[Giant ectopic peritoneal and omental deciduosis mimicking a peritoneal carcinomatosis]

Ectopic decidual reaction of the peritoneum and the omentum is rare. It is usually an incidental finding during caesarean section and it could mimick macroscopically peritoneal carcinomatosis or tuberculosis. Histology is very important to make diagnosis. Ectopic decidual reaction is physiological, with an excellent prognosis and spontaneous resolution. We report one case of ectopic peritoneal and omental deciduosis of the peritoneum and discovered incidently during caesarian section. Definitive diagnosis was done by immunohistological examination. A laparoscopy four months later showed complete and spontaneous regression of all lesions.