CHICAGO — Many men with prostate cancer put off using chemotherapy as long as possible, fearing its side effects.
But a new study has found that men given chemotherapy early in their treatment for advanced disease lived a median of nearly 14 months longer than those who did not get early chemotherapy. The result could upend the established treatment practice, researchers said Sunday.
Dr. Christopher Sweeney of the Dana-Farber Cancer Insitute in Boston, who led the study, said the results represented one of the biggest improvements ever seen in survival rates for adults with cancer that has spread widely from its original site.
Sweeney presented the results Sunday at the annual conference of the American Society of Clinical Oncology in Chicago.
“We haven’t seen survival benefits like that for any therapy in prostate cancer,” said Dr. Michael J. Morris, an associate professor at the Memorial Sloan-Kettering Cancer Center, who was not involved in the study but was selected to publicly comment on it at the meeting.
Another study presented Sunday found that drugs called aromatase inhibitors might be better than the standard drug tamoxifen in preventing a recurrence of disease in premenopausal women with early breast cancer.
Both studies were featured in the plenary session Sunday, meaning they were deemed among the most noteworthy of the more than 5,000 studies presented at the meeting.
In a conference that typically celebrates the latest and greatest drug, all four studies chosen for the plenary session this year are about better ways of using older drugs, showing that there can be a lot to learn even after drugs get to market.
Dr. Nicholas J. Vogelzang, an author of the study on prostate cancer, said that the findings would change practice and that he had already started discussing this option with patients. The challenge, he said, is getting men to agree.
“Not many of them want to do chemotherapy, even though the numbers are convincing,” said Vogelzang, who works at the Comprehensive Cancer Centers of Nevada.
The study’s findings apply to a fairly narrow group of patients — men whose cancer has already spread beyond the prostate gland at the time of diagnosis, or whose cancer has come back after surgery or radiation treatment and still remains susceptible to hormone therapy.
In the United States, about 240,000 new cases of prostate cancer are diagnosed each year. Only a small fraction of men have metastatic prostate cancer at the time of the initial diagnosis because prostate cancer screening using a blood test typically detects the disease before it has spread to bones or other organs.
But screening is expected to become less common because a government advisory committee, the US Preventive Services Task Force, has recommended against routine screening, saying that more men are harmed by unnecessary treatments for prostate cancer than are saved from death by screening. That could lead to an increase in men whose initial diagnosis is metastatic cancer, Vogelzang said.
The study, sponsored by the National Cancer Institute, involved 790 men who received either hormone therapy only or hormone therapy in addition to at most six infusions of docetaxel spaced three weeks apart.
Those who received the chemotherapy lived a median of 57.6 months, compared with 44.0 months in the control group, a difference of 13.6 months. The difference in survival was even greater — 17 months — for the patients whose cancer had spread more extensively. Morris of Sloan-Kettering said those men were the best candidates for early chemotherapy.
Docetaxel is sold under the brand name Taxotere by Sanofi, but generic versions are also available. Generic docetaxel costs about $1,500 or less per infusion. That’s far less than some other cancer drugs, which can exceed $100,000 for a course of treatment.
Docetaxel was approved for metastatic prostate cancer in 2004.
In the last few years, several other drugs have been approved, like Zytiga from Johnson & Johnson and Xtandi from Medivation and Astellas Pharma.