Application of different localization methods in diagnosis of ectopic ACTH syndrome

Objective To study the application of different localization methods in diagnosis of ectopic ACTH syndrome.Methods Clinical data about 20 patients with ectopic ACTH syndrome admitted to our hospital from 2000 to 2010 were retrospectively analyzed.Results The IPS/P＞2 in bilateral petrosal sinus sample（BIPSS） could not absolutely rule out the diagnosis of ectopic ACTH syndrome.Most primary lesions could be detected by chest film and CT scan.The ACTH level measured in peripheral vein sample was not of great help for the diagnosis of ectopic ACTH syndrome.Conclusion Diagnosis of primary ectopic ACTH syndrome is quite difficult,which requires the combination of multiple imaging methods.