Adrenal incidentaloma: subclinical Cushing's syndrome

Adrenal incidentalomas and subclinical Cushing's syndrome

The issue of cortisol secretion by adrenal masses discovered incidentally in the course of evaluation for an unrelated reason (Subclinical Cushing's Syndrome) is among the most controversial and contentious issues in clinical endocrine practice. This derives from our relatively poor ability to accurately determine clinically those at increased risk among the majority who are not, the significant limitations of available diagnostic tests, the lack of a gold standard for diagnosis or even universally agreed criteria for diagnosis. A consensus for diagnostic criteria would be a good first step on which to base the kinds of studies needed to address our uncertainties. In the meantime, we must be careful to recognize the limitations of the current evidence avoid the pitfalls of overestimation of disease prevalence and of the benefits of therapy resulting from advances in diagnostic imaging and sophisticated laboratory testing. There remains an essential role for clinical judgment.

Leiomyoma of the adrenal gland presenting as a non-functioning adrenal incidentaloma: case report and review of the literature

A 31-year-old woman was incidentally found to have a large right adrenal mass by computed tomography imaging and underwent a workup that included endocrinological evaluation and positron emission tomography imaging. Laboratory results revealed the mass to be non-functioning. Imaging studies revealed a 9-cm heterogeneous mass that was not FDG avid. Because of concern for adrenal cortical carcinoma, the patient underwent a successful right adrenalectomy. Pathology examination demonstrated an 11-cm circumscribed mass consisting of uniform spindle cells without nuclear pleomorphism, necrosis, or mitotic activity. The diagnosis of leiomyoma was supported by a panel of immunohistochemical stains. Adrenal leiomyomas have been reported in the literature, although most are small and not preoperatively suspicious for malignancy. This case illustrates that benign tumors such as leiomyomas, when large and heterogeneous on imaging, can clinically mimic adrenal cortical carcinomas and should be included in the differential diagnosis of adrenal incidentalomas.

CT of primary cystic pancreatic neoplasms: can CT be used for patient triage and treatment?

OBJECTIVE

The purpose of this study was to determine whether CT can be used to distinguish serous cystadenomas from mucinous cystadenomas or cystadenocarcinomas of the pancreas and play an enhanced role in patient triage and treatment.

MATERIALS AND METHODS

A blinded retrospective analysis of CT scans from 50 patients with pathologically proven primary cystic pancreatic neoplasms was performed independently by three radiologists. Using classic CT criteria as reported in the literature, each tumor was categorized as definitely serous, mucinous, or indeterminate. Tumor location, size, presence of calcification, and size of largest cyst were recorded. Data for each reviewer were analyzed independently. Consensus data were then subjected to multivariate logistic regression analysis.

RESULTS

The ability of our reviewers to diagnose serous neoplasms ranged from 23% to 41%. Eight mucinous neoplasms were mistaken for serous tumors by two of the three reviewers. When consensus between at least two of the three reviewers was used for diagnosis, 27% of serous neoplasms were correctly diagnosed and all of the mucinous tumors were correctly identified as uncertain or mucinous, yielding the same clinical end point. For multivariate logistic regression analysis, a cyst smaller than 2 cm had a statistically significant association (p = 0.005) with serous tumors, and the presence of peripheral tumoral calcification had a statistically significant association (p = 0.01) with mucinous tumors.

CONCLUSION

There is significant variability in the CT appearance of serous and mucinous neoplasms of the pancreas, making CT an insensitive tool for differentiating these tumors. All tumors with peripheral calcifications were identified as mucinous neoplasms.

Management approaches to adrenal incidentalomas. A view from Rochester, Minnesota

Two biproducts of the revolution in diagnostic imaging techniques are unintended discoveries, and uncertainty for the patient and the clinician. To address the uncertainty associated with adrenal incidentalomas, clinicians need to understand the definition, differential diagnosis, and options for assessment with respect to functional status and malignancy potential. This article presents an algorithmic approach that addresses these issues.

Incidentalomas. A disease of modern technology

The optimal strategy for hormonal screening of a patient with any incidentally discovered adrenal or pituitary mass is unknown. Our review of the endocrinologic literature supports the view that such patients are at slightly increased risk for morbidity and mortality. There is a benefit of early diagnosis for at least for some of the disorders, suggesting the importance of case finding. The data in Tables 1 and 4 illustrate that clinically diagnosed hormone-secreting adrenal and pituitary tumors are far less common than incidentalomas. From a clinical perspective, our ability to determine accurately those at increased risk among the vast majority who are not at increased risk is poor. Given the limitations of diagnostic tests, effective hormonal screening requires a sufficiently high pretest probability to limit the number of false-positive results. This condition is met to varying degrees in the patient with an adrenal mass or small incidentally discovered pituitary mass but no signs or symptoms of hormone excess. Even the more common lesions such as pheochromocytoma and prolactinoma are relatively rare. Subjecting patients to unnecessary testing and treatment carries its own set of risks. Initial costs aside, testing may result in further expense and harm as false-positive results are pursued, producing the cascade effect described by Mold and Stein as a "chain of events (which) tends to proceed with increasing momentum, so that the further it progresses the more difficult it is to stop." The extensive evaluations performed in some patients with incidentally discovered masses may reflect the unwillingness of many physicians to accept uncertainty, even in the case of extremely unlikely diagnoses. This unwillingness may be driven, in part, by fear of potential malpractice liability, the failure to appreciate the influence of prevalence data on the interpretation of diagnostic testing, or other factors. Indeed, the major justification for further evaluation of these patients is not so much to avoid morbidity and mortality for rate patients who truly are at increased risk but rather to reassure those in whom further testing is negative (and to reassure ourselves). Physicians must take care not to create inappropriate anxiety in patients by overemphasizing the importance of an incidental finding unless it is associated with a realistic clinical risk. Our recommendations utilize currently available information to minimize the untoward effects of the cascade. As evidence accumulates, recommendations may need to be revised. The benefit of diagnosis of one of these adrenal or pituitary disorders must be considered in the context of the patient's overall condition. Studies are needed to analyze the utility in clinical practice of hormonal screening for these common radiologic findings. We need to use these studies to identify the critical gaps in our knowledge and to adopt the epidemiologic methods of evaluation of evidence that have been applied to preventive measures. We must be careful to recognize lead-time bias in which survival can seem to be lengthened when screening simply advances the time of diagnosis, lengthening the period of time between diagnosis and death without any true prolongation of life. Length bias refers to the tendency of screening to detect a disproportionate number of cases of slowly progressive disease and to miss aggressive cases that, by virtue of rapid progression, are present in the population only briefly. Endocrinologists must avoid the pitfalls of overestimation of disease prevalence and of the benefits of therapy resulting from advances in diagnostic imaging. Clinical judgment based on the best available evidence should be complemented and not replaced by laboratory data.