Is prostate cancer sufficiently different in Japan and United States to justify using ADT differently in those two countries?

Trans-Pacific variation in outcomes for men treated with primary androgen deprivation therapy for prostate cancer. By Cooperberg et al. 2014

 

Key sentence from the paper: “… men treated in Japan tend to be diagnosed at older ages and with higher risk and more advanced tumors than men treated in the U.S. However, cancer-specific and overall survival were substantially better for men treated in Japan compared to men treated in the U.S., even after adjusting for disease risk, patient characteristics, and type of ADT.

 

For the full abstract, see: http://www.ncbi.nlm.nih.gov/pubmed/25238114  

 

Commentary: Back in July, we blogged the 2014 Lu-Yao et al paper which suggested that early use of ADT upon biochemical failure may offer no survival advantage over late use of that treatment. It turns out that the problem is more complicated when you start to consider ethnic and lifestyle (diet) differences.

In North America, the current recommendation is not to use ADT as a primary (=early) therapy. In Japan, however, it is a standard practice. This paper looks at prostate cancer patients in both Japan and North America to see whether the recommendation makes sense for their particular populations. What the authors found is quite remarkable. The national recommendations seems to be appropriate for the two different populations. The authors go on to suggest that it is differences in genetic, diet and environmental exposure that probably account for the difference in how prostate cancer presents in the two countries and how the patients respond to ADT. Another quote from the paper is that “ADT appears to be better tolerated in Japan—in terms of bone loss, cardiovascular risks, and other factors—than in Western populations.

 

Cooperberg MR, Hinotsu S, Namiki M, Carroll PR, Akaza H. 2014. Trans-Pacific Variation in Outcomes for Men Treated With Primary Androgen Deprivation Therapy for Prostate Cancer. BJU International. 19 September 2014 [Epub ahead of print]