Fig. 3

A 36-year-old man with PCV unicentric Castleman disease. T1-weighted image (a) and T2-weighted image (b) show a mass (*) in the retroperitoneum, well-defined, homogeneous, hypointense on T1, hyperintense on T2 as well as on diffusion-weighted imaging (DWI) b = 600(c). After gadolinium contrast injection in the arterial phase (d), lesion is hyperintense, followed by sustained hyperintensity in portovenous phase (e). Photomicrograph (f, original magnification, × 200; hematoxylin-eosin [H-E] stain) shows diffuse plasma cell proliferations in the interfollicular tissue. (UCD = unicentric Castleman disease; MCD = multicentric Castleman disease; HVV = Hyaline vascular variant; PCV = Plasma cell variant)