A patient with cushinoid features presents with hemoptysis; he shows no response to dexamethasone suppression test; most likely diagnosis here is:

Answer is C (Ca lung with ectopic ACTH production); Lack of suppression to dexamethasone challenge (ACTH producing tumor) and presence of hemoptysis (Carcinoma lung) in a patient with Cushinoid features suggests a diagnosis of Carcinoma lung with ectopic ACTH secretion. As a method of diagnostic workup of any patient with suspected Cushings we screen the patient with plasma coisol levels at 8:00 a.m. in the morning. Those with increased coisol levels are subjected to a dexamethasone supression test. In the given question there is lack of suppression to dexamethasone challenge so option (d) is out. Out of the choices remaining the presence of hemoptysis points towards the diagnosis of carcinoma lung with ectopic ACTH.