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.

The impact of PET and PET/CT on treatment planning and prognosis of patients with NSCLC treated with radiation therapy.

AIM: 18F fluoro-deoxy-glucose (FDG) positron emission tomography (PET)-imaging improves the diagnostic accuracy in staging non small cell lung cancer (NSCLC) with possible impact on survival. This prospective study aimed to investigate the impact of PET and PET/CT on treatment planning and prognosis in patients with NSCLC treated with radiation therapy. METHODS: From October 2003 to January 2008, 91 consecutive patients with proven NSCLC stage T1-4N0-3M0 (clinical stages: I-IIIb) underwent accelerated, twice daily radiation therapy in target splitting technique. 70 patients received chemotherapy before radiation therapy (76%). All patients underwent PET or PET/CT-imaging and were followed up for a median time of 30 months. Imaging findings were interpreted visually and a SUV cut-off of 2.5 was applied for delineation of tumor borders. Changes in staging and planning treatment volumes (PTV) due to PET or PET/CT-imaging and survival were defined as primary study endpoints. The impact of tumor-type, stage, age, gender, weight loss and FDG-uptake in PET imaging as measured by the standardized uptake value (SUV) on survival were analysed as secondary endpoints. RESULTS: PET imaging provided additional diagnostic information over CT alone in 20% (N.=18) of our study population, leading to upstaging in 17% of them, respectively. In 5 patients (5.5% of 91) atelectasis could be separated from tumor tissue, PTV was altered in 9% (N.=8). 39 patients (43%) died during the observation period, mean overall survival was 32.3 months (95% Confidence intervalI 27.6-37.1) and tumor specific survival was 36.9 months (95 % CI 32.0-42.0), respectively. One- and two year survival rates reached 90.1% and 67.7%, respectively. Multivariate analysis did not reveal any significant prognostic impact of tumor-type, stage, age, gender or FDG-uptake as given by SUVmax (mean 13.6±6.8) or SUVmean (mean 5.5±1.6). CONCLUSION: The use of FDG-PET- and PET/CT-imaging provided incremental information relevant for treatment-planning in about 10 % of patients with NSCLC undergoing accelerated radiation therapy with curative intent. This prospective trial did not provide evidence for the assumption that the SUV might be an independent predictor of outcome.

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.

200 Sentinel lymph node biopsies without axillary lymph node dissection -- no axillary recurrences after a 3-year follow-up.

The aim of this study is to evaluate the rate of axillary recurrences in sentinel lymph node (SLN)-negative breast cancer patients after sentinel lymph node biopsy (SLNB) alone without further axillary lymph node dissection (ALND). Between May 1999 and February 2002, 333 consecutive patients with primary invasive breast cancer up to 4 cm and clinically negative axillae were entered into this prospective study. Sentinel lymph nodes were identified using the combined method with blue dye (Patent blue V) and technetium 99m-labelled albumin (Nanocoll). Sentinel lymph nodes were examined by frozen sections, standard haematoxylin and eosin staining and immunohistochemistry staining. In SLN-positive patients, ALND was performed. Sentinel lymph node-negative patients had no further ALND. The SLN identification rate was 98.5% (328 out of 333). In all, 128 out of 328 (39.0%) patients had positive SLNs and complete ALND. A total of 200 out of 328 (61.0%) patients were SLN negative and had no further ALND. The mean tumour size of SLN-negative patients was 16.5 mm. The mean number of SLNs removed was 2.1 per patient. There were no local or axillary recurrences at a median follow-up of 36 months. The absence of axillary recurrences after SLNB without ALND in SLN-negative breast cancer patients supports the hypothesis that SLNB is accurate and safe while providing less surgical morbidity than ALND. Short-term results are very promising that SLNB without ALND in SLN-negative patients is an excellent procedure for axillary staging in a cohort of breast cancer patients with small tumours.

[Sentinel lymph node biopsy in breast cancer patients--results and experience after 500 sentinel lymph node biopsies]. / Die Sentinellymphknotenbiopsie beim Mammakarzinom. Ergebnisse und Erfahrungen nach 500 Sentinellymphknotenbiopsien.

INTRODUCTION: Sentinel lymph node biopsy (SLNB) is a widely used technique for axillary staging in breast cancer patients. The principle to evaluate the axillary status of a breast cancer patient with a less invasive surgery than axillary lymph node dissection (ALND) meets the new minimally invasive concept in breast cancer surgery. Some breast cancer centers proceed to SLNB without ALND in SLN-negative patients. PATIENTS AND METHODS: Between March 1998 and March 2002, 500 SLNBs were performed. After a learning period with SLNB and ALND in 75 patients with a sensitivity of 96.2% and a false-negative rate of 3.8%, SLNB alone without further ALND was performed in a group of patients. In addition, the feasibility of SLNBin patients with locally advanced breast cancer, in patients after neoadjuvant chemotherapy and in patients with multicentricity was evaluated. The combined method with blue dye and technetium-99m-labeled human albumin for identification of SLNs was applied. RESULTS: 500 SLNBs were performed. The identification rate was 86.2%. After exclusion of patients with neoadjuvant chemotherapy and patients with multicentricity, the identification rate was 94.5%. SLNs were positive in 41.3% of patients and negative in 58.7% of patients. DISCUSSION: SLNB is an excellent method for axillary stag-ing and an alternative for ALND in a certain group of breast cancer patients.

Sentinel lymph node biopsy alone without axillary lymph node dissection--follow up of sentinel lymph node negative breast cancer patients.

AIMS: To evaluate the rate of axillary recurrences in sentinel lymph node (SLN) negative breast cancer patients after sentinel lymph node biopsy (SLNB) alone without further axillary lymph node dissection (ALND). METHODS: Between May 1999 and February 2001 all patients who had primary invasive breast cancer and were SLN negative were eligible for this prospective study. SLNB was performed by using the combined method with radioactive tracer and blue dye. SLNs were examined by frozen section, standard H/E staining and immunohistochemistry staining. SLN negative patients did not receive further ALND. Follow-up was done three-monthly with clinical controls, blood samples and ultrasound of the breast and axilla. An annual mammogram was performed. RESULTS: 116 patients with T1 or T2 invasive breast cancer were included in this trial. All 116 patients had negative SLNs in frozen sections, in H/E staining and in immunohistochemistry staining. The mean number of removed SLNs was 2.03+/-1.22. Mean tumor size was 17.15+/-7.62 mm. Postmenopausal patients totalled 79.3 and 20.7% of patients were premenopausal. No local or axillary recurrences occurred at a mean duration of follow-up of 22.12+/-6.38 months. CONCLUSION: The absence of axillary recurrences after SLNB without ALND in SLN negative breast cancer patients supports the hypothesis that SLNB is accurate and safe while providing less surgical morbidity. Short term results are very promising. SLNB without ALND in SLN negative patients is an excellent procedure for axillary staging in a cohort of breast cancer patients with small tumors.

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.

Outer diameter of the vermiform appendix as a sign of acute appendicitis: evaluation at US.

PURPOSE: To evaluate the usefulness and limitations of the outer diameter of the vermiform appendix at cross-sectional ultrasonography to confirm or rule out acute appendicitis. MATERIALS AND METHODS: In a prospective study, outer appendiceal diameters in 240 control subjects and in 278 patients suspected of having acute appendicitis who did (n = 98) or did not (n = 180) have acute appendicitis were measured. RESULTS: Outer appendiceal diameters in the control subjects ranged between 2 and 13 mm, and in 55 (23%) of 240 control subjects, diameters were 6 mm or more. Diameters in the symptomatic patients without acute appendicitis ranged between 2 and 11 mm, and 57 (32%) of 180 patients had diameters of 6 mm or more. Diameters of acutely inflamed appendices ranged between 6 and 30 mm. A diameter of 6 mm or more confirmed acute appendicitis with a sensitivity of 100%; a specificity of 68%; positive and negative predictive values of 63% and 100%, respectively; and an accuracy of 79%. CONCLUSION: The outer appendiceal diameter of 6 mm or more as a sign of acute appendicitis provides high sensitivity but limited specificity. This diagnostic criterion is more useful in excluding acute appendicitis than in confirming it.

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.

Detecting the sentinel lymph node in patients with differentiated thyroid carcinoma.

The aim of this study was to evaluate sentinel lymph node mapping in patients with differentiated thyroid carcinoma. Nine patients with suspected thyroid carcinoma who were scheduled to undergo thyroidectomy underwent scintigraphic localization of sentinel lymph nodes (SLNs). On the day of surgery we injected 37 MBq technetium-99m nanocolloid intratumourally. Dynamic data up to 10 min followed by planar anterior and lateral oblique images up to 1 h after tracer administration were recorded. At surgery the primary tumour was excised first, then the SLNs were removed using a gamma probe. Four patients had papillary carcinoma, two follicular carcinoma, one an oncocytic tumour and two benign tumours. An SLN was identified in all four patients with papillary carcinoma. In the two patients with follicular carcinoma, SLN detection failed. Five patients had one radioactive node, one had three and one had four. In one patient, no SLN was visible with scintigraphic imaging but at surgery three SLNs could be clearly identified using the gamma probe after removal of the primary tumour. There were no false-negative findings. This initial study indicates that in patients with papillary thyroid carcinoma detection of the SLN is possible, whereas the technique failed in two patients with follicular carcinoma. A study on a larger patient sample is now warranted.

[Detection of melanoma metastases with Tc-99m-tetrofosmin]. / Nachweis von Melanommetastasen mit Tc-99m-Tetrofosmin.

AIM: The aim of this study was to evaluate Tc-99m-tetrofosmin whole-body imaging in the detection of metastases in patients with malignant melanoma. METHODS: In 30 patients with suspected melanoma metastases we performed whole body imaging. After administration of about 600 MBq Tc-99m-tetrofosmin dynamic images up to 10 min were performed in 7 patients (1 image per 10 sec) to evaluate the optimal tracer uptake in the metastases. In all patients whole-body images were performed 5-10 min p.i. using an acquisition time of 5 min per image. The final diagnosis was confirmed by surgical histology in 30 lesions, by computertomography and clinical course in the remaining lesions. RESULTS: Out of 64 melanoma metastases 49 were detected using Tc-99m-tetrofosmin scintigraphy (49 rp., 15 fn.). The overall sensitivity for the detection of malignant lesions was 77%. Referring only to the lymph node metastases, the sensitivity was 87% (26 rp.; 4 fn.). The maximal tracer uptake was reached 1 min after injection, with a slow decrease in the following 10 minutes. The size of the lesions ranged between 0.5 and 7.0 cm and the T/B ratios between 1.3 and 3.0 (mean 1.88). CONCLUSIONS: Tc-99m-tetrofosmin whole body imaging is a simple and side-effectless method for the detection of melanoma metastases especially of lymph node metastases. The results are comparable to Tc-99m-sestamibi and Tl-201 scintigraphy.

Presence or absence of gas in the appendix: additional criteria to rule out or confirm acute appendicitis--evaluation with US.

PURPOSE: To investigate whether the presence or absence of gas in the appendix may be considered as additional ultrasonographic (US) criteria to rule out or confirm acute appendicitis. MATERIALS AND METHODS: The appendices in 239 control subjects, 138 patients with lower right quadrant pain without acute appendicitis, and 80 patients with acute appendicitis were prospectively evaluated for intraluminal gas with US. RESULTS: The appendices in 206 (86%) control subjects showed gas at US, and those in 33 (14%) did not. The appendices in 109 (79%) symptomatic patients without acute appendicitis showed gas, and those in 29 (21%) did not. The appendices in 12 (15%) patients with acutely inflamed appendices showed gas, and those in 68 (85%) did not. The absence of gas as a criterion for acute appendicitis had a sensitivity of 85%; specificity, 79%; positive and negative predictive values, 57% and 94%, respectively; and accuracy, 81%. Gas was useful to exclude acute appendicitis in 64 (46%) symptomatic patients because the established criteria were misleading. In 19 (24%) patients, the absence of gas was useful for diagnosis of acute appendicitis because the other criteria were not convincing. CONCLUSION: US-based detection of gas in the appendiceal lumen helps to rule out acute appendicitis, whereas the absence of gas further confirms its presence, especially in cases where established US criteria are either insufficiently present or misleading.

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.

Sclerotic variant of lymphangiomatosis of bone: imaging findings at diagnosis and long-term follow-up.

Lymphangiomatosis is an extremely rare congenital disorder affecting visceral organs and/or the skeletal system. In bone is is usually characterized by multiple lytic lesions with a lacelike pattern and sclerotic margins of various thickness. In this case report we demonstrate the rare sclerotic variant of lymphangiomatosis. We report the development of predominantly sclerotic lesions at different sites by serial radiographs with a long-term follow-up, and show the MRI findings of lymphangiomatosis of the spine.