Half-time bone scintigraphy in prostate and breast cancer patients.

BACKGROUND: Developments in image reconstruction techniques for planar imaging, also known as enhanced planar processing (EPP), enable the possibility to reconstruct planar scintigraphic images with low count statistics, providing the opportunity to reduce image acquisition time. In this study, the performance of EPP for oncologic half-time bone scintigraphy images was evaluated. METHODS: The EPP software was evaluated for different imaging conditions using standardized phantom experiments. Additionally, 51 patients with prostate and breast cancer were prospectively included and underwent bone scintigraphy using a standard and half-time protocol. Independent reading was performed on three image types (standard, half-time non-processed, and half-time EPP) by three observers, scoring the number and anatomical location of lesions, image quality, and diagnostic confidence by which the definitive diagnosis was made. RESULTS: EPP images had improved contrast and lower noise levels compared to the non-processed half-time images. It was determined that EPP images acquired at double scan speed had similar image quality to the standard non-processed images. There was substantial agreement with respect to diagnosis and diagnostic confidence based on all three image types between the observers. Image quality in the EPP images was higher with respect to the non-processed half-time images, and was comparable to the standard images. CONCLUSIONS: Diagnostic confidence was not affected by reduction in image acquisition time. There was substantial agreement between all three observers with respect to the diagnosis provided in all three image types. Subjective and objective image quality improved when half-time images were processed with EPP software.

Early myocardial deformation abnormalities in breast cancer survivors.

To evaluate the role of 2D myocardial strain (rate) imaging in the detection of early subclinical cardiotoxicity in breast cancer survivors treated with an anthracycline-based chemotherapeutic regimen. 57 adult breast cancer survivors were analyzed 1 year after therapy. All patients underwent biomarker analysis and 2D echocardiography consisting of conventional echocardiographic and strain (rate) parameters. Conventional echocardiographic values were normal. Global longitudinal strain was normal, but 18 % of patients showed a >2 SD decrease when individually compared to reference values. This subgroup showed a decrease in end-systolic and end-diastolic volumes and an increase in left ventricular mass. Radial and circumferential strain rates were significantly decreased in the whole study group. 2D myocardial strain (rate) imaging showed abnormalities in breast cancer survivors, while conventional echocardiographic values remained normal, rendering 2D myocardial strain (rate) imaging an interesting tool for the early detection of anthracycline-induced cardiotoxicity.

Cardiac molecular pathways influenced by doxorubicin treatment in mice.

Doxorubicin (DOX) is a potent chemotherapeutic with distinct cardiotoxic properties. Understanding the underlying cardiotoxic mechanisms on a molecular level would enable the early detection of cardiotoxicity and implementation of prophylactic treatment. Our goal was to map the patterns of different radiopharmaceuticals as surrogate markers of specific metabolic pathways induced by chemotherapy. Therefore, cardiac distribution of 99mTc-sestamibi, 99mTc-Annexin V, 99mTc-glucaric acid and [18F]FDG and cardiac expression of Bcl-2, caspase-3 and -8, TUNEL, HIF-1α, and p53 were assessed in response to DOX exposure in mice. A total of 80 mice (64 treated, 16 controls) were evaluated. All radiopharmaceuticals showed significantly increased uptake compared to controls, with peak cardiac uptake after one (99mTc-Annexin V), two (99mTc-sestamibi), three ([18F]FDG), or four (99mTc-glucaric acid) cycles of DOX. Strong correlations (p < 0.01) were observed between 99mTc-Annexin V, caspase 3 and 8, and TUNEL, and between [18F]FDG and HIF-1α. This suggests that the cardiac DOX response starts with apoptosis at low exposure levels, as indicated by 99mTc-Annexin V and histological apoptosis markers. Late process membrane disintegration can possibly be detected by 99mTc-sestamibi and 99mTc-glucaric acid. [18F]FDG signifies an early adaptive response to DOX, which can be further exploited clinically in the near future.

Relationship of promising methods in the detection of anthracycline-induced cardiotoxicity in breast cancer patients.

PURPOSE: It remains challenging to identify patients at risk of anthracycline-induced cardiotoxicity. To better understand the different risk-stratifying approaches, we evaluated (123)I-metaiodobenzylguanidine ((123)I-mIBG) scintigraphy and its interrelationship with conventional echocardiography, 2D strain imaging and several biomarkers. METHODS: We performed (123)I-mIBG scintigraphy, conventional and strain echocardiography and biomarker (NT-proBNP, TNF-α, galectin-3, IL-6, troponin I, ST-2 and sFlt-1) assessment in 59 breast cancer survivors 1 year after anthracycline treatment. Interobserver and intermethod variability was calculated on planar and SPECT (123)I-mIBG scintigraphy, using the heart/mediastinum (H/M) ratio and washout (WO). Pearson's r and multivariate analyses were performed to identify correlations and independent predictors of (123)I-mIBG scintigraphy results. RESULTS: Delayed planar anterior whole-heart ROI (WH) H/M ratios and WO were the most robust (123)I-mIBG parameters. Significant correlations were observed between (123)I-mIBG parameters and several conventional echo parameters, global longitudinal and radial strain (GLS and GRS) and galectin-3. The highest Pearson's r was observed between delayed H/M ratio and GRS (Pearson's r 0.36, p = 0.01). Multivariate analysis showed that GRS was the only independent predictor of the delayed WH H/M ratio (p = 0.023). CONCLUSION: The delayed planar H/M ratio is the most robust (123)I-mIBG parameter. It correlates with several conventional echocardiographic parameters, GLS, GRS and galectin-3. Of these, only GRS predicts the H/M ratio.

[FDG-PET/CT in staging of breast carcinoma: use in tumour stage III and locoregional recurrent breast carcinoma]. / FDG-PET/CT bij stadiëring van mammacarcinoom: toepassing bij tumorstadium III en locoregionaal recidief.

In stage III breast carcinoma, metastasized disease needs to be determined. In the past, conventional imaging by liver ultrasound, chest X-ray and bone scintigraphy was the work-up of choice. Recently, FDG-PET/CT was found to have additional value, but clinicians are hesitant to introduce this technique. We present three patients in whom FDG-PET/CT was applied. A 61-year-old woman with stage III breast carcinoma after conventional work-up was upstaged to stage IV breast carcinoma by FDG-PET/CT, upon which her treatment was changed. A 55-year-old woman suspected of stage IV breast carcinoma after conventional imaging was downstaged to stage III after FDG-PET/CT. Her treatment was changed as well. In a 78-year-old woman with recurrent breast carcinoma, the diagnostic certainty of stage III breast carcinoma was increased by FDG-PET/CT. We conclude that FDG-PET/CT is valuable for adequately diagnosing metastases in patients with stage III breast carcinoma and can replace conventional imaging.