Contrast-enhanced mammography and preoperative magnetic seed placement in breast cancer patients for the detection of residual disease following neoadjuvant systemic therapy

Abstract

Purpose

Assess whether contrast-enhanced mammography (CEM) enables an evaluation of the residual size of breast tumours following neoadjuvant systemic therapy (NAST) in patients initially marked with magnetic seed.

Materials and methods

This single-centre prospective study was performed between March 2022 and April 2023 with patients with invasive breast carcinoma and lesional marking with magnetic seed. CEM was performed before and after NAST. The lesion size in CEM after NAST was compared to the pathological examination after surgery. Differences between sizes were evaluated and we determined the diagnostic capability indices.

Results

The breast lesions marked with magnetic seed were successfully localised in the preoperative stage for the 42 patients included in the study and selective surgical excision was also achieved in all cases. Tumour diameter after NAST was determined by comparing enhancement on combined CEM images from before and after NAST. The mean diameter was 13.6 mm while post-surgical pathological examination determined the mean diameter to be 12.9 mm. There were therefore no statistically significant differences between the measurements.

Conclusions

There is a positive correlation and similarity between CEM and pathological examination with regards to the detection of residual disease after NAST, with high specificity and PPV.

Resumen

Objetivo

Valorar si la mamografía con contraste (MC) permite evaluar el tamaño tumoral residual en la mama tras realizar tratamiento sistémico neoadyuvante (TSN) en pacientes con cáncer de mama, marcado inicialmente con semilla magnética.

Materiales y métodos

Se realizó un estudio prospectivo unicéntrico entre marzo 2022 - abril 2023 con pacientes con cáncer de mama infiltrante y marcaje lesional con semilla; se realizó MC antes y después del TSN. Se comparó el tamaño lesional en MC posterior al TSN respecto al de la valoración anatomopatológica tras cirugía, se evaluaron las diferencias de los tamaños y se determinaron los índices de capacidad diagnóstica.

Resultados

En las 42 pacientes incluidas se consiguió con éxito la localización preoperatoria y la exéresis quirúrgica selectiva de las lesiones mamarias marcadas con semilla magnética. La media del diámetro mayor tumoral tras TSN, determinado por el realce en las imágenes recombinadas de la MC, fue de 13,6 mm vs 12,9 mm en el examen patológico postquirúrgico, no hallándose diferencias estadísticamente significativas entre las medias de las mediciones.

Conclusiones

La MC presenta una buena correlación y concordancia con la histopatología para detectar la enfermedad residual tras TSN, con elevada especificidad y VPP.