Spontaneous mesenteric fibromatosis in Gardner's syndrome.

Mesenteric fibromatosis has been reported in frequent association with familial polyposis and with Gardner's syndrome. This vague "benign" process has been characterized as a postsurgical phenomenon with low morbidity. Two cases of spontaneous mesenteric fibromatosis, noted at the time of original laparotomy for colectomy in Gardner's syndrome patients, are reported. No history of abdominal trauma was present, and both have well-documented Gardner's findings. A 32% incidence of desmoid reaction is reported among affected members of the original Gardner's syndrome Kindred 109; five or 55% of these patients had the mesenteric form of the process. The potential fatal course of the mesenteric disease is emphasized.