Retroperitoneal leiomyosarcoma and gastroparesis: a new association and review of tumor-associated intestinal pseudo-obstruction.

Intestinal pseudo-obstruction has been associated with several types of underlying neoplasms and has been hypothesized to result from a paraneoplastic process in patients with small cell lung carcinoma and bronchial carcinoid. This article documents the first reported association of gastroparesis and a retroperitoneal leiomyosarcoma. A paraneoplastic process is the proposed basis of this relationship, inasmuch as these syndromes have been noted in other tumors of mesodermal origin. The resolution of intestinal dysmotility after tumor resection, as described here, has only rarely been reported.