Added value of semi-quantitative breast-specific gamma imaging in the work-up of suspicious breast lesions compared to mammography, ultrasound and 3-T MRI.

OBJECTIVE: To prospectively analyse the diagnostic value of semi-quantitative breast-specific gamma imaging (BSGI) in the work-up of suspicious breast lesions compared with that of mammography (MG), breast ultrasound and MRI of the breast. METHODS: Within a 15-month period, 67 patients with 92 breast lesions rated as Category IV or V according to the breast imaging reporting and data system detected with MG and/or ultrasound were included into the study. After the injection of 740-1110 MBq of Technetium-99m ((99m)Tc) SestaMIBI intravenously, scintigrams were obtained in two projections comparable to MG. The BSGI was analysed visually and semi-quantitatively by calculating a relative uptake factor (X). With the exception of two patients with cardiac pacemakers, all patients underwent 3-T breast MRI. Biopsy results were obtained as the reference standard in all patients. Sensitivity, specificity, positive- and negative-predictive values, accuracy and area under the curve were calculated for each modality. RESULTS: Among the 92 lesions, 67 (72.8%) were malignant. 60 of the 67 cancers of any size were detected by BSGI with an overall sensitivity of 90%, only exceeded by ultrasound with a sensitivity of 99%. The sensitivity of BSGI for lesions <1 cm declined significantly to 60%. Overall specificity of ultrasound was only 20%. Specificity, accuracy and positive-predictive value were the highest for BSGI (56%, 80% and 85%, respectively). X was significantly higher for malignant lesions (mean, 4.27) and differed significantly between ductal types (mean, 4.53) and the other histopathological entities (mean, 3.12). CONCLUSION: Semi-quantitative BSGI with calculation of the relative uptake factor (X) can help to characterize breast lesions. BSGI negativity may obviate the need for biopsy of breast lesions >1 cm with low or intermediate prevalence for malignancy. ADVANCES IN KNOWLEDGE: Compared with morphological imaging modalities, specificity, positive-predictive value for malignancy and accuracy were the highest for BSGI in our study. BSGI negativity may support the decision not to biopsy in selected lesions with a low or low-to-moderate pre-test probability for malignancy.

99mTc tetrofosmin myocardial perfusion scintigraphy in CAD. Performance with early and standard delayed acquisition and fractional flow reserve.

AIM: Early stress imaging (15 min after injection of the radiopharmaceutical) in 99mTc tetrofosmin myocardial perfusion scintigraphy (MPS) has been shown feasible in comparison to standard imaging after 45 minutes, but the effects on image quality and diagnostic accuracy ask for further evaluation. PATIENTS, METHODS: 97 patients (61 men, 36 women, age 69 ± 11 years) underwent both early (EA) and standard (SA) acquisition (after 14 ± 4 min and 43 ± 6 min, respectively) using 99mTc tetrofosmin gated SPECT with iterative reconstruction. Sub-diaphragmatic tracer activity and image quality was scored in a 4-point scale by blinded observers. Semiquantitative myocardial perfusion analysis was performed on a 17-segment model using standard cardiac quantification SPECT software (4 DM-SPECT). Stenoses of indeterminate haemodynamic significance were validated by measurement of fractional flow reserve (FFR). RESULTS: Extra-cardiac tracer activity was more commonly found in EA (43%) than in SA (38%), but without any diagnostic impact in > 95% of the patients. The mean summed stress score was significantly higher for early than standard imaging (6.4 ± 6.3 vs. 5.6 ± 6.1, p = 0.009). The amount of ischaemic area was not significantly different (EA: 9.1 ± 6.7 % vs. SA: 7.8 ± 6.9 %). The mean stress ejection fraction was 52 ± 11% (EA) compared to 55 ± 11 % (SA) (p = ns). FFR was inversely related to SDS at early (r = -0.704, p < 0.05) and standard (r = -0.678, p < 0.05) acquisition. All patients with a FFR < 0.8 (considered as hemodynamically significant stenoses) revealed a positive scan. CONCLUSION: Stress 99mTc tetrofosmin MPS with early acquisition is feasible and at least equally accurate when iterative reconstruction is applied.

Prolonged back pain attributed to suspected spondylodiscitis. The value of ¹8F-FDG PET/CT imaging in the diagnostic work-up of patients.

OBJECTIVE: This study aimed at investigating the diagnostic value of ¹8F-FDG PET/CT in cases of suspected spondylodiscitis after inconclusive results in initial diagnostic imaging. PATIENTS, METHODS: We analysed 38 consecutive cases of suspected spondylodiscitis (mean age: 67 ± 14 years) with chronic back pain referred to our Department during a four-year-period after inconclusive results in MRI or other conventional modalities. Clinical histories were retrospectively worked up and results of ¹8F-FDG PET/CT and MRI were analysed and related to the results of biopsy, blood culture and a one-year clinical follow-up. ¹8F-FDG PET/CT was analysed qualitatively by visual analysis and quantitatively. We measured the maximum standardized uptake value (SUV(max)) in the region of back pain and in a corresponding reference region (RR) in each patient and calculated a SUV(max-ratio). RESULTS: 22/38 patients had confirmed spondylodiscitis, while 16 were negative. ¹8F-FDG PET/CT established a correct diagnosis in 34 out of 38 patients by visual analysis. ¹8F-FDG PET/CT reached a sensitivity, specificity and accuracy of 81.8%, 100%, 89.5% and a PPV and NPV of 100% and 80%. MRI, performed in 27 patients reached a sensitivity, specificity and accuracy of 75%, 71.4%, 74.1% and a PPV and NPV of 88.2% and 50%. Patients with confirmed spondylodiscitis showed a significantly (p < 0.05) higher SUV(max) of 5.1 ± 1.9 and SUV(max)-ratio of 1.9 ± 0.8 than patients without it (SUV(max) (3.8 ± 1.5), SUV(max-ratio) (1.2 ± 0.3). CONCLUSION: ¹8F-FDG PET/CT provided diagnostic information in most patients with chronic back pain and suspected spondylodiscitis. It was helpful in establishing a correct diagnosis in challenging cases of spondylodiscitis with mostly unclear findings in previous MRI.

Lymphoscintigraphy in breast cancer patients after neoadjuvant chemotherapy. Diagnostic value and the work-up of sentinel node negative patients.

UNLABELLED: The AIM of this study was to evaluate the diagnostic value of lymphatic mapping by lymphoscintigraphy in breast cancer patients undergoing neoadjuvant chemotherapy (NCTX). We assessed the association between clinicopathological factors and nonvisualized sentinel nodes during preoperative lymphoscintigraphy. As secondary aims, we analyzed whether post NCTX axillary ultrasonography and fluorine-18 fluorodeoxyglucose positron emission tomography and computed tomography (F18-FDG-PET/CT) might be useful for staging in case of nonvisualized sentinel nodes. PATIENTS, METHODS: 61 patients with newly diagnosed, invasive breast cancer potentially eligible for NCTX were included in this substudy of a prospective trial on the monitoring of NCTX with ¹8F-FDG PET/CT. In all patients, lymphoscintigraphy was performed prior to sentinel lymph node biopsy (SLNB). 42 patients received neoadjuvant chemotherapy. 19 patients did not receive NCTX. After SLNB, mastectomy or lumpectomy (breast-conserving surgery) combined with level I and II axillary lymph node dissection were performed. Cases of nonvisualized sentinel nodes were analyzed with respect to tumour and patient characteristics and the results of ultrasonography and ¹8F-FDG-PET/CT before and after NCTX. RESULTS: Lymphoscintigram successfully identified at least one sN in 55 patients (i.e. identification rate of 90%). The risk of failure to identify the sN was associated statistically with a positive clinical nodal status prior to NCTX (p = 0.021). There was no statistical difference between patients with visualized and nonvisualized sN with respect to age, tumour grade, tumour size, pathological lymph node status or tumour histology. In patients without NCTX the sN identification rate was 100% versus 86% in patients with NCTX (n.s.). The FNR of patients with NCTX was 9.1%. Post NCTX axillary ultrasonography or FDG-PET/CT did not provide accurate information about the lymph node status in case of failing lymphatic mapping. CONCLUSION: On the basis of our findings, SLNB can not yet be recommended as a reliable staging method in breast cancer patients undergoing neoadjuvant chemotherapy. Patients with clinically positive axillary lymph nodes have a higher chance of unsuccessful lymphatic mapping by lymphoscintigraphy. Performing SLNB before NCTX in clinically node-negative patients may identify the subset of patients in whom axillary lymph node dissection can be omitted. Post NCTX axillary ultrasonography and ¹8F-FDG-PET/CT can not be suggested as valid axillary staging methods in case of a failed lymphatic mapping.

Reproducibility of lymphoscintigraphy in cutaneous melanoma: can we accurately detect the sentinel lymph node by expanding the tracer injection distance from the tumor site?

UNLABELLED: The aim of the study was to determine whether the sentinel lymph node (SLN) can be accurately detected in cutaneous melanoma patients when the injection distance from the tumor site is expanded. METHODS: In 100 patients with cutaneous melanoma, lymphoscintigraphy was performed twice. First, we injected 37 MBq (99m)Tc nanocolloid intracutaneously at a 2- to 5-mm distance from either the melanoma or the biopsy scar. The injection was followed by dynamic imaging, which continued until the SLN became visible. On another day, we repeated the investigation, injecting the radiopharmaceutical intracutaneously exactly 10 mm from the previous injection site. The detected SLNs of both investigations were compared to determine the number and location of SLNs for each patient. RESULTS: The SLN identification rate was 94% with close injection and 100% with 10-mm-distant injection. All SLNs detected with close injection were visible with distant injection. In 84 of 100 patients, the images of both investigations showed the same number and location of SLNs. In the remaining 16 patients, an additional SLN was detected with the distant injection. CONCLUSION: The reproducibility of lymphoscintigraphy using different injection distances was 84%. The discordance in the remaining 16% was caused by detection of a lymph node in addition to the original SLN with distant injection. Diagnostic excision of the primary tumor before lymphoscintigraphy was possible without preventing detection of the original SLN. However, in 16% of our patients, excision of an additional lymph node had to be considered when lymphoscintigraphy was performed after diagnostic excision.

Lymphoscintigraphy in breast cancer patients--comparison of peritumoural and intradermal injection.

UNLABELLED: AIM of this study was to determine whether the sentinel lymph nodes (SLNs) can be accurately identified in breast cancer patients with intradermal injection of the radiotracer above the primary tumour in comparison to peritumoural injection. METHODS: In 45 women with breast cancer we performed lymphoscintigraphy on two separate days. We injected Tc-99m nanocolloid on the first day peritumourally, and on a separate day intradermally. The results of both investigations using different injection sites were compared in order to determine the number and location of SLNs. RESULTS: The SLN identification rate using peritumoural injection was 71% (32 of 45 patients) and 96% (43 out of 45 patients) using intradermal injection. In 62% (28 of 45 patients) the number and location of the SLNs were identical. In 97% (31 of 32 patients) in whom a SLN was detected using peritumoural injection, the same SLNs reappeared with intradermal injection. There were no false negative findings with the peritumoural administration of tracer whereas the intradermal administration approach resulted in a false negative rate of 13%. CONCLUSION: In women with breast cancer the reproducibility of lymphoscintigraphy using peritumoural and intradermal injection sites was 62%. The intradermal injection modality enables the detection of a SLN in patients where the peritumoural injection failed but it has the disadvantage of a higher false negative rate in comparison to the peritumoural injection technique.

Whole-body scintigraphy in melanoma patients: comparison of 99Tcm-tetrofosmin and 201Tl.

The aim of this study was to determine the diagnostic value of 99Tcm-tetrofosmin whole-body imaging in comparison to 201Tl scintigraphy in patients with metastatic melanoma. In 27 patients with known or suspected melanoma metastases we performed 201Tl scintigraphy and 99Tcm-tetrofosmin scintigraphy using a 1-day protocol. In five patients with known locoregional metastasis the in vivo uptake kinetics of both radiotracers were compared. The final diagnosis was confirmed by surgical histology in 39 lesions (group I) and computed tomography (CT) and clinical course in 14 lesions (group II). In group I, containing mainly locoregional metastases, 201Tl scintigraphy correctly identified 36 of 39 metastases and 99Tcm-tetrofosmin 35 of 39 resulting in a sensitivity of 92% and 90% respectively. The T/B ratios of 201Tl (1.4-4.0, mean 2.15) were statistically significantly higher in comparison to tetrofosmin (1.3-3.0, mean 1.88). However, both radiotracers showed similar uptake and washout kinetics with a maximum of tracer uptake between 1 and 5 min p.i. In group II, containing mainly cerebral and pulmonary metastases, both methods correctly identified six of 14 metastases resulting in a sensitivity of only 43%. We conclude that the uptake of 99Tcm-tetrofosmin and 201Tl in melanoma metastases is very similar. The T/B ratios with 99Tcm-tetrofosmin are significantly lower than with 201Tl. In locoregional melanoma metastases the sensitivity of tetrofosmin scintigraphy is identical with 201Tl imaging and amounts to 90%. In cerebral and lung metastases the sensitivity of both methods is limited when using whole-body scintigraphy.

[Radius fractures in typical sites in young patients--is it early osteoporosis?]. / Radiusfrakturen an typischer Stelle bei jungen Patientinnen--ist das frühe Osteoporose?

Fractures of the radius in premenopausal women caused by a slow speed trauma are often associated with osteoporosis. Out of 156 patients we were able to screen 26 for osteoporosis. Bone mineral density (BMD) of the lumbar spine and the femoral neck was compared with the age related control group. At the lumbar spine the mean decrease of BMD was 13.1% (CI 95% 8.78 to 17.4%; SEM = 2.1). The patients showed a BMD between Z = -1 and Z = -2 and 4 patients lessen than Z = -2. At the femoral neck the mean decrease of BMD was 15.8% (CI 95% 11.3 to 20.3%; SEM = 2.17). Z was between -1 and -2 in 10 patients and smaller -2 in 6 patients. There was no correlation between the number of risk factors and bone mineral decrease. All evaluated laboratory tests were within normal range. As a result of our investigation we suggest looking for osteoporosis in premenopausal women with fractures following slow speed trauma as a routine procedure to offer adequate therapy.