内容紹介
Seasonal Variations in Breast Cancer Diagnosis in Osaka, Japan
Summary
To date, seasonal variations in breast cancer diagnosis have been reported in Western countries. In the present study, we calculated the number of breast cancer diagnoses according to season between 1976 and 2005, using data from the Osaka Cancer Registry. In all time periods and all age groups, breast cancer diagnosis showed peaks in early summer and troughs in winter. The number of breast cancer diagnoses in the spring, summer, autumn, and winter were 2,595(26%), 2,739(27%), 2,585(26%), and 2,120(21%)in 1976-1985; 4,219(26%), 4,581(28%), 4,262(26%), and 3,466(21%)in 1986-1995; and 6,299(25%), 6,852(28%), 6,368(26%), and 5,335(22%)in 1996-2005, respectively. Most cases were diagnosed because of an awareness of a breast mass. The trend in screening-detected cases differed from the overall trend. As screening becomes more widely adopted, these seasonal variations might change. Careful monitoring is needed to confirm these findings.
要旨
現在までに乳癌診断時期に季節変動があることが諸外国で報告されているが,本邦における報告はない。本研究では大阪府がん登録を用いて1976~2005年までの乳癌診断の季節変動を調査した。四季別の診断件数は,1976~1985年は春2,595例(26%),夏2,739例(27%),秋2,585例(26%),冬2,120例(21%),1986~1995年は春4,219例(26%),夏4,581例(28%),秋4,262例(26%),冬3,466例(21%),1996~2005年は春6,299例(25%),夏6,852例(28%),秋6,368例(26%),冬5,335例(22%)であった。すべての年齢階級,すべての罹患年で乳癌診断件数は初夏に多く,冬に少なかった。ほとんどの症例が症状を契機に発見されていた。乳癌検診の普及により,このような季節変動が今後置き換わっていく可能性がある。今後も慎重な観察が必要である。
目次
Summary
To date, seasonal variations in breast cancer diagnosis have been reported in Western countries. In the present study, we calculated the number of breast cancer diagnoses according to season between 1976 and 2005, using data from the Osaka Cancer Registry. In all time periods and all age groups, breast cancer diagnosis showed peaks in early summer and troughs in winter. The number of breast cancer diagnoses in the spring, summer, autumn, and winter were 2,595(26%), 2,739(27%), 2,585(26%), and 2,120(21%)in 1976-1985; 4,219(26%), 4,581(28%), 4,262(26%), and 3,466(21%)in 1986-1995; and 6,299(25%), 6,852(28%), 6,368(26%), and 5,335(22%)in 1996-2005, respectively. Most cases were diagnosed because of an awareness of a breast mass. The trend in screening-detected cases differed from the overall trend. As screening becomes more widely adopted, these seasonal variations might change. Careful monitoring is needed to confirm these findings.
要旨
現在までに乳癌診断時期に季節変動があることが諸外国で報告されているが,本邦における報告はない。本研究では大阪府がん登録を用いて1976~2005年までの乳癌診断の季節変動を調査した。四季別の診断件数は,1976~1985年は春2,595例(26%),夏2,739例(27%),秋2,585例(26%),冬2,120例(21%),1986~1995年は春4,219例(26%),夏4,581例(28%),秋4,262例(26%),冬3,466例(21%),1996~2005年は春6,299例(25%),夏6,852例(28%),秋6,368例(26%),冬5,335例(22%)であった。すべての年齢階級,すべての罹患年で乳癌診断件数は初夏に多く,冬に少なかった。ほとんどの症例が症状を契機に発見されていた。乳癌検診の普及により,このような季節変動が今後置き換わっていく可能性がある。今後も慎重な観察が必要である。