Endocrine Abstracts

Introduction: We describe a case of a 32 year old woman with bilateral carotid body tumours as initial finding of a paraganglioma syndrome type 1.

Case: A 32-year old previously healthy mother was referred because of bilateral neck swelling, presumably lymphadenopathy, associated with recurrent upper respiratory tract infections during the past year. Cervical ultrasound raised the suspicion for bilateral carotid body tumours which were confirmed by MR-imaging and a subsequent DOPA-PET-CT, which showed no evidence for multifocality or metastases. Plasma metanephrines including methoxytyramine were within the normal range and although a family history was negative, the genetic work-up revealed a SDHD mutation (paraganglioma syndrome typ 1). Because of mass effects and the patients wish, resection of the right sided tumour has been scheduled.

Discussion:: HNPGLs are rare tumours (incidence 1:30 000 – 100 000) derived from extraadrenal chromaffin cells and 95% arise from the parasympathic nervous system, typically the carotid body (glomus caroticum), jugular bulb (glomus jugulare) and different branches of the vagal nerve (glomus vagale, glomus typanicum). Plasma methoxytyramine may be elevated (1/3 of cases), normally they are clinically nonsecretory and present because of their mass effects. Around 35% are associated with a genetic defect, with SDHD-mutations accounting for >50%, SDHB for 20–35% and SDHC for 15% (extraordinary SDHAF2). The inheritance pattern is autosomal dominant for SDHx mutations, but in SDHD and SDHAF2 maternal imprinting is postulated. Malignancy is rare (3.5%) although metastases occur up to 20 years after initial diagnosis. Staging is performed by functional imaging with ¹⁸F-DOPA- or ⁶⁸Ga-DOTATATE-PET-CT, anatomical imaging with CT and/or MRI gives a better locoregional resolution. Surgical resection may be associated with significant morbidity especially caudal cranial nerve injury. Radionuclid-therapy or radiotherapy/-surgery must be evaluated as alternatives. Genetic counselling and testing is mandatory due to the high rate of germline mutations and familial disease.