TY - JOUR
T1 - Stage-specific incidence of breast cancer before the beginning of organized screening programs in Italy
AU - Buiatti, Eva
AU - Barchielli, Alessandro
AU - Bartolacci, Simone
AU - Bucchi, Lauro
AU - De Lisi, Vincenzo
AU - Federico, Massimo
AU - Ferretti, Stefano
AU - Paci, Eugenio
AU - Vettorazzi, Marcello
AU - Zanetti, Roberto
PY - 2002
Y1 - 2002
N2 - Objective: To measure stage-specific geographic and time variability of breast cancer in seven Italian areas before the onset of organized screening programs. Methods: All invasive cancers (8689 cases) arising in women aged 40-79 years during the pre-screening period 1985-1997, were considered. Multiple Poisson regression analysis was performed. Results: About 39% of the cases were classified as "early," 52% as "advanced," and 9% as "unspecified" stage. Age-adjusted incidence rates showed a significant geographic variation for early but not for advanced cancers (range: 58-103 cases/100,000 and 104-125 cases/100,000, respectively). The result was confirmed in the multiple regression analysis after adjustment for year of diagnosis and age. Early breast cancer risk adjusted for age and registry showed a significant increase over time (+ 3.9% per year for all ages, and + 6.2% per year for age category 50-79). In contrast, a decreasing time trend was observed for advanced cancer of 3 cm or over in women aged less than 60. Conclusions: In our study, early breast cancer incidence varied both by geographic area and time before the commencement of screening. The differences in early-stage incidence may well be related to differences in availability of "spontaneous" mammography. Late-stage incidence decreased over time in younger women and for very advanced cases, but not in the older ones, nor for cancers less than 3 cm. Early detection outside organized screening was only partially efficient in reducing advanced breast cancer incidence. The trend of incidence of advanced disease, as previously proposed, is confirmed to be a valid early indicator of effectiveness of screening.
AB - Objective: To measure stage-specific geographic and time variability of breast cancer in seven Italian areas before the onset of organized screening programs. Methods: All invasive cancers (8689 cases) arising in women aged 40-79 years during the pre-screening period 1985-1997, were considered. Multiple Poisson regression analysis was performed. Results: About 39% of the cases were classified as "early," 52% as "advanced," and 9% as "unspecified" stage. Age-adjusted incidence rates showed a significant geographic variation for early but not for advanced cancers (range: 58-103 cases/100,000 and 104-125 cases/100,000, respectively). The result was confirmed in the multiple regression analysis after adjustment for year of diagnosis and age. Early breast cancer risk adjusted for age and registry showed a significant increase over time (+ 3.9% per year for all ages, and + 6.2% per year for age category 50-79). In contrast, a decreasing time trend was observed for advanced cancer of 3 cm or over in women aged less than 60. Conclusions: In our study, early breast cancer incidence varied both by geographic area and time before the commencement of screening. The differences in early-stage incidence may well be related to differences in availability of "spontaneous" mammography. Late-stage incidence decreased over time in younger women and for very advanced cases, but not in the older ones, nor for cancers less than 3 cm. Early detection outside organized screening was only partially efficient in reducing advanced breast cancer incidence. The trend of incidence of advanced disease, as previously proposed, is confirmed to be a valid early indicator of effectiveness of screening.
KW - Breast cancer
KW - Mammographic screening
KW - Stage
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U2 - 10.1023/A:1013950821981
DO - 10.1023/A:1013950821981
M3 - Article
C2 - 11899119
AN - SCOPUS:0036168772
VL - 13
SP - 65
EP - 71
JO - Cancer Causes and Control
JF - Cancer Causes and Control
SN - 0957-5243
IS - 1
ER -