CDR - Cancer Detection Rate
What is the Cancer Detection Rate?
The Cancer Detection Rate (CDR) provides the number of identified cancers per 1,000 imaging examinations.
For what is the Cancer Detection Rate calculated?
The Cancer Detection Rate is calculated for both screening and diagnostic mammograms. Funaro et al. recommend that for screening mammograms, the CDR should be calculated separately for prevalent cancers in the first round of screening imaging as well as for incident cancers found in the following round of screening (Funaro et al., 2021).
What is the performance benchmark for a facility’s Cancer Detection Rate?
The BI-RAD Atlas performance benchmarks for a facility’s Cancer Detection Rate (per 1,000 mammograms completed) are as follows (Sickles et al., 2013):
- Screening mammograms: ≥ 2.5
- Diagnostic mammograms with an abnormal finding: ≥ 20
- Diagnostic mammograms with a palpable lump: ≥ 40
Why is the Cancer Detection Rate useful?
Within a Mammography Medical Audit, calculating the Cancer Detection Rate is useful in determining if a facility is meeting one of the main goals of breast cancer screening: detecting a high percentage of breast cancer in asymptomatic women undergoing screening mammograms (Funaro et al., 2021).
How is the Cancer Detection Rate calculated?
The Breast Cancer Surveillance Consortium lists the formula for determining the Cancer Detection Rate as: (CDR) = 1000 * TP / (TP + FP + FN + TN)
- CDR= Cancer Detection Rate
- TP= True Positives
- FP= False Positives
- FN= False Negatives
- TN= True Negatives
Sources:
FDA Breast Cancer Surveillance Consortium. (2021). BCSC Standard Definitions, Version 3. https://www.bcsc-research.org/application/files/6916/1429/6964/BCSC_Data_Definitions_v3__2020.09.23.pdf
Funaro, Kimberly, et al. (2021). Understanding the Mammography Audit. Radiologic Clinics of North America vol. 59,1 (2021): 41–55. doi:10.1016/j.rcl.2020.09.009
Sickles, EA, D'Orsi CJ, Bassett LW, et al. (2013). ACR Bl-RADS Mammography. In: ACR BI-RADS Atlas, Breast Imaging Reporting and Data System. American College of Radiology. https://www.acr.org/Clinical-Resources/Reporting-and-Data-Systems/Bi-Rads#Mammography
