Results of a new clinical trial showed that men with untreatable prostate cancer may halt the spread of the disease and live longer though immunotherapy treatment.
Immunotherapy For Prostate Cancer
In the study involving 258 men with an advanced form of prostate cancer, researchers found that men lived much longer when they were treated with the immunotherapy drug pembrolizumab.
Immunotherapy drugs work by stimulating the body's immune system so it can recognise and fight cancer.
Earlier trials on using immunotherapy in prostate cancer have been unsuccessful. The latest trial, results of which were presented this weekend at the American Society of Clinical Oncology Meeting in Chicago, examined the genetics of tumors and found that certain groups of prostate cancer patients may benefit from the treatment.
About 38 percent of those who used the drug marketed by Merck as Keytruda were still alive after a year on the treatment. The drug also stopped cancer growth in 11 percent of the patients.
The researchers also said that some of the patients who had substantial responses to the treatment have tumors that may have mutations in the genes that control DNA repair, an important cellular process that maintains the genome.
Functional DNA repair constantly works in every cell of the body to fix damage, much of which happens during cell division. The amount of damage that a cell can endure, however, is influenced by external factors such as alcohol, smoking, exposure to UV light, and many cancer cells have lost some of the ability to self-repair the genome.
"Our study has found that immunotherapy can benefit a subset of men with advanced, otherwise untreatable prostate cancer, and these are most likely to include patients who have specific DNA repair mutations within their tumours," said Johann de Bono, Director of the Drug Development Unit at the Institute of Cancer Research.
De Bono said that while patients with DNA repair mutations responded to treatment, further investigation is still needed to confirm this.
Unwanted Side Effects Of Extreme Prostate Cancer Treatments
Prostate cancer is the third most common type of cancer in the United States. About 164,690 men are diagnosed of the disease per year. Prostate cancer is treated in a number of ways, but the more extreme treatments which include surgical interventions may cause physical and psychological side effects.
If patients who can respond to immunotherapy are identified, some of them may be able to avoid treatments that come with unwanted side effects.
