Huge Perineal Tumour: A Rare Presentation of Gastrointestinal Stromal Tumour of Rectum.

Gastrointestinal stromal tumour (GIST) is a relatively rare neoplasm of gastrointestinal tract of which Rectal GIST is uncommon. It produces symptoms of per rectal bleeding or change in bowel habit. Recurrences following curative resection are predominantly intraabdominal, hepatic metastasis occurring at a median 20-25 months following the primary surgery. A 42 years old male presented a huge mass in hypogastrium, the size of which was reduced ofter neoadjuvant therapy for period of 1.5 years. He underwent abdominoperineal resection. He developed recurrences in perineum three times and in thigh at short intervals after primary resection. He also developed liver metastasis. He died two and half years after primary diagnosis. Rectal GIST should be included in differential diagnosis of intraabdominal mass and preoperative diagnosis based on histopathological as well as the immunohistochemical feature of the CD(117) and CD(34). Although complete surgical resection with negative tumour margin is the principal curative procedure for primary and non metastatic tumours, further studies are still needed for the determination of the most effective treatment strategy for patients of rectal GIST.