Response: Re: Breast Cancer Incidence, 1980–2006: Combined Roles of Menopausal Hormone Therapy, Screening Mammography, and Estrogen Receptor Status

JNCI Journal of the National Cancer Institute, Dec 2007

Andrew G. Glass, James V. Lacey JR, Joseph D. Carreon, Robert N. Hoover

A PDF file should load here. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser.

Alternatively, you can download the file locally and open with any standalone PDF reader:

https://jnci.oxfordjournals.org/content/99/23/1819.1.full.pdf

Response: Re: Breast Cancer Incidence, 1980–2006: Combined Roles of Menopausal Hormone Therapy, Screening Mammography, and Estrogen Receptor Status

0 The Author 2007. Published by Oxford University Press. All rights reserved. For Permissions , please 1 Oncology Research, Center for Health Research, Kaiser Permanente Northwest , 3800 N Interstate Ave, Portland, OR 97227 ( 2 Affiliations of authors: Oncology Research, Center for Health Research, Kaiser Permanente Northwest, Portland, OR (AGG); Division of Cancer Epidemiology and Genetics, National Cancer Institute , Rockville, MD (JVL, JDC, RNH) Re: Breast Cancer Incidence, 1980-2006: Combined Roles of Menopausal Hormone Therapy, Screening Mammography, and Estrogen Receptor Status - In contrast to the results reported by Glass et al. (1), who showed a marked decrease in breast cancer incidence in 2003 in women members of the Kaiser Permanente Northwest prepaid health plan, we observed All screening mammographies First screen mammographies Incidence rate 50 years of age As above, cases detected at first screen excluded Incidence rate <50 years of age a drop in breast cancer incidence during 19992001 but not during 20012003 in the population of Turin, Italy. This city has been covered since 1985 by a populationbased cancer registry that contributes to data published in the International Agency for Research on Cancer publication Cancer Incidence in Five Continents (2) and since 1992 by a centrally organized mammography screening program with personal invitations every 2 years to women aged 5069 (3). Both activities are run under the responsibility of the Centro per la Prevenzione Oncologica, which maintains the respective computerized databases of individual records. We analyzed invasive breast cancer incidence time trends in Turin from 1985 to 2003 (total number of cases = 13 625). We used record linkage to investigate how the trend is affected by any changes in mammography screening. Our institution, as part of its duties in screening evaluation, is entitled to perform such a linkage under a waiver of written informed consent. Each individual breast cancer case was then categorized as screen detected at first screen, screen detected at subsequent screen, or not screen detected. We tabulated separately the incidence trends in the group of cancers obtained after the exclusion of all cases detected at first screen, the so-called unbiased set (4). Cases detected at the first test are likely to be composed predominantly of prevalent, slow-growing cases that, if mammography had not taken place, would have appeared clinically several years after screen detection. In all ages combined, age-standardized incidence decreased at a statistically significant annual estimated percentage change of 2.6%, from 127.4 cases per 100 000 in 1999 to 115.1 in 2003 (joinpoint regression). However, the decrease was steeper in the period 19992001 (3.1%, from 127.4 to 119.5). This trend was restricted to women in the older age classes (Fig. 1). When all cases detected at the first screen were excluded, both the increasing time trend and the subsequent decrease almost completely flattened. Furthermore, the trend in the number of first screens strictly paralleled population cancer incidence, whereas the total number of screening mammographies did not (Fig. 1). Use of hormone replacement therapy by postmenopausal women is lower in Northern Italy than in United States, not exceeding 15% in the mid-90s (5). Although a reduction in hormone replacement therapy consumption has been indeed reported in Italy in 2002 and 2003 [estrogen prescriptions decreased nationwide by 15.3% and 18.0%, respectively, in those years (6)], it is therefore not surprising that this reduction has not translated in a marked decline in breast cancer incidence. On the other hand, we believe that, in our data, the trend in invasive breast cancer incidence is largely explained by the slow increase during 19921999 of screendetected cases at first screen and by their decrease thereafter. Such an interpretation may be relevant to other geographical areas in which organized or spontaneous screening reaches a plateau after an increase in the preceding years. Indeed, this possibility has been suggested, albeit with no support by record linkage, in relation to the American data (7). To verify this hypothesis, it would be of interest if Glass et al. could provide any information on the volume of screening mammographies for first and subsequent tests separately. ANTONIO PONTI STEFANO ROSSO ROBERTO ZANETTI FULVIO RICCERI MARIANO TOMATIS NEREO SEGNAN Notes Affiliations of authors: Unit of Epidemiology (AP, MT, NS) and Piedmont Cancer Registry (SR, RZ, FR), Centro per la Prevenzione Oncologica, Turin, Italy. Correspondence to: Antonio Ponti, MD, MPH, Centro per la Prevenzione Oncologica, Unit of Epidemiology, via S. Francesco da Paola, 31, Turin, TO 10123 Italy (e-mail: ). DOI: 10.1093/jnci/djm225 The Author 2007. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: . Response We read with interest the letter from Ponti et al. Rising breast cancer incidence rates in Turin between 1992 and 1999 seem, like our 1980s data (1), to reflect the influence of initial screening mammography. Individual-level data from populations with substantial exposure to menopausal hormone therapy and established screening programs, such as Kaiser Permanente Northwest and others (2), may be necessary to fully understand the combined effects of these factors on breast cancer incidence. ANDREW G. GLASS JAMES V. LACEY JR JOSEPH D. CARREON ROBERT N. HOOVER


This is a preview of a remote PDF: https://jnci.oxfordjournals.org/content/99/23/1819.1.full.pdf

Andrew G. Glass, James V. Lacey JR, Joseph D. Carreon, Robert N. Hoover. Response: Re: Breast Cancer Incidence, 1980–2006: Combined Roles of Menopausal Hormone Therapy, Screening Mammography, and Estrogen Receptor Status, JNCI Journal of the National Cancer Institute, 2007, 1819-1819, DOI: 10.1093/jnci/djm226