Variation in detection of ductal carcinoma in situ during screening mammography: A survey within the International Cancer Screening Network

Authors	LYNGE Elsebeth PONTI Antonio JAMES Ted MÁJEK Ondřej EULER-CHELPIN My von ANTTILA Ahti FITZPATRICK Patricia FRIGERIO Alfonso KAWAI Masaaki SCHARPANTGEN Astrid BROEDERS Mireille HOFVIND Solveig VIDAL Carmen EDERRA Maria SALAS Dolores BULLIARD Jean-Luc TOMATIS Mariano KERLIKOWSKE Karla TAPLIN Stephen
Year of publication	2014
Type	Article in Periodical
Magazine / Source	European Journal of Cancer
MU Faculty or unit	Faculty of Medicine
Citation
Doi	http://dx.doi.org/10.1016/j.ejca.2013.08.013
Field	Oncology and hematology
Keywords	Breast cancer; Ductal carcinoma in situ (DCIS); Screening mammography; Cancer registration
Description	Background: There is concern about detection of ductal carcinoma in situ (DCIS) in screening mammography. DCIS accounts for a substantial proportion of screen-detected lesions but its effect on breast cancer mortality is debated. The International Cancer Screening Network conducted a comparative analysis to determine variation in DCIS detection. Patients and Methods: Data were collected during 2004-2008 on number of screening examinations, detected breast cancers, DCIS cases and Globocan 2008 breast cancer incidence rates derived from national or regional cancer registers. We calculated screen-detection rates for breast cancers and DCIS. Results: Data were obtained from 15 screening settings in 12 countries; 7,176,050 screening examinations; 29,605 breast cancers and 5324 DCIS cases. The ratio between highest and lowest breast cancer incidence was 2.88 (95% confidence interval (CI) 2.76-3.00); 2.97 (95% CI 2.51-3.51) for detection of breast cancer; and 3.49 (95% CI 2.70-4.51) for detection of DCIS. Conclusions: Considerable international variation was found in DCIS detection. This variation could not be fully explained by variation in incidence nor in breast cancer detection rates. It suggests the potential for wide discrepancies in management of DCIS resulting in overtreatment of indolent DCIS or undertreatment of potentially curable disease. Comprehensive cancer registration is needed to monitor DCIS detection. Efforts to understand discrepancies and standardise management may improve care.