Table 1: Endocrine investigations demonstrated marked ACTH-dependent hypercortisolism.

Test

Result

Reference range

ACTH

256.2 ng/L

7.2-63.3

Serum cortisol

>1650 nmol/L

170-492

24-hour urinary free cortisol

>31,389 nmol/24 h

0-200

24-hour urinary potassium

120 mmol/24 h

40-100

Chromogranin A

280 pmol/L

0-60

Urinary 5-HIAA

310 μmol/24 h

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