Minor morphologic abnormalities of adrenal glands at CT: Prognostic importance in patients with lung cancer

PURPOSE: To determine the prognostic importance of minor morphologic abnormalities of the adrenal glands at computed tomography (CT) in patients with lung cancer. MATERIALS AND METHODS: The study was approved by the committee on human research; written informed consent was not required. The authors retrospectively identified 197 patients with lung cancer who underwent serial chest or abdominal CT and did not have a focal adrenal mass at baseline CT. Two readers independently classified the morphologic features of each adrenal gland as normal, smoothly enlarged, or nodular at initial CT examination. They separately recorded the presence or absence of metastases to the adrenal glands (ie, any new focal adrenal mass) at final CT examination; a third independent reader arbitrated when interpretations were discordant (n = 11). Multivariate Cox proportional hazard models were used to assess for associations between baseline adrenal gland morphologic features and subsequent development of adrenal metastases. RESULTS: At initial CT, reader I classified 253 (64%), 70 (18%), and 71 (18%) of the 394 adrenal glands and reader 2 classified 258 (65%), 45 (11%), and 91 (23%) of these glands as normal, smoothly enlarged, or nodular, respectively. The readers had moderate interobserver agreement regarding the classification of adrenal gland morphologic features (kappa = 0.54). Metastases subsequently developed in 13 adrenal glands in 11 patients. Cox proportional hazard models revealed no significant association between baseline adrenal gland morphologic features and subsequent development of adrenal metastases (P = .50 and P = .20 for readers 1 and 2, respectively). CONCLUSION: In patients with lung cancer, smooth enlargement or nodularity of the adrenal glands at baseline CT is not associated with increased risk of subsequently developing adrenal metastases. (C) RSNA, 2005.