Adrenal incidentalomas: Risk of adrenocortical carcinoma and clinical outcomes

Prognostic significance of immunohistochemical markers in adrenocortical carcinoma

Background: To present basic demographic and clinical characteristics of patients with adrenocortical carcinoma (ACC), to determine the overall survival rate and to analyze the results of immunohistochemical staining and its correlation with the length of survival.Material and methods: The study was conducted during the period between 1996 and 2010 and included 30 patients with ACC. Immunohistochemical staining (MMP9, melan A, inhibin, caltretinin, D2-40, synaptophysin and Ki-67) was performed.Results: ACC was diagnosed in 19 females and 11 men (1.7:1). The average age was 50.1 years. The median tumor size was 10 cm, the median weight 400 g. Majority of subjects had positive immunohistochemical staining for the markers of interest. Patients with any negative staining had shorter cancer-specific survival than ones with positive staining. According to the log-rank test results as well as according to the results of the univariate Cox analysis, negative staining for inhibin, D2-40 and synaptophysin and Ki-67 expression ≥7% were associated with poorer prognosis.Conclusions: The results of our study suggest that the absence of staining for some immunohistochemical markers and increased expression of Ki-67 are associated with a poorer prognosis and shorter survival of patients with ACC. Immunohistochemical markers may serve as a prognostic factor for ACC.

Laparoscopic adrenalectomy

In the last three decades, endoscopic adrenalectomy has become the gold standard for the surgical treatment of most adrenal diseases. Gagner et al., first reported in 1992, the lateral trans-abdominal laparoscopic approach to adrenalectomy. Afterwards, several retrospective and comparative studies addressed the advantages of minimally invasive adrenalectomy specifically consistent in less postoperative pain, improved patients' satisfaction, shorter hospital stay and recovery time when compared to open adrenalectomy. The lateral transabdominal approach to the adrenals is currently one of the most widely used, since it allows an optimal comprehensive view of the adrenal region and surrounding structures, and provides and adequate working space. On the other hand, from a technical point of view, essential requirements for a successful laparoscopic adrenalectomy are an appropriate knowledge of retroperitoneal anatomy, a gentle tissue manipulation and a precise haemostasis technique in order to identify appropriately the structures of interest and avoid the troublesome 'oozing' that could complicate the surgical procedure.

The prognostic significance of adrenocortical carcinomas identified incidentally

BACKGROUND AND OBJECTIVES

Little is known regarding the difference in prognosis among patients who have an incidentally discovered adrenocortical carcinoma (ACC) vs those who present with signs or symptoms. We aimed to explore differences in the outcomes of these two populations.

METHODS

Data were collected on patients who underwent resection of ACC at 1 of 13 institutions between January 1993 and December 2014. Presentations were categorized as incidental vs symptomatic and outcomes were compared.

RESULTS

Among 227 patients, 100 were diagnosed incidentally while 127 patients presented with symptoms/signs. Clinical and pathological features were comparable among incidental vs nonincidental patients with ACC following the exceptions. Patients with incidentalomas were more likely to have a T1/T2 tumor (55.8% vs 34.8%; P < 0.01) and less likely to have a functional tumor (33.7% vs 47.9%; P = 0.04). Patients with an incidental ACC had improved median recurrence-free survival (RFS; 29.4 months) compared with patients with a nonincidental ACC (13.0 months; P = 0.03); however, on multivariable analysis, incidental ACC was not an independent predictor of survival.

CONCLUSIONS

Patients with resected ACC identified incidentally had an improved RFS compared with the patients who presented with symptoms or signs. This difference may be related to the patients with incidental tumors having earlier T-stage disease.

The challenge of developmental therapeutics for adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare disease with an estimated incidence of only 0.7 new cases per million per year. Approximately 30-70% of the patients present with advanced disease with very poor prognosis and without effective therapeutic options. In the recent years, unprecedented progresses in cancer biology and genomics have fostered the development of numerous targeted therapies for various malignancies. Immunotherapy has also transformed the treatment landscape of malignancies such as melanoma, among others. However, these advances have not brought meaningful benefits for patients with ACC. Extensive genomic analyses of ACC have revealed numerous signal transduction pathway aberrations (e.g., insulin growth factor receptor and Wnt/β-catenin pathways) that play a central role in pathophysiology. These molecular alterations have been explored as potential therapeutic targets for drug development. This manuscript summarizes recent discoveries in ACC biology, reviews the results of early clinical studies with targeted therapies, and provides the rationale for emerging treatment strategies such as immunotherapy.

Alveolar echinococcosis of the right adrenal gland: a case report and review of the literature

Background

Extrahepatic manifestations of Echinococcus multilocularis are very rare, especially in the adrenal glands. To the best of our knowledge, only seven cases of adrenal alveolar echinococcosis have been reported, all from the Far East. All of these occurred exclusively in the right adrenal gland.

Case presentation

We report a rare case of an extrahepatic alveolar echinococcosis in an asymptomatic 78-year-old white man with an incidentaloma of his right adrenal gland. After surgical resection and medical treatment with albendazole no recurrence of the disease appeared at 1-year follow-up.

Conclusions

As the occurrence of Echinococcus multilocularis in Europe increases, alveolar echinococcosis should be included in the differential diagnosis of cystic adrenal incidentalomas.

Advances in our understanding of the prognosis of adrenal incidentaloma

As cross-sectional abdominal imaging is used increasingly, adrenal incidentaloma (AI) are being found frequently and present a clinical dilemma. The vast majority are benign and non-functioning, but a minority represent incidentally found functional or malignant tumours. In this review we summarise the current clinical, biochemical and radiological investigation of AI and discuss recent advances that differentiate clinically inconsequential lesions from functional and/or malignant AI. Areas covered: Prevalence, natural history, biochemical and radiological assessment, indications for surgery and surgical provision. Expert commentary: Well established work-up of AI usually enables benign, non-functioning lesions to be differentiated from functioning and/or malignant AI. In indeterminate lesions recent advances in work-up such as urine steroid profiles measured by gas chromatography /mass spectrometry and functional imaging with 18F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) in addition to standard investigations have improved characterisation of these lesions. The management of AI showing mild autonomous hypercortisolism without overt features of Cushing's syndrome remains controversial and is discussed in this review.

5th International ACC Symposium: Imaging for Diagnosis and Surveillance of Adrenal Tumors--New Advances and Reviews of Old Concepts

Adrenocortical carcinoma (ACC) is often diagnosed incidentally. However, significant difficulties persist in diagnosing the rare ACC among the very common benign adrenal tumors, which are present in up to 5% of the population. Due to the very low prevalence of ACC, prospective studies are impossible to conduct. Two recent studies took the approach of reviewing preexisting adrenal tumors prior to the diagnosis of ACC. These data challenge current concepts of diagnosis and surveillance of incidentally discovered masses. Oncocytomas (benign and malignant) represent an entity that can be difficult to be diagnosed by radiographic characteristics and even histologically. However, some recent data provides insight into their appearance in imaging procedures. With regards to ACC specific imaging, which could be applied for differential diagnosis of adrenal tumors, surgery planning and surveillance several radionucleotides have been evaluated over the last decades showing promising results. Of particular interest, these substances can potentially be used for therapy as well.

Clinicopathological Features of Adrenal Tumors: a Ten-year Study in Yazd, Iran

BACKGROUND

Adrenal tumors are relatively uncommon, and have different presentations, so we decided to evaluate the clinico-pathological characteristics of benign and malignant tumors in a ten-year period.

MATERIALS AND METHODS

This cross sectional-analytical study was conducted on adrenal resection samples taken during 2004-2014 in three hospitals in Yazd province. Data were analyzed using SPSS software, version 17. Chi-square and Fisher's exact test were used as appropriate Results: A total of 71 patients with adrenal tumors were analyzed, including 32 (45.1%) men and 39 (54.9%) women with an overall mean age 37.7±19.9 (range: 6-75 years). Some 50.7% of lesions were benign and 49.3% were malignant. Neuroblastoma was the most malignant lesion (32.3%) followed by adrenocortical carcinoma (8.4%). Among the benign lesions pheochromocytoma was the most common (25.3%) followed by adrenocortical adenoma (12.6%). While 64% of tumors were functional 36% were non functional. Significant correlation was seen between the age of patient and type of tumor (P=0.001). In patients between 14-40 years old no malignant lesions was found, although under 14 years old all of the tumors were malignant. Malignant lesions mostly presented with abdominal pain, abdominal mass and anorexia (57.2%, 45.7% and 45.7%) respectively. Benign lesions mostly presented with paroxysmal hypertension, headache and abdominal pain (61.2%, 47.2% and 44.4%) respectively.

CONCLUSIONS

Since the trend of adrenal tumors is on the rise based on this and other studies, suspected cases should undergo prompt hormonal and radiological assessment. Early diagnosis and treatment could prevent tumor progression and reduce mortality and morbidity rates.

What is the appropriate role of minimally invasive vs. open surgery for small adrenocortical cancers?

PURPOSE OF REVIEW

The role of endoscopic adrenalectomy for adrenocortical carcinoma is the most controversial and debated points in adrenal surgery. We reviewed the most recent literature on this topic.

RECENT FINDINGS

From the amount of available data (even if not conclusive), the following could be extrapolated: first, for patients with apparently localized disease the adrenal gland should be removed en bloc with the entire retroperitoneal fat pad, which also includes some periadrenal lymph nodes, but no extended resection is necessary in absence of involvement of adjacent structures; second, in experienced centers, oncologic outcome for endoscopic adrenalectomy is not inferior to open adrenalectomy when strict selection criteria and the principles of oncologic surgery are respected. When performed by nonexperienced surgeons, endoscopic adrenalectomy may be associated with a higher rate of positive margin and local recurrence; third, patients observed at specialized referral centers receive a more accurate preoperative workup that allows a better operative planning and a more comprehensive postoperative treatment.

SUMMARY

Although waiting for further more exhaustive studies, we think that for suspected adrenocortical carcinoma, smaller than 8-10 cm and without pre or intraoperative evidence of local invasion, endoscopic adrenalectomy in a referral center seems to be an acceptable option.

Surgery is associated with improved survival for adrenocortical cancer, even in metastatic disease

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare but lethal tumor. Predictors of survival include earlier stage at presentation and complete operative resection. We assessed effect of treatment and demographic variables on survival.

METHODS

ACC cases were abstracted from the California Cancer Registry and Office of Statewide Health Planning and Development (1999-2008). Predictors included patient demographics, comorbidities, tumor size, stage, and treatment (none, surgery, chemotherapy and/or radiation [CRT], and surgery plus CRT).

RESULTS

We studied 367 patients with median tumor size of 10 cm. At presentation, 37% had localized, 17% had regional, and 46% had metastatic disease. Median survival was 1.7 years (7.4 years local, 2.6 years regional, and 0.3 years metastatic, P < .0001). One-year and 5-year survival was: 92%/62% (local); 73%/39% (regional); and 24%/7% (metastatic). Increased age (hazard ratio [HR] 1.16) and Cushing's syndrome (HR 1.66) worsened survival (P < .05). Low socioeconomic status worsened survival in local and regional disease (P < .05). In multivariable regression, both surgery (regional HR 0.13; metastatic HR 0.52) and surgery plus CRT (regional HR 0.15; metastatic HR 0.31) improved survival compared with no treatment (P < .02).

CONCLUSION

In ACC, surgery is associated with improved survival, even in metastatic disease. Surgery should be considered for select patients as part of multimodality treatment.

A new risk stratification algorithm for the management of patients with adrenal incidentalomas

BACKGROUND

Although adrenal incidentalomas (AI) are detected in ≤5% of patients undergoing chest and abdominal computed tomography (CT), their management is challenging. The current guidelines include recommendations from the National Institutes of Health, the American Association of Endocrine Surgeons (AAES), and the American Association for Cancer Education (AACE). The aim of this study was to develop a new risk stratification model and compare its performance against the existing guidelines for managing AI.

METHODS

A risk stratification model was designed by assigning points for adrenal size (1, 2, or 3 points for tumors <4, 4-6, or >6 cm, respectively) and Hounsfield unit (HU) density on noncontrast CT (1, 2, or 3 points for HU <10, 10-20, or >20, respectively). This model was applied retrospectively to 157 patients with AI managed in an endocrine surgery clinic to assign a score to each tumor. The utility of this model versus the AAES/AACE guidelines was assessed.

RESULTS

Of the 157 patients, 54 (34%), had tumors <4 cm with HU <10 (a score of 2). One third of these were hormonally active on biochemical workup and underwent adrenalectomy. The remaining two thirds were nonsecretory lesions and have been followed conservatively with annual testing. In 103 patients (66%), the adrenal mass was >4 cm and/or had indeterminate features on noncontrast CT (HU >10, irregular borders, heterogeneity), and adrenalectomy was performed after hormonal evaluation was completed (10 were hormonally active on biochemical testing). Seven of these patients (7%) had adrenocortical cancer on final pathology with tumor size <4 cm in 0, 4-6 cm in 1, and >6 cm in 5 patients. Of the hormonally inactive patients, 32% had a score of 3, 38% 4, and 30% 5 or 6. The incidence of adrenocortical cancer in these subgroups was 0, 0, and 25%, respectively.

CONCLUSION

This study shows that an algorithm that utilizes the hormonal activity at the first decision step followed by a consolidated risk stratification, based on tumor size and HU density, has a potential to spare a substantial number of patients from unnecessary "diagnostic" surgery for AI.

Laparoscopic transperitoneal adrenalectomy: Our initial results

OBJECTIVE

To present the first 24 laparoscopic adrenalectomies performed in our clinic because of an adrenal mass.

MATERIAL AND METHODS

The medical files of 24 patients who underwent laparoscopic adrenalectomy between December 2008 and March 2013 at Haseki Teaching and Research Hospital were analyzed retrospectively. The demographic characteristics of the patients were recorded. Lateral transperitoneal laparoscopic adrenalectomy was performed in all patients. The operation time was defined as the interval between the first incision of the skin and closure of the skin. Intraoperative complications, estimated blood loss and hospital stays of the patients were evaluated. Final pathologies were recorded.

RESULTS

The mean age of the patients was 44.2±8.58 years (range: 29-66 years). Nine patients were female and 15 were male. A total of 24 masses were identified in the right (n=11), and left (n=13) adrenal glands masses were identified., Eighteen patients (75%) had no symptoms, and the masses were identified incidentally. The mean operation time was 144±46.1 minutes (range: 90-320 minutes), and the mean blood loss was 74±12.3 mL (range: 50-130 mL). None of the patients required a blood transfusion. In one patient, liver injury was identified intraoperatively due to traction. The mean duration of hospitalization was 2.9±1.1 days (range: 2-5 days). Adrenocortical adenoma and pheochromocytoma were the most common pathologies.

CONCLUSION

Laparoscopic adrenalectomy is a safe and effective method for the treatment of adrenal masses with low complication rates.

Differentially expressed proteins in malignant and benign adrenocortical tumors

We have compared the microsomal protein composition of eight malignant and six benign adrenocortical tumors with proteomic methods. IGF2 had increased level in the malignant tumors, confirming previous microarray studies on the same material. Aldolase A, a glycolytic enzyme, also showed increased levels in the malignant tissue compared to the benign. Additionally, several proteins belonging to complex I in the mitochondrial respiration chain showed decreased levels in the malignant tissue. Taken together, this may indicate a shift in energy metabolism where glycolysis may be favored over tight coupling of glycolysis and mitochondrial respiration, a phenomenon known as the Warburg effect. One of the complex I proteins that showed decreased levels in the malignant tissue was GRIM-19. This protein has been suggested as a tumor suppressive protein by being a negative regulator of STAT3. In summary, an analysis of the microsomal proteome in adrenocortical tumors identifies groups of proteins as well as specific proteins differentially expressed in the benign and malignant forms. These proteins shed light on the biology behind malignancy and could delineate future drug targets.

Preoperative workup in the assessment of adrenal incidentalomas: outcome from 282 consecutive laparoscopic adrenalectomies

Background

To confirm the efficacy of preoperative workup, the authors analyse the results of a multicentre study in a surgical series of patients diagnosed with an adrenal incidentaloma.

Methods

The retrospective review of a prospectively collected database was conducted. The data was obtained by six surgical units operating in the Campania Region, Italy. Five-hundred and six (506) adrenalectomies performed between 1993 and 2011 on 498 patients were analysed. Final histology in patients with a preoperative diagnosis of incidentaloma and studied according to guidelines (230/282 patients group A) was compared with final histology coming from patients presenting the same preoperative diagnosis but studied not according to guidelines (52/282 patients group B).

Results

In group A preoperative diagnosis was confirmed at final histology in 76/81 (93.8%) cases of subclinical functioning lesions presenting as an incidentaloma. The preoperative detection of pheochromocytoma and primary adrenocortical cancer (ACC) reached 91.6% and 84.6% respectively. In group B conversion rate to open surgery was higher than in group A (p = 0.02). One pheochromocytoma was missed at preoperative diagnosis whereas one ACC smaller than 4 centimetres (cm) and coming from an incidental lesion was discovered. In both groups a significant association between increasing dimensions of incidentaloma and cancer has been observed (p = 0.001).

Conclusions

This surgical series confirm the high efficacy of suggested guidelines. A significant preoperative detection rate of adrenal lesions presenting as incidentaloma is observed. The unnecessary number of adrenalectomies performed in understudied patients, causing higher morbidity, was not associated to a higher detection rate of primary adrenocortical cancer.

Functional characterization of adrenal lesions using [123I]IMTO-SPECT/CT

CONTEXT

Adrenal tumors are highly prevalent and represent a wide range of different pathological entities. Conventional imaging often provides only limited information on the origin of these lesions. Novel specific imaging methods are, therefore, of great clinical interest.

OBJECTIVE

We evaluated [(123)I]iodometomidate ([(123)I]IMTO) imaging for noninvasive characterization of adrenal masses.

DESIGN/SETTING

This was a prospective monocentric diagnostic study in a tertiary care center.

PATIENTS AND INTERVENTION

A total of 51 patients with an adrenal lesion underwent [(123)I]IMTO imaging after injection of 185 MBq of [(123)I]IMTO. Sequential planar whole-body scans until 24 hours postinjection and single photon emission computed tomography (SPECT)/computed tomography imaging 4 to 6 hours postinjection were performed.

MAIN OUTCOME MEASURE

Sensitivity and specificity of [(123)I]IMTO imaging for the noninvasive characterization of adrenal lesions were measured.

RESULTS

Adrenocortical tissue showed high and specific tracer uptake with a short investigation time and low radiation exposure. Qualitative analysis of SPECT/computed tomography data resulted in a sensitivity of 89% and a specificity of 85% for differentiating adrenocortical tumors from lesions of nonadrenocortical origin. Receiver-operating characteristic analysis of semiquantitative data revealed a sensitivity of 83% and a specificity of 86% for identification of adrenocortical lesions at a cutoff value of tumor to liver ratio of 1.3.

CONCLUSIONS

[(123)I]IMTO is a highly specific radiotracer for imaging of adrenocortical tissue with a short investigation time and low radiation exposure. Because of the general availability of SPECT technology, [(123)I]IMTO scintigraphy has the potential to become a widely used tool to noninvasively characterize the biology of adrenal lesions.

Risk of concomitant malignancy in hyperfunctioning adrenal incidentalomas

BACKGROUND

Adrenal masses are common incidental findings on radiologic imaging. The association between malignancy and hormonal hyperactivity found in incidentally discovered adrenal tumors, however, remains unclear.

METHODS

A retrospective analysis of prospectively collected data from patients who underwent adrenalectomy for incidentally discovered adrenal tumors at a single institution. Outcomes and operative data were compared by univariate analysis. Area under the curve was used to analyze the effect of tumor size in predicting malignancy.

RESULTS

There were 49 patients who initially presented with adrenal incidentalomas that underwent adrenalectomy. Most patients were Caucasian women with an average age of 51 ± 14 years. Of this group, 24 patients underwent resection for hyperfunctioning adrenal glands. There were no significant differences in malignancy rates between hyperfunctional and nonfunctional tumors (4.1% vs. 12.0%, P = 0.32). On final histopathology, there were four patients with adrenal malignancies: two adrenocortical carcinomas and two metastatic from renal carcinoma. Only one patient with a hyperfunctioning adrenal tumor had underlying malignancy. Overall, invasion of adjacent structures (P < 0.001), presence of lymphadenopathy (P = 0.02), metastasis (P = 0.03), irregular tumor margins (P = 0.01), heterogeneity (P = 0.05), and tumor size >6 cm (P = 0.04) on radiologic imaging were strongly associated with malignancy in adrenal incidentalomas.

CONCLUSIONS

The risk of concomitant malignancy and hormonal hyperactivity in adrenal incidentalomas is very low. Tumor size (>6 cm) and radiographic features remain the most important predictors of adrenal malignancy, regardless of tumor function.

Open versus endoscopic adrenalectomy in the treatment of localized (stage I/II) adrenocortical carcinoma: results of a multiinstitutional Italian survey

BACKGROUND

We compared the oncologic effectiveness of open adrenalectomy and endoscopic adrenalectomy in the treatment of patients with localized adrenocortical carcinoma.

METHODS

One hundred fifty-six patients with localized adrenocortical carcinoma (stage I/II) who underwent R0 resection were included in an Italian multiinstitutional surgical survey. They were divided into 2 groups based on the operative approach (either conventional or endoscopic).

RESULTS

One hundred twenty-six patients underwent open adrenalectomy and 30 patients underwent endoscopic adrenalectomy. The 2 groups were well matched for age, sex, lesion size, and stage (P = NS). The mean follow-up time was similar for the 2 groups (P = NS). The local recurrence rate was 19% for open adrenalectomy and 21% for endoscopic adrenalectomy, whereas distant metastases were recorded in 31% of patients in the conventional adrenalectomy group and 17% in the endoscopic adrenalectomy group (P = NS). The mean time to recurrence was 27 ± 27 months in the conventional open adrenalectomy group and 29 ± 33 months in the endoscopic adrenalectomy group (P = NS). No significant differences were found between the 2 groups in terms of 5-year disease-free survival (38.3% vs 58.2%) and 5-year overall survival rates (48% vs 67%; P = NS).

CONCLUSION

The operative approach does not affect the oncologic outcome of patients with localized adrenocortical carcinoma, if the principles of surgical oncology are respected.

A cost-effectiveness analysis of adrenalectomy for nonfunctional adrenal incidentalomas: is there a size threshold for resection?

BACKGROUND

Adrenocortical carcinoma (ACC) is a rare, but aggressive, malignancy. Current American Association of Clinical Endocrinologists (AACE)/American Association of Endocrine Surgeons (AAES) guidelines recommend resection of nonfunctional adrenal neoplasms ≥ 4 cm. This study evaluates the cost-effectiveness of this approach.

METHODS

A decision tree was constructed for patients with a nonfunctional, 4-cm adrenal incidentaloma with no radiographic suspicion for ACC. Patients were randomized to adrenalectomy, surveillance per AACE/AAES guidelines, or no follow-up ("sign-off"). Incremental cost-effectiveness ratio (ICER) includes health care costs, including missed ACC. ICER (dollar/life-year-saved [LYS]) was determined from the societal perspective. Sensitivity analyses were performed.

RESULTS

In the base-case analysis, assuming a 2.0% probability of ACC for a 4-cm tumor, surgery was more cost-effective than surveillance (ICER $25,843/LYS). Both surgery and surveillance were incrementally more cost-effective than sign-off ($35/LYS and $8/LYS, respectively). Sensitivity analysis demonstrated that the model was sensitive to patient age, tumor size, probability of ACC, mortality of ACC, and cost of hospitalization. The results of the model were stable across different cost and complications related to adrenalectomy, regardless of operative approach.

CONCLUSION

In our model, adrenalectomy was cost-effective for neoplasms >4 cm and in patients <65 years, primarily owing to the aggressiveness of ACC. Current AACE/AAES guideline recommendations for the resection of adrenal incidentalomas ≥ 4 cm seem to be cost-effective.

Adrenal incidentalomas

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.