High rates of the SDHB p.Arg46Gln pathogenic variant predisposes New Zealand Māori to phaeochromocytoma/paraganglioma

Intern Med J. 2023 Oct;53(10):1883-1889. doi: 10.1111/imj.15965. Epub 2022 Nov 19.

Abstract

Background: Phaeochromocytomas (PCC) and paragangliomas (PGL; together PPGL) are rare tumours of the adrenal medulla or extra-adrenal paraganglia. They may secrete catecholamines with significant cardiovascular effects. Management of PPGL is predominantly surgical, despite the anaesthetic risks related to potential haemodynamic instability. Meticulous pre-treatment and intra-operative management are required to improve cardiovascular outcomes.

Aims: There are limited local data regarding the incidence of PPGL and the clinical characteristics of individuals diagnosed with these tumours in New Zealand. We undertook a retrospective study investigating the local practice and patient characteristics with an additional focus on intra-operative haemodynamic stability and post-operative outcomes.

Methods: Electronic patient records were searched for individuals with a diagnosis of PPGL. Clinical records and electronic databases were interrogated for pre-operative, intra-operative and post-operative data points. Particular attention was paid to rates and types of germline mutations, intra-operative haemodynamic stability and post-operative renal and cardiovascular outcomes.

Results: We identified 49 individuals with PPGL, of whom 34 were from the local area. This gave a local incidence of PPGL of around five cases per million people per year. Māori were significantly over-represented in our cohort, with this being in part due to high rates of the SDHB R46Q mutation. Over 95% of our cohort met pre-specified pre-operative blood pressure parameters. Intra-operative monitoring revealed a tendency to hypotension, but this did not translate into adverse post-operative outcomes, which were infrequent.

Conclusions: Māori were over-represented due to high rates of germline SDHB R46Q mutations. There were few post-operative adverse outcomes in this contemporary cohort.

Keywords: anaesthesia; haemodynamics; mutation; paraganglioma; phaeochromocytoma.

MeSH terms

  • Adrenal Gland Neoplasms* / diagnosis
  • Adrenal Gland Neoplasms* / genetics
  • Adrenal Gland Neoplasms* / surgery
  • Germ-Line Mutation
  • Humans
  • Maori People
  • New Zealand / epidemiology
  • Paraganglioma* / genetics
  • Paraganglioma* / surgery
  • Pheochromocytoma* / genetics
  • Pheochromocytoma* / surgery
  • Retrospective Studies
  • Succinate Dehydrogenase / genetics

Substances

  • Succinate Dehydrogenase
  • SDHB protein, human