Comparison of planar and SPECT scintimammography with 99mTc-sestamibi in the diagnosis of breast carcinoma

PURPOSE: To compare results of planar and SPECT breast imaging with 99mTc-MIBI in detecting primary breast cancer. MATERIAL AND METHODS: Twenty-six consecutive patients with 34 suspected breast lesions underwent both planar and SPECT scintimammography. Ten minutes after injection of 700 MBq 99mTc-MIBI, 2 prone lateral projections were obtained, followed by a supine anterior projection. Forty minutes after injection, a SPECT study was done. All lesions were operated upon and verified with histopathology. RESULTS: A sensitivity of 85% and specificity of 88% of planar scintimammography in diagnosis of primary breast lesions were achieved. The corresponding values for SPECT were 61% and 64%. CONCLUSION: The diagnostic accuracy of planar scintimammography was not improved by using SPECT imaging.     

^99mTc-MIBI与^99mTc-Octreotide生长抑素受体显像诊断乳腺癌的对比研究

目的:比较99mTcMIBI与99mTcOctreotide生长抑素受体显像对乳腺癌诊断的临床价值。材料和方法:对36例怀疑为乳腺癌的患者术前行99mTcMIBI显像,48小时后行99mTcOctreotide生长抑素受体显像,以术后病理检查结果作为金标准。结果:36例中,25例为乳腺癌,其中11例发生腋窝淋巴结转移;11例患者为乳腺良性病变。两种显像方法对乳腺癌诊断的灵敏度、特异性、准确性分别为92.0%、63.6%、83.3%和92.0%、27.3%、72.2%。结论:99mTcMIBI显像与99mTcOctreotide生长抑素受体显像对乳腺癌均有较好的诊断价值,但99mTcOctreotide生长抑素受体显像诊断特异性较低。由于本研究的病例数有限,有待于进一步的工作深入探讨。     

Evaluation of planar scintimammography with 99mTc-MIBI in the detection of axillary lymph node metastases of breast carcinoma.

PURPOSE: The aim of our prospective study was to evaluate the role of planar scintimammography with 99mTc-MIBI in detecting axillary lymph node metastases in women with primary breast carcinoma. MATERIAL AND METHODS: Fifty-eight patients underwent scintimammography rior to axillary lymph node dissection. Ten minutes after injection of 700 MBq 99mTc-MIBI, two prone lateral projections were obtained, followed by a supine anterior projection. Sixty-one axillae (3 bilateral) were operated upon and the status of the lymph nodes verified with histopathology. The scintigraphic result was compared to the histopathologic findings. RESULTS: A sensitivity of 67% and a specificity of 80% of planar scintimammography in detecting axillary lymph node metastases were achieved. CONCLUSION: Scintimammography with 99mTc-MIBI is not recommended as a routine method for the detection of axillary lymph node metastases in patients with breast carcinoma.     

Evaluation of ocular tumors with technetium-99m-MIBI: planar pinhole technique or SPECT?

OBJECTIVE: This study compares 2 imaging protocols, planar pinhole technique (PPHT) and SPECT, for evaluating ocular masses with 99mTc-MIBI. METHODS: Sixteen patients with ocular lesions were studied. Planar images were acquired 10 min after the injection of 740 MBq 99mTc-MIBI with an LFOV camera fitted with a pinhole collimator (5.0 mm). A SPECT study was performed immediately after the planar study, using a 360 degrees orbit, 64 steps, 20 s/stop, a 128 x 128 matrix, and a low-energy high-resolution (LEHR) collimator. Twelve lesions (9.5-18.0 mm) proved to be malignant: 8 primary tumors (ocular melanoma); 3 local relapses of different tumors of the conjunctiva; and 1 ocular metastasis from breast cancer. The remaining 4 lesions (10.0-16.0 mm) were benign: 1 inflammatory lesion; 1 benign intraocular calcification; and 2 naevi. RESULTS: SPECT images showed 11 of 12 malignant lesions (91.6%), whereas the planar technique demonstrated only 4 of the 12 lesions (33.3%). One false-positive result, the inflammatory lesion, was visualized by both techniques. The remaining benign lesions were not detected with either method. CONCLUSION: Technetium-99m-MIBI SPECT is a sensitive technique for detecting malignant ocular tumors. SPECT imaging is a better alternative to planar imaging for ocular tumors.     

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.     

Comparative evaluation of 99mTc-MIBI and 99mTc-HMDP scintimammography for the diagnosis of breast cancer and its axillary metastases

The purpose of the present study was to compare scintimammography using technetium-99m hexakis 2-methoxyisobutylisonitrile (MIBI) with that using 99mTc-hydroxymethylene diphosphonate (HMDP) in the detection of breast cancer and its axillary lesions. The study population comprised 50 consecutive females with breast cancer who were scheduled for surgery. All patients underwent scintimammography with 99mTc-MIBI and 99mTc-HMDP. The images were acquired 5 min (early) and 2 h (delayed) after injection of each radiopharmaceutical. Regions of interest were placed over the breast tumour (T), the axillary lesion (A) and the normal ipsilateral breast tissue (N). The two count ratios were calculated, i.e. the tumour to normal breast tissue ratio (T/N) and the axillary lymph node to normal breast tissue ratio (A/N). For the breast tumours, using 99mTc-MIBI the positive rate was 86% (43/50) for the early and 72% (36/50) for the delayed images. The corresponding values using 99mTc-HMDP were 72% (36/50) and 40% (20/50), respectively. Histopathological examination revealed metastatic lymph node involvement in 22 patients. For the axillary lesions, using 99mTc-MIBI the positive rate was 72.7% (16/22) for the early and 54.5% (12/22) for the delayed images. Using 99mTc-HMDP, the positive rate was only 18.2% (4/22) for the early and 4.5% (1/22) for the delayed images. Using 99mTc-MIBI, the mean T/N (+/- SD) ratios on early and delayed images were 2.69 +/- 1.64 and 2.03 +/- 1.16, respectively, and the mean A/N (+/- SD) ratios on early and delayed images were 2.20 +/- 1.23 and 1.80 +/- 1.20, respectively. The corresponding values using 99mTc-HMDP were 1.77 +/- 0.91, 1.42 +/- 0.72, 1.27 +/- 0.63 and 1.08 +/- 0.25, respectively. The T/N and A/N ratios on the early and delayed 99mTc-MIBI images were both significantly higher than those obtained using 99mTc-HMDP. 99mTc-MIBI scintimammography is more sensitive than 99mTc-HMDP scintimammography for the detection of breast cancer and its axillary lymph node metastases.     

~（99m）Tc-MIBI显像对甲状腺“冷（凉）结节”良、恶性鉴别的临床价值

目的探讨99mTc-MIBI显像对甲状腺冷（凉）结节良、恶性鉴别的临床价值。方法 75例99mTcO4-甲状腺显像为＂凉（冷）结节＂患者,均行99mTc-MIBI显像,其显像结果与术后病理结果相对照。结果 75例患者中,99mTc-MIBI显像呈阳性者32例,其中经病理诊断18例为恶性肿瘤,14例为良性病变;99mTc-MIBI显像呈阴性者43例,经病理诊断后40例为良性病变,3例为恶性肿瘤。本组99mTc-MIBI显像的诊断灵敏度为85.71%,特异性为74.07%,准确性为77.33%。结论 99mTc-MIBI核素显像对甲状腺结节良、恶性鉴别诊断的特异性低,单独应用受限,但可作为其他诊断方式非常重要的辅助手段。     

The role of scintimammography with 99mTc-sestamibi as a complementary diagnostic technique in the detection of breast cancer

Purpose: To prospectively determine the clinical value of scintimammography (Sc) with ^99mTc-sestamibi as a complementary method to triple diagnosis (TD) in detecting malignant disease of the breast.Material and Methods: Ninety-six patients with 119 clinically or mammographically detected breast lesions underwent TD procedures, including clinical examination, mammography and fine-needle aspiration cytology. Prone planar Sc with ^99mTc-sestamibi was performed in all 96 patients. Five groups were defined for diagnosis: 1=normal; 2=benign; 3=probably benign; 4=highly suspect of malignancy; and 5=malignant. All lesions were histopathologically examined. The results of each method per se and the combination of TD with Sc (TD+Sc) were analyzed.Results: Histopathology of the 119 surgically excised breast lesions found 83 malignant and 36 benign lesions. TD missed 6 of 83 carcinomas, resulting in a sensitivity of 92.7%. Sc alone showed sensitivity of 85.5%. The combination TD+Sc missed 1 of 83 carcinomas, and thus had a sensitivity of 98.7%. In mammographically dense breasts both TD and Sc detected 16 of 18 carcinomas, while the combination TD+Sc led to detection of all 18 carcinomas.Conclusion: Adding Sc to TD increases the sensitivity for detection of breast carcinomas. Sc with ^99mTc-sestamibi is recommended as a complimentary method to TD in selected cases such as mammographically dense breasts.     

Mammotomography with pinhole incomplete circular orbit SPECT.

Dedicated mammotomography with pinhole incomplete circular orbit (PICO) SPECT imaging of an uncompressed pendant breast was evaluated with small, very-high-stopping-power pinhole apertures. Comparisons were made with planar pinhole scintimammography. Enhanced 3-dimensional imaging performance with very-high-stopping-power apertures is thought to ultimately yield improved sensitivities for lesion detection and identification in breast disease. METHODS: Pinhole collimators made of high-density and high atomic number (184)W or depleted (238)U, with aperture diameters from 1 to 4 mm, were used to image 0.6- and 1.0-cm-diameter spherical lesions in a pendulous, uncompressed breast phantom in planar and PICO-SPECT modes. The breast was centered on the horizontal axis of rotation of an incomplete circular orbit. Lesion, breast and body, and myocardial activities (L:B:M) were included in the phantoms to simulate clinical imaging conditions with (99m)Tc (140 keV). Lesion contrasts and signal-to-noise ratios (SNRs) for all apertures were determined for near clinical acquisition times for L:B:M ratios of 12:1:20 and 7:1:25. A set of minidisks inserted in the breast phantom was scanned to determine sampling limitations at depth from the nipple. In an initial study, a patient with biopsy-confirmed breast carcinoma was injected with 960 MBq (99m)Tc-tetrofosmin and scanned 2 h later with planar pinhole and PICO-SPECT techniques. RESULTS: Overall, for PICO-SPECT imaging there were small differences in measured counting rate sensitivity (4.9%) and lesion contrast (8.8%) with larger SNR differences (20.8%) between tungsten and depleted uranium pinhole materials at this energy and these lesion sizes. Backgrounds from simulated myocardial uptake had minor contributions in all reconstructed image volumes because of the rapid sensitivity fall-off for pinhole apertures. An optimal aperture diameter between 2 and 3 mm was determined from peak SNR, indicating that these aperture sizes may have the best performance for lesions as small as 0.6 cm in diameter with activity concentration ratios of (99m)Tc similar to those currently seen in patients. Both lesions were visualized with PICO-SPECT better than with planar pinhole imaging, with respective contrast improvements >20 times the values obtained from planar imaging for the same pinholes. In the patient study, higher contrast (>6) visualization of the active tumor periphery was obtained with PICO-SPECT than with planar imaging. CONCLUSION: These results indicate that the enhanced spatial resolution of smaller apertures outweighs the loss in sensitivity in small lesion identification with PICO-SPECT. Although the imaging differences between investigated aperture types are small and some limitations to this imaging approach exist, dedicated PICO-SPECT of the breast appears to be an improved technique compared with conventional planar pinhole scintimammography. This technique provides enhanced contrast and SNR for imaging small lesions with the high-resolution pinhole apertures along with 3-dimensional localization of the lesions.     

(99)mTc-tetrofosmin SPET in the detection of both primary breast cancer and axillary lymph node metastasis.

The aim of this study was to evaluate the usefulness of (99m)Tc-tetrofosmin single-photon emission tomography (SPET) in the detection of both primary breast cancer and axillary lymph node metastasis. We studied 192 consecutive patients in whom primary breast cancer was suspected on the basis of mammography and/or physical examination. After intravenous injection of 740 MBq (99m)Tc-tetrofosmin, both planar and SPET scintimammography was performed in all patients using a rectangular dual-head gamma camera equipped with low-energy, high-resolution, parallel-hole collimators. In 175 patients with breast cancer at histology, the per-lesion overall sensitivity of SPET and planar imaging for the detection of breast cancer was 95.8% and 75.9% (P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 96.5% and 79.5% in palpable (P<0.0005) and 90% and 45% in non-palpable lesions (P<0.01). With regard to lesion size, the sensitivity of SPET and planar imaging was, respectively, 90.5% and 45.2% in lesions < or =10 mm ( P<0.0005), 95.3% and 81.4% in lesions of 11-20 mm (P<0.005), 100% and 84.6% in lesions of 21-30 mm (P<0.05) and 100% and 95.8% in lesions >30 mm (P>0.05). In the remaining 17 patients with benign mammary lesions at histology, per-lesion overall specificity of SPET and planar imaging was 76.2% and 85.7% (P>0.05), respectively. Neither SPET nor planar imaging showed false-positive results in non-palpable lesions or in those < or =10 mm. In 173 breast cancer patients submitted to axillary lymph node dissection (ALND), per-axilla overall sensitivity of SPET and planar imaging in the detection of axillary lymph node metastasis was 93% and 52.3% ( P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 100% and 82.6% in palpable nodes (P>0.05), 90.5% and 41.3% in non-palpable nodes (P<0.0005), 92.8% and 35.7% in the presence of < or =3 nodes ( P<0.0005) and 93.2% and 68.2% in the presence of >3 nodes (P<0.005). The specificity of SPET and planar imaging was 91% and 100% (P<0.05), respectively. (99m)Tc-tetrofosmin SPET appears to be a reliable method for the detection of both primary BC and axillary lymph node metastasis, and its diagnostic accuracy exceeds that of (99m)Tc-tetrofosmin planar scintimammography. The use of SPET is particularly important in the identification of small non-palpable primary carcinomas and metastatic axillae with < or =3 non-palpable lymph nodes. More extensive use of SPET appears warranted in the management of breast cancer patients.     

Use of 99mTc-furifosmin scintigraphy--planar and SPECT--to evaluate suggestive palpable and nonpalpable breast lesions.

Our objective was to evaluate the role of 99mTc-furifosmin scintigraphy--planar and SPECT--in discriminating benign from malignant breast disease. METHODS: The trial was prospective, open, and diagnostic. We recruited 30 consecutive patients with 14 palpable and 16 nonpalpable breast lesions. After receiving informed consent, we injected 555-640 MBq 99mTc-furifosmin intravenously in the arm contralateral to the breast lesion. Planar imaging and SPECT were performed. All patients underwent excision of the tumor within 2 wk. Using histology as the gold standard, we calculated sensitivity, specificity, and positive and negative predictive values for 99mTc-furifosmin in planar and SPECT technique. RESULTS: For 18 malignant and 12 benign breast lesions, a sensitivity of 50% for planar imaging and 72% for SPECT was seen. Specificity and positive and negative predictive values were 83%, 82%, and 53%, respectively, for planar imaging and 50%, 68%, and 55%, respectively, for SPECT. For the 14 palpable tumors (10 malignant, 4 benign), which averaged 17+/-10 mm in size (size range, 4-45 mm), a sensitivity of 60% for planar imaging and 80% for SPECT was achieved. Sixteen lesions were not palpable (median size, 9+/-3 mm [size range, 4-13 mm]). In this subgroup, 99mTc-furifosmin scintigraphy yielded a sensitivity of 37% for planar and 62% for SPECT technique (P>0.05). CONCLUSION: 99mTc-furifosmin scintigraphy is not a potent competitor to established scintigraphic procedures. In comparing this tracer with 99mTc-sestamibi and 99mTc-tetrofosmin, we cannot recommend 99mTc-furifosmin for the diagnosis of breast cancer.     

99mTc-tetrofosmin SPET in the detection of both primary breast cancer and axillary lymph node metastasis

The aim of this study was to evaluate the usefulness of ^99mTc-tetrofosmin single-photon emission tomography (SPET) in the detection of both primary breast cancer and axillary lymph node metastasis. We studied 192 consecutive patients in whom primary breast cancer was suspected on the basis of mammography and/or physical examination. After intravenous injection of 740 MBq ^99mTc-tetrofosmin, both planar and SPET scintimammography was performed in all patients using a rectangular dual-head gamma camera equipped with low-energy, high-resolution, parallel-hole collimators. In 175 patients with breast cancer at histology, the per-lesion overall sensitivity of SPET and planar imaging for the detection of breast cancer was 95.8% and 75.9% (P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 96.5% and 79.5% in palpable (P<0.0005) and 90% and 45% in non-palpable lesions (P<0.01). With regard to lesion size, the sensitivity of SPET and planar imaging was, respectively, 90.5% and 45.2% in lesions ⢪ mm (P<0.0005), 95.3% and 81.4% in lesions of 11-20 mm (P<0.005), 100% and 84.6% in lesions of 21-30 mm (P<0.05) and 100% and 95.8% in lesions >30 mm (P>0.05). In the remaining 17 patients with benign mammary lesions at histology, per-lesion overall specificity of SPET and planar imaging was 76.2% and 85.7% (P>0.05), respectively. Neither SPET nor planar imaging showed false-positive results in non-palpable lesions or in those ⢪ mm. In 173 breast cancer patients submitted to axillary lymph node dissection (ALND), per-axilla overall sensitivity of SPET and planar imaging in the detection of axillary lymph node metastasis was 93% and 52.3% (P<0.0005), respectively. The sensitivity of SPET and planar imaging was, respectively, 100% and 82.6% in palpable nodes (P>0.05), 90.5% and 41.3% in non-palpable nodes (P<0.0005), 92.8% and 35.7% in the presence of Г nodes (P<0.0005) and 93.2% and 68.2% in the presence of >3 nodes (P<0.005). The specificity of SPET and planar imaging was 91% and 100% (P<0.05), respectively. ^99mTc-tetrofosmin SPET appears to be a reliable method for the detection of both primary BC and axillary lymph node metastasis, and its diagnostic accuracy exceeds that of ^99mTc-tetrofosmin planar scintimammography. The use of SPET is particularly important in the identification of small non-palpable primary carcinomas and metastatic axillae with Г non-palpable lymph nodes. More extensive use of SPET appears warranted in the management of breast cancer patients.     

The comparison of dual phase Tc-99m MIBI and Tc-99m MDP scintimammography in the evaluation of breast masses: Preliminary report

The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.     

A head-to-head comparison between technetium-99m-tetrofosmin and technetium-99m-MIBI scintigraphy to evaluate suspicious breast lesions

The aim of this study was to assess the diagnostic value of technetium-99m-tetrofosmin and technetium-99m-MIBI in a head-to-head comparison. Both radiopharmaceuticals are routinely used for detecting breast cancer. In a prospective, open, diagnostic trial, the two radiopharmaceuticals were administered randomly on different days to the same 101 women suffering from 103 breast tumours. Planar images and single photon emission computer tomography (SPET) were performed. After histological examination of the tumours, sensitivity, specificity and positive and negative predictive value were compared. 99mTc-tetrofosmin and 99mTc-MIBI showed low sensitivity in planar images (44% vs 46%, respectively). SPET improved sensitivity (70% vs 69%, respectively). Specificity in planar images was 83% and 87%, and it was even lower using SPET (70% vs 78%, respectively). Positive predictive value in planar images was 76% vs 81%, and it was not changed by SPET. Negative predictive value was low in planar images (54% vs 57%, respectively), but it was improved by using SPET (65% vs 67%, respectively). In conclusion, 99mTc-tetrofosmin and 99mTc-MIBI scintigraphy show similar diagnostic value in assessing suspicious breast lesions.     

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     

The role of (99m)Tc-tetrofosmin pinhole-SPECT in breast cancer non palpable axillary lymph node metastases detection.

AIM: We evaluated the usefulness of (99m)Tc-tetrofosmin axillary pinhole (P)-SPECT in breast cancer (BC) non palpable axillary lymph node metastasis detection compared with conventional planar and SPECT scintimammography. METHODS: We studied prospectively 188 consecutive patients with suspected primary BC, negative at axillary clinical examination. Ten minutes after 740 MBq (99m)Tc-tetrofosmin injection, planar and SPECT scintimammography were acquired, followed by axillary P-SPECT imaging. RESULTS: At histology, 12 patients had benign mammary lesions and 176 had BC. Axillary lymph node dissection (ALND) was performed in all BC patients, bilaterally in 3 cases: 74/179 axillae had metastases. P-SPECT showed a significantly higher overall sensitivity than SPECT and planar (93.2% vs 85.1% and 36.5%, respectively; p<0.05 and p<0.0005, respectively) and was false negative in 5 patients with 1 metastatic node each, micrometastatic in 4/5 cases; SPECT and planar were also false negative in these 5 cases and in 6 and in 42 further cases, respectively. P-SPECT added important prognostic information by distinguishing single from multiple and pound 3 from >3 nodes; only P-SPECT defined the exact number of nodes in 15/25 patients with 2-4 nodes. P-SPECT showed the highest accuracy and NPV: 92.7% and 95%, respectively (SPECT 90.5% and 90%, respectively; planar 73.2% and 68.9%, respectively). CONCLUSION: (99m)Tc-tetrofosmin axillary P-SPECT appears highly accurate in BC non palpable axillary lymph node metastasis detection and significantly more sensitive than both planar and SPECT, its few false negative results predominantly concerning micrometastases; moreover, only P-SPECT gave additional important prognostic information. Given its very high NPV, P-SPECT could also be used to better select patients who might avoid ALND.     

Uptake and washout of 99mTcV-dimercaptosuccinic acid and 99mTc-sestamibi in the assessment of histological type and grade in breast cancer

This study was performed to investigate the relationship between histological type and grade, with the uptake and washout of 99mTc-hexakis-2-methoxyisobutylisonitrile (99mTc-sestamibi, 99mTc-MIBI) and 99mTcV-dimercaptosuccinic acid (99mTcV-DMSA) in breast cancer. Forty-five patients with histologically proven breast cancer had previously been referred for 99mTcV-DMSA and/or 99mTc-MIBI scintimammography. Twenty-five of them underwent both 99mTcV-DMSA and 99mTc-MIBI scintigraphy in a double phase study. Lateral prone and anterior supine images were acquired at 15 and 60 min after administration of 740-925 MBq of each radiotracer. Uptake ratios and retention index were calculated and correlated with histology and grade of malignancy. Histology showed eight different histotypes: 77.7% were infiltrating ductal or lobular carcinomas. Mammography was definitely positive in 32/45, indeterminate in 10 and negative in three cases (sensitivity 71%). 99mTcV-DMSA was true positive in 37/40 (sensitivity 92.5%) and 99mTc-MIBI in 28/30 (sensitivity 93.3%) breast cancers. Uptake ratios were significantly higher in ductal than in lobular carcinomas on 99mTcV-DMSA and 99mTc-MIBI scintigrams at early and delayed phases. Grade II carcinomas had significantly lower values of retention index (rapid washout) than grade III carcinomas. This finding was statistically significant only on 99mTc-MIBI scans and was observed in ductal and lobular carcinomas. The retention index did not show any significant difference between ductal and lobular carcinomas. Uptake ratios were also not statistically different between grade II and III cancers. It is concluded that 99mTc-MIBI and 99mTcV-DMSA uptake in breast cancer is probably related to histological type and may distinguish ductal from lobular carcinomas. To a certain degree, the washout rate may reflect the histological grade, but since grade is not the only factor influencing this phenomenon it should be explored further in conjunction with other parameters by multivariate analysis in order to clarify eventual indirect correlations.     

Application of technetium-99m-sestamibi in differentiation of active from inactive pulmonary tuberculosis using a single photon emission computed tomography method

OBJECTIVE: We studied the usefulness of 99mTc-methoxyisobutylisonitrile (MIBI) scintigraphy for differentiation between active and inactive pulmonary tuberculosis. METHODS: Thirty-six patients (aged 27-82 years, 16 males and 20 females) were included in our study. Each patient was injected with 740 MBq (20 mCi) 99mTc-MIBI and both planar and single photon emission computed tomography (SPECT) imaging were performed 15 and 60 min after injection. Twenty-four patients had active pulmonary tuberculosis (proven by sputum culture), and the remainder 12 had negative sputum culture. Semiquantitative as well as visual assessments were done on all sets of images. RESULTS: All of the 12 patients in the control group had negative scintigraphy on both planar and SPECT images. Twenty patients with active pulmonary tuberculosis had positive 99mTc-MIBI scintigraphy on planar images (sensitivity of 87.5%). SPECT images were positive in 23 patients with active pulmonary tuberculosis (sensitivity of 95.8%). Both semiquantitative and visual assessment of planar and SPECT images showed statistically significant differences between active and inactive pulmonary tuberculosis patients (P<0.001). Comparison of 15 and 60 min image sets did not show any statistically significant difference (P=0.956 and 0.457 for planar and SPECT images, respectively). CONCLUSION: 99mTc-MIBI has significant uptake in the active tuberculosis lesions and can be used to differentiate between active and inactive tuberculosis. The SPECT method is especially useful because of its higher sensitivity.     

99 Tcm-MIBI乳腺显像诊断乳腺癌评判方法的探讨

目的：探讨^99Tc^m-甲氧基异丁基异腈（MIBI）显像诊断乳腺癌的评判方法。方法：对100例乳腺肿瘤患者行^99Tc^m-MIBI平面显像,分别计算肿瘤与健侧对应部位（T／N）、肿瘤与胸骨（T／S）、肿瘤与心脏（T／H）的放射性比值,比较三者诊断乳腺癌的价值,确定最佳临界点,观察不同时相显像诊断乳腺癌的差异。结果：T／N检测乳腺癌的灵敏度、特异性和准确性最好,分别为84％、90％和87％;T／H分别为70％（P＞0．05）、72％（P＜0．05）、71％（P＜0．01）;T／S分别为58％（P＜0．01）、78％（P＞0．05）和68％（P＜0．01）。T／N比值在1．1－1．2间诊断乳腺癌的准确性最高。10或30min显像诊断乳腺癌结果无差异。结论：^99Tc^m-MIBI乳腺显像诊断乳腺癌较合适的评判方法为：选择T／N为判断指标,比值取1．1－1．2,显像时间为10或30min均可。     

^99mTc—MIBI提前显像在心肌梗塞诊断中的应用

目的：探讨99mTc-MIBI心肌显像能否成为急性心肌梗塞的快速诊断手段。资料和方法：选择临床确诊的心肌梗塞患者35例，于注射99mTc－MIBI后10min与60min以相同条件分别进行SPECT显像，并以相同条件分析处理图像，记录心肝肺的放射性计数率，比较两次显像结果的差异。结果；10min像阳性率31.2％，60min像为308％，符合率95.2％。有22个节段（4．8％）两次显像缺损程度有差异，以下后壁居多（13／22.59.1％）。图像质量以60min像为佳，心脏计数率随时间延长而降低，而心肝比、心肺比升高。结论：10min显像与60min显像在本组病例中具有很好的诊断一致性，至少可为急性心梗提前50min提供诊断，可望成为急性心梗的一种快速诊断手段。