Response to C. Bosetti et al. (Trends in colorectal cancer mortality in Japan, 1970–2000)

✍ Scribed by Hoi Yan Yiu; Alice S. Whittemore; Atsuko Shibata

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: French
• Weight: 38 KB
• Volume: 113
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.20554

✦ Synopsis

Dear Sir,

We thank Bosetti et al. 1 for expanding the discussion of temporal trends in Japanese colorectal cancer rates prompted by our communication. 2 We noted increasing incidence rates in each successive birth cohort of Japanese (from those born in 1926 -1930 to those born in 1941-1945). Indeed, Japanese born after 1935 have had higher age-specific incidence rates than comparable cohorts of U.S. men and women, at least through the early 1990s.

These incidence trends are supported by the mortality trends indicated in Figure 1c of Bosetti et al. 1 (see p. 339). This graph shows rising death rates from 1970 -1990 among Japanese aged 45-64 years (the age group we examined). It is somewhat reassuring to see the suggestion in this graph that Japanese death rates subsequent to 1990 may be stabilizing. However, additional surveillance of future data will be needed to determine if this apparent stability continues.

In conclusion, we reiterate the concern raised by the cohortspecific incidence trends presented in our note: 2 namely, that colorectal cancer will become an increasing source of morbidity in Japan, as those in recent birth cohorts (e.g., those born after World War II) attain the ages of highest incidence.