Paraneoplastic Hypoglycaemia: A Rare Manifestation of Pelvic Gastrointestinal Stromal Tumour.

Non-Islet Cell Tumour Induced Hypoglycaemia (NICTH), presenting with recurrent fasting hypoglycaemia is a very rare paraneoplastic syndrome. It usually presents with large metastatic mesenchymal tumours. NICTH secondary to Gastrointestinal Stromal Tumour (GIST) is even rarer. Diagnosis of NICTH is based on the low serum insulin level, low serum concentrations of Insulin Like Growth Factor (IGF-I) and IGF binding protein- III (IGFBP-III) in combination with elevated concentrations of pro-IGF-II. Various Immunohistochemical (IHC) markers are integral to diagnosis of GIST namely 2-deoxyglucose-6-phosphate phosphatase -1(DOG-1), Cluster Differentiation 34 (CD 34), Cluster Differentiation 117 (CD117). The management requires prompt intravenous hydration and glucose infusions followed by surgical resection. We hereby, report a rare case of a 65-year-old female with intractable fasting hypoglycaemia due to overproduction of "big" insulin-like growth factor II diagnosed to have pelvic GIST and managed by Steroids and Imatinib.