Distorsión de la arquitectura mamaria: la mejor forma de enfrentarla / Distorsion of breast architecture: the best way to confront it

Abstract: Objective. Assess the performance of digital 2D mammography and tomosynthesis in the characterisation of architectural breast distortion (ABD). Material and method. A retrospective study, approved by the Ethics Committee, was conducted on mammographic studies on cases with a diagnosis of ABD selected from August 2015-August 2016. Cases with imaging modalities available on PACS were included: digital mammography (2D), tomosynthesis (TS), ultrasound (US), magnetic resonance (MR), and with biopsy performed at our institution. ABD cases associated with micro-calcifications and post-surgical changes were excluded. Detection rates and imaging characteristics were analysed, as well as the histopathological concordance. Results. A total of 81 cases of ABD without microcalcifications were detected on the mammographs, but only 52 met the inclusion criteria. According to histopathology, 23 (44%) were malignant, 17 (33%) were benign, and 12 (23%) were high-risk lesions. All were detected by TS and US, and classified as suspicious lesions (BI-RADS 4 or 5). In 2D mammography, 24 cases (46%) were not seen and 8 (33%) of these were malignant. Malignant lesions showed dense centres in 87% of cases. The most frequent lesion on ultrasound was a hypoechogenic area (60%) in 86% of lesions with penetrating vessels. A total of 21 MRI were performed, with mass enhancement being identified in all of them. Conclusion. ABD is better displayed in TS than 2D mammography. Despite its characteristics, histological examination is essential (even when a radiolucent centre is observed). Focused US should be the next procedure to follow, since it allows to visualize the lesion to be visualised, and can direct the percutaneous biopsy in most cases.

Resumen: Objetivo. Determinar en qué método de imagen se logra visualizar y caracterizar mejor una distorsión de la arquitectura mamaria (DAM). Material y método. Estudio retrospectivo, aprobado por el Comité de Ética. Se seleccionaron los estudios mamográficos con diagnóstico de DAM en nuestro servicio entre agosto de 2015 y agosto de 2016. Se incluyeron casos estudiados con al menos 3 de las modalidades de imágenes disponibles en PACS: mamografía digital (2D), tomosíntesis (TS), ecografía (US), resonancia (RM) y que fueron biopsiados en nuestra institución. Se excluyeron casos de DAM asociadas con microcalcificaciones y cambios posquirúrgicos. Se evaluaron la tasa de detección, las características imagenológicas y la concordancia histopatológica. Resultados. En 15 meses se detectaron 81 casos de DAM en mamografía; de estos, 52 cumplieron con los criterios de inclusión. Según la histopatología, 23 (44%) resultaron malignas, 17 (33%) benignas y 12 (23%) lesiones de alto riesgo (LAR). Todas fueron detectadas por TS y US, clasificadas como lesiones sospechosas (BI-RADS 4 o 5). En mamografía 2D, 24 casos (46%) quedaron ocultos, y de estos, 8 (33%) resultaron malignos. Las lesiones malignas presentaron centro denso en el 87% de los casos. La lesión más frecuente en ecografía fue el área hipoecogénica (60%), en el 86% de las lesiones con vasos penetrantes. Se contó con 21 RM, identificándose captación tipo masa en las patologías malignas. Conclusión. La DAM es mejor visualizada en TS que en mamografía 2D. Pese a sus características, un estudio histológico es indispensable (incluso al observar un centro radiolúcido). El US dirigido es el paso a seguir, ya que permite visualizar la lesión y dirigir su biopsia percutánea en la mayoría de los casos.

Ultrasonographic Findings of Mammographic Architectural Distortion

PURPOSE: To review the sonographic findings of various diseases showing architectural distortion depicted under mammography. MATERIALS AND METHODS: We collected and reviewed architectural distortions observed under mammography at our health institution between 1 March 2004, and 28 February 2007. We collected 23 cases of sonographically-detected mammographic architectural distortions that confirmed lesions after surgical resection. The sonographic findings of mammographic architectural distortion were analyzed by use of the BI-RADS lexicon for shape, margin, lesion boundary, echo pattern, posterior acoustic feature and orientation. RESULTS: There were variable diseases that showed architectural distortion depicted under mammography. Fibrocystic disease was the most common presentation (n = 6), followed by adenosis (n = 2), stromal fibrosis (n = 2), radial scar (n = 3), usual ductal hyperplasia (n = 1), atypical ductal hyperplasia (n = 1) and mild fibrosis with microcalcification (n = 1). Malignant lesions such as ductal carcinoma in situ (DCIS) (n = 2), lobular carcinoma in situ (LCIS) (n = 2), invasive ductal carcinoma (n = 2) and invasive lobular carcinoma (n = 1) were observed. As ovserved by sonography, shape was divided as irregular (n = 22) and round (n = 1). Margin was divided as circumscribed (n = 1), indistinct (n = 7), angular (n = 1), microlobulated (n = 1) and sipculated (n = 13). Lesion boundary was divided as abrupt interface (n = 11) and echogenic halo (n = 12). Echo pattern was divided as hypoechoic (n = 20), anechoic (n = 1), hyperechoic (n = 1) and isoechoic (n = 1). Posterior acoustic feature was divided as posterior acoustic feature (n = 7), posterior acoustic shadow (n = 15) and complex posterior acoustic feature (n = 1). Orientation was divided as parallel (n = 12) and not parallel (n = 11). There were no differential sonographic findings between benign and malignant lesions. CONCLUSION: This study presented various sonographic findings of mammographic architectural distortion and that it is difficult to differentiate between benign and malignant lesions depicted under sonography. Pathological confirmation is needed for mammographic architectural distortion.