Japan prostate cancer

In countries such as Japan, although the incidence of latent, small or non-infiltrative prostate cancer is similar to that found in Western countries, the incidence of invasive cancer and associated mortality is far lower (Adlercreutz and Mazur, 1997). In Japan, diets have traditionally included large amounts of soy, and it has been proposed that this may be responsible for the protective effect. To date, however, the results are inconsistent, although there may be an inverse correlation with non-fermented soy foods. The active component... 

The parenteral formulation diethylstilbestrol diphosphate is less commonly used than the oral formulation. In Japan, 24 elderly patients with advanced relapsed prostatic cancer were treated with high doses supplemented with ethi-nylestradiol (doses unclear) there was some slight therapeutic effect, but there were gastrointestinal symptoms and fluid retention (48). Also in Japan, a few patients with advanced disease were treated using intravenous diethylstilbestrol diphosphate 500 mg/day for 20 consecutive days to a total dose of 10 g the authors conclusion was more positive but adverse events were not specified (49). 

The study on prostate cancer (Table 20.7) found no association between prostate cancer risk with any of the analyzed flavonoids [Bosetti et al., 2006]. Although some flavonoids showed a favorable effect against prostate cancer [Magee and Rowland, 2004], the results from epidemiological studies are inconsistent. A recent prospective study from Japan found that isoflavone... 

In Japan mortality from cancer of the prostate is lower than in Western countries. A number of other groups and nationahties also have a low risk of developing this type of cancer, e.g. Seventh Day Adventists who eat a lot of pulses (peas, beans, lentils) had plasma levels of testosterone and 17 j -oestradiol which were significantly lower than those who did not consume diets rich in these compounds as well as having a significantly decreased incidence of prostate cancer. Hawaiians of Japanese ancestry who eat rice and tofu (a soybean product) also have a lower risk of developing this cancer. 

Genetic make-up is certainly a factor that predisposes an individual to cancer - a familial pattern of breast cancer is, for example, well-established. However, an additive and even predominant environmental effect is clearly evident when one studies migrant populations. In Japan, the incidence of stomach cancer is high, probably due to a high consumption of salted fish and pickled foods but the incidence of prostate cancer is low, perhaps because this has an association with the consumption of large amounts of red meat. However, in migrant Japanese communities in the USA, the incidence of these two cancers more closely mirrors that of the native US population, suggesting that the adopted US diet has affected their predisposition to the two cancers. In addition, black Americans have similar incidences of the main cancers to white Americans, but these differ markedly from those seen in black Africans. 

Kurahashi, N., Iwasaki, M., Inoue, M., Sasazuki, S., and Tsugane, S. 2008. Plasma isoflavones and subsequent risk of prostate cancer in a nested case-control study the Japan Public Health... 

Ozasa, K., Nakao, M., Watanabe, Y., Hayashi, K., Miki, T., Mikami, K., Mori, M., Sakauchi, F., Washio, M., Ito, Y., Suzuki, K., Wakai, K., and Tamakoshi, A. 2004. Serum phytoestrogens and prostate cancer risk in a nested case-control study among Japanes men. Cancer Sci. 95, 65 71. 

Sonoda, T., Nagata, Y., Mori, M., Miyanaga, N., Takashima, N., Okumura, K., Goto, K., Naito, S., Fujimoto, K., Hirao, Y., Takahashi, A., Tsukamoto, T., Fujioka, T., and Akaza, H. 2004. A case-control study of diet and prostate cancer in Japan possible protective effect of traditional Japanes diet. Cancer Sci. 95, 238-242. 

Both breast and prostate cancer are rare in China and Japan compared with the... 

Figure 7.3 Cancer of the breast and prostate in Chinese andJapanese immigrants to the USA compared with incidence of the diseases in first-degree relatives in China and Japan and the local population in the USA (SFO, San Francisco), From data reported by Haenzel W and Kurihawa M (1965) Journal of the National Cancer Institute 40 43-68, andYu H et al. (1991) International Journal of Epidemiology 20.- 76-81. 

It is noteworthy that in Japan, where the traditional diet contains relatively large amounts of phyto-oestrogens from soya bean products, there is a low incidence of cancer of the breast and prostate, as well as an unexpectedly low incidence of osteoporosis (despite the lower peak bone density of Japanese women compared with European or American women see section 11.15.1.1). Although some prospective and case—control studies show a protective effect of soya bean consumption with respect to breast cancer, others do not. 

---