AB186. 148. Concomitant primary leiomyosarcoma of jejunum and renal oncocytoma: a case report and literature review

Abstract: Leiomyosarcoma of small bowel is quite rare, comprising 2–3% of all small bowel tumours. It usually presents with non-specific symptoms and early recognition is crucial. Here we report a case of jejunal leiomyosarcoma with concurrent renal oncocytoma and review of the literature. A 51-year-old gentleman presented to emergency department with abdominal pain and right sided abdominal tenderness, with no associated systemic features. After initial workup, CT scan of abdomen and pelvis that showed a 12-cm mass in the right abdomen, and an incidental 5 cm left renal mass. After multi-disciplinary discussion, he underwent laparotomy and en bloc resection of jejunal mass with primary anastomosis, and left nephrectomy. Histology revealed an intermediate grade leiomyosarcoma with clear margins and confirmatory immunohistochemistry. Renal mass was an oncocytoma. No evidence of distant metastases was found on CT scanning. Patient recovered fully. Multi-disciplinary team recommended 6 monthly imaging follow-up and no adjuvant treatment. Leiomyosarcoma of small bowel are quite rare with only 26 cases reported between 2000 and 2012. Only after the advent of novel immunohistochemical techniques in late 1990s, their differentiation form gastrointestinal stromal tumours (GISTs) became possible. Also no case of a co-existing renal oncocytoma has been reported to date. Oncocytoma is benign and surgical resection is curative. National Comprehensive Cancer Network (NCCN) guidelines recommend complete oncological resection, intense follow-up and selective use of adjuvant chemo-radiation. The management of small bowel leiomyosarcoma is centred on surgical resection with adjuvant treatment in selected cases and requires regular follow up. Tumour grade and extent of surgical resection are main predictors of prognosis.

Keywords: Leiomyosarcoma; oncocytoma; small bowel