Waldenström Macroglobulinemia Diagnosed by Ultrasonography-Guided Biopsy of the Right Perinephric Tumor. - Morinaga S; Aoki S; Tobiume M; Nishikawa G; Higuchi F; Ikenohata Y; Honda M; Kubo H; Sawada T; Yamada Y (IJU case reports, 2025)