Evaluation and Classification of Incidentally Detected Splenic Lesions Based on B-Mode and Contrast-Enhanced Ultrasound

Abstract

Purpose To evaluate B-mode ultrasound (B-US) and contrast-enhanced ultrasound (CEUS) patterns of focal splenic incidentalomas (FSIs), and to correlate ultrasound patterns with benignity and malignancy via histologic examination and/or the clinical course.

Materials and Methods Between 2004 and 2021, 139 consecutive patients with an FSI detected by B-US were investigated additionally with CEUS. On CEUS, the arterial enhancement (AE) of the FSI (hyperenhancement, isoenhancement, hypoenhancement, and absent enhancement) was analyzed. Subsequently, the malignancy rate according to different B-US echo patterns and CEUS perfusion patterns was determined.

Results The final diagnosis of FSI was malignant in 9/139 (6.5%) and benign in 130/139 (93.5%) cases. The hypoechoic and hyperechoic lesions on B-US with arterial hyperenhancement on CEUS and the echogenic cystic or complex lesions on B-US with predominantly absent enhancement on CEUS were benign in 54/54 (100%) cases. 6/37 (16.2%) hypoechoic lesions on B-US with arterial hypo-/isoenhancement on CEUS and 3/48 (6.3%) of hyperechoic lesions on B-US with an arterial hypo-/isoenhancement on CEUS were malignant.

Conclusion Based on these results, FSIs reveal different malignancy rates depending on the B-US und CEUS patterns, and classification according to these B-US and CEUS patterns may be helpful in further evaluation of an FSI.

Zusammenfassung

Hintergrund Evaluation von B-Mode-Ultraschall (B-US) und kontrastverstärktem Ultraschall (CEUS) von fokalen Milzinzidentalomen (FSI) und Korrelation der Ultraschallmuster mit der Dignität der Läsionen, gesichert durch histologische Untersuchung und/oder klinischen Verlauf.

Materialien und Methoden Zwischen 2004 und 2021 wurden 139 konsekutive Patienten mit einem durch B-US entdeckten FSI zusätzlich mit CEUS untersucht. Bei der CEUS wurde das arterielle Enhancement (AE) des FSI (Hyperenhancement, Isoenhancement, Hypoenhancement und fehlendes Enhancement) analysiert. Anschließend wurde die Malignitätsrate in Abhängigkeit von verschiedenen B-US-Echomustern und CEUS-Perfusionsmustern bestimmt.

Ergebnisse Die finale Diagnose zeigte maligne FSI in 9/139 (6,5%) der Fälle und benigne FSI in 130/139 (93,5%) der Fälle. Die im B-US echoreichen und echoarmen Läsionen und in der CEUS mit einem arteriellen Hyperenhancement sowie im B-US echogene, zystische oder komplexe Läsionen mit überwiegend fehlendem Enhancement in der CEUS waren zu 54/54 (100%) benigne. 6/37 (16,2%) der echoarmen Läsionen im B-US mit arteriellem Hypo-/Isoenhancement in der CEUS und 3/48 (6,3%) der echoreichen Läsionen im B-US mit arteriellem Hypo-/Isoenhancement in der CEUS waren maligne.

Schlussfolgerung FSI weisen je nach B-US- und CEUS-Muster unterschiedliche Malignitätsraten auf, und eine Klassifizierung anhand dieser Muster kann bei der weiteren Beurteilung eines FSI hilfreich sein.

Keywords

incidentaloma - methods & techniques - ultrasound - CEUS - diagnosis - splenic lesion

Publication History

Received: 04 October 2022

Accepted after revision: 13 December 2022

Article published online:
02 February 2023

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