This may be superior to radiation following surgical removal of a testicle, according to researchers.
CHICAGO—The first randomized trial to evaluate the long-term outcome of a single dose of chemotherapy for early-stage testicular tumors suggests that this approach is safe and effective compared with radiation therapy, the current standard of care.
The study findings also showed that, after five years, patients receiving chemotherapy had a decreased risk of developing a tumor in the other testicle.
Lead investigator Tim Oliver, MD, professor emeritus of medical oncology at St. Bartholomew’s Hospital in London, said this study was the largest ever for testicular cancer. It included more than 1,400 men who had stage I seminoma and had surgery to remove the affected testicle.
The patients were randomized to receive either a single dose of chemotherapy (carboplatin) given over one hour on an outpatient basis (573 patients) or a course of daily radiation therapy given for two or three weeks (904 patients). The dose of carboplatin varied and was based on each man’s kidney function.
After five years, the rate of cancer recurrence was comparable in both arms. The researchers, who presented study findings here at the American Society of Clinical Oncology annual meeting, identified recurrence in 5% of the chemotherapy group and 4% of the radiation therapy group. With a median follow-up of 6.5 years, the carboplatin group was 78% less likely to develop a tumor in the remaining testicle compared with the radiation therapy group.
Fifteen patients in the radiation therapy arm developed a tumor in their remaining testicle compared with just two patients in the carboplatin arm. The adverse effects for both treatments were very low, but men treated with radiation therapy reported higher levels of moderate or severe lethargy (24% vs. 7% of patients receiving carboplatin) four weeks after starting treatment.
“Personal preference is becoming a more important factor in determining the best treatment for patients with testicular cancer,” Dr. Oliver said. “We’ve also seen this in prostate cancer, where there are a number of equally strong treatment options. This study establishes surgery followed by carboplatin chemotherapy as a safe new alternative for patients who have early-stage seminoma and would prefer a treatment that lasts a shorter period of time.”
The findings are particular significant because about half of all diagnosed testicular cancers are stage I seminoma, he said. Testicular cancer is the most common solid tumor diagnosed in men between the ages of 15 and 35 and there are about 8,000 new cases a year diagnosed in the United States alone, he noted.
“For the first time there is evidence for a minimum treatment of just one course of chemotherapy,” he said. “It is totally tolerable and there are very little side effects. More importantly, the study demonstrated a more powerful effect on chemoprevention on tumors in the other testicle.”