TY - JOUR
T1 - Background parenchymal uptake on molecular breast imaging as a breast cancer risk factor
T2 - A case-control study
AU - Hruska, Carrie B.
AU - Scott, Christopher G.
AU - Conners, Amy Lynn
AU - Whaley, Dana H.
AU - Rhodes, Deborah J.
AU - Carter, Rickey E.
AU - O'Connor, Michael K.
AU - Hunt, Katie N.
AU - Brandt, Kathleen R.
AU - Vachon, Celine M.
N1 - Funding Information:
This work was supported by grants from the National Cancer Institute (R21 CA197752), the National Center for Advancing Translational Sciences (UL1 TR000135), and the Mayo Clinic Cancer Center, Fraternal Order of Eagles Cancer Research Fund. The authors thank Matt Jensen for statistical programming support, Fang Fang Wu for performing quantitative density measurements, and research nurses Wendy Gay, Denise Herman, Mary Dugdale, and Susan Moen for abstracting covariate data. The authors also acknowledge Dr. Stephen W. Phillips for initially questioning the importance of background parenchymal uptake on molecular breast imaging.
Publisher Copyright:
© 2016 Hruska et al.
PY - 2016
Y1 - 2016
N2 - Background: Molecular breast imaging (MBI) is a functional test used for supplemental screening of women with mammographically dense breasts. Additionally, MBI depicts variable levels of background parenchymal uptake (BPU) within nonmalignant, dense fibroglandular tissue. We investigated whether BPU is a risk factor for breast cancer. Methods: We conducted a retrospective case-control study of 3027 eligible women who had undergone MBI between February 2004 and February 2014. Sixty-two incident breast cancer cases were identified. A total of 179 controls were matched on age, menopausal status, and MBI year. Two radiologists blinded to case status independently assessed BPU as one of four categories: photopenic, minimal to mild, moderate, or marked. Conditional logistic regression analysis was performed to estimate the associations (OR) of BPU categories (moderate or marked vs. minimal to mild or photopenic) and breast cancer risk, adjusted for other risk factors. Results: The median age was 60.2 years (range 38-86 years) for cases vs. 60.2 years (range 38-88 years) for controls (p = 0.88). Women with moderate or marked BPU had a 3.4-fold (95 % CI 1.6-7.3) and 4.8-fold (95 % CI 2.1-10.8) increased risk of breast cancer, respectively, compared with women with photopenic or minimal to mild BPU, for two radiologists. The results were similar after adjustment for BI-RADS density (OR 3.3 [95 % CI 1.6-7.2] and OR 4.6 [95 % CI 2.1-10.5]) or postmenopausal hormone use (OR 3.6 [95 % CI 1.7-7.7] and OR 5.0 [95 % CI 2.2-11.4]). The association of BPU with breast cancer remained in analyses limited to postmenopausal women only (OR 3.8 [95 % CI 1.5-9.3] and OR 4.1 [95 % CI 1.6-10.2]) and invasive breast cancer cases only (OR 3.6 [95 % CI 1.5-8.8] and OR 4.4 [95 % CI 1.7-11.1]). Variable BPU was observed among women with similar mammographic density; the distribution of BPU categories differed across density categories (p < 0.0001). Conclusions: This study provides the first evidence for BPU as a risk factor for breast cancer. Among women with dense breasts, who comprise > 40 % of the screening population, BPU may serve as a functional imaging biomarker to identify the subset at greatest risk.
AB - Background: Molecular breast imaging (MBI) is a functional test used for supplemental screening of women with mammographically dense breasts. Additionally, MBI depicts variable levels of background parenchymal uptake (BPU) within nonmalignant, dense fibroglandular tissue. We investigated whether BPU is a risk factor for breast cancer. Methods: We conducted a retrospective case-control study of 3027 eligible women who had undergone MBI between February 2004 and February 2014. Sixty-two incident breast cancer cases were identified. A total of 179 controls were matched on age, menopausal status, and MBI year. Two radiologists blinded to case status independently assessed BPU as one of four categories: photopenic, minimal to mild, moderate, or marked. Conditional logistic regression analysis was performed to estimate the associations (OR) of BPU categories (moderate or marked vs. minimal to mild or photopenic) and breast cancer risk, adjusted for other risk factors. Results: The median age was 60.2 years (range 38-86 years) for cases vs. 60.2 years (range 38-88 years) for controls (p = 0.88). Women with moderate or marked BPU had a 3.4-fold (95 % CI 1.6-7.3) and 4.8-fold (95 % CI 2.1-10.8) increased risk of breast cancer, respectively, compared with women with photopenic or minimal to mild BPU, for two radiologists. The results were similar after adjustment for BI-RADS density (OR 3.3 [95 % CI 1.6-7.2] and OR 4.6 [95 % CI 2.1-10.5]) or postmenopausal hormone use (OR 3.6 [95 % CI 1.7-7.7] and OR 5.0 [95 % CI 2.2-11.4]). The association of BPU with breast cancer remained in analyses limited to postmenopausal women only (OR 3.8 [95 % CI 1.5-9.3] and OR 4.1 [95 % CI 1.6-10.2]) and invasive breast cancer cases only (OR 3.6 [95 % CI 1.5-8.8] and OR 4.4 [95 % CI 1.7-11.1]). Variable BPU was observed among women with similar mammographic density; the distribution of BPU categories differed across density categories (p < 0.0001). Conclusions: This study provides the first evidence for BPU as a risk factor for breast cancer. Among women with dense breasts, who comprise > 40 % of the screening population, BPU may serve as a functional imaging biomarker to identify the subset at greatest risk.
KW - Breast cancer risk
KW - Breast density
KW - Mammography
KW - Molecular breast imaging
KW - Tc-99m sestamibi
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U2 - 10.1186/S13058-016-0704-6
DO - 10.1186/S13058-016-0704-6
M3 - Article
C2 - 27113363
AN - SCOPUS:85008657204
SN - 1465-5411
VL - 18
JO - Breast Cancer Research
JF - Breast Cancer Research
IS - 1
M1 - 42
ER -