Best Practice & Research Clinical Endocrinology & Metabolism

Preface

David C. Aron — 2012-02-01

Why an entire issue devoted to incidentalomas? Incidentalomas of endocrine glands continue to be a fairly hot issue as reflected by increased citations in the literature. From 1970–79 there were 4 papers with the words “incidental,” “incidentally,” or “incidentaloma” in the title – <1 per year. From 1980–89 there was an average of 2.7/year, while from 1990 the average has been >10 per year. These numbers do not include papers in journals that are not indexed in Medline. A Google search for “incidentaloma” identified 148,000 hits. The adrenal incidentaloma which was the focus of much of the literature for many years has been joined by incidentalomas of virtually every endocrine organ. Controversy reigns as expert individual opinion is being superceded (rightly or wrongly) by systematic reviews, position statements, and practice guidelines issued sponsored by expert organizations, e.g. the Italian Association of Clinical Endocrinologists (AME) and the Endocrine Society to name just two. Remarkable technological advancements in the practice of endocrinology have often been, like in technological advancements in general, associated with unintended consequences. Among the unintended consequences is the identification of preclinical or subclinical ‘disease’ related to the extensive use of sophisticated diagnostic tools. Technology continues to advance providing clearer images of findings of unknown clinical significance: an incidentaloma may represent a finding of no significance at all or a ticking time bomb such as an adrenal cancer that may result in the patient’s death.

Incidentalomas – A “disease” of modern imaging technology

Jennifer Wagner, David C. Aron — 2012-02-01

The evolution of new diagnostic techniques has revolutionized the practice of medicine and in fact, the nature of medicine itself. Technology has also expanded the “visual” field of medicine: the naked eye was assisted by the light microscope and then electron microscope to see smaller and smaller features while radiology has permitted “non-invasive” identification of internal structures. However, there are unintended consequences one of which is the discovery of an anomaly during the course of looking for something else – incidental findings and incidentalomas. Technology in general and imaging specifically offer much in service to physicians and their patients. However, it behoves physicians to ensure that technology supplements but does not replace good clinical judgment. This essay aims to put the issue of incidental findings related to advancing technology (especially imaging technology) into a broader context.

Evidence-based endocrinology – Illustrating its principles in the management of patients with pituitary incidentalomas

I. Bancos, N. Natt, M.H. Murad, V.M. Montori — 2012-02-01

Incidentally discovered pituitary lesions are commonly encountered in the current era of ever-increasing imaging. Individualizing a particular approach implies a thorough analysis of existing evidence and balancing it against different patient expectations.We will illustrate the application of principles of Evidence-Based Medicine to a case of a pituitary incidentaloma by formulating questions that are important to patient care and finding related evidence. Our objective is to reflect the opportunities and the challenges that an evidence-based clinical approach offers to clinicians and patients.

Radiological evaluation of adrenal incidentalomas – Current methods and future prospects

S. McDermott, O.J. O’Connor, C.G. Cronin, M.A. Blake — 2012-02-01

Incidental adrenal lesions are very common. Computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) all have a role to play in characterizing adrenal lesions. The purpose of this review is to discuss the rationale behind both established and emerging imaging techniques. We also discuss how to follow up incidentally found lesions.

Advances in pituitary imaging technology and future prospects

Sachit Shah, Adam D. Waldman, Amrish Mehta — 2012-02-01

There have been substantial advances in pituitary imaging in the last half-century. In particular, magnetic resonance imaging is now established as the imaging modality of choice, providing high quality images of the hypothalamic–pituitary axis and adjacent structures. More recent technological advances, such as the emergence of 3 Tesla MRI, are already being widely incorporated into imaging practice. However, other advanced techniques, including a variety of potential imaging biomarkers, still require further research to evaluate their potential and define their precise role. The recent development of intraoperative MRI appears promising and may have the potential to improve the outcome of pituitary surgery. Modern high quality imaging inevitably leads to the discovery of incidental lesions, including those within the pituitary gland, although it also plays a central role in their subsequent evaluation and management.

Pituitary incidentaloma

Israel B. Orija, Robert J. Weil, Amir H. Hamrahian — 2012-02-01

Pituitary incidentalomas (PIs) are commonly encountered in clinical practice. While most are microincidentalomas (<1 cm) and not functional, in some cases their identification may lead to discovery of unrecognized abnormalities such as pituitary hormonal deficiencies, excess hormone secretion or visual field defects. Although the majority are pituitary adenomas, the potential list of differential diagnosis is extensive. A limited biochemical work up for asymptomatic patients with microincidentalomas, to include measurement of prolactin and IGF-1, is reasonable, with further studies to be tailored based on the clinical picture. All patients with macroincidentalomas (≥1 cm) should be evaluated for hypopituitarism and undergo visual field testing if the sellar mass abuts or compresses the optic chiasm. Most PIs can be followed, closely without surgery over time, but some may require surgical removal, especially if they are found to be macroincidentalomas at presentation, encroaching on or abutting the optic chiasm, or are found to be functional, excluding prolactinomas. Recovery of pituitary function may be seen in some patients with mass effect following resection of a sellar mass. The association of headache and pituitary incidentalomas remains a diagnostic challenge. There are no randomized controlled studies to guide the follow up approach when surgery is not indicated; most of the follow up algorithms in the literature are based on personal experience. Most retrospective series on natural history indicate that microincidentalomas tend not to grow; without a need for long-term follow up unless the patient becomes symptomatic. Macroincidentalomas, on the other hand, have a propensity to grow and need a more aggressive follow up approach to minimize morbidity.

Adrenal incidentalomas

David Aron, Massimo Terzolo, T.J. Cawood — 2012-02-01

The term adrenal incidentaloma (AI) is usually defined as an adrenal mass unexpectedly detected through an imaging procedure performed for reasons a priori unrelated to adrenal dysfunction or suspected dysfunction. The preferred approach to their management in terms of diagnosis, follow-up, and treatment remain controversial despite a state-of-the-science conference sponsored by the U.S. National Institutes of Health. Although most experts’ recommendations tend to be relatively minor variations of the conference’s approach, dissenting voices have been heard. Despite their frequent appearance, the challenge remains to recognize and treat the small percentage of AI that do pose a significant risk, either because of their hormonal activity or because of their malignant histology, while leaving the rest alone. Although the differential diagnosis of an incidentally discovered mass is quite extensive, most AIs are non-secreting cortical adenomas. The noninvasive differentiation of benign and malignant lesions depends upon imaging characteristics, and sometimes radiologic diagnosis can be definitive, but often it is not, Among function lesions, autonomous cortisol production seems to be the most common and may be associated with increased cardiovascular risk and clinical features of the “metabolic syndrome.” Follow-up of cases in which a specific diagnosis is not made initially involves assessment for growth and development of hormonal function, but even here, controversy about the extent of evaluation persists.

Thyroid incidentaloma

Judy Jin, Christopher R. McHenry — 2012-02-01

Thyroid incidentaloma is defined as an unsuspected, asymptomatic thyroid lesion that is discovered on an imaging study or during an operation unrelated to the thyroid gland. Thyroid incidentalomas are most commonly detected on ultrasound, followed in frequency by computed tomography (CT) and magnetic resonance imaging (MRI), carotid duplex scanning and 2-18[F] fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET). The incidence of carcinoma in incidentally discovered thyroid disease is not insignificant. There are significant shortcomings of CT, MRI and PET imaging of the thyroid gland. As result, a thorough sonographic evaluation of the thyroid gland should be performed in all patients with a thyroid incidentaloma, regardless of the radiographic features identified on the “non thyroid “imaging modality. A sonographically confirmed thyroid nodule should be managed in an identical fashion to a clinically apparent thyroid nodule.

Pancreatic incidentalomas

Xeily Zárate, Nicholas Williams, Miguel F. Herrera — 2012-02-01

Pancreatic incidentalomas are defined as asymptomatic pancreatic lesions, discovered incidentally by imaging for an unrelated indication. They are being discovered with increasing frequency as the use of high quality cross sectional imaging is becoming more widespread. These lesions cover a wide spectrum of pathology from benign simple cysts through potentially malignant lesions such as intraductal papillary mucinous neoplasia, to frankly malignant adenocarcinoma. In this article we outline the incidence, imaging characteristics and natural history of the various incidental lesions with emphasis to neuroendocrine tumors. A diagnostic approach is also suggested, including the rational use of further imaging, serum biochemistry and the utility of ultrasound guided aspiration of cyst fluid if present. We examine several proposed classification systems and discuss the role of surgery, surveillance and prognosis.

Ovarian incidentaloma

Meir Jonathon Solnik, Carolyn Alexander — 2012-02-01

Incidental adnexal masses occur with relatively high frequency in post-menopausal women, with a prevalence rate of 3.3–18% in asymptomatic patients. Unilocular, benign-appearing ovarian cysts represent the vast majority of abnormal findings at transvaginal ultrasonography. As many as 80% will resolve over a period of several months; if persistent, unchanged, less than 10 cm, and with normal CA-125 values, the likelihood of an invasive cancer is sufficiently low that observation should be offered. More recent investigations support the use of secondary imaging modalities such as MRI, which may help differentiate benign from malignant masses. Surgical management plays a key role when patients are symptomatic regardless of age, menopausal and have documented changes in cyst characteristics, experience elevations in tumor markers or have symptoms suggestive of a hormone-producing neoplasm. High level, evidence-based screening guidelines have yet to be developed.

Keyword index

2012-02-01