Former US President Joe Biden has been diagnosed with an aggressive form of prostate cancer that spread across his bones.
Biden, 82, was diagnosed Friday after doctors discovered nodule in his prostate, his office said in a statement released Sunday.
The statement added that cancer had a “Gleason score of 9 (Grade Group 5)” on a scale of up to 10, indicating that Biden’s cancer is highly aggressive.
Here’s what you need to know about Biden’s diagnosis:
What is the Gleason Index?
Prostate cancer is confirmed through a biopsy. This is the procedure in which tissues are collected to check for signs of disease.
The Gleason Score, also known as the Gleason Index, is a grading system that evaluates the aggressive cancer of prostate cancer by examining the appearance of cancer cells under a microscope.
The pathologist examines the prostate tissue and assigns two Gleason grades. One is the most common pattern of cancer cells and the second common pattern.
Each grade drops between 1-5. Here we show tissues that resemble normal cells, with five representing the most abnormal appearance.
These two grades are added together to get a Gleason score in the range of 2-10. A 9 or 10 score is considered a highly aggressive form of cancer.
What is prostate cancer?
According to the National Cancer Institute (NCI), prostate cancer is ranked as the most frequently identified cancer among American men. Globally, it is the second most common form of cancer among men, and the fourth most common overall, according to the Global Cancer Research Fund.
This type of cancer affects the prostate, a small gland located near the male bladder, which contributes to the production of semen.
The exact cause remains unknown, but some evidence suggests that a fatty diet may be a contributing factor.
So far, over 313,000 new cases of prostate cancer have been diagnosed in the United States in 2025, NCI said on its website. This is 110,000 new cases, almost three times more than the second most common type of cancer among American male lung cancer. The United States has the highest number of recorded cases of prostate cancer worldwide.
According to the Centers for Disease Control and Prevention (CDC), 13 out of 100 American men suffer from illness, citing their age as the “most common risk factor.”
Symptoms include frequent urination, difficulty in urinating, burning heat during urination, and blood in semen and urine, the CDC said.
How will Biden be treated?
According to a statement from Biden’s office, “Cancer appears to be hormone sensitive and allows for effective management.”
“The president and his family are reviewing treatment options with his doctor,” he added.
Hormone-sensitive prostate cancer requires the growth of androgens, a male sex hormone group. Most of them are made from test circles.
The American Cancer Society points out that this particular type of prostate cancer can be treated using androgen ablation therapy, indicating that androgen levels “stop promoting the growth of prostate cancer cells.”
Johns Hopkins Medicine said the five-year survival rate for prostate cancer is nearly 100% after diagnosis, but it would drop to 28% if the cancer metastasizes as in Biden’s case.
They also point out that the survival rates for 10 and 15 years were 98% and 95%, respectively.
Patients have improved in recent decades, and patients can expect to live with metastatic prostate cancer, according to Matthew Smith, Matthew Smith of the Brigham Cancer Center in Massachusetts.
“It’s very treatable, but it’s not hard to cure,” Smith told The Associated Press.
“Most men in this situation are not advised to be treated with medication and either undergo surgery or radiation therapy.”
How do people respond to Biden’s diagnosis?
Longtime foe President Donald Trump, who lost Biden in the 2020 election, said in a post on his social media platform, Truth Social, that Biden wanted a “speech and successful recovery.”
Former President Barack Obama said his thoughts and prayers were with Biden, Obama’s vice president.
“No one can do this more to find a groundbreaking treatment for cancer in any form than Joe, and I’m sure he will fight this challenge with his trademark determination and grace,” Obama posted on X.
Michelle and I are thinking about the whole Biden family. I have never done anything more to find a groundbreaking treatment for cancer in all forms than Joe. He is confident that he will fight this challenge with the determination and grace of his trademark. I pray for a quick and complete recovery.
– Barack Obama (@barackobama) May 18, 2025
Kamala Harris, the 2024 Democratic presidential candidate and Biden’s vice president, said he was “sad” to hear Biden’s diagnosis.
“Joe is a fighter, and I know he will face this challenge with the same strength, resilience and optimism that has always defined his life and leadership,” Harris wrote on social media.
Former US Secretary of State and Sen. Hillary Rodham Clinton said “what Bidens thinks when they have cancer, they have a lot of illnesses to try to save other families.”
Biden’s eldest son, Beau, died of brain cancer in 2015 at the age of 46. After Beau’s death, in 2016, Obama attempted to speed up his research into cancer, making advances in the diagnosis, prevention and treatment of the disease.
Obama has appointed Biden to lead the initiative.