eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2016-12-21 4 12 371 375 10.12691/ajmcr-4-12-1 AJMCR20164121 article Jhon Paul Castillo León jhon_934@hotmail.com 1 Mario Montalvo Burbano 2 María del Cisne Ordoñez Izquierdo jhon_934@hotmail.com 3 General Surgeon, Department of General Surgery of Metropolitan Hospital, Quito, Ecuador Surgical Oncologist and General Surgeon, General Surgery Department of Metropolitan Hospital, Quito, Ecuador General Medical, Isidro Ayora Hospital, Loja, Ecuador The objective of this article is to present a rare case such as peritoneal inclusion cyst or a benign cyst mesothelioma, a rare injury that predominantly affects women of reproductive age, with a still unknown etiology. Materials and Methods: We present the clinical case of a 36-year-old women, asymptomatic, with a pelvic ultrasound reported free abdominal fluid in a medical checkup. In her medical history revealed that six years ago the patient underwent laparotomy for complicated appendicitis with peritonitis. The abdominal and pelvic scan showed a giant cystic lesion of 20 cm x 17 cm x 10 cm, which occupies part of the abdomen and pelvis. Result: surgical treatment was decided and the patient underwent laparotomy, achieving the complete elimination of cystic mass and small bowel resection joined the cyst was performed. The histopathology report confirmed the diagnosis of peritoneal inclusion cyst. Conclusion: location, type of injury and behavior of mesothelioma cysts should be considered as they have a high recurrence rate and are often asymptomatic. http://pubs.sciepub.com/ajmcr/4/12/1/ajmcr-4-12-1.pdf peritoneal inclusion cyst benign cystic mesothelioma laparotomy