Complete Large Bowel Obstruction by a Rare Pelvic Mass

Summary

A 59 years old male patient presented with 4 days history of colicky abdominal pain and distension, nausea, vomiting with absolute constipation. Plain abdominal X-ray showed greatly distended colon with air-fluid levels. Abdominal CT-scan revieled complete large bowel obstruction due to external compression and complete occlusion of the rectum by a big well circumscribed mass in the presacral region, occupying the whole true pelvis. The patient underwent emergency laparotomy and a left loop colostomy to relieve the obstruction. Subsequent MRI study revealed a well encapsulated deep supralevator pelvic mass filling the presacral concavity of 13 x10 x 8 cm, causing complete collapse and obstruction of the rectum. The radiologic features suggested a GIST or mesenchymal tumour. During laparotomy, the mass was snuggly filling the true pelvis and was not possible to deliver either from the perineum or the abdominal. After several attempts, it was delivered intact transabdominally by a using baby “delivery forceps”. The patient had an uneventful recovery and his colostomy was later closed. Histopathology showed benign retroperitoneal fibromatosis. In the presence of complete bowel obstruction, the priority in management is first to vent the bowel and relieve the obstruction. Following that, the obstructed mass should be investigated and later excised. Much pathology can present as solid presacral masses like lipoma/liposarcoma, leiomyoma/leiomyosarcoma, fibroma/fibrosarcoma, Desmoid tumors, ganglioneuromas, paragangliomas, and lymphoma. Preoperative diagnosis may be possible by fine needle aspiration cytology or core biopsy.