Incidence of prostate cancer (PCa) is reported to be increasing in Asia including Japan. Although this trend has been attributed partly to a more westernized diet, this assumption may involve variable confounders.
To have more insight, we examined histological features of contemporary versus historical latent PCa.
Prostatic specimens from a consecutive autopsy series (n=127, Present study, 2008 to 2013) were examined. Each prostatic gland was fixed and sliced in step-sections. The findings were compared to those from another autopsy series (n=501, Wada study, 1983 to 1987) at our institution.
The mean age of subjects in the Present study was 68. 9 years, while the mean age was not available from the original paper of Wada study. However, the mean age of the 566 entrants in the expanded database (1983-1989) was 63. 5 years (P=0. 0001). Prostatic weights were significantly higher in the Present study (P<0. 0001). Latent PCa was found more frequently in the Present study than Wada study (43. 3% and 20. 8%, respectively, P<0. 0001). No distinct difference was seen in the proportion of tumor grade between groups. Increasing trend of moderately to poorly-differentiated tumors with advancing age was more evident in the Present study. Index cancer volume was greater in the Present study; with 25. 5% measuring ≥500mm3, compared to only 9. 6% of cancers in Wada study (P=0. 008).
Chronological changes in histological characteristics of Japanese latent PCa were noted; it is more frequent and larger in the contemporary series. Our data may reflect a worldwide trend in the increasingly aging societies.
The Journal of urology. 2015 Dec 08 [Epub ahead of print]
Takahiro Kimura, Hiroyuki Takahashi, Mioko Okayasu, Masahito Kido, Hiroyuki Inaba, Hidetoshi Kuruma, Toshihiro Yamamoto, Bungo Furusato, Masakuni Furusato, Tetsuro Wada, Shin Egawa
Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. Department of Pathology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Pathology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Pathology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Pathology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan. , Department of Urology, Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan.