🛰️Adrenal Incidentaloma Flashcards
(12 cards)
What is adrenal incidentaloma?
Lesion > 1 cm in diameter discovered “accidentally” during a radiographic examination performed for other reason.
Differential diagnosis of an incidentally discovered Adrenal mass
History taking for adrenal incidentaloma
Functional
- Assume all functional adrenal tumor are pheochromocytoma until proven otherwise
Hypercortisolism (Cushing’s Syndrome): sudden or unexplained weight gain, proximal muscle weakness, easy bruising, history of hard-to-control DM or HTN, early onset or severe osteoporosis or a history of easy fractures, menstrual irregularities, fatigue, depression.
Hyperaldosteronism (Conn’s Syndrome): history of hypertension and/or hypokalemia, muscle cramping, weakness, intermittent periodic paralysis, fluid retention, polyuria, polydipsia
Pheochromocytoma: episodes or “spells” of unexplained anxiety, palpitations, tremors, headache, sweating or feeling hot, episodic or severe high blood pressure.
Hyperandrogenism: new onset hirsutism, acne, deepening voice, increased muscle bulk.
Carcinoma or metastatic disease: weight loss, abdominal pain, fever, paraneoplastic syndrome.
Nonfunctional
Present on imaging or with symptoms like pain or palpable mass
Physical Examination for Adrenal incidentaloma
Vital signs and
Hypercortisolism (Cushing’s Syndrome): central obesity with thin extremities, prominent supraclavicular or dorso cervical fat pads (i.e. “buffalo hump”), thick purple striae on abdomen, easy bruising, weight gain, proximal muscle weakness, HTN
Hyperaldosteronism (Conn’s Syndrome): difficult to control HTN or low K+
Pheochromocytoma: anxiety, heart palpitations, tremors, severe HTN
Hyperandrogenism: Hirsutism, acne, deep voice
Overview of investigation for Adrenal Incidentaloma
Radiographic characteristic ( Benign vs Malignant) adrenal masses
CT - Sensitivity 90%, Specificity 95-99%. Preferred than MRI.
MRI - T1 and T2 weighed images may be able to differentiate between adenoma, malignancy and pheochromocytoma.
NP59 or Seleno cholesterol scintigraphy - for functional tumors.
FDG-PET CT - if CT/MRI inconclusive & suspicious of malignancy.
Characteristics of Adrenal Incidentalomas on Imaging
Screening for Functional Adrenal incidentaloma
Screen for pheochromocytoma
Plasma free metanephrines
- Positive if elevated > 2 x the upper limit of normal [ULN].
- < 2x may be false positives, considered equivocal and no classic signs → confirm with 24-hour urine metanephrines (less likely to be falsely positive).
Screen for Hyperaldosteronism (Conn’s Syndrome)
Aldosterone level, Plasma Renin Activity (PRA), Aldo : Renin Ratio (ARR)
- Positive if ARR is > 20 AND the Aldo is > 8
- Considered if patient has HTN or a history of hypokalemia.
Screen for Hypercortisolism (Cushing’s Syndrome)
Dexamethasone suppression test (DST)
- Prescribe 1 mg of oral dexamethasone at 11 PM → next morning at 8 AM, cortisol and dexamethasone level are drawn.
- If 8 AM cortisol < 1.8 mcg/dL, cortisol excess is ruled out.
- Cortisol between 1.8 and 5.0 mcg/dL may represent mild cortisol excess:
- Repeat DST annually for 5 years.
- Failure to suppress below 5.0 mcg/dL raises concern for cortisol excess → 24-hour urinary cortisol and refer to Endocrinology or Endocrine Surgery.
Any role of FNAC in adrenal incidentaloma?
- Cannot differentiate between benign and malignant. No biopsy unless suspected metastasis.
- Exclude pheochromocytoma before FNAC.
- Complications - adrenal hematoma, abdominal pain, hematuria, pancreatitis, pneumothorax.
Surgery in Unilateral adrenal mass
Follow up for Benign Incidentaloma
- Repeat imaging 6, 12 & 24 months for benign looking tumors. If ↑ > 1cm over 6 to 12 months for resection.
- Functional testing at annually for 4 years
Overview of Adrenal tumour
