New Movember-Funded Study

Intense doses of radiation may slow the progression of prostate cancer in some men whose disease has spread, according to a new Movember-funded study.
 
The results of a phase II clinical trial published today in the journal JAMA Oncology compared the effectiveness of a technique called stereotactic ablative radiation (SABR) with “wait and watch” observation in 54 men with oligometastatic prostate cancer.
 
Seven out 36 (19%) patients treated with SABR saw their disease progress, compared with 11 out of 18 participants (61%) undergoing observation alone.
 
The risk of developing new cancers at six months was also lower, occurring in 16% of those receiving SABR compared with 63% of those under observation.
 
Study leader Dr Phuoc Tran, professor of radiation oncology and molecular radiation sciences at the Johns Hopkins University School of Medicine and a member of the Johns Hopkins Kimmel Cancer Center, said: “It has been a longstanding question, especially important now in the era of immunotherapy, whether any type of radiation, and SABR specifically, can stimulate the immune system. Our trial offers the best data to date to suggest that SABR can cause a systemic immune response.”
 
Oligometastatic cancers are those that have spread from a primary tumour to between one and three sites outside the prostate gland.
 
Analysis of immune system white cells taken from the patients in the study indicated that SABR treatment was associated with an increased number of T cells, suggesting that the treatment stimulated a full-body immune system response to their cancers, according to Dr Tran. 
 
The research was supported by the Movember and the Prostate Cancer Foundation. Dr Mark Buzza, global director of prostate cancer biomedical research at Movember said: “We’re very excited by the results of the ORIOLE study which show that highly focussed doses of radiation therapy can not only slow the progression of prostate cancer, but may also induce an important immune response in men with oligometastatic prostate cancer.
 
“This has positive implications for the way that men with a small number of metastatic lesions will be more optimally treated, but also opens up exciting new opportunities to treat prostate cancer with a combination of radiation and immunotherapies in the future.”