Diagnostic performance of PET/computed tomography versus PET/MRI and diffusion-weighted imaging in the N- and M-staging of breast cancer patients.

OBJECTIVE: To provide a systematic review regarding the diagnostic performance of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) and diffusion-weighted imaging (DWI) compared to 18F-FDG PET/computed tomography (CT) focused on nodal and distant staging in breast cancer patients. METHODS: The PubMed and Embase databases were searched for relevant publications until April 2020. Two independent reviewers searched for eligible articles based on predefined in- and exclusion criteria, assessed quality and extracted data. RESULTS: Eleven eligible studies were selected from 561 publications identified by the search. In seven studies, PET/CT was compared with PET/MRI, and in five, PET/CT with DWI. Significantly higher sensitivity for PET/MRI compared to PET/CT in a lesion-based analysis was reported for all lesions together (77% versus 89%) in one study, osseous metastases (69-99% versus 92-98%) in two studies and hepatic metastases (70-75% versus 80-100%) in one study. Moreover, PET/MRI revealed a significantly higher amount of osseous metastases (90 versus 141) than PET/CT. PET/CT is associated with a statistically higher specificity than PET/MRI in the lesion detection of all lesions together (98% versus 96%) and of osseous metastases (100% versus 95%), both in one study. None of the reviewed studies reported significant differences between PET/CT and DWI for any of the evaluated sites. There is a trend toward higher specificity for PET/CT. CONCLUSION: In general, there is a trend toward higher sensitivity and lower specificity of PET/MRI when compared to PET/CT. Results on the diagnostic performance of DWI are conflicting. Rather than evaluating it separate, it seems to have complementary value when combined with other MR sequences.

Current perspective: Osimertinib-induced QT prolongation: new drugs with new side-effects need careful patient monitoring.

An increasing number of tyrosine kinase inhibitors (TKIs) are available for the treatment of non-small cell lung cancer (NSCLC). QT prolongation is one of the known, but relatively rare, adverse events of several TKIs (e.g. osimertinib, crizotinib, ceritinib). Screening for QT prolongation in (high risk) patients is advised for these TKIs. When a QT prolongation develops, the physician is challenged with the question whether to (permanently) discontinue the TKI. In this perspective, we report on a patient who developed a grade III QT prolongation during osimertinib (a third-generation epidermal growth factor receptor [EGFR]-TKI) treatment. On discontinuation of osimertinib, she developed a symptomatic disease flare, not responding to subsequent systemic treatment. The main aim of this perspective is to describe the management of QT prolongation in stage IV EGFR driver mutation NSCLC patients. We also discuss the ethical question of how to weigh the risk of a disease flare due to therapy cessation against the risk of sudden cardiac death. A family history of sudden death and a prolonged QT interval might indicate a familiar long QT syndrome. We have summarised the current monitoring advice for TKIs used in the treatment of lung cancer and the most common drug-TKI interactions to consider and to optimise TKI treatment in lung cancer patients.

Radiation exposure of digital breast tomosynthesis using an antiscatter grid compared with full-field digital mammography.

OBJECTIVES: Our study aim was to assess the radiation dose of digital breast tomosynthesis (DBT) in comparison to full-field digital mammography (FFDM) in a clinical setting. MATERIALS AND METHODS: Two-hundred four patients were consecutively included, of which 236 complementary DBT and FFDM examinations were available. All acquisitions were performed on a single commercially available mammography system capable of FFDM and DBT acquisitions using an antiscatter grid. The average glandular dose (AGD) was calculated for each examination using the Dance method. For this, tube output and half-value layer were measured, and the required exposure parameters (target/filter material, tube voltage, tube load, compressed breast thickness) were retrieved from the DICOM metadata. The DBT and FFDM AGD values were pairwise tested, and a subanalysis with respect to breast thickness was performed. RESULTS: The mean (SD) AGD values for a single-view DBT and FFDM were 1.49 (0.36) mGy and 1.62 (0.55) mGy, respectively, which are small but statistically significant differences. This difference may be partially attributed to the small difference in the mean breast thickness between FFDM and DBT (3 mm). In this patient population, the AGD was lower for DBT than for FFDM in 61% of the patients. When patients were categorized according to breast thickness, the AGD of DBT was only significantly smaller than the AGD of FFDM for breast thickness categories larger than 50 mm, indicating that the dose reduction for DBT compared with FFDM was more pronounced in thick breasts. CONCLUSIONS: The radiation dose of patients undergoing a single-view DBT was comparable to a single-view FFDM. For patients with thicker breasts, the radiation dose of DBT was slightly lower than FFDM.

CT-Guided Percutaneous Transthoracic Needle Biopsies Using 10G Large-Core Needles: Initial Experience.

PURPOSE: Using large-core biopsy needles in CT-guided percutaneous transthoracic needle biopsies (PTNB) may be advantageous in terms of larger specimens, which facilitate more extensive histopathological, immunohistochemical, and molecular examination of tumor tissue. The aim of this study was to evaluate the success rate and safety in CT-guided PTNB using 10G large-core biopsy needles. METHODS AND MATERIALS: 35 patients with intrathoracic lesions suspected of malignancy underwent CT-guided PTNB using dedicated large-core biopsy needles (10G Spirotome™, Medinvents, Hasselt, Belgium). Location, tumor size, number of pleural passes, number of biopsies, histologic result, and complications (pneumothorax, bleeding) were recorded. RESULTS: Lesion location varied from pleural to hilar location. Mean tumor size was 3.5 cm (range 0.7-9.2 cm). Only one pleural passage was necessary in all patients. Mean distance from the pleura to the lesion was 2.6 cm (max 9.2 cm). Large-core biopsy (10G) was successful in 88.6%. Pneumothorax was found in 40%. Minor intraparenchymal bleeding was present in 14 patients. No major complications were recorded. CONCLUSION: Large-core biopsy with 10G did not show higher complication rates compared to literature. It is technically feasible and safe. The obtained larger specimens may especially be helpful for the increasing demands of extensive molecular analysis for stratified patient care.

The quality of tumor size assessment by contrast-enhanced spectral mammography and the benefit of additional breast MRI.

Background - Contrast-enhanced spectral mammography (CESM) is a promising new breast imaging modality that is superior to conventional mammography for breast cancer detection. We aimed to evaluate correlation and agreement of tumor size measurements using CESM. As additional analysis, we evaluated whether measurements using an additional breast MRI exam would yield more accurate results. Methods - Between January 1(st) 2013 and April 1(st) 2014, 87 consecutive breast cancer cases that underwent CESM were collected and data on maximum tumor size measurements were gathered. In 57 cases, tumor size measurements were also available for breast MRI. Histopathological results of the surgical specimen served as gold standard in all cases. Results - The Pearson's correlation coefficients (PCC) of CESM versus histopathology and breast MRI versus histopathology were all >0.9, p<0.0001. For the agreement between measurements, the mean difference between CESM and histopathology was 0.03 mm. The mean difference between breast MRI and histopathology was 2.12 mm. Using a 2x2 contingency table to assess the frequency distribution of a relevant size discrepancy of >1 cm between the two imaging modalities and histopathological results, we did not observe any advantage of performing an additional breast MRI after CESM in any of the cases. Conclusion - Quality of tumor size measurement using CESM is good and matches the quality of these measurement assessed by breast MRI. Additional measurements using breast MRI did not improve the quality of tumor size measurements.

Value of gadofosveset-enhanced MRI and multiplanar reformatting for selecting good responders after chemoradiation for rectal cancer.

OBJECTIVES: Our primary objective was to evaluate diagnostic performance of gadofosveset T1-weighted magnetic resonance imaging (T1W MRI) for discriminating between ypT0-2 and ypT3-4 tumours after chemoradiation therapy (CRT) for rectal cancer compared with T2W MRI for a general and expert reader. Second objectives included assessing the value of multiplanar reformatting (MPR) and interobserver agreement. METHODS: A general and expert reader evaluated 49 patients for likelihood of ypT0-2 tumour after CRT on T2W, gadofosveset T1W MRI, and gadofosveset T1W MRI + T2W MRI. The general reader scored with and without MPR. Confidence level scores were used to construct receiver-operating characteristic (ROC) curves. Area under the curve (AUC) values and diagnostic parameters were calculated and compared. RESULTS: Gadofosveset T1W MRI + T2W MRI showed slightly superior sensitivity than T2W MRI for the general but not the expert reader. Specificity was higher for the expert on gadofosveset T1W MRI only compared with T2W MRI only (100% vs. 82%). MPR did not increase diagnostic performance. Interobserver agreement was highest for the combination of gadofosveset-enhanced T1W imaging plus T2W MRI. CONCLUSIONS: The sole use or addition of gadofosveset-enhanced T1W MRI to T2W MRI did not increase significantly diagnostic performance for assessing ypT0-2 tumours. Adding gadofosveset-enhanced T1W MRI slightly increased sensitivity for the general reader and specificity for the expert reader, but this increase was not significant for more accurate clinical decision making. MPR did not improve diagnostic performance. KEY POINTS: • ycT restaging with MRI in rectal cancer is challenging. • Gadofosveset-enhanced T1W MRI has shown promise for nodal restaging. • Gadofosveset-enhanced T1W MRI did not significantly increase diagnostic performance for assessing ypT0-2-tumours. • Addition of the gadofosveset sequence to T2W MRI slightly increased sensitivity for the general reader. • MPR did not improve diagnostic performance of ycT staging.

Contrast-enhanced dual-energy mammography: a promising new imaging tool in breast cancer detection.

Contrast-enhanced dual-energy mammography (CEDM) is a promising new breast imaging tool for breast cancer detection. In CEDM, an iodine-based contrast agent is intravenously administered and subsequently, dual-energy mammography is performed. This results in a set of images containing both a regular mammogram and an image that contains contrast enhancement information. Preliminary studies have indicated that CEDM is superior to conventional mammography and might even match the diagnostic performance of breast MRI. In this review, the imaging technique, protocol and patient handling of CEDM is presented. Furthermore, an overview of current results on CEDM and potential future indications are outlined.

Radiation exposure of contrast-enhanced spectral mammography compared with full-field digital mammography.

OBJECTIVES: Contrast-enhanced spectral mammography (CESM) shows promising initial results but comes at the cost of increased dose as compared with full-field digital mammography (FFDM). We aimed to quantitatively assess the dose increase of CESM in comparison with FFDM. MATERIALS AND METHODS: Radiation exposure-related data (such as kilovoltage, compressed breast thickness, glandularity, entrance skin air kerma (ESAK), and average glandular dose (AGD) were retrieved for 47 CESM and 715 FFDM patients. All examinations were performed on 1 mammography unit. Radiation dose values reported by the unit were validated by phantom measurements. Descriptive statistics of the patient data were generated using a statistical software package. RESULTS: Dose values reported by the mammography unit were in good qualitative agreement with those of phantom measurements. Mean ESAK was 10.5 mGy for a CESM exposure and 7.46 mGy for an FFDM exposure. Mean AGD for a CESM exposure was 2.80 mGy and 1.55 mGy for an FFDM exposure. CONCLUSIONS: Compared with our institutional FFDM, the AGD of a single CESM exposure is increased by 1.25 mGy (+81%), whereas ESAK is increased by 3.07 mGy (+41%). Dose values of both techniques meet the recommendations for maximum dose in mammography.

Contrast-enhanced spectral mammography in patients referred from the breast cancer screening programme.

OBJECTIVES: Feasibility studies have shown that contrast-enhanced spectral mammography (CESM) increases diagnostic accuracy of mammography. We studied diagnostic accuracy of CESM in patients referred from the breast cancer screening programme, who have a lower disease prevalence than previously published papers on CESM. METHODS: During 6 months, all women referred to our hospital were eligible for CESM. Two radiologists blinded to the final diagnosis provided BI-RADS classifications for conventional mammography and CESM. Statistical significance of differences between mammography and CESM was calculated using McNemar's test. Receiver operating characteristic (ROC) curves were constructed for both imaging modalities. RESULTS: Of the 116 eligible women, 113 underwent CESM. CESM increased sensitivity to 100.0% (+3.1%), specificity to 87.7% (+45.7%), PPV to 76.2% (+36.5%) and NPV to 100.0% (+2.9%) as compared to mammography. Differences between conventional mammography and CESM were statistically significant (p < 0.0001). A similar trend was observed in the ROC curve. For conventional mammography, AUC was 0.779. With CESM, AUC increased to 0.976 (p < 0.0001). In addition, good agreement between tumour diameters measured using CESM, breast MRI and histopathology was observed. CONCLUSION: CESM increases diagnostic performance of conventional mammography, even in lower prevalence patient populations such as referrals from breast cancer screening. KEY POINTS: • CESM is feasible in the workflow of referrals from routine breast screening. • CESM is superior to mammography, even in low disease prevalence populations. • CESM has an extremely high negative predictive value for breast cancer. • CESM is comparable to MRI in assessment of breast cancer extent. • CESM is comparable to histopathology in assessment of breast cancer extent.