[MRI findings of liver metastases from clear cell renal carcinoma and analysis of the impact of adjuvant therapy].

Abstract

To investigate the MRI features of liver metastases from clear cell renal cell carcinoma (ccRCC) and evaluate the impact of postoperative adjuvant therapy on MRI findings. This study retrospectively analyzed clinical, pathological data, and MRI findings of 20 ccRCC patients [mean age (62.1±11.9) years, 14 males (70%)] with liver metastases (71 lesions in total) treated at the First Medical Center of Chinese PLA General Hospital from January 2015 to April 2024. Patients were stratified into adjuvant therapy (39 lesions) and non-adjuvant therapy groups (32 lesions). Two abdominal radiologists jointly evaluated MRI features of liver metastases from ccRCC, including lesion location, size, margins, signal characteristics of plain scan and enhancement patterns. Intergroup comparisons were performed using χ² tests or independent sample t tests. On unenhanced MRI, liver metastases from ccRCC predominantly exhibited moderate hypointensity on T₁-weighted imaging (64/71, 90.1%) and moderate hyperintensity on T₂-weighted imaging (59/71, 83.1%). On diffusion-weighted imaging (DWI), lesions showed mild hyperintensity (42/71, 59.2%) or marked hyperintensity (29/71, 40.8%). Signal drop was observed in 45.1% (32/71) of lesions on out-of-phase images. On contrast-enhanced MRI, liver metastases from ccRCC predominantly demonstrated arterial-phase peripheral rim hyperenhancement (50/70, 71.4%) with persistent rim enhancement maintained in portal venous and delayed phases (37/70, 52.9%). The adjuvant therapy group demonstrated significantly higher rates of ill-defined margins, but lower proportions of marked DWI hyperintensity and arterial-phase rim enhancement compared to the non-adjuvant therapy group (all P<0.05). Liver metastases from ccRCC typically present as multiple round hepatic lesions with hyperintensity on DWI, signal drop on out-of-phase images, and persistent rim enhancement across arterial, portal venous, and delayed phases. Postoperative adjuvant therapy may lead to ill-defined margins, reduced diffusion restriction, and non-rim arterial enhancement patterns in liver metastases from ccRCC.