Adrenal Incidentaloma: An Update of its Management

1. Adrenal Incidentaloma:An Update of its Management 18th September 2004 Dominic Tai Division of Urology Department of Surgery Pamela Youde Nethersole Eastern Hospital

2. Agenda • Prevalence and pathologies • Diagnostic Evaluation • Risk of malignancy • Hormonal evaluation • Imaging • Surgical options • Take home messages

3. Definition • Clinically silent adrenal mass • Incidentally discovered by imaging performed for unrelated problems

4. Prevalence • Autopsy series of more than 8500 patients from 25 series: • 5.9% (1-32%) • CT: • 0.6-1.9% • Data obtained >10 yrs ago (thick cut CT 5mm-1cm) • Prevalence increases with age • <30 less than 1% • Middle age 3% • Elderly>70 10% • Kloos RT et al: Incidental discovered adrenal masses. Endocrine Rev 1995, 16:460-484

5. Pathology F. Mantero et al J. Clinical Endocrinol Metab 85:637-644, 2000 -

6. Diagnostic Evaluation • Assessment of risk of malignancy • Primary • Secondary • Hormonal evaluation • Subclinical endocrine activity is not uncommon in asymptomatic patients

7. Adrenocortical Carcinoma • Rare but lethal tumor • Overall 5 yr survival ~ 16% • For small tumor confined to adrenal gland ~42% • Major indicator of malignancy • Size • Other features for adrenal malignancy in CT: • Density >18 HU • Irregular tumor margin • Heterogeneity/hemorrhage/necrosis • Lymphadenopathy/invasion to adjacent organs

8. Distribution of diagnosis by tumor size(8 studies with 103 diagnoses determined by histology)

9. Recommendation for Non-functioning Adrenal Incidentaloma • High risk patients  surgical removal • Tumor size >6cm • Features of malignancy in imaging studies • Low risk patients  Follow-up • Tumor size <4 cm • Medium risk patients  both approach reasonable • Tumor size between 4-6 cm

10. Adrenal Metastasis • Frequent site for metastasis • 27% in 1000 consecutive autopsies of cancer patients • Incidence approaching 40% in patients with CA lung • Abrams HL et al. Cancer 3:74-85. 1950 • Metachronous isolated metastasis • Adrenalectomy may prolong median survival • Cord Sturgeon et al. Surgical clinics of North America. 84:2004

11. Fine needle Aspiration • Little role in differentiating different pathologies • Potentially serious complications • Concerns of track seeding • Sampling error • Negative biopsy unable to rule out malignancy • Inconclusive biopsy results may happen • Useful in evaluation of suspicious adrenal secondary • Important to rule out phaeochromocytoma first before attempting biopsy • Potentially life threatening hypertensive crisis

12. Incidence of SubclinicalEndocrine Activities • Hypercortisolism: 5-47% • Hyperaldosteronism: 1.6-3.8% • Phaeochromocytoma: 7-10% • Sex hormone secreting tumor: rare • George Mansmann et al. Endocrine Review25(2): 309-340

13. Hormonal EvaluationSubclinical Cushing Syn(Subclinical Autonomous Glucocorticoid Hypersecretion) • Symptoms and signs not apparent and specific • Screening • Low dose dexamethasone (1mg) suppression test • NIH State of Science Recommendation • Confirmation • High dose dexamethasone suppression • ACTH • 24 hr urine free cortisol

14. Hormonal EvaluationPhaeochromocytoma • Endocrine test advised in all incidentalomas • (including normotensive ones) • 24 hr urinary free catecholamines • its metabolites • VMA and metanephrines • Plasma free catecholamine metabolites (?more sensitive) • NIH State of Science Recommendation

15. Hormonal EvaluationPrimary Aldosteronism • Screening advised • Even patient normokalaemic • Screening test • Aldosterone/plasma renin activity • NIH State of Science Recommendation • Lateralization • CT/MRI • Scintigraphy • Adrenal vein sampling

16. Imaging studies • CT • Still remain an accurate tool • 97-99% sensitivity (spiral thin cut) • Solitary lesion >1cm with normal contralateral gland • Adrenal limb thickness • Lingam et al AJR 2003;181(3): 843-9 • MRI • Inconclusive results when compared with CT • May be slightly more sensitive to differentiate the pathology • Very sensitive in detecting phaeochromocytoma • (light bulb appearance on T2 images) • Useful for staging for advanced carcinoma • Georg et al Endocrin Review 2004;25(2) 309-340

17. Imaging StudiesUSG • Less sensitive than CT and MRI • For adrenal tumor < 3cm • Missed 35% of lesion • Almost 100% were detected by CT • Suzuki K et al. J. Urol 154: 484-486 1995 • Operator dependent • Limited role for diagnosis and Follow-up

18. Imaging StudiesScintigraphy • NP-59 • Role in differentiation • Hyperplasia/adenoma • Use in incidentaloma controversial • MIBG • Only indicated for suspected malignant/ familial case

19. Indication for adrenalectomy • Suspicion for malignancy • Mass with hormonal hypersecretion

20. Adrenalectomy European Association of Urology Guideline 2002 Laparoscopic Superior to Open • Expert opinion : Superior • Level of evidence : 1b • Recommendation : Grade A

21. Contraindications • Invasive cortical carcinoma • Adjacent organ/major vessel invasion • Regional lymphadenopathy • Solitary adrenal metastasis • Can be safely managed by Lap adrenalectomy • Obesity and history of abdominal operation • No more contraindicated

22. Role of Open Surgery

24. Take Home Messages • Adrenal incidentaloma requires • Hormonal evaluation • Assessment for risk of malignancy • Risk of malignancy is mainly determined by its size • Laparoscopic adrenalectomy is the gold standard for adrenal gland removal • Except in invasive malignancy

25. Thank You!