Diagnostic puzzle of the adrenal "incidentaloma"

The urinary steroid profile in patients diagnosed with adrenal incidentaloma

OBJECTIVE

The aim of this study was to investigate the possible urinary markers of hormonal activity in patients with non-functioning adrenal incidentalomas. In order to evaluate the endocrine activity of aforementioned tumours, urinary steroid metabolite levels were analyzed in samples from patients and controls. Possible blocks in metabolic pathways of the examined hormones were determined by comparing selected urinary steroid metabolite sums and ratios in both groups of interest.

DESIGN

Urine samples were collected from 20 patients with non-functioning adrenal incidentalomas and from 25 controls matched in terms of age, sex and BMI. Excretion of 19 major urinary steroid metabolites was analyzed by gas chromatography. The results were subjected to statistical analysis.

RESULTS

In patients with adrenal incidentalomas sum of total urinary cortisol metabolites was significantly increased in respect to the control group. We also observed a shift towards tetrahydrocorticosterone, cortisol and etiocholanolone production in patients. No significant differences in production of other urinary steroid metabolites were noted in patients with adrenal incidentalomas in respect to control group.

CONCLUSIONS

Our data suggests that not only urinary free cortisol but also its metabolite such as tetrahydrocortisol and other steroids including etiocholanolone and corticosterone tetrahydrometabolite might be urinary markers for the endocrine activity of adrenal incidentalomas. Enhanced levels of these urinary steroid metabolites indicate an impairment of 11beta-hydroxysteroid dehydrogenase activity and slightly increased activity of 5beta-reductase in patients with adrenal incidentalomas.

Laparoscopic Adrenal Surgery: New Frontiers

After about 10 years of experience, laparoscopic adrenalectomy has become the gold standard for the treatment of adrenal lesions. Here, we describe the presenting features, imaging methods, and current surgical approaches to diseases of the adrenal gland. There is general agreement on the suitability of the laparoscopic approach for benign adrenal lesions, but controversy exists about using laparoscopy for suspected adrenal malignancy, metastasis, and partial adrenalectomy. This article reviews the literature on laparoscopic adrenalectomy. In particular, we focus our attention on the new surgical approaches to the gland. We evaluate the indications, operative techniques, and tools for partial adrenalectomy, and we discuss new surgical strategies such as cryosurgery and radiofrequency ablation.

[Contribution of the scintigraphy with iodocholesterol (I-COL) to the diagnosis and characterization of silent adrenal masses]

OBJECTIVE

To assess the role of the adrenal cortical scintigraphy with 131-I Norcholesterol (I-COL) in the diagnosis and characterization of silent adrenal masses.

METHODS

We selected 57 patients who underwent an adrenal scintigraphy with I-COL, 36 women and 21 men (mean aged: 62.5 years), and who were classified into two groups: Group I or Incidentalomas, 39 patients without signs or symptoms of adrenal disease in whom an adrenal mass is incidentally discovered during a CT or ultrasound scan; and a second group or Group II, 18 patients with history of cancer in whom an adrenal mass is discovered. We defined the following Scintigraphic patterns in relationship with the CT: Normal, concordant unilateral (CU) or exclusive; discordant unilateral (DU); concordant asymmetrical (CA) or prevalent; discordant asymmetrical (DA) and nonvisualization (NV). The final diagnosis was obtained with clinical, analytical, and radiological evaluation and in some cases surgery.

RESULTS

In Group I, the diagnoses were: 17 adrenal masses without criteria of malignancy or hormonal overproduction (the Scintigraphic patterns were 10 CA, 5 normal and 2 CU), 9 Subclinical Cushing's syndrome (4 CU, 4 CA and 1 normal), 5 adenomas (all CU), 3 adrenal primary carcinomas, with no uptake in the scintigraphy, and 5 were other diagnoses. In group II, 14 patients had benign masses (all patterns were normal or concordant) and 4 patients metastases (3 discordant and 1 NV patterns). The follow-up time was at least one year.

CONCLUSIONS

The adrenal cortical scintigraphy with I-COL provides us information on the functional status of silent adrenal masses and it is an useful tool to distinguish benign from malignant lesions; for this reason we considered that it must be integrated in the diagnostic algorithm as a complement to other techniques.

Prevalence of subclinical Cushing's syndrome in 70 patients with adrenal incidentaloma: clinical, biochemical and surgical outcomes

Subclinical Cushing's syndrome (SCS) is being detected with increased frequency in patients with adrenal incidentaloma. In the current study, we evaluated the prevalence of SCS in 70 patients with adrenal incidentaloma and compared the main findings on them with other patients with nonfunctional adrenal incidentaloma (NFA). Overnight 3 mg dexamethasone (DXM) suppression test to exclude cortisol hypersecretion, and high dose DXM suppression test to find out patients with SCS, were applied to all subjects. Afterwards, biochemical and clinical findings of patients with SCS were compared with the other patients with NFA. Four of the 70 patients with adrenal incidentaloma were found to have SCS, with a prevalence of 5.7%. Basal ACTH and DHEA-S levels were significantly lower (p < 0.05 and p < 0.01, respectively), and midnight cortisol and 24-hour urinary free cortisol levels were significantly higher in patients with SCS (p < 0.001 and p < 0.05, respectively). Biochemical and metabolic bone parameters were similar in patients with SCS and in patients with NFA. Hypertension, diabetes mellitus, and obesity were more common in patients with SCS. One of the patients with SCS developed adrenocortical insufficiency following unilateral adrenalectomy which lasted for about 6 months. Suppressed ACTH and DHEA-S levels, and high midnight cortisol levels may be some clues for SCS in patients with adrenal incidentaloma. Since patients with SCS frequently have risk factors for atherosclerosis such as hypertension, diabetes, and obesity, and the surgical management of SCS with adrenalectomy may offer an advantage. Patients undergoing adrenalectomy should be followed for the development of adrenal insufficiency.

Adrenal incidentaloma--experience of a standardized diagnostic programme in the Swedish prospective study

OBJECTIVE

To report the 5-year experience of a diagnostic programme for adrenal incidentaloma with special emphasis to diagnose hormonally active and malignant lesions.

DESIGN

A prospective study in which new cases of adrenal incidentalomas in Sweden have been evaluated by a standardized diagnostic protocol between January 1996 and July 2001.

SETTING

Thirty-three different Swedish hospitals have contributed with cases.

SUBJECTS

A total of 381 patients (217 females, 164 males) with adrenal incidentalomas were studied.

INTERVENTIONS

Diagnostic procedures were undertaken according to a standardized programme. Operation was recommended if the incidentaloma had a size of more than 3-4 cm or if there was a suspicion of a hypersecreting tumour.

MAIN OUTCOME MEASURES

The size of the incidentaloma, clinical characteristics of the patients and results of biochemical diagnostic tests were registered.

RESULTS

The median age of the patients was 64 years (18-84 years), and the median size of the incidentalomas was 3 cm (1-20 cm). A total of 85(22%) patients were operated. Twenty of these patients were diagnosed with a benign hypersecreting tumour and 14 with a malignant tumour. Fourteen of 15 operated patients with diagnosed pheochromocytoma had elevated 24-h urinary noradrenaline and all of the patients operated because of a biochemical suspicion of aldosterone or cortisol hypersecretion (n = 6) were found to have adrenal adenomas. Of the 14 operated patients with malignant diseases, 10 were adrenal carcinomas (median size 10 cm; range 4-16 cm). In a multiple logistic regression model, incidentaloma size was significantly associated with the risk of a malignant tumour (P = 0.009), and there was a tendency of an association between age/male sex and the risk of a malignancy (both, P = 0.07).

CONCLUSION

In this Swedish multicentre study of 381 cases with adrenal incidentalomas, 5% had benign hypersecreting tumours and nearly 4% had malignant tumours. The results of the biochemical diagnostic tests used had a high compatibility with the histological diagnosis found at operation in the patients with hypersecreting tumours. Tumour size, male gender and high age were predictive for the risk of a malignant tumour. A follow-up of the patients is warranted in order to establish whether there are undiscovered cases of malignant or hypersecreting tumours amongst the nonoperated patients.

Metabolism of glucocorticoids and mineralocorticoids in patients with adrenal incidentalomas

BACKGROUND

Adrenal incidentalomas are mostly nonfunctioning adrenocortical adenomas (NFI). However, in 5%-12% of the patients a preclinical Cushing's syndrome (PCS) with autonomous cortisol production by the tumour is present. Since urinary free cortisol excretion is not sensitive enough to determine subclinical hypercortisolism, in the present study more sensitive indicators of daily cortisol production were measured.

DESIGN

(1) Tetrahydrocortisol, tetrahydrocortisone, urinary free cortisone together with urinary free cortisol were measured in 35 patients with adrenal incidentalomas (29 NFI and six PCS) and in 35 healthy controls. (2) Since little is known about daily aldosterone production, aldosterone metabolite excretions were measured. (3) As recently reported, ACTH stimulation revealed an increased response of precursors of the glucocorticoid and mineralocorticoid pathway. To find out which steroidogenic enzymes have altered activities, a 1-24ACTH stimulation test (250 microg i.v.) was carried out in 25 patients and 18 healthy controls with determination of multiple steroids. (4) Finally, since it was assumed that 21-hydroxylase deficiency or even 11b-hydroxylase deficiency may be involved in adrenal tumourigenesis, the prevalence of germline CYP21B and CYP11B1 mutations were studied in the same patients, who had underwent the ACTH stimulation test.

RESULTS

(1) Glucocorticoid metabolites were within the normal range in all but three patients with NFI. As a group, the patients had subtle alterations in cortisol metabolism. Tetrahydrocortisol excretion was elevated in NFI and PCS compared with normal subjects (2.1 +/- 0.2 and 2.5 +/- 0.5 vs. 1.5 +/- 0.1 mg 24 h(-1); P < 0.05). Accordingly, the twofold elevation of the tetrahydrocortisol/free cortisol ratio indicates an increased 5beta-reduction of cortisol in the liver. (2) Tetrahydroaldosterone and aldosterone-18-glucuronide excretions were not different to controls. (3) In patients with incidentalomas an increased response to ACTH was seen for 17-hydroxyprogesterone (595 +/- 133 vs. 160 +/- 25 ng dL(-1)), 21-desoxycortisol (105 +/- 25 vs. 29 +/- 9 ng dL(-1)) and 11-desoxycortisol (401 +/- 40 vs. 293 +/- 17 ng dL(-1)). (4) In only one of 25 patients, a heterozygous deletion in exon 3 of the CYP21B gene was detected.

CONCLUSIONS

(1) In conclusion, even the excretion of the main glucocorticoid metabolites is not a marker sensitive enough to distinguish between NFI and PCS. However, it is also possible that alterations in cortisol secretion are qualitative rather than quantitative. (2) Zona glomerulosa function is not influenced. (3) The elevation of 21-desoxycortisol argues against an impairment of 11beta-hydroxylase and favours a decreased activity of 21-hydroxylase. All others had wild-type sequences of both genes. (4) In conclusion, neither 21-hydroxylase deficiency nor 11beta-hydroxylase deficiency are predisposing factors for adrenal tumourigenesis.

Subclinical Cushing's syndrome in patients with adrenal incidentaloma: clinical and biochemical features

Incidentally discovered adrenal masses are mostly benign, asymptomatic lesions, often arbitrarily considered as nonfunctioning tumors. Recent studies, however, have reported increasing evidence that subtle cortisol production and abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis are more frequent than previously thought. The purpose of this study was to investigate the clinical and hormonal features of patients with incidentally discovered adrenal adenomas, in relation to their clinical outcome. Fifty consecutive patients with incidentally detected adrenal adenomas, selected from a total of 65 cases of adrenal incidentalomas, were prospectively evaluated. All of them underwent abdominal computed tomography scan and hormonal assays of the HPA axis function: circadian rhythm of plasma cortisol and ACTH, urinary cortisol excretion, 17-hydroxyprogesterone, androgens, corticotropin stimulation test and low-dose (2 mg) dexamethasone test. The patients were reevaluated at regular intervals (6, 12, and 24 months) for a median period of 38 months. Subtle hypercortisolism, defined as abnormal response to at least 2 standard tests of the HPA axis function in the absence of clinical signs of Cushing's syndrome (CS), was defined as subclinical CS. Mild-to-severe hypertension was found in 24 of 50 (48%) patients, type-2 diabetes in 12 of 50 (24%), and glucose intolerance in 6 of 50 (12%) patients. Moreover, 18 of 50 patients (36%) were diffusely obese (body mass index, determined as weight/height2, > 25), and 14 patients (28%) had serum lipid concentration abnormalities (cholesterol > or = 6.21 mmol/L, low-density lipoprotein cholesterol > or = 4.14 mmol/L and/or triglycerides > or = 1.8 mmol/L). Compared with a healthy population, bone mineral density Z-score, determined by the DEXA technique, tended to be slightly (but not significantly) lower in patients with adrenal adenoma (-0.41 SD). Endocrine data were compared with 107 sex- and age-matched controls, and patients with adenomas were found to have heterogeneous hormonal abnormalities. In particular, significantly higher serum cortisol values (P < 0.001), lower ACTH concentration (P < 0.05), and impaired cortisol suppression by dexamethasone (P < 0.001) were observed. Moreover, in patients with adenomas, cortisol, 17-OH progesterone, and androstenedione responses to corticotropin were significantly increased (P < 0.001, all), whereas dehydroepiandrosterone sulfate levels were significantly lower at baseline, with blunted response to corticotropin (P < 0.001, both). However, the criteria for subclinical CS were met by 12 of 50 (24%) patients. Of these, 6 (50%) were diffusely obese, 11 (91.6%) had mild-to-severe hypertension, 5 (41.6%) had type-2 diabetes mellitus, and 6 (50%) had abnormal serum lipids. The clinical and hormonal features improved in all patients treated by adrenalectomy, but seemed unchanged in all those who did not undergo surgery (follow-up, 9 to 73 months), except for one, who was previously found as having nonfunctioning adenoma and then revealed to have subclinical CS. In conclusion, an unexpectedly high prevalence of subtle autonomous cortisol secretion, associated with high occurrence of hypertension, diabetes mellitus, elevated lipids, and diffuse obesity, was found in incidentally discovered adrenal adenomas. Although the pathological entity of a subclinical hypercortisolism state remained mostly stable in time during follow-up, hypertension, metabolic disorders, and hormonal abnormalities improved in all patients treated by adrenalectomy. These findings support the hypothesis that clinically silent hypercortisolism is probably not completely asymptomatic.

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.

Management approaches to adrenal incidentalomas. A view from Ancona, Italy

The definition of adrenal incidentaloma encompasses a heterogeneous spectrum of pathologic entities, including primary adrenocortical and medullary tumors, benign or malignant lesions, hormonally active or inactive lesions, metastases, and infections. This article provides an overview of the diagnostic clinical approach and management of the incidentally discovered adrenal masses. Approaches are based on data collected in more than 1000 cases of the Collaborative Study Group on Adrenal Incidentaloma of the Italian Society of Endocrinology and the authors' experience.

Incidentally found adrenocortical carcinoma. A study of 21 patients

The frequency of adrenocortical carcinoma was studied in a group of 311 incidentally discovered adrenal tumours. Clinical characteristics were also analysed. Ultrasound scan and computed tomography were the main imaging techniques used. Hormonal examinations were also carried out. The patients with an adrenal tumour diameter greater than or equal to 4.0 cm, and those with excess steroid production were recommended for surgery. Of 131 patients treated with surgery, adrenocortical carcinoma was diagnosed in 21 cases. The diameter of these tumours ranged between 3.2 and 20.0 cm. The majority of these were hormonally inactive, but, in some cases increased corticosteroid secretion was noted. In 17/21 patients, mitotane was administered following surgery, with a good response in 13 cases. These 21 cases were compared with a group of 51 patients with clinically overt adrenocortical carcinoma.

Tissue remodelling in the adrenal gland

Adaptation of the adrenal gland to the demands of the organism is regulated functionally and structurally. Three common hypotheses on zonation in the adrenal gland, the migrational, zonal, and transformation field theories, try independently to reconcile the findings on structure, proliferation, and cell death. The classical theories on zonation are revisited in the light of recent data on cell death and renewal. In accordance with data on cell death as immunoreactivity against FAS(CD 95), an apoptosis-inducing receptor, in situ end labelling of fragmented DNA, and ultrastructural analyses, programmed cell death (PCD) occurs throughout the whole organ. The angiotensin II receptor subtypes described in the adrenal allow an additional regulation of tissue homeostasis by proliferative and even by the antiproliferative effects of the angiotensin II type 2 receptor. Proto-oncogenes are involved in the regulation of cell cycle and PCD, and adrenocorticotropin asserts its tissue integrating and differentiating effects by regulating proto-oncogenes such as c-jun, c-fos, jun-B and c-myc. Polypeptides involved in proliferation and DNA repair, such as proliferating cell nuclear antigen and Ki-67, have been found within zones of expected cell senescence. The expression of the class II major histocompatibility complex on normal adrenocortical cells allows cell-to-cell communication with the immune system and may trigger the Fas/Fas-ligand system to permit tissue regression and decreasing activity in both systems. In summary, new data allow us to reappraise and to reconcile the classical theories. Apoptosis is a physiological process in the adrenal gland. There is a differential regulation of apoptosis in the different zones. An investigation of this process may elucidate the basic mechanisms of adrenal zonation.

Adrenal incidentalomas. Diagnostic workup of the incidentally discovered adrenal mass

The incidentally discovered adrenal mass is a diagnostic dilemma veterinarians are likely to face with increasing frequency in the coming years. Dogs and cats may be more prone to functional adrenal lesions than are humans. Most adrenal tumors are benign, but a significant number of adrenocortical carcinomas (approximately 12%) and metastatic lesions within the adrenal glands (3% to 34%) do occur. Evaluation for hypertension, hypokalemia, and loss of hypothalamic-pituitary-adrenal responsiveness to a low dose of dexamethasone is appropriate for all patients with adrenal incidentalomas. The value of clinical and historical signs of hormonal overexpression should not be underestimated. More invasive or expensive diagnostic testing should be predicted on suspicions raised by the history and clinical signs. New diagnostic clinicopathologic tests, including plasma CgA and serum DHEAS, should be investigated in veterinary patients. Advanced diagnostic imaging using nuclear scintigraphy and chemical-shift MRI may offer veterinarians sensitive and specific noninvasive tools to consider for the evaluation of these patients. Patients with large masses, tumors with signs of malignancy, or productive adrenal tumors (plus or minus cortisol-producing tumors in which chemical ablation with mitotane can be attempted) should be considered candidates for exploratory surgery.

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.

Anterior, posterior, or laparoscopic approach for the management of adrenal diseases?

BACKGROUND

At the advent of laparoscopic adrenalectomy it seemed timely to us to assess the advantages and the overall results of the different techniques that are currently used in an approach to adrenalectomy.

PATIENTS AND METHODS

Between 1984 and 1995, 165 patients underwent adrenalectomy. Eighty-six patients (37 men and 49 women with a mean age of 46.4 years) underwent adrenalectomy via the anterior approach, 61 patients (18 men and 43 women with a mean age of 43.8 years) underwent posterior extraperitoneal adrenalectomy, and 18 patients (8 men and 10 women with a mean age of 48.7 years) underwent anterior laparoscopic adrenalectomy. For statistical analysis of the different comparisons between the groups we used the t test for independent samples, the Wilcoxon test, chi-square, and one way analysis of variance.

RESULTS

There was no operative mortality. The morbidity was 13.9% in the anterior approach, 9.8% in the posterior approach, and 0% in the laparoscopic approach. The mean operating time for unilateral adrenalectomy was 155.3 min (range 75 to 315) for the anterior approach, 108.6 min (range 60 to 195) for the posterior approach and 116.1 min (range 75 to 180) for the laparoscopic approach. For bilateral adrenalectomy the mean operating time was 165 min for the anterior and 178 min for the posterior approach. The average diameter of tumors resected anteriorly was 8.07 cm (range 2.5 to 20), posteriorly was 5.25 cm (range 0.5 to 14), and laparoscopically was 4.03 cm (range 2 to 6.5). The mean length of postoperative hospitalization for patients undergoing unilateral adrenalectomy was 8 days (range 2 to 25) for the anterior approach, 4.5 days (range 1 to 11) for the posterior approach, and 2.2 days (range 1 to 5) for the laparoscopic approach. Patient controlled analgesia lasted 3.4 days for those operated anteriorly, 2.3 days for those operated posteriorly, and 1.08 days for those that underwent laparoscopic adrenalectomy.

CONCLUSIONS

The laparoscopic approach to the adrenal promises the safest and least painful operation with shorter in-hospital stay and the best cosmetic and long-term results. The posterior approach is the fastest of all and a better overall operation than the anterior approach that should only be reserved for removing very large adrenal tumors and when concomitant intra-abdominal procedures, that can't be handled laparoscopically, are anticipated.