Digital Mammography Screening: Does Age Influence the Detection Rates of Low-, Intermediate-, and High-Grade Ductal Carcinoma in Situ?
OBJECTIVE
To investigate the association between age at screening and detection rates for ductal carcinoma in situ (DCIS) separately for different nuclear grades after introduction of a population-based digital mammography screening program.


METHODS
The retrospective study was approved by the ethics board and did not require informed consent. In 733 905 women aged 50-69 years who participated in a screening program for the first time in 2005-2008 (baseline examinations were performed with digital mammography), DCIS detection rates were determined for 5-year age groups (detection rates per 1000 women screened) to distinguish high-, intermediate-, and low-grade DCIS. Multivariable logistic regression was used to compare detection rates between age groups by adjusting for screening units (P < .05).


RESULTS
There were 989 graded DCIS diagnoses among 733 905 women (detection rate, 1.35‰): 419 diagnoses of high-grade DCIS (detection rate, 0.57‰), 388 diagnoses of intermediate-grade DCIS (detection rate, 0.53‰), and 182 diagnoses of low-grade DCIS (detection rate, 0.25‰). Detection rate for types of DCIS combined increased significantly across age groups (50-54 years, detection rate of 1.15‰ [254 of 220 985 women]; 55-59 years, detection rate of 1.23‰ [218 of 177 782 women]; 60-64 years, detection rate of 1.34‰ [201 of 150 415 women]; and 65-69 years, detection rate of 1.71‰ [316 of 184 723 women]; P < .001). Of note, the detection rate for high-grade DCIS showed a significant increase with age (odds ratio, 1.18 per 5-year age group; P < .0001). The increase was lower for intermediate-grade DCIS (odds ratio, 1.11; P = .016) and not significant for low-grade DCIS (P = .10).


CONCLUSIONS
Total DCIS detection rates increase with age, mostly because of an increase in high- and intermediate-grade DCIS, which are precursor lesions that carry a higher risk for transition to more aggressive invasive breast cancer than low-grade DCIS.
From the Department of Clinical Radiology and Reference Center for Mammography (S.W., S.B., W.H.) and Institute of Epidemiology and Social Medicine (H.W.H.), University of Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Muenster, Germany; and Epidemiological Cancer Registry of North Rhine-Westphalia, Muenster, Germany (H.W.H., J.H., O.H.).
Stefanie
S
Weigel
From the Department of Clinical Radiology and Reference Center for Mammography (S.W., S.B., W.H.) and Institute of Epidemiology and Social Medicine (H.W.H.), University of Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Muenster, Germany; and Epidemiological Cancer Registry of North Rhine-Westphalia, Muenster, Germany (H.W.H., J.H., O.H.).
Hans W
HW
Hense
From the Department of Clinical Radiology and Reference Center for Mammography (S.W., S.B., W.H.) and Institute of Epidemiology and Social Medicine (H.W.H.), University of Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Muenster, Germany; and Epidemiological Cancer Registry of North Rhine-Westphalia, Muenster, Germany (H.W.H., J.H., O.H.).
Jan
J
Heidrich
From the Department of Clinical Radiology and Reference Center for Mammography (S.W., S.B., W.H.) and Institute of Epidemiology and Social Medicine (H.W.H.), University of Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Muenster, Germany; and Epidemiological Cancer Registry of North Rhine-Westphalia, Muenster, Germany (H.W.H., J.H., O.H.).
Shoma
S
Berkemeyer
From the Department of Clinical Radiology and Reference Center for Mammography (S.W., S.B., W.H.) and Institute of Epidemiology and Social Medicine (H.W.H.), University of Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Muenster, Germany; and Epidemiological Cancer Registry of North Rhine-Westphalia, Muenster, Germany (H.W.H., J.H., O.H.).
Walter
W
Heindel
From the Department of Clinical Radiology and Reference Center for Mammography (S.W., S.B., W.H.) and Institute of Epidemiology and Social Medicine (H.W.H.), University of Muenster, Albert-Schweitzer-Campus 1, Gebäude A1, 48149 Muenster, Germany; and Epidemiological Cancer Registry of North Rhine-Westphalia, Muenster, Germany (H.W.H., J.H., O.H.).
Oliver
O
Heidinger
D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D002278:Carcinoma in Situ / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008327:Mammography / Q000379:methods*; D008403:Mass Screening; D008875:Middle Aged; D060787:Neoplasm Grading; D011379:Prognosis; D012042:Registries; D012189:Retrospective Studies