Radiation After Prostatectomy Keeps Some Patients Disease Free Longer

August 1, 1995

Prostate cancer patients who have an elevated prostate-specific antigen (PSA) blood test after surgery need radiation therapy

Prostate cancer patients who have an elevated prostate-specificantigen (PSA) blood test after surgery need radiation therapy,preferably before their PSA reaches a level of 1 ng/mL, accordingto a new study.

The study reviewed 51 patients who had been treated with radiationtherapy following a radical prostatectomy, said Dr. David Koeplin,a radiation oncologist at the University of California, San Francisco.Some 90% of the patients had disease that had spread beyond theprostate, he said. Patients with more advanced disease are morelikely to have a detectable PSA level after surgery, added Dr.Koeplin.

Most of the patients (73%) who were treated with radiation therapybefore the postoperative PSA reached a level of 1 ng/mL remainedclinically and biochemically free of disease 4 years after surgery.This compares to 38% of patients who were treated with radiationafter PSA levels rose to between 1 and 10 ng/mL, Dr. Koeplin toldthe American Radium Society at its annual meeting in Paris.

None of the patients with a PSA level of 10 ng/mL or more at thetime of radiation was cured of his disease, said Dr. Koeplin.

"An elevated PSA level after surgery tells us how we havedone and if we need to do more for these patients. Our study showsthat patients with evidence of residual disease following surgerycan be helped by radiation therapy. "We're more likely tohelp them the sooner we find out cancer remains," he said.An elevated PSA, in many instances, is the earliest indicationthat cancer is still present, Dr. Koeplin added.

The bottom line is that a lot of men who have surgery also needradiation therapy but aren't receiving it, he said. We need tocarefully monitor all prostate cancer patients who have had surgery,and if they have a detectable PSA level, they most likely needradiation therapy," he contended.