A blood sample is marked to indicate high levels of prostate-specific antigen, which may be a sign of prostate cancer. (Getty Images/iStockphoto)

Experts say men concerned about prostate cancer should discuss getting screened for the disease, which is both the second most common type of cancer in men in the United States and the second highest cause of cancer deaths among them.

Maryland Senate President Thomas V. Mike Miller Jr., 76, announced Thursday that he was receiving chemotherapy for metastasized prostate cancer that was diagnosed in July and not halted by earlier treatments.

Prostate cancer can be slow-growing and may not need treatment, or it can be aggressive; the key is diagnosing the cancer early and determining which type it is, said Keith Kowalczyk, director of urologic oncology at MedStar Georgetown University Hospital.

A prostate-specific antigen (PSA) test, used to determine the level of a specific protein made by the prostate gland, often is used as a screening tool. If the PSA level is high, doctors may opt to physically examine the gland for abnormalities or take biopsies to look for cancer cells. Cancer can cause PSA levels to rise — but so can prostate infections and old age, making the test only one tool in leading doctors to a diagnosis.

“An open conversation with the primary care practitioner is the best way forward,” said Christopher Sweeney, a medical oncologist at the Dana-Farber Cancer Institute in Boston. “What we can do to prevent death is treat it when it needs to be treated . . . but not all prostate cancer needs to be treated.”

One in nine men will get a diagnosis of prostate cancer during their lives, with about 60 percent of those diagnoses occurring in men 65 and older, according to the American Cancer Society.

Most don’t die of the disease, according to the group, but survival rates are usually higher for men whose cancer is detected in the early stages. The leading cause of cancer deaths in men in the United States is lung cancer.

“There are so many different treatments that really depend on the patient’s age, how healthy they are, what stage or grade is the cancer, how serious is the cancer,” Kowalczyk said. “We’re good at treating cancer if we find it early.”