Downgrading and Upgrading Gray-Scale Ultrasound BI-RADS Categories of Benign and Malignant Masses With Optoacoustics: A Pilot Study.

OBJECTIVE: False-positive findings remain challenging in breast imaging. This study investigates the incremental value of optoacoustic imaging in improving BI-RADS categorization of breast masses at ultrasound. SUBJECTS AND METHODS: The study device is an optoacoustic breast imaging device with a handheld duplex laser and internal gray-scale ultrasound probe, fusing functional and morphologic information (optoacoustic ultrasound). In this prospective multisite study, breast masses assessed as BI-RADS category 3, 4A, 4B, 4C, or 5 by site radiologists underwent both gray-scale ultrasound and optoacoustic imaging with the study device. Independent reader radiologists assessed internal gray-scale ultrasound and optoacoustic ultrasound features for each mass and assigned a BI-RADS category. The percentage of mass reads for which optoacoustic ultrasound resulted in a downgrade or upgrade of BI-RADS category relative to internal gray-scale ultrasound was determined. RESULTS: Of 94 total masses, 39 were biopsy-proven malignant, 44 were biopsy-proven benign, and 11 BI-RADS category 3 masses were stable at 12-month follow-up. The sensitivity of both optoacoustic ultrasound and internal gray-scale ultrasound was 97.1%. The specificity was 44.3% for optoacoustic ultrasound and 36.4% for internal gray-scale ultrasound. Using optoacoustic ultrasound, 41.7% of benign masses or BI-RADS category 3 masses that were stable at 12-month follow-up were downgraded to BI-RADS category 2 by independent readers; 36.6% of masses assigned BI-RADS category 4A were downgraded to BI-RADS category 3 or 2, and 10.1% assigned BI-RADS category 4B were downgraded to BI-RADS category 3 or 2. Using optoacoustic ultrasound, independent readers upgraded 75.0% of the malignant masses classified as category 4A, 4B, 4C, or 5, and 49.4% of the malignant masses were classified as category 4B, 4C, or 5. CONCLUSION: Optoacoustic ultrasound resulted in BI-RADS category downgrading of benign masses and upgrading of malignant masses compared with gray-scale ultrasound.

A Pivotal Study of Optoacoustic Imaging to Diagnose Benign and Malignant Breast Masses: A New Evaluation Tool for Radiologists.

Purpose To compare the diagnostic utility of an investigational optoacoustic imaging device that fuses laser optical imaging (OA) with grayscale ultrasonography (US) to grayscale US alone in differentiating benign and malignant breast masses. Materials and Methods This prospective, 16-site study of 2105 women (study period: 12/21/2012 to 9/9/2015) compared Breast Imaging Reporting and Data System (BI-RADS) categories assigned by seven blinded independent readers to benign and malignant breast masses using OA/US versus US alone. BI-RADS 3, 4, or 5 masses assessed at diagnostic US with biopsy-proven histologic findings and BI-RADS 3 masses stable at 12 months were eligible. Independent readers reviewed US images obtained with the OA/US device, assigned a probability of malignancy (POM) and BI-RADS category, and locked results. The same independent readers then reviewed OA/US images, scored OA features, and assigned OA/US POM and a BI-RADS category. Specificity and sensitivity were calculated for US and OA/US. Benign and malignant mass upgrade and downgrade rates, positive and negative predictive values, and positive and negative likelihood ratios were compared. Results Of 2105 consented subjects with 2191 masses, 100 subjects (103 masses) were analyzed separately as a training population and excluded. An additional 202 subjects (210 masses) were excluded due to technical failures or incomplete imaging, 72 subjects (78 masses) due to protocol deviations, and 41 subjects (43 masses) due to high-risk histologic results. Of 1690 subjects with 1757 masses (1079 [61.4%] benign and 678 [38.6%] malignant masses), OA/US downgraded 40.8% (3078/7535) of benign mass reads, with a specificity of 43.0% (3242/7538, 99% confidence interval [CI]: 40.4%, 45.7%) for OA/US versus 28.1% (2120/7543, 99% CI: 25.8%, 30.5%) for the internal US of the OA/US device. OA/US exceeded US in specificity by 14.9% (P < .0001; 99% CI: 12.9, 16.9%). Sensitivity for biopsied malignant masses was 96.0% (4553/4745, 99% CI: 94.5%, 97.0%) for OA/US and 98.6% (4680/4746, 99% CI: 97.8%, 99.1%) for US (P < .0001). The negative likelihood ratio of 0.094 for OA/US indicates a negative examination can reduce a maximum US-assigned pretest probability of 17.8% (low BI-RADS 4B) to a posttest probability of 2% (BI-RADS 3). Conclusion OA/US increases the specificity of breast mass assessment compared with the device internal grayscale US alone. Online supplemental material is available for this article. © RSNA, 2017.

Results of a multicenter patient registry to determine the clinical impact of breast-specific gamma imaging, a molecular breast imaging technique.

OBJECTIVE: Molecular breast imaging techniques, such as breast-specific gamma imaging, are increasingly being used as adjunctive diagnostic technologies to mammography and ultrasound. This multicenter clinical patient registry was designed to quantify the impact of this modality on the management of the breast patient population in clinical practice and to identify the subgroups of patients benefiting from its use. MATERIALS AND METHODS: There were 1042 patients included in this analysis, and breast-specific gamma imaging typically was recommended when the patient had at least two of the following indications: equivocal or negative mammogram or sonogram and an unresolved clinical concern; personal history of breast cancer or current cancer diagnosis; palpable masses negative on mammographic and sonographic examination; radiodense breast tissue; or high risk for breast cancer. Pathologic analysis or follow-up imaging, if biopsy was not conducted, was used as the reference standard, and lesions were classified as positive (i.e., malignant or high risk) in 250 cases and as negative (i.e., benign) in 792 cases. RESULTS: Breast-specific gamma imaging was positive in 408 patients (227 malignant or high-risk lesions requiring additional intervention), negative in 634 patients (23 with malignant or high-risk lesions), and indeterminate in 69 patients (all benign lesions). Breast-specific gamma imaging had an overall sensitivity of 91% and specificity of 77%. CONCLUSION: Breast-specific gamma imaging significantly contributed to the detection of malignant or high-risk lesions in patients with negative or indeterminate mammographic findings, and it provided improved management when compared with ultrasound.

Invasive lobular carcinoma: detection with mammography, sonography, MRI, and breast-specific gamma imaging.

OBJECTIVE: The objective of our study was to compare the sensitivity of mammography, sonography, MRI, and breast-specific gamma imaging (BSGI) in the detection of invasive lobular carcinoma. MATERIALS AND METHODS: This is a retrospective multicenter study of women with biopsy-proven invasive lobular carcinoma. All patients had undergone mammography and BSGI, and the imaging findings were classified as positive or negative for invasive lobular carcinoma by experienced breast imagers. The results of MRI and sonography, if either was performed, were included. Final surgical pathology results were used as the reference standard and the lesion sensitivities of BSGI, mammography, sonography, and MRI were then statistically compared using CIs. RESULTS: Twenty-six women ranging in age from 46 to 82 years (mean age, 62.8 years) with a total of 28 biopsy-proven invasive lobular carcinomas were included in the study group. Mammograms were negative in six of 28 (21%), yielding a sensitivity of 79%. In the 25 patients who underwent sonography, 17 had focal hypoechoic areas, yielding a sensitivity of 68%. In the 12 patients who underwent MRI, the sensitivity was 83%. BSGI had a sensitivity of 93%. There was no statistically significant difference in the sensitivity of BSGI, MRI, sonography, or mammography, although there was a nonsignificant trend toward improved detection with BSGI. CONCLUSION: BSGI has the highest sensitivity for the detection of invasive lobular carcinoma with a sensitivity of 93%, whereas mammography, sonography, and MRI showed sensitivities of 79%, 68%, and 83%, respectively. BSGI is an effective technique that should be used to evaluate patients with suspected cancer and has a promising role in the diagnosis of invasive lobular carcinoma.