and his family are reviewing treatment options with his physicians,” it continued.

US President Donald Trump, who has long derided political rival Biden over his cognitive abilities, said he was “saddened” by the news.

“We extend our warmest and best wishes to Jill and the family, and we wish Joe a fast and successful recovery,” Republican Trump said on Truth Social, referring to Biden’s wife, Jill Biden. 

“Joe is a fighter,” Biden’s vice president, Kamala Harris, who stepped in as Democratic nominee in the battle against Trump after Biden dropped out of last year’s presidential election, said in a post on X. 

“I know he will face this challenge with the same strength, resilience, and optimism that have always defined his life and leadership. We are hopeful for a full and speedy recovery,” she continued.

Prostate cancer is the most common form of cancer in men, with the American Cancer Society reporting one in eight men in the United States are diagnosed with it over their lifetime.

While it is highly treatable if discovered early, it is the second leading cause of cancer death in men, the organization said.

Hormone therapy is a common treatment that can shrink tumors and slow cancer growth, but is not a cure. 

According to the statement, Biden’s cancer was found to have “a Gleason score of 9 (Grade Group 5).”

Prostate cancer that looks “very abnormal” is assigned the highest rating, Grade 5, according to the American Cancer Society. The Gleason Score goes up to 10, indicating the seriousness of Biden’s disease.

Biden left office in January this year as the oldest serving US president in history, and was dogged by questions, including from Democratic voters, over his health and age for much of his term — and whether he could handle the office’s demands. 

His response was a brisk: “Watch me.”

In July last year, he was forced to drop his reelection bid after a disastrous debate against Trump in which fears about his decline and cognitive abilities came surging to the fore. 

Support rocketed for Harris as she stepped up to the plate, but she eventually lost to Trump. 

Biden, who beat Trump at the polls in 2020, maintains that he could have won the 2024 election too, but questions have long swirled over the responses of staff and key Democrats to his decline.

They have flared with the upcoming release of a new book on his “disastrous” choice to run again, and the publication last week of a recording of him speaking hesitantly and struggling to recall key events and dates. 

Biden’s life has been marked by personal tragedy. In 1972, his first wife and baby daughter were killed in a car crash.  

His son Beau Biden died aged 46 of an aggressive form of brain cancer in 2015, a loss which touched many Americans.

In the wake of Beau Biden’s death, then-president Barack Obama launched a “cancer moonshot” bid to corral the disease in the United States, tasking Biden, then his vice president, with leading the effort. 

“It’s personal for me,” Biden said at the time.

“But it’s also personal for nearly every American, and millions of people around the world. We all know someone who has had cancer, or is fighting to beat it.”