Optimization of X-ray mammography and technetium-99m methoxyisobutylisonitrile scintimammography in the diagnosis of non-palpable breast lesions

The purpose of this study was to evaluate the contribution of technetium-99m methoxyisobutylisonitrile (MIBI) scintimammography to the early diagnosis of breast cancer in 78 patients with non-palpable breast lesions detected by mammography. In all cases biopsy was indicated and they were classified into three groups according to the mammographic findings: high (28), intermediate (30) and low (20) mammographic probability of malignancy. Histological diagnosis confirmed 37 benign and 41 malignant lesions. In the high-probability group ^99mTc-MIBI scintimammography changed the four false-positives into true negatives at the expense of two false-negatives; in the intermediate group it changed nine of the 17 false-positives into true-negatives at the expense of one false-negative, and in the low-probability group it changed five of the 16 false-positives into true-negatives without false-negatives. Applying scintimammography to patients included in the intermediate and low-probability groups together, 14 of the 33 mammographic false-positives were changed into true-negatives with 1 false-negative; thus, 41% of the unnecessary biopsies would have been avoided. When MIBI scintimammography was applied to the low-probability group, the negative predictive value was 100% and the unnecessary biopsies would have been reduced by 31%. Received 10 November 1997 and in revised form 19 January 1998     

乳腺肿块~(99m) Tc-MIBI双时相显像与X线钼靶对照研究

目的：探讨~(９９ｍ)ＴＣ－ＭＩＢＩ双时相乳腺显像和乳腺钼靶的联合应用对提高患者术前诊断准确性的价值。材料和方法：对疑为乳腺癌的 ３４名患者术前行钼靶检查和~(９９ｍ)Ｔｃ－ ＭＩＢＩ双时相乳腺显像。乳腺钼靶：双乳分别行轴位（头足位）和侧位摄片。乳腺双时相核素显像采用平面显像行正位、双侧斜位、俯卧位时双侧乳腺侧位。所有病例均于两项检查后两星期内行手术获得病理诊断。结果：~(９９ｍ)Ｔｃ－ ＭＩＢＩ乳腺双时相显像示：乳腺的早期和延迟显像一致。恶性病变早期和延迟相的平均Ｔ／Ｎ值分别为１８０±０．６８、１．６４±０．４２,两者Ｐ＞０．０５。~(９９ｍ)Ｔｃ－ＭＩＢＩ乳腺双时相显像敏感性为８８％,特异性为７６％,准确性为８２％。钼靶检查：良性病变诊断的８例中,一例为恶性病变（浸润性导管癌）;病变性质无法确定的１４例中,６例为恶性病变（浸润性导管癌３例,浸润性腺癌２例,鳞癌１例）;恶性病变诊断的１２例中２例为良性病变。钼靶检查病变性质无法确定的１４例中,乳腺双时相显像诊断正确为１２例。结论：~(９９ｍ) Ｔｃ－ＭＩＢＩ乳腺双时相显像和钼靶检查对乳腺肿块的诊断和鉴别诊断中有各自的特点。在临床实践中合理的诊断程序有助于提高诊断准确率,减少不     

Comparative value of 99mTc-sestamibi scintimammography and sonography in the diagnostic workup of breast masses

OBJECTIVE: This study was conducted to assess the relative roles of 99mTc-sestamibi scintimammography and sonography in the evaluation of breast lesions that are indeterminate or suspicious on mammography or clinical examination. SUBJECTS AND METHODS: Twenty-five patients with 33 biopsy-proven breast lesions underwent both scintimammography and sonography. Lesions were categorized as benign or requiring biopsy on the basis of the absence or presence of a focus of increased activity on scintimammography and the shape, orientation, and echogenicity of the lesion on sonography. RESULTS: Sensitivity and specificity in detecting breast cancer were 92% and 95%, respectively, for scintimammography and 100% and 48%, respectively, for sonography. The higher specificity of scintimammography was statistically significant (p < 0.01). CONCLUSION: Although the overall accuracy of 99mTc-sestamibi scintimammography in the diagnosis of breast cancer was high, it has several disadvantages in comparison with sonography. Scintimammography has a slightly higher false-negative rate for breast cancer, is unable to reveal cysts, is more expensive, takes longer to perform, and involves ionizing radiation. For these reasons, scintimammography with 99mTc-sestamibi is unlikely to either replace sonography or be frequently used in addition to sonography.     

Contribution of 99mTc-anti-carcinoembryonic antigen antibody and 99mTc-sestamibi scintimammography in the evaluation of high risk palpable breast lesions

Mammography is the screening test of choice for breast cancer. Its low specificity leads to a large number of unnecessary biopsies. Scintimammography, with either Tc-sestamibi (MIBI) or Tc-anti-carcinoembryonic antigen (CEA) Fab', has been proposed as a non-invasive test to lower the high false positive rate of mammography in certain patients. The two agents have not been compared, nor has their combined application been evaluated. We performed a prospective, non-randomized, open-label, single-centre study of 32 women with clinically and mammographically suspected breast cancer [Breast Imaging Reporting and Data System (BI-RADS, American College of Radiology) 4 or 5]. All patients underwent Tc-MIBI and Tc-anti-CEA Fab' scintimammography, and the results were correlated with histopathology. Overall, the accuracies for MIBI and CEA scans were 90.3% (28/31) and 77.4% (24/31), respectively. The probability of disease after mammography was 0.939+/-0.081 (95% confidence interval, CI). The post-mammography probabilities after positive MIBI or CEA scan were 0.965 and 0.960, respectively, and after negative MIBI or CEA scan 0.750 and 0.875, respectively. None of the above differences is significant. The post-test probability when both scans were positive (irrespective of which was performed first) was 0.977. It can be concluded that there are indications that scintimammography with Tc-MIBI is superior to that with Tc-anti-CEA Fab' when these tests are used as screening tests for breast cancer. However, mammography remains the screening test of choice for highly suspicious clinically palpable breast lesions. In this group of patients, the application of scintimammography with either Tc-MIBI or Tc-anti-CEA Fab' (alone or in combination) offers no additional advantage.     

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.     

Diagnosis of breast cancer: contribution of US as an adjunct to mammography.

PURPOSE: To determine the value of ultrasonography (US) as an adjunct to mammography for the diagnosis of breast cancer. MATERIALS AND METHODS: In a 2-year prospective study, 4,811 mammograms were classified according to level of suspicion of malignancy. Targeted US was performed to analyze (a) circumscribed lesions, possibly cysts; (b) palpable lesions visible at mammography; (c) palpable lesions not visible at mammography; and (d) nonpalpable lesions visible at mammography. After US was performed in 1,103 cases (23%), cases were reclassified for level of suspicion. RESULTS: In 338 cases, breast cancer was diagnosed. The sensitivity of mammography for all 4,811 cases was 83%; the specificity was 97%. After US, the combined sensitivity increased to 91%, with a specificity of 98%. The increase was significant (P < .001). The increase in sensitivity was highest among women younger than 50 years. The positive predictive value for mammography was high (72%), which reflects a high threshold for biopsy; this may have augmented the yield of US. CONCLUSION: The use of US as an adjunct to mammography resulted in an increase in diagnostic accuracy. Its contribution to the diagnosis of breast cancer in this study was 7.4%.     

The use of echography and US-guided percutaneous puncture in addition to mammography for the detection of malignant breast tumors]

At present, mammography is the most effective means to detect breast cancers, especially in the early stages. However, it lacks sensitivity and specificity in women with dense breasts. Moreover, indeterminate lesions are often seen on mammograms, which should undergo further examination before surgery. Due to recent improvement in the technique--i.e., the use of high-resolution 10-MHz transducers--US can now detect also nonpalpable breast lesions, about 1 cm phi. Fine-needle biopsy (FNB) under US guidance, which is complementary to US, allows a correct diagnosis of malignancy in a high number of cases. A total of 1821 women with indeterminate lesions at mammography underwent US, and 491 of them underwent US-guided FNB, in the Leno Hospital (Brescia, Italy), in the period 1988-90. Thirty-one breast cancers which had been missed at mammography and clinical examination were found. Three cases were carcinomas in situ, 23 invasive cancers were classified as pathological stage T1, and 15 cases had no axillary lymph node involvement. The routine use of US and FNB in addition to mammography when indeterminate lesions are seen on mammograms and in women with dense breasts may significantly reduce the number of both false-negative cases at mammography and unnecessary biopsies.     

Comparison of dynamic MR imaging of the breast and sestamibi scintimammography for evaluation of indeterminate mammographic lesions

The aim of this study was to compare Tc-99m sestamibi scintimammography and dynamic contrast-enhanced MR imaging for the evaluation of indeterminate mammographic lesions. Forty patients with questionable mammographic findings were included in a prospective study. Thirty lesions were non-palpable. Mean lesion size was 1.6+/-0.7 cm (range 0.5-3.5 cm). Scintigraphy was considered as malignant when focal tracer accumulation was present. In MR imaging, lesions were classified according to their signal intensity time course: no enhancement or steady enhancement with low signal intensity (M0); steady enhancement with high signal intensity (M1); or rapid enhancement with plateau (M2) or washout (M3). Lesions classified as M2 or M3 were considered as suspicious for malignancy. Histopathologic evaluation was performed in 24 lesions. In 16 cases lesions were classified as benign from follow-up examinations (mean 24 months). Malignancies were proven in 14 patients (9 invasive carcinomas, 5 ductal carcinoma in situ). Sensitivity of MR imaging was 12 of 14 (86%) and sensitivity of scintimammography was 8 of 14 (57%). One of 26 benign lesions was false positive at MR imaging. Scintigraphy showed no false-positive results. In conclusion, magnetic resonance imaging provided high accuracy in evaluation of indeterminate mammographic lesions. Sensitivity of scintimammography was too low in detecting small carcinomas.     

Positive predictive value of 99mTc sestamibi scintimammography in patients with non-palpable,mammographically detected,suspicious, breast lesions

The purpose of this study was to analyse whether the use of Tc sestamibi scintimammography improves the positive predictive value of X-ray mammography. A series of 73 women (median age 51 years, range 35-79 years) with non-palpable, mammographically suspicious, breast lesions was reviewed. There were 41 (56.2%) pre-menopausal, and 32 (43.8%) post-menopausal women. All patients underwent sestamibi scintimammography prior to open breast biopsy. Definitive histology showed breast cancer (pT1a=1 (1.9%), pT1b=47 (90.4%), pT1c=4 (7.7%)) in 52 (71.2%) patients, and benign breast lesions in 21 (28.8%). Patients with cancer were significantly older (P <0.01), while the greatest dimension (size) of the excised lesion did not differ (8.47+/-1.51 vs 8.30+/-1.53 mm; P =0.66) between the two groups. Overall, the positive predictive values of mammography and sestamibi scintimammography were 71.2% and 95.7%, respectively (P =0.004). Patients with false positive mammography were significantly younger than those in whom cancer was diagnosed correctly (45.35+/-7.56 vs 53.96+/-10.60 years; P =0.001), while age did not affect the sensitivity of sestamibi scintimammography, which reached 100% in patients with breast lesions > or =8 mm in size. In this subgroup the positive predictive value of mammography, sestamibi scintimammography, and mammography+sestamibi scintimammography together were 63.4%, 95.1% (P =0.001), and 97.6%, respectively, and the majority of the patients with benign lesions (13 of 15 (86.7%)) could have avoided biopsy. It is concluded that the use of Tc sestamibi scintimammography in conjunction with mammography may potentially reduce unnecessary surgical procedures, and should be performed in all patients with mammographically suspicious breast lesions of 8 mm or greater in size.     

99Tcm-MIBI scintimammography in the evaluation of breast lesions and axillary involvement: a comparison with mammography and histopathological diagnosis.

The aim of this prospective study was to determine the diagnostic value of prone lateral 99Tcm-MIBI scintimammography in the detection of primary breast cancer and axillary lymph node involvement in patients with breast lesions. We evaluated 83 palpable and 22 non-palpable lesions in 77 consecutive patients with a clinically palpable mass and/or suspicious mammographic finding. Early and late scintimammograms were performed after the intravenous injection of 740 MBq 99Tcm-MIBI. The overall sensitivity of both scintimammography and mammography in the detection of primary breast cancer was 94%. The overall specificity was 84% and 56% for scintimammography and mammography respectively. In the patients with palpable masses, the sensitivity of scintimammography was 97% and the specificity was 84%; in those with non-palpable masses, the sensitivity was 35% and the specificity 100%. For the detection of axillary lymph node involvement, the sensitivity and specificity of scintimammography were 68% and 93% respectively. However, conventional mammography showed 37% sensitivity and 86% specificity. In conclusion, scintimammography is an accurate and clinically valuable tool for evaluating palpable and non-palpable breast abnormalities. In addition to its high sensitivity, it improves the specificity of mammography both in the evaluation of breast masses and in the detection of axillary involvement.     

Can scintimammography with (99m)Tc-MIBI identify multifocal and multicentric primary breast cancer?

Scintimammography with (99m)Tc-MIBI has been shown to be an effective adjunct to imaging of the breast with mammography. Uptake of (99m)Tc-MIBI is particularly high in sites of non-calcified cancer and ductal carcinoma in situ (DCIS), and as a consequence it may be possible to use this method of imaging in identifying multifocal or multicentric disease. The aim of this study was to evaluate the efficacy of preoperative scintimammography in the detection of multifocal and multicentric breast cancer and compare these results with mammography. A retrospective review was performed of 353 women imaged with (99m)Tc-MIBI as part of the clinical assessment of their suspected primary breast cancer. The results of the scintimammography and mammography were then compared with the final pathological diagnosis obtained after mastectomy in all patients. Histopathological assessments of breast tissue from mastectomy confirmed 40 women (12%) had multifocal (34) or multicentric (six) breast cancer. Scintimammography correctly identified 39 of these cancers and the multifocal or multicentric character of the cancer was identified in 22 (52%) of these patients. Anatomical imaging performed in all 40 patients including 25 with mammography alone, mammography and ultrasound in 11 cases and ultrasound alone in four patients. Anatomical imaging identified cancer to be present in 28 patients (70%) and the combination of mammography and ultrasound identified correctly that the cancer was multifocal or multicentric in eight patients (22%). In this study scintimammography was able to identify more cases of multifocal and multicentric cancer than mammography and/or ultrasound. In patients where pre-operative identification of multicentric or multifocal disease can alter treatment scintimammography may be a useful investigative tool.     

Double-phase 99mTc-sestamibi scintimammography and trans-scan in diagnosing breast cancer.

The goal of our study was to assess the value of both scintimammography with 99mTc-sestamibi (SMM) and trans-scan (T-scan) in detecting breast cancer. METHODS: A total of 121 women were evaluated by palpation, mammography, SMM and T-scan. SMM was performed in the prone, breast dependent position. Immediate and delayed views (double-phase) were obtained. T-scan is a new breast imaging method that maps noninvasively the distribution of tissue electrical impedance and capacitance. RESULTS: SMM had 88.9% sensitivity, 88.4% specificity and 88.4% accuracy in detecting breast cancer. SMM had 100% sensitivity in detecting breast tumors >1 cm and only 66% sensitivity in detecting tumors <1 cm. T-scan had 72.2% sensitivity and 67% specificity in detecting breast cancer. It detected one more breast cancer than SMM, at the expense of 27 additional false-positive results. CONCLUSION: Double-phase SMM was sensitive and specific in detecting breast cancer. This method may reduce the rate of negative breast biopsies in tumors >1 cm. T-scan was only moderately accurate in detecting breast cancer. Its addition to SMM did not improve significantly the rate of breast cancer detection. However, because of its complete noninvasiveness, large-scale applicability and low cost, T-scan deserves further refining.     

Incidental findings on sonography of the breast: clinical significance and diagnostic workup.

OBJECTIVE: The purpose of this study was to determine how often physician-performed high-resolution sonography can detect nonpalpable breast lesions not revealed by mammography. A sonographic classification scheme was tested for its accuracy in predicting malignancy of incidentally detected breast lesions. SUBJECTS AND METHODS: Six thousand one hundred thirteen asymptomatic women with breast density grades 2-4 and 687 patients with palpable or mammographically detected breast masses underwent sonography as an adjunct to mammography. All sonographically detected, clinically and mammographically occult breast lesions that were not simple cysts were prospectively classified into benign, indeterminate, or malignant categories. Diagnoses were confirmed by sonographically guided fine-needle aspiration or core needle biopsy. RESULTS: In 6113 asymptomatic women, 23 malignancies in 21 patients were detected with sonography only (prevalence, 0.31%). Five additional malignant lesions were found in patients with a malignant (n = 3) or a benign (n = 2) palpable or mammographically detected index lesion. The mean size of invasive malignancies detected only by sonography was 9.1 mm, which was not significantly different from the mean size of invasive cancers detected by mammography (p = .07). The sensitivity of the prospective sonographic classification for malignancy was 100%, and the specificity was 33.5%. CONCLUSION: The use of high-resolution sonography as an adjunct to mammography in women with dense breasts may lead to detection of a significant number of otherwise occult malignancies that are no different in size from nonpalpable mammographically detected lesions. Prospective classification of these lesions based on sonographic characteristics results in a significant reduction in number of unnecessary biopsies performed.     

立体定位穿刺活检诊断乳腺灶性病变的临床价值（附52例分析）

目的：评价乳腺立体定位穿刺活检对乳腺局灶性病变的诊断价值。方法：应用意大利IMS公司生产的钼靶乳腺机及配套的立体定位穿刺活检装置及日本富士公司生产的计算机X线影像处理系统对3200例病人行双乳轴、侧斜位数字化乳腺摄片检查,对检出的可疑病灶行立体定位穿刺活检,并与手术后病理检查结果对照。结果：对检出的52例乳腺局灶性病变行立体定位穿刺活检,检出乳腺癌33例（63．46％）,其中原位癌9例,良性病变19例（36．54％）。结论：乳腺立体定位穿刺活检是目前诊断早期乳腺癌的有效方法。     

The value of early and double phase 99Tcm-sestamibi scintimammography in the diagnosis of breast cancer

The aim of this study was to assess the additional value of early and double phase scintimammography (SMM) with 99Tcm-sestamibi in the detection of breast cancer following initial evaluation by palpation and mammography. Altogether, 322 women with breast lesions evaluated prospectively by palpation, fine-needle aspiration and mammography were assigned a malignancy risk according to the results. Scintimammography was performed in all patients in the prone breast dependent position. Immediate and delayed views were obtained. Acquisition of immediate tracer uptake was termed 'early phase' SMM, whereas a combination of both immediate and delayed phase images was termed 'double phase' SMM. All patients underwent breast biopsy. Both early phase and double phase SMM detected eight of nine tumours in the low-risk group (88.8% sensitivity). In the uncertain cases (moderate-risk group), early phase SMM detected all malignant tumours, but double phase SMM missed one (92.3% sensitivity). In the high-risk group, early phase SMM missed two breast cancers (94.6% sensitivity) and double phase SMM missed four (89.2% sensitivity). Overall, early phase SMM had a sensitivity of 94.9% and a specificity of 80.2% in detecting breast cancer, whereas double phase SMM had a sensitivity of 89.8% and a specificity of 94.3%. Both methods had 100% sensitivity for tumours larger than 1 cm. In conclusion, SMM detected additional breast cancers following an initial evaluation by palpation, fine-needle aspiration and mammography. Our results suggest that double phase SMM is more specific than early phase SMM, although early phase SMM is more sensitive. Whether the interpretation of SMM results should rely on both early and delayed images, or early images alone, should be based on the relative risk of malignancy of the breast lesion as estimated by the initial evaluation.     

Scintimammography with technetium-99m methoxyisobutylisonitrile: results of a prospective European multicentre trial

The aim of the trial was to determine the diagnostic accuracy of scintimmammography with technetium-99m methoxyisobutylisonitrile (^99mTc-MIBI) in the detection of primary breast cancer and to verify its clinical usefulness. A total of 246 patients with a suspicious breast mass or positive mammogram were included in this prospective European multicentre trial. At 5 min and 60 min (optional) p.i. two lateral prone images were acquired for 10 min each; 30 min p.i. one anterior image was acquired for 10 min. There were 253 lesions (195 palpable and 58 non-palpable), in respect of which histology revealed 165 cancers and 88 benign lesions. Institutional and blinded read results were correlated to core laboratory histopathology results obtained during excisional biopsy. Diagnostic accuracy for the detection of breast cancer was calculated per lesion. The overall sensitivity and specificity of blinded read scintimammography were 71% and 69%, respectively. For palpable lesions, the sensitivity of blinded read and institutional read scintimammography was 83% and 91%, respectively. Sensitivity was not dependent on the density of the breast tissue. Invasive ductal and invasive lobular cancers showed similar sensitivity. The sensitivity and specificity of mammography were 91% and 42%, respectively, and did not depend on the tumour size. In 60% of false-negative mammograms, ^99mTc-MIBI was able to diagnose malignancy (true-positive). High-quality imaging with ^99mTc-MIBI has a high diagnostic accuracy for the detection of primary breast cancer. Used as a complementary method, scintimammography with ^99mTc-MIBI can help to diagnose breast cancer at an earlier stage in patients with dense breasts. Received 11 October and in revised form 12 December 1997     

Scintimammography in conjunction with ultrasonography for local breast cancer recurrence in post-mastectomy breast

The aim of this study was to compare the usefulness of (99)Tc(m)-methoxy-isobutyl-isonitrile (MIBI) scintimammography and ultrasonography, alone and in combination, for the detection of chest wall recurrence in the post-mastectomy breast. A total of 41 consecutive post-mastectomy patients (mean age 46.6 years; median age 45 years) with clinical suspicion of breast cancer recurrence were evaluated. For scintimammography all patients received a 740-900 MBq iv injection of (99)Tc(m)-MIBI; planar images were taken 5-10 min post-injection followed by supine single photon emission CT. Breast ultrasonography was performed in each patient using a 7.5 MHz transducer. Both MIBI uptake and ultrasound findings were documented using standard protocols. All patients had fine needle aspiration cytology biopsy (FNAC), core biopsy or excision biopsy for final tissue diagnosis. Of the 41 patients, 24 had true positive signs of local breast cancer recurrence upon ultrasonography, 10 were diagnosed as true negatives, a sensitivity of 86%, specificity 77%, positive predictive value (PPV) 89%, negative predictive value (NPV) 71% and accuracy 83% (p = 0.001). By comparison, scintimammography findings were found to be true positive in 25 patients and true negative in 12 patients - sensitivity 89%, specificity 92%, PPV 96%, NPV 80% and accuracy 90% (p = 0.001). Using a combination of these two modalities, the combined sensitivity was 100%, specificity 77%, PPV 90%, NPV 100% and accuracy 93%. The high NPV of the two studies in combination implies a potential use of this approach to exclude recurrent disease in patients with a low initial index of suspicion and/or when histology is indeterminate.     

Preoperative localization using a bidimensional mammographic technique of non-palpable lesions of the breast

It is widely known how the early diagnosis and treatment of breast cancer may lead to better prognosis. When a non-palpable breast lesion detected with mammography is correctly localized with fine-needle biopsy under X-ray guidance, the surgeon can easily remove the lesion while preserving normal breast tissue. In such cases, histology is also possible. The authors describe an easy bidimensional technique for the preoperative localization of occult nonpalpable breast lesions with a fine-needle. The procedure is feasible also with out-of-date equipment and does not cause any discomfort to the patients. It should be performed on all women with mammographic suspicion of non-palpable breast lesion. From January through December 1989 the authors performed 64 preoperative fine-needle biopsies of clinically-occult breast lesions. The presence of a lesion associated with microcalcifications was found to be indicative of malignancy more often than in the case of microcalcifications or lesions alone. Of 64 cases, histology demonstrated malignancy in 31 patients.     

Complementary use of scintimammography with 99m-Tc-MIBI to triple diagnostic procedure in palpable and non-palpable breast lesions

Purpose: 
The aim of this study was to determine the clinical value of scintimammography with ⁹⁹m-Tc-MIBI (Sc) as a complementary method to the triple diagnostic procedure in the diagnosis of breast lesions. Material and Methods: 
Ninety-six consecutive patients with 65 palpable and 54 non-palpable breast lesions were included in a prospective study. All lesions were evaluated by clinical examination, mammography and fine-needle-aspiration cytology (FNAC), called triple diagnostic procedure (TD). Prone planar scintimammography with ⁹⁹m-Tc-MIBI was performed in all patients. Five groups were defined for diagnosis: 1 = normal; 2 = benign; 3 = probably benign; 4 = highly suspect of malignancy; and 5 = malignant. In the calculations, groups 1-3 were considered benign, and 4-5 malignant. All lesions were excised and examined histologically. The additional value of Sc + TD procedure was studied separately for palpable and non-palpable lesions. Results: 
Histologically, 83 malignant and 36 benign lesions were found in the 119 breast lesions. Sensitivity for malignancy in palpable lesions of TD alone and of the combination TD + Sc were 95.6% and 100%, respectively. Sensitivity for malignancy in non-palpable lesions of TD and TD + Sc was 89.1% and 97.2%, respectively. Conclusion: 
Adding scintimammography to the triple diagnostic procedure increased the sensitivity for the detection of both palpable and non-palpable breast cancers, but decreased the specificity.     

Technetium-99m sestamibi scintimammography: the influence of histopathological characteristics, lesion size and the presence of carcinoma in situ in the detection of breast carcinoma.

The limit of detection of invasive carcinoma by scintimammography appears to be >10 mm, but not uncommonly smaller invasive carcinoma is detected in the presence of pre-invasive carcinoma (carcinoma in situ). The aims of this study were to determine whether a relationship exists between the presence of carcinoma in situ and the detection of invasive carcinoma using scintimammography, and to further characterise the influence of lesion size and histopathological characteristics on the diagnostic accuracy of scintimammography for the detection of invasive breast carcinoma. One hundred and seventeen patients were studied prospectively by scintimammography, X-ray mammography and, where appropriate, breast ultrasound prior to excision biopsy of all suspicious breast masses (n=123, 93% palpable). Thirty-five of these patients had a history of previous ipsilateral breast carcinoma. Sixteen percent of biopsy specimens were benign. The remaining specimens were malignant or pre-malignant. The overall diagnostic sensitivity of scintimammography was 84% and the specificity was 80%. The overall sensitivity and specificity for X-ray mammography (n=123), including those examinations combined with breast ultrasound (n=76), were 73% and 69%, respectively. The maximum size of the measured invasive carcinoma ranged from 5 to 80 mm (median 20 mm). Although the maximum size detected for invasive carcinoma in the presence of carcinoma in situ ranged from 3 to 40 mm (median 20 mm), this difference was not statistically significant (P=1.10, t test). Seven cases of carcinoma in situ were not detected by scintimammography. The diagnostic sensitivity of scintimammography for the detection of invasive carcinoma was 98% for lesions 16-25 mm, 91% for lesions 11-25 mm, 78% for lesions >25 mm and 55% for lesions <11 mm. Scintimammography may offer increased diagnostic accuracy for the detection of breast carcinoma, thereby complementing anatomical imaging. This is particularly evident in technically difficult patients who have had previously treated breast cancer. There appears to be no difference in the diagnostic sensitivity of scintimammography for the detection of invasive carcinoma in the presence or absence of carcinoma in situ.