Retroperitoneal Fibrosis Confined to the Pelvic Cavity

Aim: To find whether there were characteristic clinical or imaging findings in retroperitoneal fibrosis (RPF) confined in the pelvic cavity. Methods: Literature review was performed using MEDLINE with key words of [retroperitoneal fibrosis and pelvis] and [pelvic fibrosis]. Results: In addition to our 68-year-old Japanese woman, 13 cases were found, in which computed tomography (CT) or magnetic resonance imaging (MRI) confirmed that the mass lesions were confined in the pelvic cavity. The pelvic RPF (age range, 29-69 y.o. ; seven male) showed variable symptoms and clinical presentation suggestive of gynecological, urological or colonic diseases. CT usually revealed an ill-defined well-enhanced mass lesion, which may be associated with fascial thickening. On MRI the pelvic masses showed low signal intensity on T1-weighted images and high or mixed signal on T2-weighted images. In nine of 14 patients the presacral or retrorectal spaces were involved, and the remaining patients had RPF around the bladder. In seven patients, imaging-guided needle biopsies were employed. Good prognoses were reported in all 11 patients, in which corticosteroid therapy were given. Conclusion: Pelvic RPF may show different symptoms and clinical features from typical paraaortic RPF, but shows similar imaging findings. The imaging-guided biopsy is the choice for histopathological diagnosis