A study presented at the San Antonio Breast Cancer Symposium evaluated the usefulness of a patient-administered breast cancer risk assessment (CRA) in detecting cancer.
Between January 2017 and June 2018, 32,024 women undergoing mammograms were invited to take the CRA survey. Women were excluded if they declined the CRA (n=8,438) or were symptomatic (n=7), leaving 23,579 eligible women. Among the eligible patients, 16,548 had one screening during the study, and 7,031 had two screenings; final analysis included 30,610 total screening mammograms in women who completed the CRA.
The BRCAPRO and Tyrer-Cuzick v7 (TC7) models were used to determine the lifetime breast cancer risk, and the BRCAMUTATION model was used to determine BRCA mutation risk. High-risk (HR) patients had a BRCAPRO or TC7 lifetime risk higher than 20% or a BRCAMUTATION risk higher than 5%. All other patients were classified as low-risk (LR). Four pathology classifications were used: invasive cancer, in situ cancer (excluding lobular carcinoma in situ without pleomorphic features), benign excision (frequently surgically excised, including atypia and complex sclerosing lesion), and benign. The researchers calculated and compared the call back rate (percent of BIRADS 0 per screening mammogram, CBR), cancer detection rate (number of invasive plus in situ cancers per 1,000 screening mammograms, CDR), and percent (as a fraction of screening mammograms) of each of the four pathology groups between the HR and LR screens.
The majority of screens were LR (n=26,460; 86.4%), while 13.6% (n=4,150) were HR. CBR was higher for HR than LR (11.1% vs. 8.1%; P<0.0001). Subsequent diagnostic imaging revealed that 2.4% (n=101) of HR and 1.4% (n=442) of LR patients received a BIRADS 4 or 5 (P<0.05); four HR and 18 LR patients chose not to undergo biopsy. CDR was 7.7 in the HR group and 4.6 in the LR group (P<0.05). Pathologies in the HR group were 0.63% invasive cancer, 0.14% in situ cancer, 0.22% benign excision, and 1.3% benign. In the LR group, pathologies were 0.34% invasive cancer, 0.12% in situ cancer, 0.26% benign excision, and -0.87% benign.
The authors concluded, “These results indicate that this self-administered breast cancer risk stratification is clinically relevant.”