Breast cancer and retroperitoneal metastasis.

Retroperitoneal fibrosis is an uncommon disease of diverse etiology. Carcinoma of the breast is rarely considered as a cause of retroperitoneal metastasis or fibrosis. This paper describes five patients with retroperitoneal fibrosis secondary to breast cancer. The mean duration from initial diagnosis to onset of symptoms was greater than ten years. The patients had received a variety of treatments for breast carcinoma and had extensive metastatic disease. Presenting symptoms included abdominal, flank, or low back pain. Two had small bowel obstruction and four had ureteral obstruction. It is possible that with long-term survival this complication may be seen more frequently.