The Sonographic Characteristics of Unicentric Castleman Disease - a single-center Retrospective Study

Background Unicentric Castleman disease (UCD) is a rare group of non-neoplastic lymphoproliferative disorders. This study aims to summarize the specific ultrasonic manifestations of UCD. Methods This retrospective study included patients who underwent preoperative ultrasound for enlarged lymph nodes and were later diagnosed with UCD between January 2016 and March 2024. Ultrasound features, including lymph node size, cortical characteristics, corticomedullary interface, hyperechoic regions, and Doppler flow signals, were recorded. Pathological types were classified as hyaline vascular (HV), plasma cell (PC), or mixed. The ultrasonic features of each UCD subtype were systematically analyzed. Results A total of 41 patients were enrolled, including 29 patients with HV-type, 4 with PC-type and 8 with mixed type. All patients exhibited enlarged LNs characterized by solitary mass, well-defined margins and increased cortical thickness. Among them, 95.12% (39/41) of cases had an indistinct corticomedullary interface. 41.46% (17/41) showed eccentric or asymmetrical cortical thickening, and 58.54% (24/41) demonstrated complete effacement of the fatty hilum. About 24.39% (10/41) of cases exhibited macrocalcification, and 56.10% (23/41) displayed short linear hyperechoic foci within the LNs. Additionally, HV-type and mixed-type patients had more abundant blood flow signals than PC-type patients (75.86% vs 25% vs 87.50%, P = 0.018). Conclusions Ultrasound features of UCD typically include large, solitary masses with well-defined margins, a thickened cortex, and loss of the fatty hilum. Key imaging findings are micro-calcifications and short linear hyper echoes. Ultrasound is an effective and non-invasive tool for the early detection and diagnosis of UCD. Trial registration retrospectively registered.