The Role of Nephrotomography in the Diagnosis of Adrenal Tumors

Accurate roentgenographic demonstration of adrenal tumor in clinically suspected cases is helpful both to the clinician in diagnosis and to the surgeon in planning treatment. Conventional plain films of the abdomen, excretory urography, and retroperitoneal pneumography have been the principal roentgen tools used for study of the adrenal region. None have been entirely satisfactory. Recent experience with nephrotomography indicates this is practical and reliable in the demonstration of adrenal tumors and may be a valuable adjunct to conventional methods of examination (1). Administration of large quantities of contrast material produced prolonged opacification of the kidneys, spleen, liver, and adrenal tumors without opacification of fat. It was believed that the large periadrenal fat deposits in patients with Cushing's syndrome would provide an excellent contrast to an opacified adrenal lesion and, when combined with body-section roentgenography, make it possible to separate overlying shadows and demonstrate the presence and anatomic features of an adrenal tumor. Because of the problems associated with retroperitoneal pneumography and the relative ease and potential advantages of nephrotomography, we have employed the latter in this series of patients in an effort to evaluate its diagnostic potential in suspected adrenal disease. Study Group The series consisted of 125 consecutive cases of suspected adrenal disease referred for nephrotomography since 1961. In none had tumors been previously identified with certainty on plain films or excretory urograms. The patients ranged in age from sixteen to sixty-seven years. Table I summarizes the referral diagnoses. In 46 patients with Cushing's syndrome studies of base-line plasma, 17- hydroxycorticosteroids, and urinary excretion of 17-ketosteroids and 17-ketogenic steroids and their response to dexamethasone suppression and metapyrone challenge indicated an underlying cause of adrenal cortical hyperplasia in 23 and of functioning adrenal tumor in 23. In 9 additional patients some clinical features were suggestive of Cushing's syndrome, but the results of steroid studies were incomplete. In addition, 25 examinations were undertaken in patients with a clinical course or study suggestive of pheochromocytoma. Prior roentgenographic examinations in 33 patients incidentally raised the question of an adrenal mass. Most of the 33 were undergoing study for hypertension of possible renal vascular origin and had no clinical or laboratory evidence of an adrenal tumor. Five patients with primary aldosteronism were examined. The remaining 7 patients were referred for various reasons, including possible metastatic or recurrent carcinoma, adrenal calcification, and hirsutism. One case is included in which nephrotomography for suspected renal disease incidentally revealed an adrenal adenoma.