Dr. David B. Samadi Explains Why PSA Is an Accurate Marker for Prostate Cancer

In a study published in the Journal of Biological Chemistry, researchers at Duke University have discovered that blood levels of prostate-specific antigen (PSA) rise as prostate cancer attacks the body. “The results suggests that the antibodies that interact with cancer cell receptors stimulate the production of PSA, which then stimulates more cancer growth,” said Dr. David B. Samadi, a prostate cancer treatment, robotic prostatectomy, and robotic surgery expert, who is also the Vice Chairman, Department of Urology, and Chief of Robotics and Minimally Invasive Surgery at The Mount Sinai Medical Center in New York City.

Researchers found that the alpha2-macroglobulin antibody reacts with a receptor called the GRP78, which creates PSA. “High PSA levels indicate that a man has prostate cancer,” said Dr. Samadi, a urologic oncologist who is also trained in laparoscopy and open traditional surgery. Further testing, such as a digital rectal exam, is usually needed to confirm the diagnosis. “However,” says Samadi, “Normal PSA levels do not necessarily mean that a patient does not have cancer — approximately 15 percent of men diagnosed with prostate cancer have normal PSA levels.”

The PSA test is the most useful measure of the risk of prostate cancer

The PSA test is known to be the most useful measure of the risk of prostate cancer in men. “Healthcare providers have always known there is a connection between elevated PSA levels and increased odds of developing prostate cancer, though the exact reasons behind this link were not clear until this study,” said Dr. Samadi, who’s performed over 3,100 successful robotic prostate surgeries in his practice. Duke University researchers discovered that tumors begin producing PSA in small quantities in the beginning, but then eventually, PSA proteins begin binding with antibodies to create a complex. This complex then starts feeding tumor growth. Once this happens, the cancer then grows and spreads.

“This discovery only further highlights the importance of PSA testing for men above a certain age,” said Dr. Samadi. “The PSA is still one of the most effective tools in fighting prostate cancer.” Samadi states that monitoring PSA fluctuations is vital for tracking prostate cancer. “A rise in PSA level of 0.25 in one year is definitely something to be concerned about,” said Samadi. “Therefore, the PSA can help doctors determine the prostate cancer treatment.”

In his practice, Dr. Samadi does not rely on the PSA test alone to determine a diagnosis of prostate cancer. He uses a combination of the PSA, DRE and Gleason scores, which help evaluate the prognosis of prostate cancer. “These are the markers I will have to rely on until science finds another superior to the PSA,” said Samadi. “However, as a standalone test, the PSA remains the best diagnostic tool for prostate cancer.”