Tc-99m Sestamibi Scintimammography Research Articles

Does 99mTc-Sestamibi Uptake Discriminate Breast Tumors?

The aim of this work was to investigate 99mTc-sestamibi uptake and histopathological characteristics of breast tumors. Static 99mTc-sestamibi scintimammography (SMM) has been performed in 101 breast tumors (98 patients). SMM were scored from 0 to 4 according to intensity of 99mTc-sestamibi uptake and classified in two groups: SMM with absence or low tumor uptake (0, 1, 2) and SMM with high tumor uptake (3, 4). Tumor histopathological characteristics have been determined on core or excisional biopsy. The 99mTc-sestamibi uptake (low vs. high) correlated to classical prognostic factors: positively with Scarff-Bloom and Richardson (SBR) grade (p < 0.0005), axillary involvement (p < 0.0005), and tumor size (p < 0.0005) and negatively with estrogen receptors (p < 0.001). Fixation of 99mTc-sestamibi in invasive lobular carcinoma was lower than in invasive ductal carcinoma (p < 0.01) despite a similar mean tumor size (28 ± 14 mm vs. 24 ± 14 mm). Relations between 99mTc-sestamibi uptake and tumor size, histologic type, and axillary involvement were independent variables also significant in multivariate analysis (p < 0.0005, p < 0.005, p < 0.05, respectively). Moreover, the five-year survival rate was higher when 99mTc-sestamibi breast tumor uptake was low (p < 0.005). This difference is also significant using the Cox model (p < 0.05). Uptake of 99mTc-sestamibi (low vs. high) discriminates breast tumors with different histopathological characteristics and prognosis.

The value of scintimammography in reduction mammaplasties: a preliminary study.

Reduction mammaplasty results in architectural distortion, fat necrosis, and heavy scarring of the breast. In such conditions, mammography (MG) might not be reliable and an alternative unfailing imaging technique is demanded to prevent unnecessary apprehension and biopsy. With this study, the value of Tc-99m sestamibi (MIBI) scintimammography (SCM) as an adjunct test after reduction mammaplasty was explored. MIBI scintigraphy is not affected by scar tissue or breast density and is able to differentiate benign and malignant lesions. The study was conducted on 12 women undergoing a reduction mammaplasty operation (McKissock technique). The average age was 38 and the average weight of breast tissue removed from each breast was 320 g. All patients, except one who was 21 years old, underwent MG and SCM preoperatively, and these tests were repeated at the sixth postoperative month. Preoperative MG and SCM revealed no pathology except a finding in one patient consistent with fibroadenoma. Postoperatively, the most common findings in MG were parenchymal redistribution, elevation of the nipple, and retroareolar fibrotic bands. Calcifications and oil cysts were not seen. Other findings were areola and skin thickening. Interestingly, these findings were not evident on the SCM, in fact it was not possible to state whether or not the breast had been operated on. In conclusion, SCM may not be used as screening test, but it should be considered when the postoperative MG is not informative or is complicated by scaring. In this condition, SCM may be used as a complementary method to MG and may help to prevent unnecessary breast biopsies.

In vivo detection of resistance to anthracycline based neoadjuvant chemotherapy in locally advanced and inflammatory breast cancer with technetium-99m sestamibi scintimammography

Neoadjuvant chemotherapy (NACT) is the treatment of choice in patients (pts) with locally advanced (LABC) and inflammatory breast cancer (IBC). To evaluate the role of Tc-99m sestamibi imaging in the prediction of response to NACT and in the in vivo functional detection of intrinsic or acquired chemoresistance, 24 female pts with LABC (n=21) or IBC (n=3) were prospectively studied. Tc-99m scintimammography was performed 1-3 days before treatment (first) and 2-5 days after the completion (second) of NACT (epirubicin and cyclophosphamide for LABC and doxorubicin and vinorelbine for IBC). Three planar images (2 lateral prone and one anterior supine, 10 min/each) were obtained 10 min postinjection and a lateral prone image (10 min) of the affected breast (B) was obtained at 4 h. To calculate the tumor to normal B ratio (TBR), 2 identical irregular regions of interest (ROIs) were drawn around the tumor (T) and in adjacent ipsilateral normal B on both early (E) and delayed (D) prone lateral images. The TBR was obtained as the ratio of the mean counts per pixels in the 2 ROIs. Then Tc-99m sestamibi retention index (RI) in the T was determined by dividing the D-TBR by the E-TBR. Afterwards, NACT response was assessed pathologically or clinically in inoperable disease. Scintigraphic sensitivity for correct prediction of T presence after NACT was 81% (17/21), whereas specificity for correct prediction of T absence was 100% (3/3). In LABC, 3 patients had a pathological complete response: first RI was high (>0.56) in all 3, while no T uptake was visible on the second scintigraphy. Eighteen patients did not show a pathological complete response: in 5, both first and second RI were low (</=0.56); 9 had high first RI but low second; 4 had high first RI and no T detected on the second scan. In IBC, the only patient with a clinical complete response had both first and second RI high, whereas the 2 non-responsive pts had both first and second RI low. These results indicate that Tc-99m sestamibi scintimammography can predict LABC and IBC response to NACT. The scintigraphy protocol, including 2 studies before and after NACT, is useful for detecting intrinsic and acquired chemoresistant BC in vivo, which is important for planning therapy and predicting prognosis.

Comparison of 99mTc-Sestamibi Scintimammography and Dynamic MR Imaging as Adjuncts to Mammography in the Diagnosis of Breast Cancer

To compare the diagnostic accuracy of planar 99mTc-sestamibi scintimammography with dynamic contrast-enhanced MRI (CE-MRI) on the basis of histopathologic results, and to determine the clinical value of these methods as adjuncts to mammography. A total of 90 consecutive women with 111 histopathologically verified breast lesions were enrolled in the study. Patients underwent scintimammography and CE-MRI in addition to mammography. Each finding was classified on a BI-RADS-like five-point rating scale describing the degree of suspicion for malignancy, and all findings were correlated with the histopathological results. The overall sensitivity/specificity/accuracy was 85%/59%/78% for mammography, 94%/47%/80% for CE-MRI, and 82%/75%/80% for scintimammography, respectively. CE-MRI showed higher sensitivity (p = 0.008), but its specificity was lower than scintimammography (p = 0.049). Using ROC analysis, significant improvement ( p = 0.034) was found between mammography and the combination of mammography + CE-MRI, while mammography + scintigraphy showed no higher diagnostic accuracy than mammography alone. If high sensitivity and spatial resolution are needed, CE-MRI is to be preferred in clinical practice as an adjunct to mammography, rather than scintigraphy.

Comparison of 99mTc-Sestamibi scintimammography and dynamic MR imaging as adjuncts to mammography in the diagnosis of breast cancer

Purpose: To compare the diagnostic accuracy of planar 99mTc-sestamibi scintimammography with dynamic contrast-enhanced MRI (CE-MRI) on the basis of histopathologic results, and to determine the clinical value of these methods as adjuncts to mammography. Material and Methods: A total of 90 consecutive women with 111 histopathologically verified breast lesions were enrolled in the study. Patients underwent scintimammography and CE-MRI in addition to mammography. Each finding was classified on a BI-RADS-like five-point rating scale describing the degree of suspicion for malignancy, and all findings were correlated with the histopathological results. Results: The overall sensitivity/specificity/accuracy was 85%/59%/78% for mammography, 94%/47%/80% for CE-MRI, and 82%/75%/80% for scintimammography, respectively. CE-MRI showed higher sensitivity ( p = 0.008), but its specificity was lower than scintimammography ( p = 0.049). Using ROC analysis, significant improvement ( p = 0.034) was found between mammography and the combination of mammography + CE-MRI, while mammography + scintigraphy showed no higher diagnostic accuracy than mammography alone. Conclusion: If high sensitivity and spatial resolution are needed, CE-MRI is to be preferred in clinical practice as an adjunct to mammography, rather than scintigraphy.

Results of clinical trials with SPEM

Abstract X-ray mammography represents the principal tool for breast cancer screening, but has several limitations. Due to the low specificity of X-ray mammography, many more biopsies are performed than are necessary. More than 60% of breast biopsies performed because of suspicious X-ray mammograms yield a diagnosis other than cancer. In women with X-ray dense breast tissue, X-ray mammography can miss as many as 20% of cancers. Several studies suggest that combining 99mTc Sestamibi Scintimammography (SM) with X-ray mammography can increase the accuracy of breast imaging in selected populations. The principal limitation of prone-position scintimammography (PSM) using a standard Anger gamma camera is low sensitivity for subcentimeter cancers (i.e., stages T1a and T1b). Detecting these small cancers is extremely important clinically, since removal of the cancers at these early stages is thought to represent the best opportunity for cure. Our group constructed a high spatial resolution detector specifically dedicated to SM, the Single Photon Emission Mammography (SPEM) camera. Unlike conventional Anger gamma cameras, the SPEM camera incorporates a high spatial resolution position-sensitive photomultiplier tube, coupled to an array of scintillating crystals. The compactness of the SPEM camera allows breast compression to be implemented in a cranio-caudal view, facilitating comparison to X-ray mammograms taken in the same position. Clinical results so obtained have demonstrated increased diagnostic sensitivity in sub-centimeter tumors (80% for SPEM vs 50% with PSM). Factors contributing to this increased sensitivity include improved signal-to-noise ratio (SNR). For sub-centimeter cancers, SPEM SNR values were consistently much higher than those of PSM. Classic detectability studies have demonstrated that an SNR value >5 is required for reliable detection of cancers. For subcentimeter cancers, only the SPEM attained or exceeded this minimum threshold. The results showed that compression, which optimizes resolution by reducing lesion-to-collimator distance, and increases planar image contrast by reducing signal and attenuation from interposed normal breast tissue, plays a fundamental role in the visualization of subcentimeter breast cancers.

A review of the cost-effectiveness of Tc-99m sestamibi scintimammography in diagnosis of breast cancer in Taiwanese women with indeterminate mammographically dense breast

In general, biopsy is the preferred management method for women with indeterminate mammographically dense breasts. In this review, we describe a decision analysis model comparing technetium-99m methoxyisobutylisonitrile (Tc-99m sestamibi) scintimammography and excisional biopsy as breast cancer evaluation strategies for hypothetical cohorts of estimated 16,000–40,000 women with indeterminate mammographic probability of malignancy because of mammographically dense breasts. In cost-effectiveness analysis, quantitative decision tree sensitivity analysis was used to compare the conventional excision biopsy alone strategy (strategy A) with decision strategy for screening with Tc-99m sestamibi scintimammography before excision biopsy (strategy B) after an indeterminate mammogram. Strategy B showed a cost saving of US dollars 649,600–1,624,000 in reducing the cost of unnecessary biopsies. The total cost of strategy B showed a cost saving of US dollars 123,075–307,776 compared to strategy A. The analysis data indicate that Tc-99m sestamibi scintimammography can save the cost of unnecessary biopsies in Taiwanese women with non-diagnostic mammogram because of mammographically dense breasts.

Single static view 99mTc-sestamibi scintimammography predicts response to neoadjuvant chemotherapy and is related to MDR expression

We examined the relevance of a pre-treatment single static view 99mTc-sestamibi scintimammography and expression of multidrug resistance proteins as predictors of response to neoadjuvant chemotherapy for invasive breast cancer. Forty-five patients affected by primary breast cancer underwent clinical examination, mammography, sonography, 99mTc-sestamibi scintimammography, and biopsy for histopathological diagnosis before neoadjuvant chemotherapy. Expression of MDR1 and MRP mRNA were determined by RT-PCR on fine-needle aspirations. Following completion of anthracycline-based chemotherapy, clinical, mammographic, sonographic and pathological responses were determined. 99mTc-sestamibi scintimammography predicted the reduction of tumor size measured by sonography and the pathological response according to Sataloff classification (p<0.05) and tend to predict pathological response according to Chevallier (p<0.1). A negative 99mTc-sestamibi scintimammography predicted chemoresistance with a specificity of 100%. Uptake of 99mTc-sestamibi was inversely correlated to the expression of MDR1 (p<0.05) in invasive ductal carcinoma. A pre-treatment single-view 99mTc-sestamibi scintimammography is an excellent predictor of MDR1 chemoresistance and was highly specific of a lack of pathological response to chemotherapy.

52. 99mTc sestamibi scintimammography in the diagnosis of palpable benign breast masses

52. 99mTc sestamibi scintimammography in the diagnosis of palpable benign breast masses

The role of Tc99m-sestamibi scintimammography in combination with the triple assessment of primary breast cancer

Aim: The aim of this study was to evaluate if Tc99m-sestamibi scintimammography in addition to the triple assessment consisting of clinical examination, mammography, breast ultrasonography and fine needle aspiration cytology (FNA) enhances the diagnosis of breast cancer and helps in avoiding unnecessary operative biopsies. Methods: Pre-operational scintimammography was performed within 2 weeks of operation to 46 consecutive patients with abnormal findings in clinical breast examination, mammography or ultrasonography. Three patients had abnormalities in both breasts. Histological diagnosis was obtained in all 49 cases. Results: The histological diagnosis was benign in 18 (37%) cases and malignant in 31 (63%) cases. The overall sensitivity of scintimammography was 77% and the specificity was 61%. The sensitivity of scintimammography was 95% in invasive ductal carcinoma, 50% in invasive lobular carcinoma and 25% in ductal carcinoma in situ. Scintimammography showed 100% sensitivity in cases with invasive carcinoma, with highly suspicious findings for malignancy in the other examinations. The sensitivity was 63% in cases with indeterminate or contradictory findings in mammography, ultrasonography and FNA. Conclusions: Adding scintimammography to the triple assessment does not seem to be helpful in the diagnosis of breast abnormalities because of low sensitivity in malignant cases with a challenging diagnosis by mammography, ultrasonography and FNA, and because of low overall specificity.

Comparison of Technetium-99m Methoxyisobutylisonitrile Scintimammography and Ultrasonography in the Diagnosis of Breast Cancer in Patients with Mammographically Dense Breast

The main purpose of this study was to compare the utility of technetium-99m methoxyisobutylisonitrile (Tc-99m sestamibi) scintimammography with that of ultrasonography for diagnosis of breast cancer in 32 female patients with indeterminate mammographic probability of malignancy because of mammographically dense breast. All breast masses were removed and histopathological diagnosis was obtained in all cases. The results showed 20 of 24 cases of breast carcinoma detected on Tc-99m sestamibi scintimammography. Only one out of eight patients with benign breast lesion had abnormal scintimammographic finding. Ultrasonography diagnosed 22 of the 24 cases of breast carcinoma. However, five out of eight patients with benign breast lesion had positive ultrasonographic findings. In differentiating malignant and benign breast tumors in mammographically dense breast, the diagnostic sensitivities were 83 and 92%, specificities were 88 and 38%, and accuracies were 84 and 78% for Tc-99m sestamibi scintimammography and ultrasonography, respectively. Ultrasonography showed a nonsignificantly higher sensitivity (p<0.05), but lower specificity, with more false-positive diagnoses made on ultrasonography. Due to its higher sensitivity, ultrasonography is more suitable for screening breast masses. However, Tc-99m sestamibi scintimammography exhibited significantly higher specificity (p<0.05) and accuracy in detecting malignant breast tumors in the current study. We conclude that Tc-99m sestamibi scintimammography is a safe and useful diagnostic method for detection of breast cancer in patients with nondiagnostic mammogram because of mammographically dense breast.

The Clinical Utility of Tc-99m Sestamibi Scintimammography in Detecting Multicentric Breast Cancer

The ability to recognize multicentric breast cancer preoperatively would assist in identifying appropriate candidates for breast conservation surgery. Tc-99m scintimammography (SMM) is an adjunct to conventional mammography in identifying selected patients with breast cancer. The purpose of this study is to report the utility of SMM in identifying patients with multicentric breast cancer. Breast cancer patients treated by mastectomy who underwent a preoperative SMM between 1992 and 1999 were identified using the institution's Tumor Registry. The pathology report of each patient was reviewed for multicentric disease defined as an additional focus of cancer within a different quadrant of the breast or greater than 2.5 cm from the dominant tumor mass. Each patient's preoperative SMM was reviewed and compared with the pathologic findings to obtain correlative data. Fifty-eight women treated by mastectomy had preoperative SMM (age range 35-78 years; median 52 years). Pathology revealed infiltrating ductal carcinoma in 49 patients (84.5%), infiltrating lobular carcinoma in five patients (8.6%), ductal carcinoma in situ in three patients (5.1%), and colloid carcinoma in one patient (1.7%). Multicentric disease was present in the specimens of eight patients for a prevalence of 10.3 per cent. SMM was positive for uptake in 36 of 58 patients (sensitivity 62.1%). The sensitivity, specificity, positive predictive value, and negative predictive value of SMM in the detection of multicentric disease were 62.5, 96, 71, and 94 per cent, respectively. Although the overall sensitivity of SMM in the detection of breast cancer is superior to that of conventional mammography and physical examination in identifying multicentric breast cancer it is not an accurate modality for detecting multicentric disease in this study group. However, it may have limited applications in specific cases.

The role of 99m Tc-sestamibi scintimammography and colour Doppler ultrasonography in the evaluation of breast lesions.

In the present study we evaluated comparatively the diagnostic value of mammography, of 99mTc-sestamibi scintimammography (sestamibi-SC) and of colour Doppler ultrasonography (CD-US) in 116 breast lesions. Diagnosis was based on histopathological examination. Overall, out of 86 malignant tumours, 80 (93%) and 75 (87%) had a positive sestamibi-SC and positive CD-US, respectively. Out of 30 benign lesions, 25 (83%) and 26 (87%) had a negative sestamibi-SC and negative CD-US respectively. The true positive results were similar in palpable and in non-palpable lesions for both methods. Out of 19 non-palpable malignant tumours, mammography confirmed malignancy in only one case (5%), which was significantly lower than the results obtained by sestamibi-SC (89%; Px0.0001) and by CD-US (74%; P=0.0001). In palpable malignant tumours, by using mamography, true positive results were obtained in 54/67 (80.5%) patients, which was significantly lower than the results obtained by sestamibi-SC (94%; P=0.03) and marginally different to the results obtained by CD-US (91%; P=0.13). It is concluded that sestamibi-SC and CD-US are useful tools in clarifying the nature of breast lesions in cases with doubtful mammography. The clinical value of these diagnostic procedures in guiding subsequent therapeutic interventions requires further investigation.

Tc 99m-Sestamibi scintimammography in the differentiation of benign and malignant breast microcalcifications

The capability of the mammography-scintimammography combination to distinguish between benign and malignant isolated clusters of breast microcalcifications is discussed. Scintimammography using Tc 99m-Sestamibi was performed in 97 women with an isolated cluster of microcalcifications on mammograms. Seventy-two women had final histopathologic diagnoses (24 cancer and 48 benign pathology). The other 25 patients had follow-up to 3 years. The results of mammography, scintimammography and mammography-scintimammography combination were divided into five groups, based on the suspicion of malignancy. The sensitivity, specificity, false negative fraction, false positive fraction, predictive positive value, predictive negative value and diagnostic accuracy were calculated varying the diagnostic threshold. The Receiver Operating Characteristic (ROC) statistical technique was employed to compare the diagnostic value of mammography to mammography-scintimammography combination. The area under the ROC curves was calculated by the Wilcoxon statistic without any hypothesis on data distribution. The detected difference between areas under the mammography ROC curve (area=0.854, standard error=0.049) and mammography-scintimammography ROC curve (area=0.897, standard error 0.033) was statistically significant (P>0.05, one tail). The area under a ROC curve represents the probability that a randomly chosen diseased or non-diseased subject could be correctly classified. From this point of view this paper demonstrates that, if properly used, scintimammography can add to mammography in the characterization of an isolated cluster of microcalcifications, even if it is not able to replace FNAB and core biopsy.

Detection of resistance to anthracyclines(A)-based neoadjuvant chemotherapy (NACT) in locally advanced (LABC) and inflammatory breast cancer (IBC) with tc-99m sestamibi scintimammography (SM)

Detection of resistance to anthracyclines(A)-based neoadjuvant chemotherapy (NACT) in locally advanced (LABC) and inflammatory breast cancer (IBC) with tc-99m sestamibi scintimammography (SM)

P21. A comparison of the accuracy of reporting axillary lymph node involvement using 99mTc-sestamibi and 99mTc-oxidronate scintimammography in breast cancer patients

A Comparison of the Accuracy of Reporting Axillary Lymph Node Involvement Using 99mTc.Sestamibi and 99mTc.Oxidronate Scintimammography in Breast Cancer Patients

The Usefulness of MIBI Scanning to Detect Underlying Carcinoma in Women with Acute Mastitis

The efficacy of Tc-99m sestamibi scintimammography in the detection of breast carcinoma has been proven in previous studies. In this study we evaluated the influence of active mammary inflammation on Tc-99m sestamibi scintimammography and its ability to detect breast malignancy in the presence of this condition. Twenty-one women with acute nonpuerperal mastitis underwent breast scintimammography using Tc-99m sestamibi. Their mean age was 49.6 years. In 15 women the scan was positive, 2 suffered from inflammatory carcinoma of the breast, and all the other women had acute mastitis. Six patients had a negative scan, and in all of them, acute mastitis was diagnosed. Total accuracy, sensitivity and specificity in the detection of breast mastitis were 62%, 68%, and 88%, respectively. Scintimammography in patients with acute inflammation of the breast is frequently positive in the absence of malignant condition, therefore it should not be used during acute mastitis for the detection of breast cancer.

Double-phase Tc-99m Sestamibi Scintimammography To Assess Angiogenesis and P-glycoprotein Expression in Patients With Untreated Breast Cancer

This study evaluated the relation of Tc-99m sestamibi (MIBI) uptake and washout in untreated breast cancer with immunohistochemically determined angiogenesis and P-glycoprotein expression. Thirty-one patients with untreated breast cancer were studied prospectively. Tc-99m MIBI scintigraphy and immunohistochemical analyses of angiogenesis and P-glycoprotein expression were used to evaluate surgically removed tumor tissues. Anterior and both lateral planar images were acquired 10 and 180 minutes after intravenous injection of 740 MBq (20 mCi) Tc-99m MIBI. The tumor-to-normal breast ratio (T:N) and washout index (early T:N - late T:N divided by early T:N) were calculated. A significant correlation was found between angiogenesis and T:N at early and late images. Pearson's correlation coefficients and probability values were r = 0.54, P = 0.002 at early images and r = 0.47, P = 0.008 at late images. The T:N of both early and late images were not different among different groups of P-glycoprotein expression (P = 0.367 and P = 0.113, respectively), although the washout index was significantly different among the groups (P = 0.001). A strong correlation was found between the washout index and P-glycoprotein expression (r = 0.67, P < 0.01). Double-phase scintimammography to assess the early tumoral uptake and washout of Tc-99m MIBI can be used as a simple functional test for in vivo imaging of tumoral angiogenesis and P-glycoprotein expression in patients with untreated breast cancer.

The role of 99mTc-sestamibi and other conventional radiopharmaceuticals in breast cancer diagnosis

The wide availability and the extensive use of screening mammography have resulted in an earlier diagnosis of breast cancer and in a significant reduction in the relative risk of dying from this disease. Despite technical improvements and major advantages associated with the use of mammography (and breast ultrasound), this procedure has some limitations in clinical practice, especially in women with dense breast tissue, implants, severe dysplastic disease, or significant architectural distortion following breast surgery or radiation therapy. Different noninvasive imaging techniques have been evaluated to overcome these limitations. Nuclear medicine also has been actively involved in the detection of breast cancer, using various types of radiopharmaceuticals. Currently, there are three radiotracers commonly used for breast imaging or scintimammography in either clinical practice or research: 99mTc-sestamibi and 99mTc-tetrofosmin (two agents used for myocardial perfusion imaging) and 99mTc-MDP (methylene diphosphonate, used for bone scintigraphy). 99mTc-sestamibi was the first radiopharmaceutical to be approved by the FDA for scintimammography. Several prospective studies have shown that the overall sensitivity of 99mTc-sestamibi scintimammography in detection of breast cancer was 85%, the specificity was 89%, and the positive and negative predictive values were 89% and 84% respectively. Similar numbers have been demonstrated for 99mTc-tetrofosmin and 99mTc-MDP scintimammography. Although not indicated as a screening procedure for the detection of breast cancer, scintimammography may play a useful and significant role in various specific clinical indications such as nondiagnostic or difficult mammography, and evaluation of high-risk patients, tumor response to chemotherapy, and axillary lymph node metastatic involvement.

The usefulness of Tc-99m sestamibi scintimammography in the diagnosis of squamous cell carcinoma of the breast.

Primary squamous cell carcinoma of the breast is very rare, and diagnosis of a benign lesion often is made by mammography or ultrasonography in these cases. The authors present a case of squamous cell breast carcinoma in which Tc-99m sestamibi scintimammography was very useful in the evaluation of the disease.