ESA-SRB-AOTA 2019

Metastatic paraganglioma in an SDHB mutation positive patient (#651)

Jasmine J Zhu 1 , John R Burgess 1 2
  1. Department of Endocrinology, Royal Hobart Hospital, Hobart, TAS
  2. School of Medicine, University of Tasmania, Hobart, TAS

Paragangliomas are rare neoplasms arising from pluripotent neural crest cells in the autonomic nervous system.  They may secrete catecholamines, leading to flushing and hypertensive crises.  Although resection is recommended as first-line treatment for localised disease, peptide receptor radioligand therapy (PRRT) is effective and well-tolerated for disseminated disease that expresses somatostatin receptors.   A unique feature of paragangliomas is their slow and minimal response to PRRT, radiotherapy and somatostatin analogues.  Even when successfully treated, they often demonstrate a residual mass, the presence of which does not necessarily indicate treatment failure.  We report a case of metastatic paraganglioma in an SDHB mutation positive patient who was successfully treated with PRRT.  A 12-year-old male experienced a hypertensive crisis during routine anaesthetic induction for an elective procedure.  After α followed by β blockade, an extra-adrenal secretory paraganglioma was resected.  He was subsequently found to be SDHB-mutation positive.  At the age of 15, he underwent re-resection of locally recurrent disease.  Due to a progressively rising chromogranin A, an FDG-PET scan was performed at the age of 22.  This showed retroperitoneal soft tissue disease and widespread skeletal metastases. These lesions were avid on a GATATE PET scan but not on a MIBG scan. Retrospective review of MRI images from the previous year revealed that one of the bony lesions had already been present on this scan and had not changed in size.  In combination, these imaging findings suggested slowly progressive disease with high somatostatin receptor expression.  The patient was treated with three cycles of PRRT combined with 5-FU as a radiosensitising agent, which was well tolerated.  Serial imaging over a five-year period has demonstrated stable lesions.  He is currently being managed with somatostatin analogues.  This case illustrates the role of different imaging modalities in the evaluation of neuroendocrine tumours and the complexities of managing disseminated disease.