Specificity Of Breast-specific Gamma Imaging Research Articles

Comparison of 99mTc-MIBI scintigraphy, ultrasound, and mammography for the diagnosis of BI-RADS 4 category lesions

BackgroundWe sought to determine the diagnostic efficacy of Breast-specific gamma imaging (BSGI) in Chinese women with BI-RADS 4 category lesions and to compare this efficacy to that of ultrasound/mammography.MethodsWe retrospectively analyzed data from 177 women that had undergone BSGI of BI-RADS 4 category lesions originally detected via ultrasound and/or mammography.ResultsOf these 177 cases, 117 (66.1%) were malignant lesions and 60 (33.9%) were benign. The sensitivity, specificity, positive predictive values, and negative predictive values of BSGI were 94.9% (111/117), 78.3% (47/60), 89.5% (111/124), and 88.7% (47/53), respectively. The specificity and positive predictive values for mammography were 48.3% (29/60) and 77.5% (107/138), while for ultrasound they were 53.3% (32/60) and 79.6% (109/137), respectively. The sensitivity and specificity of BSGI for the detection of lesions ≤1 cm in size were 90.9% (10/11) and 88.0% (22/25), respectively, while for breast lesions >1 cm in size these values were 94.3% (100/106) and 71.4% (25/35), respectively. In addition, BSGI sensitivity and specificity values for dense breast tissue were 94.0% (79/84) and 78.0% (39/50), respectively, whereas for non-dense breast tissue these vales were 97.0% (32/33) and 80.0% (8/10), respectively. The sensitivity of BSGI for invasive ductal carcinomas (IDC) and ductal carcinomas in situ (DCIS) was 98.9% (95/96) and 75.0% (9/12), respectively. The tumor to normal tissue ratio of BSGI for malignant lesions was significantly higher than for benign lesions (2.18 ± 1.17 vs 1.66 ± 0.40, t = 7.56, P<0.05).ConclusionsThese results indicate that BSGI is highly sensitive for the detection of such lesions, achieving good positive/negative predictive values. This suggests that for IDC in particular, BSGI is superior to ultrasound and mammography for the diagnosis of BI-RADS 4 category lesions, although this was less apparent for the diagnosis of DCIS lesions. BSGI exhibited excellent performance in dense breast tissue and for the detection of lesions ≤1 cm in size.

Validity of breast-specific gamma imaging for Breast Imaging Reporting and Data System 4 lesions on mammography and/or ultrasound.

PurposeThe purpose of this study was to assess the breast-specific gamma imaging (BSGI) in Breast Imaging Reporting and Data System (BI-RADS) 4 lesions on mammography and/or ultrasound.MethodsWe performed a retrospective review of 162 patients who underwent BSGI in BI-RADS 4 lesions on mammography and/or ultrasound.ResultsOf the 162 breast lesions, 66 were malignant tumors and 96 were benign tumors. Sensitivity and specificity of BSGI were 90.9% and 78.1%, and positive predictive value and negative predictive value were 74.1% and 92.6%. The sensitivity or specificity of mammography and ultrasound were 74.2% and 56.3% and 87.9% and 19.8%, respectively. The sensitivity and specificity of BSGI for breast lesions ≤1 cm were 88.0% and 86.8%, while the values of beast lesions >1 cm were 92.7% and 61.5%. The sensitivity or specificity of BSGI and mammography for patients with dense breasts were 92.0% and 81.3% and 72.0% and 50.0%, respectively. 26 patients showed neither a nodule nor microcalcification on ultrasound, but showed suspicious calcification on mammography. The sensitivity and specificity of BSGI with microcalcification only lesion were 75.0% and 94.4%.ConclusionThis study demonstrated that BSGI had shown high sensitivity and specificity, as well as positive and negative predictive values in BI-RADS 4 lesions on ultrasound and/or mammography. BSGI showed excellent results in dense breasts, in lesions that are less than 1 cm in size and lesions with suspicious microcalcification only.

Diagnostic value of breast specific gamma imaging with combined visual and semi-quantitative method in patients with breast carcinoma

Objective To evaluate the value of breast specific gamma imaging (BSGI) in detecting primary breast cancer by combined visual and semi-quantitative method. Methods A total of 106 patients suspected of having breast cancer underwent BSGI. The diagnosis was confirmed by histological examination. Interpretation for BSGI was based on the visual (grades 1-5) and semi-quantitative assessment. For patients assessed as grade=3 or above, the ROI was drawn on craniocaudal and mediolateral oblique images respectively, and the count ratio of lesion to adjacent normal breast tissue (L/N) was calculated. The higher value of L/N was selected as index quantitative parameter. The optimal visual grade and L/N cut-off value were obtained through ROC analysis. The sensitivity and specificity of BSGI based on visual-only and combined visual and semi-quantitative assessment were evaluated respectively. Two-sample t test was used to analyze the data. Results Postoperative pathological results confirmed 34/106 cases (49 benign lesions) as benign and 72/106 as breast cancer (73 malignant lesions and 4 benign lesions). The optimal visual grade was 3.5, with ROC AUC of 0.901 (95% CI: 0.838-0.965), sensitivity of 94.4% (68/72) and specificity of 73.5% (25/34). The cut-off value of L/N was 1.92, with ROC AUC of 0.870 (95% CI: 0.756-0.984). The L/N value of patients with breast cancer was significantly higher than that of benign cases (3.29±1.30 vs 2.02±0.65; t=5.63, P<0.05). The sensitivity and specificity of combined visual and semi-quantitative method were 91.7%(66/72) and 88.2%(30/34) for diagnosing primary breast cancer. Conclusion Combined visual and semi-quantitative method on BSGI might improve the specificity for the diagnosis of breast carcinoma. Key words: Breast neoplasms; Radionuclide imaging; Mammography

Complementary Role of Semiquantitative Analysis of Breast-Specific Gamma Imaging in the Diagnosis of Breast Cancer

We investigated whether the interpretation of breast-specific gamma imaging (BSGI) with visual and semiquantitative analyses can improve the diagnosis of breast cancer. The records of 114 women (mean age±SD, 49.6±9.8 years) who underwent BSGI, mammography, and ultrasound to evaluate a breast lesion or lesions were reviewed retrospectively. The breast lesions identified with BSGI were compared with those identified with mammography and ultrasound. BSGI was first interpreted visually, and then a semiquantitative analysis was performed. For the semiquantitative analysis, the uptake ratio for each breast lesion was calculated by dividing the tumor uptake by the contralateral normal breast uptake. Four of the 114 patients had two breast lesions, so a total of 118 breast lesions (42 malignant lesions and 76 benign lesions) were evaluated. A BSGI uptake ratio cutoff of 1.5, with values less than 1.5 indicating negative for cancer, as determined by receiver operating characteristic curve analysis of our data (area under curve, 0.874), was used for semi-quantitative analysis. The sensitivity and specificity of BSGI with visual analysis alone for assessing malignant breast lesions were 76.2% (32/42) and 81.6% (62/76), respectively. For BSGI with visual and semiquantitative analyses, the sensitivity and specificity were 76.2% (32/42) and 92.1% (70/76), respectively. The sensitivity and specificity for mammography were 57.1% (24/42) and 81.6% (62/76), respectively. For ultrasound, the respective values were 97.6% (41/42) and 61.8% (47/76). BSGI with visual and semiquantitative analyses had a significantly higher specificity than BSGI with visual analysis alone, mammography, and ultrasound (all, p<0.01). Semiquantitative analysis of BSGI with visual interpretation may be a useful complementary method for evaluating malignant breast lesions.

Visual and semi-quantitative analyses of dual-phase breast-specific gamma imaging with Tc-99m-sestamibi in detecting primary breast cancer

Breast cancer is the most common malignancy for females worldwide. This study was to evaluate the application of dual-phase breast-specific gamma imaging (BSGI) in detecting primary breast cancer. Seventy-six patients with indeterminate breast lesions that underwent dual-phase BSGI enrolled in this study. All included lesions were confirmed by pathology. BSGI was evaluated based on the visual interpretation and dual-phase semi-quantitative indices of lesion to non-lesion ratio (L/N), which were compared with pathological results. The optimal visual analysis and L/N for double-phase were calculated through receiver operating characteristic curve analysis. Among 76 patients, 92 lesions were finally confirmed by the surgery and pathology, with 54 malignant and 38 benign lesions. Both early and delayed L/N of malignant breast diseases were significantly higher than those of benign (3.18±1.57 vs 1.53±0.59, and 2.91±1.91 vs 1.46±0.54, P<0.05). The optimal visual interpretation is over grade 3, and cut-off L/N was 2.06 and 1.77 for early and delayed imaging, respectively. Compared with visual analysis over grade 3 (77.8 and 81.6%), optimal early L/N (81.5 and 92.1%) or delayed L/N (79.5 and 89.5%) alone, the sensitivity and specificity of visual combined with early-phase L/N in diagnosing primary breast cancer are higher, which were 85.2 and 92.2%, respectively. The combination of visual and semi-quantitative analysis could improve the sensitivity and specificity of BSGI in detecting primary breast cancer. In addition, the potential value of delayed BSGI in diagnosing primary breast cancer should be further investigated in large samples.

A comparative study of breast-specific gamma imaging with the conventional imaging modality in breast cancer patients with dense breasts

The aim of this study was to evaluate the value of breast-specific gamma imaging (BSGI) as compared with mammography (MMG) and ultrasonography (US). This study retrospectively enrolled 121 women with breast cancer (45.0 ± 8.1 years) and dense breasts (breast density >50 %). All patients underwent preoperative BSGI, MMG, and US, and the results were correlated with the biopsy results. In the 121 patients, 153 breast lesions were malignant tumors and 75 lesions were diagnosed as benign tumors. The sensitivity and specificity of BSGI were 92.2 and 89.3 %, while the values of MMG and US were 53.6 and 94.7 and 91.5 and 53.3 %, respectively (p < 0.0001 and p < 0.0004). In breast lesions ≤1 cm, the sensitivity and specificity of BSGI were 80.6 and 91.5 %, which were different from MMG and US, respectively (p < 0.0001 and p < 0.0003). Of 28 patients with 59 multiplicities, BSGI and US found 49 lesions and 51 lesions correctly. However, MMG detected only 26 lesions as malignancies. Given the results of this study, women with dense breasts are not evaluated with MMG at all and went straight to US or MRI in order to minimize radiation exposure. Due to the high false-positive rate of these modalities, BSGI could then be utilized if the US or MRI are positive.

Usefulness of breast-specific gamma imaging as an adjunct modality in breast cancer patients with dense breast: a comparative study with MRI

The aim of this study was to evaluate the adjunctive benefits of breast-specific gamma imaging (BSGI) versus magnetic resonance imaging (MRI) in breast cancer patients with dense breasts. This study included a total of 66 patients (44.1 ± 8.2 years) with dense breasts (breast density >50%) and already biopsy-confirmed breast cancer. All of the patients underwent BSGI and MRI as part of an adjunct modality before the initial therapy. Of 66 patients, the 97 undetermined breast lesions were newly detected and correlated with the biopsy results. Twenty-six of the 97 breast lesions proved to be malignant tumors (invasive ductal cancer, n = 16; ductal carcinoma in situ, n = 6; mixed or other malignancies, n = 4); the remaining 71 lesions were diagnosed as benign tumors. The sensitivity and specificity of BSGI were 88.8% (confidence interval (CI), 69.8-97.6%) and 90.1% (CI, 80.7-95.9%), respectively, while the sensitivity and specificity of MRI were 92.3% (CI, 74.9-99.1%) and 39.4% (CI, 28.0-51.7%), respectively (p < 0.0001). MRI detected 43 false-positive breast lesions, 37 (86.0%) of which were correctly diagnosed as benign lesions using BSGI. In 12 malignant lesions <1 cm, the sensitivities of BSGI and MR imaging were 83.3% (CI, 51.6-97.9%) and 91.7% (CI, 61.5-99.8%), respectively. BSGI showed an equivocal sensitivity and a high specificity compared to MRI in the diagnosis of breast lesions. In addition, BSGI had a good sensitivity in discriminating breast cancers ≤1 cm. The results of this study suggest that BSGI could play a crucial role as an adjunctive imaging modality which can be used to evaluate breast cancer patients with dense breasts.

MRI Versus Breast-Specific Gamma Imaging (BSGI) in Newly Diagnosed Ductal Cell Carcinoma-in-situ: A Prospective Head-to-Head Trial

Mammography remains the standard imaging technique for the diagnosis of ductal carcinoma-in-situ (DCIS). Functional breast imaging, including breast magnetic resonance imaging (MRI), has known limitations in evaluating DCIS. To date, there are limited data on the utility of breast-specific gamma imaging (BSGI) in DCIS. We sought to prospectively compare the sensitivity of BSGI to MRI in newly diagnosed DCIS patients. Patients with newly diagnosed DCIS from June 1, 2009, through May 31, 2010, underwent a protocol with both breast MRI and BSGI. Each imaging study was read by a separate dedicated breast radiologist. Patients were excluded if excisional biopsy was performed for diagnosis, if their MRI was performed at an outside facility, or if final pathology revealed invasive carcinoma. There were 18 patients enrolled onto the study that had both MRI and BSGI for newly diagnosed DCIS. The sensitivity for MRI was 94% and for BSGI was 89% (P>0.5, NS). There was one index tumor not seen on either MRI or BSGI, and one index tumor seen on MRI but not visualized on BSGI. Although BSGI has previously been shown to be as sensitive as MRI for detecting known invasive breast carcinoma, this study shows that BSGI is equally as sensitive as MRI at detecting newly diagnosed DCIS. As a result of the limited number of patients enrolled onto the study, larger prospective studies need to be performed to determine the true sensitivity and specificity of BSGI.

Abstract P5-01-03: MRI vs Breast Specific Gamma Imaging (BSGI) in Newly Diagnosed Breast Cancer: A Prospective Head-to-Head Trial

Abstract Introduction: Functional breast imaging is emerging as an adjunct to mammography and ultrasound in newly diagnosed breast cancer patients. Magnetic resonance Imaging (MRI) is the modality most widely employed. However, it is expensive, uncomfortable for certain patients, and interpretation is variable, depending upon a radiologist's expertise. Breast Specific Gamma Imaging (BSGI) has emerged as an alternative functional imaging study. While MRI evaluates differential enhancement of benign versus malignant lesions, BSGI evaluates the metabolic activity of normal versus abnormal cells by tagging mitochondria with Technecium99. In retrospective analyses, BSGI has been found to have similar sensitivity to MRI, but to date there has not been a prospective trial comparing these modalities in newly diagnosed breast cancer patients. We sought to prospectively compare BSGI to MRI in newly diagnosed breast cancer patients, to determine if this newer functional imaging study is as sensitive to MRI in detecting index lesions. Methods: Patients with newly diagnosed invasive breast cancer from June 1, 2009 through May 31, 2010 were consented for an IRB approved protocol in which they underwent both breast MRI and BSGI. Each imaging study was read by a dedicated breast radiologist, with one radiologist reading all MRI, and another reading all BSGI studies. All subsequent biopsies were performed percutaneously, using image guidance. Patients were excluded if excisional biopsy was performed for diagnosis, or their MRI was performed at an outside facility. Patients with DCIS were also excluded. The sensitivity for each modality was calculated. Results: There were 53 patients enrolled in the study that had both MRI and BSGI for newly diagnosed invasive breast cancer. The sensitivity for MRI was 96% and for BSGI was 91% (Table 1) (P&amp;gt;0.5, ns). There was one index tumor not seen on either MRI or BSGI. It was a 2mm invasive ductal carcinoma diagnosed by calcifications on mammogram. The other index tumor not seen on MRI was visualized on BSGI. Two of the remaining four index tumors not visualized on BSGI were located in the posterior breast. Two studies were false negative. These four lesions were visualized on MRI. Discussion: In this prospective study comparing BSGI to MRI for newly diagnosed invasive breast cancer, BSGI was found to be as sensitive as MRI at detecting index lesions. Of the four false negative BSGI, two tumors were located near the chest wall, a known limitation of this technology. Larger prospective studies need to be performed to determine the true sensitivity and specificity of BSGI. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-01-03.

Breast-specific Gamma Imaging as an Adjunct Imaging Modality for the Diagnosis of Breast Cancer

To retrospectively determine the sensitivity and specificity of breast-specific gamma imaging (BSGI) for the detection of breast cancer by using pathologic results as the reference standard. This study was Institutional Review Board approved and Health Insurance Portability and Accountability Act compliant. Informed consent was obtained for participants who were not imaged as part of their clinical protocol but were participating in other Institutional Review Board-approved studies that used BSGI. A retrospective review of 146 women (aged 32-98 years) undergoing BSGI and breast biopsy was performed. Patients underwent BSGI with intravenous injection of 30 mCi (1110 MBq) of technetium 99 ((99m)Tc)-sestamibi and were imaged in craniocaudal and mediolateral oblique projections. Study images were assigned scores, and scores were classified as positive (focal increased radiotracer uptake) or negative (no uptake or scattered heterogeneous physiologic uptake) and compared with biopsy results. The sensitivity, specificity, and positive and negative predictive values were determined. In 146 patients, 167 lesions underwent biopsy, of which 83 (16 ductal carcinoma in situ [DCIS] and 67 invasive cancers) were malignant. Of 84 nonmalignant lesions, 82 were benign and two showed atypical histologic results (one atypical lobular hyperplasia and one lobular carcinoma in situ). BSGI helped detect cancer in 80 of 83 malignant lesions with a sensitivity of 96.4% (95% confidence interval [CI]: 92%, 99%) and correctly identified 50 of 84 nonmalignant lesions as negative for cancer with a specificity of 59.5% (95% CI: 49%, 70%). The positive predictive value for 80 of 114 malignant lesions with a BSGI examination with findings positive for cancer was 68.8% (95% CI: 60%, 78%) and the negative predictive value for 50 of 53 nonmalignant lesions was 94.3% (95% CI: 88%, 99%). The smallest invasive cancer and DCIS detected were both 1 mm. BSGI helped detect occult cancer not visualized at mammography or ultrasonography in six patients. BSIG has high sensitivity (96.4%) and moderate specificity (59.5%) helping detect breast cancers.

Breast-Specific Gamma Imaging with99mTc-Sestamibi and Magnetic Resonance Imaging in the Diagnosis of Breast Cancer?A Comparative Study

The purpose of this study was to compare the sensitivity and specificity of breast-specific gamma imaging (BSGI) using a high-resolution breast-specific gamma camera and magnetic resonance imaging (MRI) in patients with indeterminate breast findings. Twenty-three women with an indeterminate breast finding that required BSGI and MRI as deemed necessary by the interpreting radiologist or referring physician were included. MRI was performed on a GE 1.5T scanner and BSGI was performed on a Dilon high-resolution breast-specific gamma camera. All imaging findings were correlated with pathologic diagnosis. Thirty-three indeterminate lesions were evaluated in the study. There were a total of nine pathologically confirmed cancers. There was no statistically significant difference in sensitivity of cancer detection between BSGI and MRI. BSGI demonstrated a greater specificity than MRI, 71% and 25%, respectively. BSGI has equal sensitivity and greater specificity than MRI for the detection of breast cancer.