The natural history of incidentally discovered adrenocortical adenomas: a retrospective evaluation

Natural History of Adrenal Incidentalomas With and Without Mild Autonomous Cortisol Excess: A Systematic Review and Meta-analysis

BACKGROUND

Adrenal incidentalomas are mostly benign nonfunctioning adrenal tumors (NFATs) or adenomas causing mild autonomous cortisol excess (MACE), but their natural history is unclear.

PURPOSE

To summarize the follow-up data of adults with NFAT or MACE to determine the proportions of tumor growth, malignant transformation, and incident changes in hormone function; the prevalence of incident cardiometabolic comorbid conditions; and mortality.

DATA SOURCES

MEDLINE, Embase, Cochrane, and Scopus (January 1990 to February 2019) and bibliographies of identified articles, without language restriction.

STUDY SELECTION

Studies that included 20 or more conservatively managed patients with NFAT or MACE and reported outcomes at baseline and after at least 12 months of follow-up.

DATA EXTRACTION

Pairs of reviewers extracted outcomes and assessed methodological quality.

DATA SYNTHESIS

Thirty-two studies reported outcomes of 4121 patients with NFAT or MACE, 61.5% of whom were women; the mean age was 60.2 years, and mean follow-up was 50.2 months. Mean tumor growth was 2 mm over 52.8 months. Clinically significant tumor enlargement (≥10 mm) occurred in 2.5% of patients, and none developed adrenal cancer. Clinically overt hormone excess was unlikely to develop (<0.1%) in patients with NFAT or MACE. Only 4.3% of patients with NFAT developed MACE, and preexisting MACE was unlikely to resolve (<0.1%). Hypertension, obesity, dyslipidemia, and type 2 diabetes were highly prevalent (60.0%, 42.0%, 33.7%, and 18.1% of patients, respectively) and were more likely to develop and worsen in MACE than NFAT. New cardiovascular events were more prevalent in MACE (15.5%) than NFAT (6.4%). Mortality was 11.2% and was similar between NFAT and MACE.

LIMITATION

Evidence was scarce, and definitions of MACE and comorbid conditions were heterogeneous.

CONCLUSION

During follow-up, NFAT and MACE do not show clinically relevant changes in size or hormonal function, but they may carry an increased risk for cardiometabolic comorbid conditions.

PRIMARY FUNDING SOURCE

None.

PRKACA Mutations in Adrenal Adenomas: Genotype/Phenotype Correlations

Untargeted, next generation sequencing approaches have provided deep insights into genetic events that result in unopposed steroidogenesis from the adrenal cortex. In particular, somatic mutations in the gene encoding the catalytic subunit α of protein kinase A (PKA) (PRKACA) were identified independently by several groups as the most frequently altered gene in cortisol-producing adenomas. Detailed functional studies could explore the molecular consequences of these hot-spot mutations and large international cohorts have provided the basis to explore the clinical characteristics associated with this mutation. Thereby, PRKACA mutations are highly specific for cortisol over-secretion, while they are absent or very rare in the context of other adrenal diseases. Patients carrying these somatic mutations are affected by a more severe phenotype and are identified at a younger age. Thus, these genotype/phenotype correlations provide further evidence for the importance of PKA-dependent pathways for adrenal physiology and disease.

Work-up of the Incidental Adrenal Mass

CONTEXT

Incidental adrenal masses (or adrenal incidentalomas [AI]) are a common finding during imaging and are present in up to 5% of the computed tomography (CT) scans performed on the general population. The best way to manage these lesions is still under discussion.

OBJECTIVE

To evaluate recent literature and available guidelines regarding the work-up of AIs.

EVIDENCE ACQUISITION

We used a medical search engine to identify studies published in the past 5 yr regarding AIs. We also evaluated current guidelines and the most relevant papers published before 2010.

EVIDENCE SYNTHESIS

Unenhanced and contrast-enhanced CT, with laboratory tests to exclude functional lesions, are the most sensitive and specific methods currently available for the characterisation of adrenal masses. Magnetic resonance imaging, positron emission tomography-CT and fine-needle aspiration biopsy can be used as adjunct diagnostic tools in indeterminate lesions but are rarely indicated. In a relatively high number of indeterminate nodules, follow-up or surgery is suggested, although most of these lesions turn out to be benign.

CONCLUSIONS

Various imaging modalities, with CT being most important, are available to diagnose malignant and functional lesions in AIs. An improved identification of benign lesions is warranted to reduce the number of unnecessary surgeries and follow-up examinations in patients with benign lesions.

PATIENT SUMMARY

We performed a review of the literature on and guidelines for the management of incidental adrenal masses. It is possible to detect the presence of lesions that require surgery in the majority of cases. Follow-up is required for lesions that are not treated surgically.

cAMP signaling in cortisol-producing adrenal adenoma

The cAMP signaling pathway is one of the major players in the regulation of growth and hormonal secretion in adrenocortical cells. Although its role in the pathogenesis of adrenocortical hyperplasia associated with Cushing's syndrome has been clarified, a clear involvement of the cAMP signaling pathway and of one of its major downstream effectors, the protein kinase A (PKA), in sporadic adrenocortical adenomas remained elusive until recently. During the last year, a report by our group and three additional independent groups showed that somatic mutations of PRKACA, the gene coding for the catalytic subunit α of PKA, are a common genetic alteration in patients with Cushing's syndrome due to adrenal adenomas, occurring in 35-65% of the patients. In vitro studies revealed that those mutations are able to disrupt the association between catalytic and regulatory subunits of PKA, leading to a cAMP-independent activity of the enzyme. Despite somatic PRKACA mutations being a common finding in patients with clinically manifest Cushing's syndrome, the pathogenesis of adrenocortical adenomas associated with subclinical hypercortisolism seems to rely on a different molecular background. In this review, the role of cAMP/PKA signaling in the regulation of adrenocortical cell function and its alterations in cortisol-producing adrenocortical adenomas will be summarized, with particular focus on recent developments.

Long-term follow-up in adrenal incidentalomas: an Italian multicenter study

CONTEXT

The long-term consequences of subclinical hypercortisolism (SH) in patients with adrenal incidentalomas (AIs) are unknown.

SETTING AND PATIENTS

In this retrospective multicentric study, 206 AI patients with a ≥5-year follow-up (median, 72.3 mo; range, 60-186 mo) were enrolled.

INTERVENTION AND MAIN OUTCOME MEASURES

Adrenocortical function, adenoma size, metabolic changes, and incident cardiovascular events (CVEs) were assessed. We diagnosed SH in 11.6% of patients in the presence of cortisol after a 1 mg-dexamethasone suppression test >5 μg/dL (138 nmol/L) or at least two of the following: low ACTH, increased urinary free cortisol, and 1 mg-dexamethasone suppression test >3 μg/dL (83 nmol/L).

RESULTS

At baseline, age and the prevalence of CVEs and type 2 diabetes mellitus were higher in patients with SH than in patients without SH (62.2 ± 11 y vs 58.5 ± 10 y; 20.5 vs 6%; and 33.3 vs 16.8%, respectively; P < .05). SH and type 2 diabetes mellitus were associated with prevalent CVEs (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.1-9.0; and OR, 2.0; 95% CI, 1.2-3.3, respectively), regardless of age. At the end of the follow-up, SH was diagnosed in 15 patients who were without SH at baseline. An adenoma size >2.4 cm was associated with the risk of developing SH (sensitivity, 73.3%; specificity, 60.5%; P = .014). Weight, glycemic, lipidic, and blood pressure control worsened in 26, 25, 13, and 34% of patients, respectively. A new CVE occurred in 22 patients. SH was associated with the worsening of at least two metabolic parameters (OR, 3.32; 95% CI, 1.6-6.9) and with incident CVEs (OR, 2.7; 95% CI, 1.0-7.1), regardless of age and follow-up.

CONCLUSION

SH is associated with the risk of incident CVEs. Besides the clinical follow-up, in patients with an AI >2.4 cm, a long-term biochemical follow-up is also required because of the risk of SH development.

Clinical outcomes of surgical treatment and longitudinal non-surgical observation of patients with subclinical Cushing's syndrome and nonfunctioning adrenocortical adenoma

Aims:

To investigate the outcomes of the surgical management and longitudinal assessment of patients with subclinical Cushing's syndrome (SCS) and nonfunctioning adrenocortical adenoma (NFA).

Materials and Methods:

Between the years 1995 and 2008, 73 patients with asymptomatic adrenocortical adenoma were enrolled. They were informed of the risks and benefits of adrenalectomy and conservative management, and then chose the treatment.

Results:

SCS was observed in 13 patients (17.8%) and NFA in 60 patients (82.2%). Tumor size in SCS was significantly larger than that in NFA (34.6 ± 9.7 mm vs. 24.5 ± 8.0 mm in diameter, P=0.001). Of the SCS patients, 7 also suffered from hypertension (HT), 2 from diabetes mellitus (DM) and 3 from hyperlipidemia (HL). After adrenalectomy, the insulin dose could be reduced in 2 (100%) patients with DM, in 5 (71.4%) of those with HT and in 2 (66.7%) of those with HL. In the NFA surveillance group, 1 (2.6%) case developed into SCS 3 years after the initial presentation and an increase in size of the tumor was observed in 1 (2.6%), with a mean follow-up of 51.2 months.

Conclusions:

Surgical resection may be beneficial for the control of SCS and is likely to provide improvement of concomitant HT, DM and HL. Although NFA can be managed conservatively, its size and hormonal activities may change longitudinally. Thus, long-term follow-up is necessary for NFA.

Subclinical Cushing's syndrome

The routine use of abdominal procedure has significantly increased the incidental finding of adrenal masses. The prevalence of these tumors, commonly defined as adrenal incidentalomas, ranges between 2-3% in autopsy and 4% in radiological series, reaching 5-8% in oncological studies and increasing with patients age. Although clinically silent, in 5-20% of cases, adrenal incidentalomas are responsible for a subtle cortisol overproduction, commonly defined as "subclinical Cushing's syndrome" (SCS). This term is used to describe autonomous cortisol secretion in patients who don't have the typical signs and symptoms of hypercortisolism. The optimal strategy for identification and management of SCS is unknown; the standard biochemical tests used to screen for overt Cushing's syndrome are generally ill-suited to the assessment of patients who have no, or only very mild signs of cortisol excess, then many tests aimed to study the hypothalamus-pituitary-adrenal axis (HPA) axis do not have sufficient sensitivity to recognize very mild degree of cortisol excess. An increased frequency of hypertension, central obesity, impaired glucose tolerance or diabetes, hyperlipemia and osteoporosis has been described in patients with SCS since patients are exposed to a chronic albeit slight, cortisol excess; however, there is not evidence-based demonstration of long term complications and, consequently, the management of this condition is largely empirical. Adrenalectomy or medical management of associated disease has been indicated as therapeutic options due to lack of data demonstrating the superiority of a surgical or non-surgical treatment.

Subclinical Cushing's syndrome: definition and management

Subclinical Cushing's syndrome is an ill-defined endocrine disorder that may be observed in patients bearing an incidentally found adrenal adenoma. The concept of subclinical Cushing's syndrome stands on the presence of ACTH-independent cortisol secretion by an adrenal adenoma, that is not fully restrained by pituitary feed-back. A hypercortisolemic state of usually minimal intensity may ensue and eventually cause harm to the patients in terms of metabolic and vascular diseases, and bone fractures. However, the natural history of subclinical Cushing's syndrome remains largely unknown. The present review illustrates the currently used methods to ascertain the presence of subclinical Cushing's syndrome and the surrounding controversy. The management of subclinical Cushing's syndrome, that remains a highly debated issue, is also addressed and discussed. Most of the recommendations made in this chapter reflects the view and the clinical experience of the Authors and are not based on solid evidence.

Clinical review: Diagnosis and treatment of subclinical hypercortisolism

CONTEXT

Subclinical hypercortisolism (SH) is a condition of biochemical cortisol excess without the classical signs or symptoms of overt hypercortisolism. It is thought to be present in the 5-30% of patients with incidentally discovered adrenal mass (adrenal incidentalomas), which in turn are found in 4-7% of the adult population. Therefore, SH has been suggested to be present in 0.2-2.0% of the adult population. Some studies suggested that this condition is present in 1-10% of patients with diabetes or established osteoporosis. The present manuscript reviews the literature on diagnostic procedures and the metabolic effect of the recovery from SH.

EVIDENCE ACQUISITION

A PubMed search was used to identify the available studies. The most relevant studies from 1992 to November 2010 have been included in the review.

EVIDENCE SYNTHESIS

The available data suggest that SH may be associated with chronic complications, such as hypertension, diabetes mellitus, overweight/obesity, and osteoporosis. The available intervention studies suggest that the recovery from SH may lead to the improvement of hypertension and diabetes mellitus. A retrospective study suggests that this beneficial effect could be predicted before surgery.

CONCLUSIONS

SH is suggested to be associated with some chronic complications of overt cortisol excess. Recovery from this condition seems to improve these complications. However, a large, prospective, randomized study is needed to confirm this hypothesis and to establish the best diagnostic approach to identify patients with adrenal incidentalomas who can benefit from surgery.

Long-term morphological, hormonal, and clinical follow-up in a single unit on 118 patients with adrenal incidentalomas

OBJECTIVE

To evaluate long-term morphological, functional, and clinical outcome in adrenal incidentalomas.

DESIGN AND METHODS

A total of 118 patients (77 F and 47 M; age 62.3+/-1.0 years) with adrenal incidentalomas were evaluated at baseline and followed-up for median 3 years (range 1-10 years) by clinical, biochemical, hormonal, and morphological evaluation. Among them, six patients with diagnosis of subclinical Cushing's syndrome (SCS) underwent surgery.

RESULTS

At entry, 86% (n=102) of tumors were nonfunctioning (NF) and 14% (n=16) showed SCS. Comparing NF with SCS patients, a significantly higher percentage of dyslipidemia was found in the group of SCS patients (50 vs 23%, P=0.033). During follow-up, adrenal function remained normal in all NF patients, none of them developed subclinical or overt endocrine disease. The cumulative risk of mass enlargement was globally low (25%), but progressive up to 8 years. SCS was confirmed in all patients, and none of them shifted to overt Cushing's syndrome. The cumulative risk of developing metabolic-cardiovascular abnormalities was globally low (22%), but progressive up to 8 years and new diseases were recorded in the group of NF patients only (three patients with dyslipidemia, four with impaired fasting glucose/impaired glucose tolerance, and three with diabetes mellitus). SCS patients who underwent surgery did not show any significant clinical improvement.

CONCLUSIONS

The risk of mass enlargement, hormonal, and metabolic impairment over time is globally low. Conservative management seems to be appropriate, but further prospective studies are needed to establish the long-term outcome of such patients, especially for metabolic status, cardiovascular risk profile and their relationship with endocrine function.

Two-year follow-up of thirty-two non-functional benign adrenal incidentalomas

OBJECTIVE

To evaluate the risk of developing endocrine hyperactivity and carcinoma during a period of up to 5 yr in patients with apparently benign and non-functioning adrenal incidentalomas.

PATIENTS AND METHODS

Thirty-two patients (mean age: 57.0+/-8.3 yr) were investigated in a prospective follow-up study for a median time of 24 months. Twenty-eight patients had unilateral and 4 had bilateral masses. Initial average mass diameter was 17.47+/-6.60 mm. All patients were followed up yearly by physical examination, metabolic parameters, hormonal evaluation [morning cortisol after 3-mg dexamethasone suppression, urinary metanephrines, and upright aldosterone/ plasma renin activity (PRA)].

RESULTS

Among the clinical characteristics, 48% of patients were obese, 20% were hypertensive, 13 had Type 2 diabetes and impaired glucose tolerance. During follow-up period no significant change in the functional status was observed and nomalignant transformation occurred. Only 1 patient developed subclinical Cushing's syndrome at the end of the 1st year and referred to surgery. Change in mass size was correlated with homeostasis model assessment of insulin resistance (p=0.002), upright aldosterone/ PRA (p=0.041), cortisol after dexamethasone suppression (p=0.048) and 24-h urinary normetanephrine (p=0.005) levels. Gender, body mass index, glucose metabolism, and blood pressure were not found to be correlated with change in mass size and functional status.

CONCLUSIONS

Due to the extremely low risk of developing malignancy during up to 5 yr of follow-up, conservative approach for the management of adrenal incidentalomas is thought to be appropriate. However, possibility of evolution to hormonal hypersecretion makes long-term follow-up of 2-to-5 yr seems to be obligatory.

Precocious pubarche: distinguishing late-onset congenital adrenal hyperplasia from premature adrenarche

CONTEXT

Because precocious pubarche (PP) reveals late-onset congenital adrenal hyperplasia (LO-CAH) in 5 to 20% of cases, an adrenal stimulation test is recommended in all patients presenting with it. This test is stressful and expensive, and results are normal in more than 80% of cases.

OBJECTIVE

Our objective was to identify clinical and plasma predictors of LO-CAH among patients presenting with PP.

DESIGN, SETTING, AND PATIENTS

We conducted a retrospective cohort study that included all patients seen for PP at our hospital between 1999 and 2006 (n = 238). All had undergone an ACTH test.

MAIN OUTCOME MEASURE

LO-CAH was defined by a post-ACTH 17-hydroxyprogesterone (17-OHP) plasma level greater than 10 ng/ml and confirmed by mutational analysis of the CYP21 gene. The association of standard clinical and laboratory indicators with LO-CAH was assessed.

RESULTS

Ten (4%) of 238 patients had LO-CAH. Basal 17-OHP, Delta4-androstenedione, and testosterone plasma levels were significantly higher in these patients. A 2-ng/ml threshold for basal 17-OHP plasma levels offered 100% (95% CI, 69-100) sensitivity for the diagnosis of LO-CAH and 99% (95% CI, 96-100) specificity.

CONCLUSION

We identified three plasma predictors of LO-CAH in patients presenting with PP. A selective strategy based on a 2-ng/ml basal 17-OHP plasma level threshold would have safely avoided 99% of the unnecessary ACTH tests among our patients.

Hormonal activity of adrenal incidentalomas: results from a long-term follow-up study

OBJECTIVE

To investigate the natural course of apparently benign adrenal incidentalomas with no overt hyperfunction at diagnosis, as their clinical significance and appropriate management are still controversial.

DESIGN

Prospective long-term follow-up study of patients with adrenal incidentalomas with periodic hormonal and morphological evaluation.

PATIENTS AND METHODS

A total of 77 patients with incidental adrenal masses, diameter 1.0-6.0 cm (median 2.5 cm), were submitted to a hormonal assessment of adrenal function at diagnosis. This was repeated, together with an adrenal CT scan, 12 months later and then every 12-24 months, for a period of 12-154 months (mean 62.7 +/- 31.9, median 60.0).

RESULTS

At diagnosis, 57 patients had normal adrenal function and 20 had subclinical Cushing's syndrome. During follow-up, adrenal function remained normal in 49 patients, subclinical Cushing's syndrome was confirmed in 12, whilst intermittent subclinical autonomous cortisol hypersecretion was found in 12 patients. Overt endocrine disease was diagnosed in 4 patients (Cushing's syndrome in 2 and phaeochromocytoma in 2). A change in mass size (> or = 0.5 cm) was observed in 26 patients (enlargement in 20--including patients who developed overt hyperfunction--with no signs of malignancy and reduction in size in 6).

CONCLUSIONS

Subclinical autonomous cortisol hypersecretion is the most frequent hormonal abnormality in patients with adrenal incidentalomas, and may be intermittent in a significant percentage of cases. Few patients develop overt endocrine disease. A growth tendency is observed in some adrenal incidentalomas without evidence of malignant transformation and occasionally can be related to development of overt hyperfunction. These findings indicate the need for periodic hormonal and morphological evaluation for several years.

Adrenal incidentaloma: clinical characteristics and comparison between patients with and without extraadrenal malignancy

Adrenal incidentaloma (AI) is frequently found in patients with a history of malignancy and, as such, is not always considered a true incidental finding.

OBJECTIVE

To compare the short-term clinical and biochemical behavior of adrenal incidentalomas between oncology and non-oncology patients.

DESIGN

Retrospective comparative case series of 100 consecutive patients with adrenal incidentaloma, followed from 1995 to 2005 in the endocrinology clinic of a tertiary university medical center.

MAIN OUTCOME

A history of malignancy was present in 32 patients. Median follow-up was 24 months. Mean tumor size was 24+/-10 mm. Endocrine evaluation yielded functional abnormalities in 12.2% (subclinical Cushing's 7.4%, Cushing's syndrome 1.1%, hyperaldosteronism 1.3%, pheochromocytoma 3.6%). During follow-up, adrenal function remained unchanged in all patients, but tumor growth was seen in 12.5%. Compared to the non-oncology patients, the oncology group had a higher mean age (67.5+/-9.6 vs 59.4+/-1.3 yr, p=0.001) and greater tumor growth (23.3% vs 7%, p=0.035), with no significant differences for tumor size, functional abnormalities, and extent of change in tumor size. Surgery was performed in 9 patients (3 oncologic) and revealed metastasis in one. None of the other patients had clinical or radiological findings suggesting adrenal malignancy.

CONCLUSION

Our study suggests a similar clinical behavior of adrenal incidentaloma in oncology and non-oncology patients. More studies are needed to assist clinicians in selecting oncology patients with AI for whom a more conservative approach can be recommended.

Incidentally discovered masses in hypertensive patients

Endocrine hypertension is a term used for states in which hormone derangements result in clinically significant hypertension. The adrenal glands are the most likely culprits, due either to an excessive production of mineralocorticoids, catecholamines or glucocorticoids. The term 'adrenal incidentaloma' indicates an adrenal mass discovered accidentally during testing or treatment for other clinical conditions unrelated to any suspicion of adrenal disease. In particular, when an adrenal mass is discovered in a hypertensive subject, physicians must check whether the patient has pheochromocytoma, glucocorticoid excess or primary aldosteronism. Although most adrenal masses are non-hypersecretory adenomas, hormone screening can reveal a significant number of cases of clinically unsuspected hormone-secreting adrenal tumors. If the clinical history or physical examination of a patient with unilateral incidentaloma shows signs and symptoms suggestive of glucocorticoid, mineralocorticoid, adrenal sex hormone or catecholamine excess, which is confirmed biochemically, the treatment of choice is often adrenalectomy. In cases where surgery is contraindicated or the lesions are unresectable, medical treatment may be an option.

Endogenous subclinical hypercortisolism: Diagnostic uncertainties and clinical implications

Subclinical hypercortisolism (SH) is a newly characterized hormonal disorder that is almost exclusively detected in the context of incidentally discovered adrenal masses. The diagnostic criteria used for the definition of this condition are at present controversial. Amongst the various tests used for the detection of this abnormality (dexamethasone suppression, urinary free cortisol, ACTH levels, midnight serum or salivary cortisol concentrations, ACTH responses to CRH stimulation), the dexamethasone suppression tests (DST) seem to better accomplish the task of unmasking subtle abnormalities of cortisol secretion. Several versions of DST have been used: the 1-mg overnight, the 3-mg overnight and the classical 2-day low-dose DST. This latter test has the theoretical advantage that, by more efficiently suppressing pituitary ACTH secretion, it may provide a measure of the residual (ie non- ACTH-dependent) cortisol secretion from the adrenal mass. In this way, post-dexamethasone cortisol concentrations may quantify the degree of autonomous cortisol hypersecretion. In fact, post-dexamethasone cortisol concentrations have a negative correlation with basal ACTH levels and a positive correlation with midnight cortisol concentrations as well as the size of the incidentally discovered adrenal mass. Most of the existing data indicate that SH detected in the context of adrenal incidentalomas may have some clinically significant implications. In fact, patients with higher post-dexamethasone cortisol concentrations demonstrate higher lipid levels and lower bone mass densities. It has also been suggested that SH may be responsible for biochemical and phenotypic changes reminiscent of the metabolic syndrome. In summary, SH does exist and is associated with a negative impact in patients' health; however, hormonal cut-off criteria for decision-making remain to be defined.

Adrenal incidentaloma - follow-up results from a Swedish prospective study

OBJECTIVES

To examine the risk of developing adrenal carcinomas and clinically overt hypersecreting tumours during short-term follow-up in patients with adrenal incidentalomas.

DESIGN

229 (98 males and 131 females) patients with adrenal incidentalomas were investigated in a prospective follow-up study (median time 25 months; range 3-108 months). The patients were registered between January 1996 and July 2001 and followed until December 2004. Twenty-seven Swedish hospitals contributed with follow-up results.

METHODS

Diagnostic procedures were undertaken according to a protocol including reinvestigation with computed tomography scans after 3-6 months, 15-18 months and 27-30 months, as well as hormonal evaluation at baseline and after 27-30 months of follow-up. Operation was recommended when the incidentaloma size increased or if there was a suspicion of a hypersecreting tumour.

RESULTS

The median age at diagnosis of the 229 patients included in the follow-up study was 64 years (range 28-84 years) and the median size of the adrenal incidentalomas when discovered was 2.5 cm (range 1-8 cm). During the follow-up period, an increase in incidentaloma size of > or =0.5 cm was reported in 17 (7.4%) and of > or =1.0 cm was reported in 12 (5.2%) of the 229 patients. A decrease in size was seen in 12 patients (5.2%). A hypersecreting tumour was found in 2% of the hormonally investigated patients: Cushing's syndrome (n = 2) and phaeochromocytoma (n = 1). Eleven patients underwent adrenalectomy, but no cases of primary adrenal malignancy were observed.

CONCLUSIONS

Patients with adrenal incidentaloma had a low risk of developing malignancy or hormonal hypersecretion during a short-term follow-up period.

Adrenal incidentaloma: the influence of a decision-making algorithm on the short-term outcome of laparoscopy

BACKGROUND

At the present time, the precise indications for laparoscopic surgery of adrenal incidentaloma (AI) have yet to be completely clarified. The most controversial issue is the role of laparoscopy in the treatment of potentially malignant and large adrenal masses. Trying to address these questions, we retrospectively examined a group of patients with AIs.

MATERIALS AND METHODS

Forty-two patients with AIs who were laparoscopically treated since 1995 were enrolled in this study. The patients were divided into two groups: the 27 patients of the immediate surgery (IS) group were operated on immediately, whereas the 15 subjects in the delayed surgery (DS) group needed further evaluations and/or a follow-up period before surgery. Surgical timing for both groups was decided according to a widely accepted decision-making algorithm. Many outcome parameters of laparoscopy (operative time, blood loss, conversion rate, time to liquid and solid food nutrition, drainage removal, resumption of normal bowel habits, and average hospital stay) were analyzed in the two groups. The subjects had AIs of various sizes and different histotypes.

RESULTS

Patients in the DS group had a higher risk for malignancy. The definitive pathology revealed a malignant biology in 26.6% of DS vs. 0% of IS cases. No difference in the outcome parameters of laparoscopy was observed between the two groups or among pathologically different AIs. A significant correlation was found between the operative time and the size of the AI (r=0.836, P<0.001, linear regression test).

CONCLUSION

Our study shows that laparoscopy is feasible and safe for AIs, regardless of the preoperative probability of malignancy. The size of the AI was the only determinant for choosing a laparotomy. Further long-term studies are necessary to confirm the laparoscopic efficacy in terms of oncologic safety.

[The use of suprarenal scintigraphy in the differential diagnosis of suprarenal incidentaloma]

OBJECTIVES

To assess the usefulness of adrenal scintigraphy for clinical evaluation of adrenal incidentalomas, and its relation with pathological diagnosis and follow-up.

PATIENTS AND METHODS

We have studied 46 patients with unilateral adrenal incidentaloma of size between 10 and 100 mm (average 30.5 +/- 19 mm). The lesions were discovered with abdominal computerized tomography in the study of a primary tumor (22%) or in the evaluation of benign pathology (78%). Adrenal scintigraphy assessed uptake in adrenal incidentaloma. Hormonal study included urinary catecholamines, plasma cortisol after dexamethasone, adrenal androgens, and renin and aldosterone in hypertensive patients. Five patients were operated, FNAB was carried out in three patients, and in the rest average follow-up was 29 +/- 21 months. Adrenal incidentaloma was considered nonfunctional if the lesion did not modified its size nor showed analytical alterations along a follow-up higher than 8 months.

RESULTS

Of 46 adrenal lesions, seven didn't show uptake (three metastases, one cyst, one adrenal carcinoma, one pheochromocytoma, and one angiomyolipoma), 34 showed excessive uptake (29 nonfunctional adrenal nodules and 5 hyperfunctional adrenal nodules), and five had normal uptake (nonfunctional adrenal nodules). Adrenal scintigraphy was compatible in all cases with cytological study or the response to chemotherapy. Along the follow-up, growth of the lesion was demonstrated in 23%, and reduction or disappearance of the lesion in 11%, with no hormonal significant changes.

CONCLUSIONS

Detection of a lesion with no uptake in adrenal scintigraphy forces to carry out complementary explorations in order to rule out malignant pathology. A lesion with excessive uptake is indicative of a benign process and should be assessed with hormonal determinations.

Subclinical Cushing's syndrome in adrenal incidentalomas

This article reviews the available evidence on subclinical Cushing's syndrome in patients who have adrenal incidentalomas. The authors' aim is to present up-to-date information on the most relevant issues of subclinical Cushing's syndrome by addressing the many uncertainties and controversies surrounding this ill-defined endocrine condition.

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 1 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.

Long-term morphological and hormonal follow-up in a single unit on 115 patients with adrenal incidentalomas

We investigated the natural course of adrenal incidentalomas in 115 patients by means of a long-term endocrine and morphological (CT) follow-up protocol (median 4 year, range 1–7 year). At entry, we observed 61 subclinical hormonal alterations in 43 patients (mainly concerning the ACTH–cortisol axis), but confirmatory tests always excluded specific endocrine diseases. In all cases radiologic signs of benignity were present. Mean values of the hormones examined at last follow-up did not differ from those recorded at entry. However in individual patients several variations were observed. In particular, 57 endocrine alterations found in 43 patients (37.2%) were no longer confirmed at follow-up, while 35 new alterations in 31 patients (26.9%) appeared de novo. Only four alterations in three patients (2.6%) persisted. Confirmatory tests were always negative for specific endocrine diseases. No variation in mean mass size was found between values at entry (25.4±0.9 mm) and at follow-up (25.7±0.9 mm), although in 32 patients (27.8%) mass size actually increased, while in 24 patients (20.8%) it decreased. In no case were the variations in mass dimension associated with the appearance of radiological criteria of malignancy. Kaplan–Meier curves indicated that the cumulative risk for mass enlargement (65%) and for developing endocrine abnormalities (57%) over time was progressive up to 80 months and independent of haemodynamic and humoral basal characteristics. In conclusion, mass enlargement and the presence or occurrence over time of subclinical endocrine alterations are frequent and not correlated, can appear at any time, are not associated with any basal predictor and, finally, are not necessarily indicative of malignant transformation or of progression toward overt disease.

The clinically inapparent adrenal mass: update in diagnosis and management

Clinically inapparent adrenal masses are incidentally detected after imaging studies conducted for reasons other than the evaluation of the adrenal glands. They have frequently been referred to as adrenal incidentalomas. In preparation for a National Institutes of Health State-of-the-Science Conference on this topic, extensive literature research, including Medline, BIOSIS, and Embase between 1966 and July 2002, as well as references of published metaanalyses and selected review articles identified more than 5400 citations. Based on 699 articles that were retrieved for further examination, we provide a comprehensive update of the diagnostic and therapeutic approaches focusing on endocrine and radiological features as well as surgical options. In addition, we present recent developments in the discovery of tumor markers, endocrine testing for subclinical disease including autonomous glucocorticoid hypersecretion and silent pheochromocytoma, novel imaging techniques, and minimally invasive surgery. Based on the statements of the conference, the available literature, and ongoing studies, our aim is to provide practical recommendations for the management of this common entity and to highlight areas for future studies and research.

Subclinical Cushing's syndrome

Clinically inapparent adrenal masses, or adrenal incidentalomas, are discovered inadvertently in the course of workup or treatment of unrelated disorders. Cortical adenoma is the most frequent type of adrenal incidentaloma accounting for approximately 50% of cases in surgical series and even greater shares in medical series. Incidentally discovered adrenal adenomas may secrete cortisol in an autonomous manner, that is not fully restrained by pituitary feed-back, in 5 to 20% of cases depending on study protocols and diagnostic criteria. A number of different alterations in the endocrine tests aimed to assess the function of the hypothalamic-pituitary-adrenal axis has been demonstrated in such patients. This heterogeneous condition has been termed as subclinical Cushing's syndrome, a definition that is more accurate than preclinical Cushing's syndrome since the evolution towards clinically overt hypercortisolism does occur rarely, if ever. The criteria for qualifying subclinical cortisol excess are controversial and we presently do not have sufficient evidence to define a gold standard for the diagnosis of subclinical Cushing's syndrome. An increased frequency of hypertension, central obesity, impaired glucose tolerance, diabetes and hyperlipoproteinemia has been described in patients with subclinical Cushing's syndrome; however, there is not evidence-based demonstration of its long-term complications and, consequently, the management of this condition is largely empirical. Either adrenalectomy or careful observation associated with treatment of metabolic syndrome has been suggested as treatment options because data are insufficient to indicate the superiority of a surgical or nonsurgical approach to manage patients with subclinical hyperfunctioning adrenal cortical adenomas.

Mini review: surgical indications for adrenal incidentaloma

The detection of an adrenal mass as an incidental finding has become so frequent that this trend is considered to be an endocrine epidemic. In these adrenal incidentalomas, a difficult problem is to distinguish between benign and malignant primary or secondary tumors. Another major problem in the management of patients with incidentally discovered adrenal mass is whether and when the mass puts the patient at increased risk of an adverse outcome. A Japanese government-supported study conducted by Professor Miyachi's research committee reviewed the records of all university hospitals and hospitals possessing more than 200 beds in Japan and found 2106 Japanese patients with adrenal incidentaloma during the year 1999. They comprised 1095 males (52%) and 1011 females (48%), mostly distributed between 50 and 59 years of age. The tumor size ranged mostly from 1.1 to 2.0 cm. Almost half (50.3%) of all the incidentalomas were diagnosed as non-functional adenomas, and 5.6% were primary or secondary malignant tumors. In conclusion, accurate assessment of tumor size is an important consideration during preoperative evaluation of adrenal tumors in order to rule out malignancy. Careful evaluation of endocrine functions of the hypothalamic-pituitary-adrenal axis is necessary before surgical treatment in patients with adrenal incidentaloma. Patients with adrenal incidentaloma should be carefully followed, especially regarding size and hormonal conditions.