Discordant Elastography Images of Breast Lesions: How Various Factors Lead to Discordant Findings

Abstract

Purpose: To evaluate the rate of the elastography-pathology discordance, and evaluate which various factors have an effect on discordant elastography images (DEI) of breast lesions.

Materials and Methods: Elastography images of 284 pathologically confirmed breast lesions of 233 patients were evaluated. Elasticity scores were compared to pathology results, and lesions were divided into 4 groups: benign concordant/discordant, and malignant concordant/discordant. The rate of DEI among benign and malignant lesions was calculated and compared. Patient, lesion factors and image adequacy were compared among the concordant and discordant groups for analysis.

Results: Among the 284 breast lesions, 225 (79.2 %) were benign, and 59 (20.8 %) were malignant. The rate of DEI among malignant lesions was significantly higher than in benign lesions, i. e., 52.5 vs. 3.1 % (p < 0.001). Discordant images were more significantly seen in patients with extremely dense breasts on mammography in benign lesions, 42.9 vs. 11.9 % (p = 0.034). Discordant images were more significantly seen in malignant lesions < 10 mm or ≥ 20 mm (p = 0.006), and those with inadequate images (64.5 vs. 35.5 %, p < 0.001).

Conclusion: The rate of DEI was higher in malignant lesions than in benign lesions. Dense breast parenchyma, lesion size and image adequacy showed significance in discordant images of elastography which need consideration in image acquisition and interpretation.

Zusammenfassung

Ziel: Die Rate der Nicht-Übereinstimmung von Elastografie und Pathologie zu ermitteln und auszuwerten, welche verschiedenen Faktoren einen Einfluss auf die diskordanten Elastografie-Bilder (DIE) von Brustläsionen haben.

Material und Methoden: Es wurden Elastografie-Bilder von 284 pathologischen bestätigten Brustläsionen von 233 Patientinnen untersucht. Die Elasticity-Scores wurden mit den pathologischen Ergebnissen verglichen und die Läsionen wurden in 4 Gruppen unterteilt: gutartig übereinstimmend/diskordant und bösartig übereinstimmend/diskordant. Die DIE-Rate der benignen und malignen Läsionen wurde errechnet und miteinander verglichen. Bei den übereinstimmenden/diskordanten Gruppen wurden Patientinnen, Läsionsfaktoren und die Bildgenauigkeit miteinander verglichen.

Ergebnisse: Von den 284 Brustläsionen waren 225 gutartig (79,2 %) und 59 (20,8 %) maligne. Die DIE-Rate bei den malignen Läsionen war mit 52,5 % signifikant höher als bei den gutartigen Läsionen mit 3,1 % (p < 0,001). Nicht übereinstimmende Bilder wurden signifikant häufiger mit 42,9 vs. 11,9 % (p = 0,034) bei Patientinnen mit gutartigen Läsionen beobachtet, die in der Mammografie extrem dichte Brüste aufwiesen. Diskordante Bilder wurden ebenfalls signifikant häufiger bei malignen Läsionen < 10 mm oder ≥ 20 mm (p = 0,006) beobachtet und in denen mit unzureichender Abbildung (64,5 vs. 35,5 %, p < 0,001).

Schlussfolgerung: Die DIE-Rate war bei malignen Läsionen höher als bei gutartigen. Bei diskordanten Bildern in der Elastografie sind die Dichte des Brustparenchyms, die Größe der Läsion und die Bildentsprechung von Bedeutung und sollten bei der Bildaufnahme und Interpretation berücksichtigt werden.

Key words

breast - ultrasound - neoplasms

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