(RxWiki News) Although most men who have their prostate removed to treat prostate cancer stay disease free, some have a recurrence. Radiation following the surgery appears to reduce the chance of the cancer returning.
Men with high-risk prostate cancer who receive radiation treatment after a prostatectomy (removal of prostate) have a slower rise in cancer markers compared to those who do not receive radiation.
These markers can signal a return of the disease. While radiation appeared to keep down PSA levels, overall survival rates between groups were not significantly different.
"Look into radiation therapy."
Dr. Michel Bolla, MD, in the department of radiation oncology at the Centre Hospitalier Universitaire A Michallon in Grenoble, France, and his colleagues studied the PSA levels of 1005 men who received a prostatectomy to treat prostate cancer.
The American Cancer Society (ACS) estimates that more than 240,000 men will be diagnosed with prostate cancer in the US in 2012. According to the ACS, prostate cancer occurs mainly in older men.
Nearly two-thirds of cases are diagnosed in men aged 65 or older, and it is rare before age 40. The average age at the time of diagnosis is about 67.
Radical prostatectomy can be very effective in eliminating cancer. In this operation, the surgeon removes the entire prostate gland plus some of the tissue around it, including the seminal vesicles.
PSA stands for prostate specific antigen, a protein produced by prostate gland cells. PSA levels can be measured through blood samples. Scientists refer to a rise in these antigen levels as biochemical progression.
When PSA levels, or biochemical progression rates, are high, it can be—but is not necessarily—a sign of prostate cancer growth.
Researchers in this study randomly assigned 502 men to a group that received radiation therapy after the surgery and 503 men to a wait-and-see group, which did not receive radiation. Patients were age 75 or younger and had cancer that had spread beyond the prostate.
After a median of 10.6 years, investigators found that 311 in the wait-and-see group had PSA levels that rose compared with 198 patients in the radiation group.
The biochemical progression rate was 62 percent for the wait-and-see group vs. 39 percent for for those who had received post-surgery treatment.
Investigators noted that younger patients benefited more from the radiation compared with older patients.
Also, there was greater benefit for those with clear surgical margins (a clear edge between normal tissue and cancerous tissue) compared with those who had tumor cells remaining.
"Our results suggest that postoperative irradiation significantly improves biochemical progression-free survival [the chance of staying free of disease progression], and might improve clinical progression-free survival in patients younger than 70 years and those with positive surgical margins, although it might have a possible detrimental effect in patients aged 70 years or older," stated the authors in their published work.
The study was published on October 19 in The Lancet. Funding was provided by Ligue Nationale contre le Cancer (Comité de l'Isère, Grenoble, France) and the European Organisation for Research and Treatment of Cancer (EORTC) Charitable Trust.
