By Brenda Goodman, CNN

(CNN) — US Defense Secretary Lloyd Austin had surgery to treat prostate cancer in late December and later developed complications that landed him in intensive care, doctors at Walter Reed National Military Medical Center said Tuesday. But his own team and independent medical experts agree that his outlook is good.

His doctors say Austin, 70, was readmitted to the hospital on New Year’s Day after having minimally invasive surgery December 22 to remove prostate cancer, called a prostatectomy. He was admitted to intensive care January 2 after additional evaluation found a buildup of fluid that was impairing the function of his small intestines.

The fluid was drained, and his doctors says he is on the mend.

“He continues to make progress and we anticipate a full recovery although this can be a slow process,” the statement says.

Prostate cancer is the second most common cancer in men in the United States, behind non-melanoma skin cancers. About 13% – or 1 in 8 – American men will be diagnosed with prostate cancer in their lifetime, and about 2.5% – or 1 in 41 – will die from it, according to the National Cancer Institute.

Prostate cancer is riskier for Black men

But the risk of prostate cancer is not spread equally, said Dr. William Dahut, chief scientific officer for the American Cancer Society.

Black men are 70% more likely to be diagnosed with prostate cancer than White men and are more than twice as likely to die from the disease.

“It’s a greater incidence but also a much greater mortality,” Dahut said. “So generally, around the age of 40, Black men should talk to their physicians about screening.”

Most prostate cancers grow very slowly. It typically takes at least 10 years for a tumor confined to the prostate to cause significant symptoms.

A recent study confirmed that many men with the disease can be safely followed with regular medical tests and may not ever need to have harsh treatments like surgery, radiation or hormone blockers, without harming their chances of survival.

“About half of men who are diagnosed with prostate cancer can be watched and will never need to be treated because, yes, they have cancer, but it’s not aggressive, and it’s not going to kill them,” said Dr. Otis Brawley, a professor of oncology at Johns Hopkins University School of Medicine.

But, he adds, the decision to treat or to watch and wait is always a highly personal one.

“Tomorrow, I’m going to tell three different men, ‘You have prostate cancer. I would prefer we watch it, but it’s OK to get surgery. It’s also OK to get radiation,’ ” Brawley said. He also tells some men that they need surgery or radiation but that he wouldn’t sit back and watch under their circumstances.

“We don’t know where [Austin] falls on that spectrum,” he said.

Cancer survival after surgery is high

It’s reassuring that Austin’s cancer was detected by a blood test and that he had surgery to remove it, said Dr. Oliver Sartor, chief of the Genitourinary Cancer Disease Group at the Mayo Clinic.

“The worst prostate cancers are the ones that have spread and that you don’t operate on,” Sartor said. “So the fact that he was operated on, to me, is a relatively good sign.”

If prostate cancer is caught after the cancer has metastasized, or spread, the likelihood of surviving at least five years after diagnosis drops to 32%, according to ZeroCancer.org. But prostate cancer has a nearly 100% five-year survival rate if it is caught in its earliest stages.

Sartor said the type of surgery that Austin had – to remove his prostate – substantially cuts his risk of dying within the next five years.

“It’s probably 1% or less. It’s very, very rare for somebody who’s had their prostate operated on to die within the next five years,” Sartor said.

However, prostate cancer is known to be more aggressive in African American men, Sartor said, which may be why Austin chose to have surgery.

Prostate surgery complications like Austin’s are “extremely rare,” said Dr. Michael Stifelman, chief of urology at Hackensack University Medical Center in New Jersey. He said they happen in about 2% of surgical cases.

The fluid buildup described by Austin’s doctors can happen several ways, he said.

During a prostatectomy, doctors have to cut and then rejoin the urethra, the tube that carries urine from the bladder out of the body. “If that reconnecting of the bladder back to the urethra is not perfect, sometimes urine can leak out of the body and go into the abdomen,” Stifelman said.

Another way fluid might build up is after surgeons remove lymph nodes, glands that sit near the prostate and clean the blood. If those lymph nodes are not sealed completely after surgery, “sometimes you can have what’s called a lymphatic leak,” Stifelman said.

Finally, anytime tissue is removed in the body, fluid can leak and cause a buildup called a seroma.

All three of these would heal over time, Stifelman said.

“He can expect a full recovery,” Stifelman said.

CNN’s Jacqueline Howard contributed to this report.