Tamoxifen monotherapy in the treatment of retroperitoneal fibrosis.

OBJECTIVE To evaluate the therapeutic effect of tamoxifen monotherapy in patients with retroperitoneal fibrosis (RPF). PATIENTS AND METHODS From 2007 on, 31 patients with idiopathic RPF were treated with tamoxifen monotherapy. Follow-up investigations included magnetic resonance imaging, laboratory measurements, registration of side effects and changes or removal of ureteral stents. Data were stored in the Else Kröner-Fresenius Registry of Retroperitoneal Fibrosis. RESULTS 25 men and 6 women with a mean age of 56.6 years were treated with tamoxifen monotherapy. Mean duration of treatment was 13.3 months, mean follow-up 26.8 months. A total of 44 renal units were affected by hydronephrosis and covered by DJ stents. Radiological regression of fibrosis was detected in 22 cases (71.0%); removal of ureteral stents was possible in 27/44 renal units (61.4%) and 17/29 patients (58.6%), respectively. Most patients showed only mild or no side effects of therapy. In 7 cases (22.3%) tamoxifen therapy had to be abandoned because of severe side effects, progression of fibrosis or persistent intolerance. CONCLUSIONS Tamoxifen is an alternative in the medical treatment of RPF, especially if patients want to avoid glucocorticoids. The potential of regression of fibrosis seems to be slightly inferior and the relapse rate is higher compared to steroids, but the rate of successful DJ removals is comparable.