Thomas Jefferson University Hospital - Jefferson urologic oncologist Edouard J. Trabulsi, MD, explains what these studies mean for individual patients

Jefferson urologic oncologist Edouard J. Trabulsi, MD, explains what these studies mean for individual patients

Edouard J. Trabulsi, MD

PSA is a protein produced by the prostate gland. A PSA test measures levels of PSA in the blood. It is normal for men to have low blood levels of PSA, but prostate cancer can increase PSA levels.

Two recent studies shed some light on the significance of changing PSA levels in men who have undergone treatment for prostate cancer.

The first study suggests that for men with prostate cancer, a rise in prostate-specific antigen (PSA) levels after radiation therapy – called PSA bounce – is not clinically relevant and does not affect survival.

The second study suggests that a rapidly rising PSA level before treatment is a sign that the cancer has most likely spread beyond the prostate and that the patient may need hormone therapy in addition to radiation.

In the following report, Jefferson urologic oncologist Edouard J. Trabulsi, MD, helps to interpret both studies and explains what they mean for individual patients. Dr. Trabulsi is Director of Minimally Invasive Urologic Oncology, as well as Director of Clinical Trials, in the Department of Urology, Jefferson Medical College at Thomas Jefferson University. He is also the Co-Director of the Genito-Urinary Multidisciplinary Cancer Clinic, Kimmel Cancer Center at Jefferson.

First study: Survival not affected by PSA bounce
In the first study, researchers sought to determine whether there was a difference in survival between men who had a PSA bounce after radiation therapy compared with men who did not.

The researchers collected data on more than 7,500 men treated either with external-beam radiation or with radioactive seed implants. They found that a significant number of men had at least one PSA bounce within one to three years after treatment. However, there were no differences in survival of patients who had a bounce and those who did not.

In the past, a PSA bounce was thought to mean that the cancer had returned and the patient needed hormone treatment – which Dr. Trabulsi says can have many short-term side effects, including hot flashes, erectile dysfunction and breast growth and/or tenderness, as well as long-term risks of osteoporosis, anemia, fatigue, mental status changes and weight gain.

"This large study offers reassurance that for the majority of men, a 'bounce' in PSA will decline on its own without further treatment," Dr. Trabulsi says.

But he is quick to add that on an individual basis, the study provides little guidance for the patient or his treating physician: "Experiencing PSA bounce can be very anxiety-provoking for a patient. Typically, the best course of action is careful observation through regular PSA checks."

Dr. Trabulsi says that when the PSA level continues to rise – without the typical decline seen in a PSA bounce scenario – the patient is experiencing PSA recurrence.

"At that point, the physician would likely institute further treatment, usually hormonal therapy," he notes, adding that this particular study failed to address the fundamental issue of separating PSA bounce and PSA recurrence.

Second study: PSAV test can determine cancer spread
In the second study, researchers collected data on 671 men with clinically localized prostate cancer who received 3-D conformal radiation therapy between 1989 and 1999.

The researchers found that the rate of rise in PSA levels – known as PSA velocity (PSAV) – can determine when prostate cancer may have already spread, even in men with clinically localized disease.

Men whose PSA is rising rapidly prior to treatment appear to be at higher risk for having disease outside of the prostate, which has been shown to be a risk factor for death from prostate cancer.

The research team found that when PSAV was greater than 2 nanograms per milliliter per year, PSA was likely to continue rising at the same rate despite radiation therapy. In addition, men with a rapidly rising PSAV were more likely to have a cancer spread beyond the prostate and a greater risk of dying from the disease. But, this relationship was not seen for men with a PSAV of less than 2 nanograms per milliliter per year.

"A very fast rise in PSA before the cancer is diagnosed indicates that there is a higher chance the cancer has escaped out of the prostate," Dr. Trabulsi explains. "Conversely, if the PSA rise was very slow leading up to the cancer diagnosis, then we would expect there is a lower chance of the cancer spreading."

The study's author suggests that men with a rapidly rising PSA need treatment to more than the prostate area and should strongly consider hormone therapy.

Dr. Trabulsi notes that this study is consistent with several other recent studies indicating that rate of increase of PSA before treatment is an important predictor of the response to treatment – and the risk of subsequent treatment failure and death from prostate cancer.

However, he disagrees with the study author's broad recommendation of hormone therapy. "That recommendation does not apply across the board – especially to men who are undergoing surgery for prostate cancer," he explains. "After years of investigation, the use of hormonal therapy before surgical therapy did not show an improvement in cure for prostate cancer."

Always consult your physician for more information. Make an appointment with a Jefferson physician online or by calling 1-800-JEFF-NOW.