Endocrine Abstracts

A 58-year-old female presented to Urology clinic after an abdominal ultrasound revealed a right sided mass. She had a 9 year history of hypertension which had been difficult to control despite treatment with six agents. She also had a history of Type 2 Diabetes Mellitus and Hyperlipidaemia. CT Thorax/Abdomen/Pelvis reported a 20 cm right renal mass with areas of calcification and following MDT discussion the diagnosis of renal cell carcinoma was made. An open right radical nephro-adrenalectomy was performed with no reported intra-operative complications. However, her post-operative period was complicated by recurrent episodes of hypotension and acute kidney injury. She received multiple courses of antibiotics and required two admissions to Critical Care. She developed type 2 respiratory failure secondary to fluid overload and had a brief spell of non-invasive ventilation. Echocardiogram revealed a new regional wall motion abnormality suggesting a perioperative myocardial infarction. Her hypotension episodes continued despite stopping her antihypertensives and she also developed hypoglycaemia. Morning cortisol was 170 nmol/l, prompting the initiation of Hydrocortisone. She was eventually discharged after 48 days and subsequent dynamic testing demonstrated a profoundly inadequate response to Synacthen stimulation. Histological analysis of the extracted mass reported a normal kidney and adrenal gland within a malignant neuroendocrine carcinoma. This stained strongly with synaptophysin and negatively for chromogranin A, however the presence of vasoactive amines suggested it had arisen from a pre-existing functioning phaeochromocytoma. Functional imaging after discharge showed no evidence of active disease or metastasis. We present this rare and fascinating case of a malignant neuroendocrine tumour encapsulating a normal kidney and adrenal gland that was originally diagnosed as a renal cell carcinoma. It is likely the sudden reduction in circulating catecholamines following tumour excision significantly contributed to her unstable post-operative period and resultant prolonged admission. Her pre-existing hypertension and Type 2 diabetes have now resolved and she remains off the medications. This case raises the question of whether patients with a renal mass in the context of resistant hypertension should be screened for phaeochromocytoma during their pre-operative assessment.