Case report: Radiolabelled octreotide scanning as a guide to the management of an occult carcinoid tumour

Abstract

Non-gastrointestinal primary carcinoid tumours can be difficult to localize using conventional imaging techniques. We report a case of an ovarian carcinoid not appreciated on pelvic ultrasound which was identified and shown to be localized to the pelvis by 111indium labelled octreotide scanning. At surgery the tumour was confirmed to be localized to the area identified by the scan. One year post surgery, the patient remains asymptomatic and disease free. CASE REPORT A 56-year-old nurse was referred with a I-year history of episodic breathlessness and wheeze. Her symptoms had persisted despite treatment with inhaled corticosteroids, salbutamol and oral aminophylline. She had never smoked and there was no history of atopy. One week prior to assessment she had noticed ankle oedema. On direct questioning she had experienced facial flushing, particularly after ingestion of alcohol and six months of intermittently loose stools. Eighteen months previously she had undergone a pelvic ultrasound examination for postmenopausal bleeding which suggested a fibroid uterus, and had a D & C which produced an endocervical polyp. On examination she had a reddish purple facial hue. Jugular venous pressure was elevated and auscultation of her heart revealed a systolic tricuspid murmur and a right ventricular gallop rhythm. Scattered polyphonic wheezes were heard throughout both lung fields. Her liver was not palpable and there was no evidence of ascites or peripheral oedema. Her fibroid uterus was easily palpable. Initial investigations revealed a raised urinary 5HIAA at 666/~mol/1 (normal range 9-30). Spirometry was mildly abnormal; FEVI 2.051 (2.9), FVC 3.41 (3.4), there was less than 5% improvement after inhaled salbutamol. Transoesophageal echocardiogram showed a thickened septal cusp of the tricuspid valve, tricuspid regurgitation and a dilated right ventricle with impaired function. The pulmonary valve was normal. In order to locate the source of production of the 5HIAA, ultrasound and liver computed tomography (CT) were performed, both of which were normal. ACT of the thorax was also normal. Ultrasound scan of the pelvis showed a large fibroid uterus, and a mass was seen posteriorly which was thought to represent a pedunculated fibroid. The ovaries were difficult to visualize. Unfortunately images of this examination are not available. At this stage 1 llindium lal~elled octreotide scanning was performed to attempt localization and staging of the carcinoid tumour. One hundred and ten MBq of 1 l~indium labelled octreotide (Octreoscan-Mallinckrodt Ltd, Northampton, UK) was given intravenously. Gamma camera images were obtained post injection. An area of increased uptake was visualized in the pelvic region at 4, 24 and 48 h which persisted post bladder catheterization (Fig. 1). One month later, under octreotide cover, a laparotomy was performed. A large ovarian mass and a bulky uterus were found. The bowel and liver appeared normal. Total abdominal hysterectomy, bilateral salpingooophorectomy, appendicectomy and mesenteric node biopsy were performed without complication. Histological analysis revealed a right ovarian carcinoid tumour and a uterine fibromyoma. The regional lymph nodes and omentum were free of tumour. The urinary 5HIAA concentration was normal three days after surgery. One year later she remains well and her urinary 5HIAA is in the normal range. Interestingly her wheeze, though improved, has persisted and she requires regular inhaled corticosteroids and periodic beta-agonists. A repeat DISCUSSION