Integrating clinical research in an operative screening and diagnostic breast imaging department: First experience, results and perspectives using microwave imaging.

Rationale and objectives: Clinical research is crucial for evaluating new medical procedures and devices. It is important for healthcare units and hospitals to minimize the disruptions caused by conducting clinical studies; however, complex clinical pathways require dedicated recruitment and study designs.This work presents the effective introduction of novel microwave breast imaging (MBI), via MammoWave apparatus, into the clinical routine of an operative screening and diagnostic breast imaging department for conducting a multicentric clinical study. Materials and methods: Microwave breast imaging, using MammoWave apparatus, was performed on volunteers coming from different clinical pathways. Clinical data, comprising demographics and conventional radiologic reports (used as reference standard), was collected; a satisfaction questionnaire was filled by every volunteer. Microwave images were analyzed by an automatic clinical decision support system, which quantified their corresponding features to discriminate between breasts with no relevant radiological findings (NF) and breasts with described findings (WF). Results: Conventional breast imaging (DBT, US, MRI) and MBI were performed and adapted to assure best clinical practices and optimum pathways. 180 volunteers, both symptomatic and asymptomatic, were enrolled in the study. After microwave images' quality assessment, 48 NF (15 dense) and 169 WF (88 dense) breasts were used for the prospective study; 48 (18 dense) breasts suffered from a histology-confirmed carcinoma. An overall sensitivity of 85.8 % in breasts lesions' detection was achieved by the microwave imaging apparatus. Conclusion: An optimum recruitment strategy was implemented to assess MBI. Future trials may show the clinical usefulness of microwave imaging, which may play an important role in breast screening.

Dielectric Characterization of Breast Biopsied Tissues as Pre-Pathological Aid in Early Cancer Detection: A Blinded Feasibility Study.

Dielectric characterization has significant potential in several medical applications, providing valuable insights into the electromagnetic properties of biological tissues for disease diagnosis, treatment planning, and monitoring of therapeutic interventions. This work presents the use of a custom-designed electromagnetic characterization system, based on an open-ended coaxial probe, for discriminating between benign and malignant breast tissues in a clinical setting. The probe's development involved a well-balanced compromise between physical feasibility and its combined use with a reconstruction algorithm known as the virtual transmission line model (VTLM). Immediately following the biopsy procedure, the dielectric properties of the breast tissues were reconstructed, enabling tissue discrimination based on a rule-of-thumb using the obtained dielectric parameters. A comparative analysis was then performed by analyzing the outcomes of the dielectric investigation with respect to conventional histological results. The experimental procedure took place at Complejo Hospitalario Universitario de Toledo-Hospital Virgen de la Salud, Spain, where excised breast tissues were collected and subsequently analyzed using the dielectric characterization system. A comprehensive statistical evaluation of the probe's performance was carried out, obtaining a sensitivity, specificity, and accuracy of 81.6%, 61.5%, and 73.4%, respectively, compared to conventional histological assessment, considered as the gold standard in this investigation.

A Multicentric, Single Arm, Prospective, Stratified Clinical Investigation to Confirm MammoWave's Ability in Breast Lesions Detection.

Novel techniques, such as microwave imaging, have been implemented in different prototypes and are under clinical validation, especially for breast cancer detection, due to their harmless technology and possible clinical advantages over conventional imaging techniques. In the prospective study presented in this work, we aim to investigate through a multicentric European clinical trial (ClinicalTrials.gov Identifier NCT05300464) the effectiveness of the MammoWave microwave imaging device, which uses a Huygens-principle-based radar algorithm for image reconstruction and comprises dedicated image analysis software. A detailed clinical protocol has been prepared outlining all aspects of this study, which will involve adult females having a radiologist study output obtained using conventional exams (mammography and/or ultrasound and/or magnetic resonance imaging) within the previous month. A maximum number of 600 volunteers will be recruited at three centres in Italy and Spain, where they will be asked to sign an informed consent form prior to the MammoWave scan. Conductivity weighted microwave images, representing the homogeneity of the tissues' dielectric properties, will be created for each breast, using a conductivity = 0.3 S/m. Subsequently, several microwave image parameters (features) will be used to quantify the images' non-homogenous behaviour. A selection of these features is expected to allow for distinction between breasts with lesions (either benign or malignant) and those without radiological findings. For all the selected features, we will use Welch's t-test to verify the statistical significance, using the gold standard output of the radiological study review.

Diagnostic value of halo sign in young women (aged 45 to 49 years) in a breast screening programme with synthesized 2D mammography.

OBJECTIVE:: To assess the clinical performance of the halo sign in tomosynthesis and synthesized 2D mammography, and to identify age groups where its diagnostic value may be greater. METHODS:: 183 patients with nodules were recalled from the breast screening programme (with tomosynthesis and 2D synthesized mammograms). The patients were separated into two groups, 45-49 years and 50-69 years, and depending on the presence or not of halo sign. We calculated the predictive values for the different age groups. RESULTS:: In 45-49 years group, 86 nodular lesions were recalled, 66 (76.7%) with positive halo sign and 20 (23.3%) with negative halo sign. In positive halo sign group, biopsy was considered in 23 (34.8%), with histological features of benignity. In 50-69 years group, 98 nodular lesions from 97 patients were recalled, 51 (52%) with positive halo sign and 47 (48%) with negative halo sign. In positive halo sign group, biopsy was considered in 13 (25.5%); four (30.8%) were malignant and nine (69.2%) were benign. CONCLUSION:: Halo sign could be considered as a marker of benign lesion in females < 50 years. In females ≥ 50 years, other breast imaging techniques should be considered, with or without histological studies, to rule out malignancy. ADVANCES IN KNOWLEDGE:: The trend of a positive halo sign to act as a marker of benign lesion could be improve the recall rate and positive predictive values in the breast screening programme with tomosynthesis and synthesized 2D mammography, especially in young females.

Valoración de las categorías BI-RADS ® de la densidad mamaria entre radiólogos y respecto a un método cuantitativo de medición / Evaluation of the BI-RADS® categories between readers and with regard to a quantitative method

Objetivo. Valorar la concordancia al clasificar las densidades mamarias empleando el sistema BI-RADS® y la variabilidad entre este método empleado por un lector experto en comparación con los valores obtenidos mediante un sistema de medición automática (Quantra®). Pacientes y métodos. Estudio descriptivo en 2 fases. Primero se evaluó la clasificación BI-RADS® de 5 lectores de una muestra seleccionada de forma aleatoria y estratificada por grupos (516 pacientes), para medir la variabilidad intraobservador e interobservador (índice kappa). Finalmente se analizó la concordancia entre el radiólogo con más experiencia y el software Quantra® que permite la valoración volumétrica de la densidad. Resultados. La concordancia por parejas varió entre débil a moderada (kappa 0,35-0,67), el grupo presentó un valor moderado de reproducibilidad (0,58), siendo mayor en las densidades extremas y en los grupos de edad límite. La variabilidad intraobservador fue de moderada a buena (0,52-0,79). Respecto a la clasificación de la densidad por categorías entre el lector experto y la aplicación, no se evidenció concordancia (kappa = 0,0737). Conclusiones. Los valores de concordancia obtenidos corroboran la evidencia descrita en la literatura, considerando que la lectura la realizaron radiólogos con experiencia y dedicación exclusiva en mama. No se apreció concordancia en la clasificación lector versus Quantra® (esta pondera las densidades en menor porcentaje respecto al análisis visual), y esto podría deberse al punto de corte por categoría (AU)

Objective. To assess agreement in breast density classification using the BI-RADS® system and the concordance between this measurement method compared with a dedicated software program (Quantra®). Patients and methods. A descriptive study was carried out in 2 phases. First, we analyzed the BI-RADS® breast density classification assessed by 5 readers in a sample of 516 patients randomly selected and stratified into groups. Intraobserver and interobserver reproducibility were calculated (kappa index). Second, we evaluated the agreement between the most experienced reader and a software package that calculates the volumetric fraction of fibroglandular tissue (Quantra®). Results. The agreement between pairs ranged from fair to moderate (kappa 0.35-0.67). The reading group showed moderate reproducibility (0.58) with the highest values in high breast densities and in the youngest and oldest patients. Intraobserver agreement ranged from moderate to substantial (0.52-0.79). In density classification, there was no evidence of agreement between the expert reader and the software application (kappa = 0.0737). Conclusions. The agreement values obtained corroborate the evidence described in the literature on reading performed by experienced radiologists working exclusively with mammograms. No agreement was found in reader classification versus Quantra® (which classifies densities with a lesser percentage than visual analysis), which could be due to the cut off by category (AU)