Utility of Salivary Cortisol in the Management of Adrenal Incidentaloma Patients with Subclinical Cushing’s Syndrome

Presentation Number: SUN 401
Date of Presentation: April 2nd, 2017

Feaz Babwah*1, Sushuma Kalidindi1, Arun M A Vijay1, Julian Waldron1, Cherian George1, Anurag Golash2, Gill Powner3, Jessica Hawarden1, Anthony A Fryer4 and Fahmy WF Hanna1
1University Hospitals of North Midlands NHS Trust, United Kingdom, 2University Hospital of North Midlands, 3UHNM, 4University Hospitals of North Midlands NHS Trust, Stoke-on-Trent, United Kingdom

Abstract

INTRODUCTION

Salivary cortisol in an increasingly popular and novel investigative tool in the work-up of patients with adrenal incidentalomas (AI). Subclinical Cushing’s Syndrome (SCS) is a common feature in such patients and its natural history is unknown. While these patients are asymptomatic, there is good evidence that mild autonomous cortisol production in the long term has a significant impact on cardiovascular and bone health1.

METHODS

We analyzed 200 consecutive patients with AI over a two year period (2014 - 2016). The overnight dexamethasone suppression test (ODST) was used as the initial screening test. Those whose cortisol levels failed to suppress to ≤ 50 nmol/l (as proposed in the new European Guidelines2) went on to have a low dose dexamethasone suppression test (LDDST) with paired urinary free cortisol (UFC) collections. Salivary cortisol sampling was performed in those who failed to suppress on LDDST.

RESULTS 

Of this cohort of unselected AI patients (n=200) the mean age was 66.35 ± 12.23 years (± SD), with a male:female ratio of 2:3. Out of the total lesions identified (n=236), 15% were bilateral and 59% were left-sided. The majority (70.3%) of lesions were classed as lipid rich adenomas based on imaging criteria (Hounsfield units <10 or ≥ 50% washout) while 23.7% were indeterminate. A small number of lesions (6.5%) were found to be > 4cm in size. 52.8% of patients (n=104) failed to suppress on ODST. 94 patients proceeded to LDDST with 66% of them (n=62) failing to suppress. This group was therefore defined as having SCS. Out of these, 52 patients had salivary cortisol studies performed with 24 patients (46.2%) having preserved diurnal rhythm (defined as a 2300 hr salivary cortisol value of ≤ 3.2 nmol/l on each day sampled). Of this SCS group, 61.3% of patients had hypertension and 27.4% had diabetes.

Adrenalectomy was performed on 6 patients, with a further 2 patients on the waiting list for surgery. 4 patients of this surgical group had salivary cortisol sampling performed for SCS, all of which demonstrated loss of diurnal rhythm. There was histological confirmation of adrenal cortical neoplasm in 5 cases (1 patient had a phaeochromocytoma). All 5 patients required steroid replacement postoperatively, thus confirming autonomous cortisol secretion.

CONCLUSION 

  • SCS is the most common endocrine abnormality in patients with AI. Emerging evidence indicate they are not as benign as once thought1
  • This case series outlines the impact of adopting the new guidance2 and its consequences for subsequent assessment in a real world setting. 
  • Preserved diurnal rhythm (using salivary cortisol) in patients with SCS may provide a level of reassurance and support a conservative approach.
  • When compared to the LDDST and UFC tests, both of which are cumbersome and labour intensive, salivary cortisol sampling provides a convenient and practical alternative. 

 

Nothing to Disclose: FB, SK, AMAV, JW, CG, AG, GP, JH, AAF, FWH