Adrenal Incidentaloma: Evidence Based Approach Dr Daniel Wong Department of Surgery Kwong Wah Hospital

Adrenal Incidentaloma- Definition Adrenal mass >1cm Detected during investigation for extra-adrenal pathology Exclude workup of Known malignancy patients Hypertensive and hypokalaemic patients

Adrenal Incidentaloma- Definition Prevalence 1.4-8.7% Found in up to 5% CT scan Angeli Horm Res 1997 Barzon et al Eur J Endocrinol 2003

Adrenal Incidentaloma- Aetiology Adrenal cortical tumours Adenoma, nodular hyperplasia, carcinoma Adrenal medullary tumours Pheochromocytoma Rare tumours Lipoma, myelolipoma Metastatic lesion Others- cyst, abscess, haematoma

Adrenal Incidentaloma- Aetiology Risk of malignancy & functional tumours overestimated Condition Prevalence Adrenal cancer 1.9% Metastasis 0.7% Phaeochromocytoma 3.1% Conn’s syndrome 0.6% Subclinical Cushing’s Syndrome 6.4% Ca half of quoted, phaeo 2/3, conn’s half by excluding surgical series Cawood et al Eur J Endocrinol 2009

Adrenal Incidentaloma- Natural History Most are non functional adenoma Size of lesion crucial >25% malignant if >6cm 2% malignant if <4cm 20% develop subsequent hormone production 25% may increase in size NIH State of the Science guidelines 2002

Management Guidelines National Institute of Health State of the Science guidelines 2002 Young NEJM 2007 guidelines Singh et al ACP best practice guidelines J Clin Pathol 2008

Adrenal Incidentaloma Workup Whether it is functional Blood pressure, potassium (not reliable) Aldosterone/renin ratio 1mg overnight dexamethasone suppression test 24 hour urine metanephrine, catecholamines Plasma DHEAS level (optional) NIH State of the Science Guidelines 2002

Adrenal Incidentaloma Workup Whether it is malignant: CT scan findings >6cm high chance of malignancy Ideal lower cut off controversial 4cm cutoff- 90% sensitivity for cancer 76% of lesion excised were benign Smooth, sharp border, calcifications Angeli Hormone Res 1998 NIH State of the Science Guidelines 2002 Yong NEJM 2007

Adrenal Incidentaloma Workup Whether it is malignant: CT scan findings Adenoma has higher fat content Density (Hounsfield Unit): <10 likely adenoma Enhancement washout >50% at 15 minutes likely adenoma NIH State of the Science Guidelines 2002

Adapted from Dunnick AJR 2002 Adrenal Metastasis Adrenal Carcinoma Adapted from Dunnick AJR 2002

2.8x2.8x2.3cm pheochromocytoma 9x8x8cm benign adenoma Linos Hormone 2003

Adrenal Incidentaloma Workup CT guided biopsy Only recommended if known primary cancer i.e. not true incidentaloma Need to exclude phaeochromocytoma first! Random use give low diagnostic yield

Yield of CT Guided Biopsy Mazzaglia Arch Surg 2009

Adrenal Incidentaloma Workup MRI No proven benefit over CT scan Role of PET scan Only if known history of carcinoma 100% sensitivity in detecting metastasis 81% if CT only Frilling et al Surgery 2004

Nonfunctioning adenomas Management- Surgery If hormonal active or suspicious CT scan Laparoscopic approach recommended Crucial to consider the indication of surgery Surgical Unit Nonfunctioning adenomas Secreting adenomas Others Total Endocrine 18 (29.0) 41 (66.1) 3 (4.8) 62 General 95 (50.5) 54 (28.7) 39 (20.7) 188 Conzo Can J Surg 2009

NIH State of the Science Guidelines 2002 Management- Follow up CT scan at regular intervals 6/12/24 months Annual hormonal workup Discharge if static for 4 years NIH State of the Science Guidelines 2002

Subclinical Cushing’s Syndrome Subclinical Cushing’s Syndrome (SCS) Mild secretion of cortisol without clinically evident signs of hormone excess No universally accepted definition At least 2 HPA axis functional parameters Rossi J Clin Endocrinol Metab 2000

Subclinical Cushing’s Syndrome 5-20 % AI patients Large percentage with hyperlipidaemia, hypertension, diabetes Risk of cardiovascular diseases Lower bone density, increased fracture risk Surgery improves diabetic, BP control, lipid profile and obesity 376 AI patients The overall prevalence of Type 2 diabetes mellitus, hypertension, hyperlipidemia, and metabolic syndrome was 18.4, 54.9, 59.6, and 48.1%, respectively. Comlekci et al Endocrine 2009 Chiodini J Clin Endocrinol Metab 2009 Toniato Ann Surg 2009

Conclusions AI - common radiological finding Most are benign and indolent Size good predictor of malignant risk Regular follow up needed Expanding indications for surgery in laparoscopic era