Dr. David Shusterman, a board-certified urological surgeon and instructor in urology, said during an appearance on NewsNation that former President Joe Biden may have been living with cancer for “five to ten years,” based on the nature of his diagnosis, meaning his administration was likely aware of the issue but didn’t reveal it to the country – the same as hiding his mental decline.

Biden was diagnosed with prostate cancer on Friday, according to a statement released Sunday by his personal office.

The statement describes the cancer as “a more aggressive form of the disease” that has spread to the bone, though it notes that the condition can be effectively managed, but also that the Biden family is “weighing treatment options.”

The diagnosis comes amid growing scrutiny over Biden’s physical and mental decline—and allegations of a cover-up—just days before the release of “Original Sin,” a book by CNN anchor Jake Tapper and Axios reporter Alex Thompson.

“I have to say that in my expertise as a urologist, prostate cancer like this doesn’t come on just overnight. This happens over a long period of time. And typically you would see a PSA elevation, you would do a biopsy, and then you would do a treatment for the prostate cancer,” Shusterman told NewsNation.

“Then after the prostate cancer is treated, it can actually get worse and spread to different parts of the body. And so it’s very unlikely that someone could get annual checkups and not notice a PSA elevation over the past,” he added.

Shusterman then recalled his experience working in VA hospitals, stating that Biden’s diagnosis is consistent any patient who “hasn’t had medical attention in 10 years, presents to an emergency room with bone pain, and then they find that it’s metastatic prostate cancer.”

He continued: “But in the modern age of medicine, especially the fact that he was a former president, he had intensive state-of-the-art care where we can see prostate cancer 10 years in the past. So this is, I mean, it’s very unusual to hear that someone has prostate cancer where they’re annually being followed up.”

He was then asked whether he was suggesting that Biden was battling cancer while he was serving in the Oval Office.

“Well, most likely he had prostate cancer for a long time and aggressive prostate cancers such as this at age 80 grows over a long period of time. I mean usually it takes from the first diagnosis of prostate cancer to the to spread would take five to ten years even in the most aggressive form,” he said.

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