Interobserver variability and likelihood of malignancy for fifth edition BI-RADS MRI descriptors in non-mass breast lesions.

OBJECTIVE: Non-mass enhancement (NME) in breast MRI is the most common feature of ductal carcinoma in situ (DCIS). We sought to evaluate the interobserver variability and positive predictive value (PPV) for malignancy of NME descriptors using the fifth edition BI-RADS lexicon focusing on the newly introduced "clustered ring enhancement" pattern. MATERIALS AND METHODS: Breast MRIs of 129 patients who had undergone MRI-guided vacuum-assisted biopsy (VAB) in our institution were reviewed. Studies assessed as NME were classified according to the fifth edition BI-RADS lexicon by two breast radiologists. Consensus was reached by involving a third radiologist. Interobserver variability and PPV for malignancy were assessed. RESULTS: Seventy-two of 129 studies were assessed as NME. The disagreement rate in the first assessment step (mass vs. NME) was low at 9.3% (ĸ = 0.81, 95% confidence interval [CI] 0.71-0.91). The disagreement rate for distribution patterns was 23.6% (ĸ = 0.67, 95% CI 0.54-0.80) and 22.2% (ĸ = 0.69, 95% CI 0.56-0.81) for internal enhancement patterns. Clustered ring enhancement (PPV 53.85, p = 0.038) and segmental distribution (PPV 62.5%, p = 0.028) had the highest malignancy rates among internal enhancement and distribution patterns with a significant result; the combination of clustered ring enhancement and segmental distribution raised the malignancy rate by approximately 4% (PPV 66.67%, p = 0.049). CONCLUSION: There was a high agreement rate among readers when differentiating NME from mass lesions. The agreement rate was lower when assessing the distribution and internal enhancement pattern descriptors, but still substantial. The descriptors clustered ring enhancement and segmental distribution were significant predictors of malignancy. KEY POINTS: • Non-mass enhancement is a common morphological feature of non-invasive breast cancer (DCIS) in MRI. Differentiation between potentially malignant and benign changes may be very challenging. • Since clustered ring enhancement and segmental distribution are both significant predictors of malignancy, the awareness of this important finding, combined with high-quality image interpretation skills, may improve the tumor detection rate. • The combination of clustered ring enhancement and segmental distribution increases the positive predictive value for malignancy, which may be relevant for clinical practice.

Correction to: Towards clinical grating-interferometry mammography.

The article Towards clinical grating-interferometry mammography, written by Carolina Arboleda, Zhentian Wang, Konstantins Jefimovs, Thomas Koehler, Udo Van Stevendaal, Norbert Kuhn, Bernd David, Sven Prevrhal, Kristina Lång, Serafino Forte, Rahel Antonia Kubik-Huch, Cornelia Leo.

Towards clinical grating-interferometry mammography.

OBJECTIVES: Grating-interferometry-based mammography (GIM) might facilitate breast cancer detection, as several research works have demonstrated in a pre-clinical setting, since it is able to provide attenuation, differential phase contrast, and scattering images simultaneously. In order to translate this technique to the clinics, it has to be adapted to cover a large field-of-view within a clinically acceptable exposure time and radiation dose. METHODS: We set up a grating interferometer that fits into a standard mammography system and fulfilled the aforementioned conditions. Here, we present the first mastectomy images acquired with this experimental device. RESULTS AND CONCLUSION: Our system performs at a mean glandular dose of 1.6 mGy for a 5-cm-thick, 18%-dense breast, and a field-of-view of 26 × 21 cm2. It seems to be well-suited as basis for a clinical-environment device. Further, dark-field signals seem to support an improved lesion visualization. Evidently, the effective impact of such indications must be evaluated and quantified within the context of a proper reader study. KEY POINTS: • Grating-interferometry-based mammography (GIM) might facilitate breast cancer detection, since it is sensitive to refraction and scattering and thus provides additional tissue information. • The most straightforward way to do grating-interferometry in the clinics is to modify a standard mammography device. • In a first approximation, the doses given with this technique seem to be similar to those of conventional mammography.

Breast-density assessment with hand-held ultrasound: A novel biomarker to assess breast cancer risk and to tailor screening?

OBJECTIVES: To assess feasibility and diagnostic accuracy of a novel hand-held ultrasound (US) method for breast density assessment that measures the speed of sound (SoS), in comparison to the ACR mammographic (MG) categories. METHODS: ACR-MG density (a=fatty to d=extremely dense) and SoS-US were assessed in the retromamillary, inner and outer segments of 106 women by two radiographers. A conventional US system was used for SoS-US. A reflector served as timing reference for US signals transmitted through the breasts. Four blinded readers assessed average SoS (m/s), ΔSoS (segment-variation SoS; m/s) and the ACR-MG density. The highest SoS and ΔSoS values of the three segments were used for MG-ACR whole breast comparison. RESULTS: SoS-US breasts were examined in <2 min. Mean SoS values of densities a-d were 1,421 m/s (SD 14), 1,432 m/s (SD 17), 1,448 m/s (SD 20) and 1,500 m/s (SD 31), with significant differences between all groups (p<0.001). The SoS-US comfort scores and inter-reader agreement were significantly better than those for MG (1.05 vs. 2.05 and 0.982 vs. 0.774; respectively). A strong segment correlation between SoS and ACR-MG breast density was evident (rs=0.622, p=<0.001) and increased for full breast classification (rs=0.746, p=<0.001). SoS-US allowed diagnosis of dense breasts (ACR c and d) with sensitivity 86.2 %, specificity 85.2 % and AUC 0.887. CONCLUSIONS: Using hand-held SoS-US, radiographers measured breast density without discomfort, readers evaluated measurements with high inter-reader agreement, and SoS-US correlated significantly with ACR-MG breast-density categories. KEY POINTS: • The novel speed-of-sound ultrasound correlated significantly with mammographic ACR breast density categories. • Radiographers measured breast density without women discomfort or radiation. • SoS-US can be implemented on a standard US machine. • SoS-US shows potential for a quantifiable, cost-effective assessment of breast density.

Stereotactic Vacuum-Assisted Breast Biopsy in Ductal Carcinoma in situ: Residual Microcalcifications and Intraoperative Findings.

PURPOSE: The question of overtreatment of ductal carcinoma in situ (DCIS) was raised because a significant proportion of especially low-grade DCIS lesions never progress to invasive cancer. The rationale for the present study was to analyze the value of stereotactic vacuum-assisted biopsy (VAB) for complete removal of DCIS, focusing on the relationship between the absence of residual microcalcifications after stereotactic VAB and the histopathological diagnosis of the definitive surgical specimen. PATIENTS AND METHODS: Data of 58 consecutive patients diagnosed with DCIS by stereotactic VAB in a single breast center between 2012 and 2017 were analyzed. Patient records from the hospital information system were retrieved, and mammogram reports and images as well as histopathology reports were evaluated. The extent of microcalcifications before and after biopsy as well as the occurrence of DCIS in biopsy and definitive surgical specimens were analyzed and correlated. RESULTS: There was no correlation between the absence of residual microcalcifications in the post-biopsy mammogram and the absence of residual DCIS in the final surgical specimen (p = 0.085). Upstaging to invasive cancer was recorded in 4 cases (13%) but occurred only in the group that had high-grade DCIS on biopsy. Low-grade DCIS was never upgraded to high-grade DCIS in the definitive specimen. CONCLUSIONS: The radiological absence of microcalcifications after stereotactic biopsy does not rule out residual DCIS in the final surgical specimen. Since upstaging to invasive cancer is seen in a substantial proportion of high-grade DCIS, the surgical excision of high-grade DCIS should remain the treatment of choice.

Can grating interferometry-based mammography discriminate benign from malignant microcalcifications in fresh biopsy samples?

PURPOSE: In addition to absorption imaging, grating interferometry-based mammography (GIM) is capable of detecting differential-phase and scattering signals. In particular, the scattering signal can enable a quantifiable characterization of breast lesions. The purpose of this study was to determine if suspicious microcalcifications associated with benign or malignant lesions can be discriminated based on their absorption and scattering properties. MATERIALS AND METHODS: In this prospective, ethically approved study, 62 patients (mean age 60 y, range 39-89) with suspicious microcalcifications, who underwent stereotactic biopsies, were included. Biopsies were measured with an experimental GIM device and the ratios of the scattering and absorption signal (R-value) for microcalcifications were calculated. The mean R-values for benign and malignant lesions associated with microcalcifications were compared with the final histopathological diagnosis using a t-test. RESULTS: Twenty of the 62 participants had microcalcifications associated with malignancy. Comparing the two largest histopathological sub-groups of fibrosis (n = 23) vs. ductal carcinoma in situ (n = 15) resulted in an average R-value of 4.08 for benign and 2.80 for malignant lesions; p = 0.07. All microcalcifications associated with malignancy had an R-value below 4.71. Excluding microcalcifications with an R-value above this threshold would result in an 11 % reduction of false positives. CONCLUSION: The novel GIM modality has the potential to non-invasively characterize microcalcifications and might aid in the discrimination of benign from malignant lesions in fresh biopsy samples.

Invasive ductal carcinoma detected within a fibroadenolipoma through digital breast tomosynthesis.

A 52-year-old patient referred to our hospital for a screening mammogram showed a suspicious new architectural distortion. Previously, a fibroadenolipoma within the right breast was diagnosed clinically and radiologically. Further work-up with tomosynthesis, magnetic resonance imaging, and magnetic resonance-guided biopsy showed an invasive ductal carcinoma within the fibroadenolipoma, which are usually benign breast lesions not associated with malignancy. This case report offers a review of the literature and a discussion of signs, which should alert the radiologist.

Microbubbles as a contrast agent in grating interferometry mammography: an ex vivo proof-of-mechanism study.

Grating interferometry mammography (GIM) is an experimental breast imaging method at the edge of being clinically implemented. Besides attenuation, GIM can measure the refraction and scattering of x-rays resulting in differential phase contrast (DPC) and dark-field (DF) images. In this exploratory study, we assessed the feasibility of using microbubbles as a contrast agent in GIM. Two millilitres of microbubbles and iodine were respectively injected into ex vivo breast phantoms, consisting of fresh chicken breasts. Native and postcontrast images were acquired with a clinically compatible GIM setup, operated at 38 kVp, 14-s acquisition time, and with a dose of 1.3 mGy. The visibility of the contrast agents was analysed in a side-by-side comparison by three radiologists. The contrast-to-noise-ratio (CNR) was calculated for each contrast agent. We found that both contrast agents were judged to be visible by the readers. The mean CNR was 3.1 ± 1.9 for microbubbles in DF and 24.2 ± 6.5 for iodine in attenuation. In conclusion, this is a first proof-of-mechanism study that microbubbles could be used as a contrast agent in clinically compatible GIM, due to their scattering properties, which implies the potential use of a contrast agent with a high safety profile in x-ray-based breast imaging.

Breast Density Assessment in Young Women with Ultrasound based on Speed of Sound: Influence of the Menstrual Cycle.

To investigate changes in breast density (BD) during the menstrual cycle in young women in comparison to inter-breast and -segment changes as well as reproducibility of a novel Speed-of-Sound (SoS) Ultrasound (US) method.SoS-US uses a conventional US system with a reflector and a software add-on to quantify SoS in the retro-mammillary, inner and outer segments of both breasts. Twenty healthy women (18-40 years) with regular menstrual cycles were scanned twice with two weeks in-between. Three of these were additionally measured twice per week for 25 days. Average SoS (m/s) and ΔSoS (segment-variation SoS; m/s) were measured. Variations between follicular and luteal phases and changes over the four-week period were assessed. Inter-examiner and inter-reader agreements were also evaluated. Variances between cycle phases, examiners and readers were compared.No significant SoS difference was observed between follicular and luteal phases for the twenty women (P = .126), and between all different days for the three more frequently measured women (P = .892). Inter-reader (ICC = 0.999) and inter-examiner (ICC = 0.990) agreements were high. The SoS variance due to menstrual variations was not significantly larger than the inter-examiner uncertainty (P = .461). Inter-reader variations were significantly smaller than menstrual and examiner variations (P < .001).SoS-US showed high inter-examiner and inter-reader reproducibility. The alterations during the menstrual cycles were not significantly larger than the confidence interval of measurements.

Feasibility of breast MRI after sentinel procedure for breast cancer with superparamagnetic tracers.

RATIONALE: The gold standard for detection of axillary sentinel lymph nodes uses injection of a radioisotope (99Tc Nanocoll). As an alternative to this method, a magnetometer detecting the superparamagnetic tracer Sienna+® can be applied for detection of sentinel lymph nodes. The goal of this study was to determine whether interpretation of breast MRI is impaired by Sienna+® tracer residues in the operated breast and axillary lymph nodes after a sentinel procedure using this tracer. PATIENTS AND METHODS: 34 patients who received the Sienna+® tracer for marking the sentinel node were invited to undergo a follow-up breast MRI. Native MR images were obtained from breast and axilla. The breast MRIs were evaluated by two independent breast radiologists for Sienna+® tracer related artefacts and for the degree of impairment of the MR imaging. RESULTS: 24 of the 34 invited patients took part in this study. The mean time since injection of Sienna+® was 42 months (40.6-45.4 months). Two patients had bilateral surgery with injections in both breasts, leading to a total of 26 separate cases. One case had to be excluded due to breathing artefacts. In 10 cases (40%), impaired imaging was found. In three cases (12%), the MRI scan reading was impossible due to Sienna+® tracer residues, the other 12 cases (48%) showed no restriction. In the subgroup of patients treated with breast conserving surgery, tracer residue artefacts were found in 13 of 17 patients (76.5%). CONCLUSION: To our knowledge, in this study for the first time MR feasibility after Sienna injection was investigated. Sienna+® impaired breast MRI after a mean follow-up time of 42 months in half of the cases. Further research is needed to investigate time and field-strength dependency of tracer detectability as well as the diagnostic impact of these artifacts on contrast-enhanced imaging in a clinical setting.

Unusual location of a urinary bladder cancer metastasis.

Bladder cancer is the fourth most common malignancy among men in the Western world. Bone metastasis occurs in 27 % of the cases. Usually, the location is the spine. The present report describes the first case of a proven distant bone metastasis to the acromion from a urinary bladder carcinoma in a patient with shoulder pain.