Lalloo, 50-years-old, a chronic smoker, presents with the history of hemoptysis. He was having truncal obesity and hypertension. He had an elevated ACTH level which was not suppressible with high dose dexamethasone. What would be the most probable diagnosis -
Bilateral adrenal hyperplasia
Adrenal adenoma
Pituitary tumour
Ectopic ACTH producing lung cancer