The European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) has recently published in the European Journal Ultrasound, the most prestigious ultrasound journal, the Consensus of experts on revisiting the classification of renal cysts by contrast-enhanced ultrasound, coordinated by Vito Cantisani, Vice Dean of the Faculty of Medicine and Dentistry of Sapienza University.

The recently published Consensus has clarified the recommendations for using the various methods of classifying renal cysts, analysing their advantages and providing guidance on their use. 

"The diagnosis of renal cyst, says Cantisani, is one of the most common diagnoses in the general population, especially in old age.  For the patient, this diagnosis creates apprehension and concern".

In most cases, renal cysts have no clinical significance and do not require further investigation or treatment.  Moreover, they are often encountered by chance, as they are completely asymptomatic. However, in about 8% of cases, renal cysts may be associated with non-specific symptoms such as flank pain, hypertension, haematuria and sometimes fever due to over-infection. In a small percentage of cases, the kidney cyst may be malignant and require surgery. More advanced instrumental examinations, such as computed tomography, magnetic resonance imaging or ultrasound with contrast medium, are required in these cases.

The Consensus of the experts resulted in a new classification of cysts using contrast-enhanced ultrasound alone - CEUS: Contrast-Enhanced UltraSound - which has the advantage that it does not use ionising radiation; furthermore, it is very well accepted by patients and can be used in subjects with renal function problems.

CEUS combines the non-invasiveness and high spatial resolution of ultrasound with the vascular and tissue information of intravenous contrast medium. In particular, it focuses on the peripheral thickness of the cyst, the presence, number and thickness of the internal septa and the possible presence of solid intra-cystic nodular formations, which, if present, increase the risk of malignancy of the cyst, thus indicating the need for therapeutic-surgical treatment or re-evaluation over time. Systematic use of CEUS could reduce the use of 'heavy' methods, allowing patients to have frequent, minimally invasive check-ups to reassure them about their health, with clear benefits for the NHS.

References:

EFSUMB 2020 Proposal for a Contrast-Enhanced Ultrasound-Adapted Bosniak Cyst Categorization - Position Statement - Vito Cantisani, Michele Bertolotto, Dirk-André Clevert, Jean-Michel Correas, Francesco Maria Drudi , Thomas Fischer, Odd Helge Gilja, Antonio Granata, Ole Graumann , Christopher J Harvey , Andre Ignee, Christian Jenssen , Markus Herbert Lerchbaumer, Matthew Ragel, Adrian Saftoiu , Andreas L Serra , Konrad Friedrich Stock , Jolanta Webb, Paul S Sidhu -  Ultraschall Med. 2021 doi: 10.1055/a-1300-1727