ORIGINAL ARTICLE
INCIDENTAL RENAL CYSTS ON CHEST CT: A RETROSPECTIVE ANALYSIS OF PREVALENCE AND IMAGING CHARACTERISTICS

UDK: 616.61-006.2:[616.24-073.756.8:004

Dimitrijevikj K.

1University Clinic of Pulmonology and Allergology, Faculty of Medicine, Ss. Cyril and Methodius University in Skopje, North Macedonia

Abstract

Introduction: Chestcomputedtomography (CT) frequentlyincludesportionsoftheupperabdomen, allowingincidentalvisualizationofrenalstructures. Renalcystsareamongthemostcommonincidentalabdominalfindings.

Purpose:Todeterminetheprevalence, imagingcharacteristics, andclinicalsignificanceofincidentalrenalcystsdetectedduringroutinechest CT examinations.

MaterialandMethods:Thisretrospectivestudyreviewed 1,448 consecutiveadultchest CT examinationsperformedover a seven monthperiod from May-November 2025. Radiologyreportswerescreenedforrenalfindings, andimageswerere-evaluatedwhennecessary. RenalcystswerecategorizedusingtheBosniakclassification. Demographicdata andcystcharacteristicswererecorded. Descriptiveandcomparativestatistical analyses were conducted, andinterobserveragreementwasevaluatedusingCohen’skappa.

Results:Incidentalrenalcystswereidentifiedin 370 patients (25.6%). The prevalencewashigherinmenthaninwomen (30.6% vs 19.4%, p < 0.001). Thehighestnumberofcaseswere recordedinthe 45–65-year agegroup (54.6%). Cystswereunilateralin 63.8% andbilateralin 36.2% ofpatients. Corticalcystspredominated (52.2%), while 11.6% werecortico-medullary. Mildhydronephrosiswasfoundin 9.5% ofpatients. Mostpatients (55.4%) had a singlecyst. Interobserveragreementwassubstantial (κ = 0.66). Only 2,5 % of patients had cysts requiring follow-up (Bosniak II-III).

Conclusion:Incidentalrenalcystsarecommononchest CT andincreasewithage. Mostaresimple, unilateral, andbenign. Routinereportingofincidentalrenalcystsisrecommendedtoensureappropriatefollow-upwhenclinicallywarranted.

Keywords:Bosniakclassification; chest CT;incidentalfindings;renalcysts;prevalence.

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