Differentiation of malignant from benign adrenal masses: predictive indices on computed tomography

Fluoro-2-Deoxyglucose-Positron Emission Tomography/Computed Tomography in the Diagnosis and Management of Adrenocortical Carcinoma: A 10-Year Experience from a Tertiary Care Institute

Purpose

Adrenocortical carcinoma (ACC) is a rare primary malignancy of the adrenal gland. The present study was aimed to compare the performance of fluoro-2-deoxyglucose-positron emission tomography-computed tomography (FDG-PET-CT) compared to contrast-enhanced computed tomography (CECT) in diagnosis and management of ACC.

Materials and Methods

A retrospective analysis of the PET-CT studies from January 2010 to October 2020 was performed. Patients with adrenal lesions suspicious of ACC and diagnosed cases of ACC who underwent PET-CT for staging, restaging, and surveillance were reanalyzed. The PET-CT parameters were compared with the clinical, biochemical, histopathological, and CECT parameters.

Results

The study included 96 scans performed in 77 patients (36 males, aged 40.4 ± 17.9 years). Of these, 55 scans were performed to diagnose and stage suspected ACC (30 of them diagnosed as ACC), 31 for restaging, and 10 scans for surveillance of ACC. PET/CT revealed metastases from an extra-adrenal primary in 5/55 patients. FDG-PET-CT had a sensitivity and specificity of 100% and 70% to diagnose ACC. Standardized uptake value-peak more than 5.4 had a sensitivity of 90.9% and specificity of 91.7% for differentiating ACC from non-ACC lesions, while tumor-to-liver ratio peak (TLRpeak) of 3.3 was most specific. PET-CT changed the staging in 23.3% of the patients with an accuracy of 100%. PET-CT changed the management plan in 25.8% of the patients during restaging with a sensitivity and specificity of 95.6% and 100%, respectively. For surveillance, CECT was as sensitive as PET-CT; however, PET-CT was more specific (100% vs. 97.9%).

Conclusion

FDG-PET-CT performs better than CECT in the diagnosis, staging, restaging, and surveillance of ACC.

[Diagnostic value of ct in examination of patients with adrenal cancer]

BACKGROUND

In most cases adrenal tumours are detected by accident while performing medical imaging tests for other diseases. These findings are treated as adrenal incidentaloma. Prevalence of incidentalomas detected on CT scans is up to 4%. According to different authors, 4-12% of all adrenal tumours are adrenocortical carcinomas. As for today, the most significant medical imaging technique is CT scan with bolus IV injection of contrast agent and assessment of tumour's density. The analysis of the results of CT imaging in 67 patients with ACC was carried out according to a single protocol. The main signs characteristic of this disease are described. It is very important to evaluate typical signs of ACC on CT scans for risk assessment of ACC before surgical treatment. If malignant tumour is suspected during preoperative examination, it is extremely important to choose the right surgical treatment strategy.

AIM

To evaluate the significance of CT as the main method of preoperative diagnosis in patients with malignant tumors of the adrenal cortex. Studying CT semiotics of adrenocortical cancer in a large group of patients using a single standard imaging protocol. Find the main radiological symptoms characteristic of adrenocortical cancerMATERIALS AND METHODS: Here are the results of retrospective study of CT scans performed on 67 patients with adrenocortical carcinoma who received treatment in the Department of Endocrine Surgery of Saint-Petersburg State University N.I. Pirogov Clinic of High Medical Technologies during 2012-2020. The diagnostic significance of CT in patients with ACC was assessed.

RESULTS

The most common features of ACC: tumour heterogeneity (84.3%), tumour's size 3-9 cm (75%), signs of invasion into surrounding structures (10%), pre-contrast density above +30 HU (75%), absolute contrast washout less than 60% (68.8%), relative contrast washout less than 40% (64.6%)CONCLUSION: CT scan with IV contrast was not able to show any definitive pathognomonic signs of ACC. Nevertheless, CT scan should be performed in all patients with suspected (or confirmed using other medical imaging technique) adrenal tumour according to standard protocol. Bolus injection of contrast agent should be performed in all patients with tumour's pre-contrast density above +5 HU.

Adrenocortical Carcinoma Diagnosed by Endoscopic Ultrasound-guided Fine-needle Aspiration

Adrenocortical carcinoma (ACC) is a rare malignancy with a very poor prognosis. A 77-year-old man underwent imaging studies due to poorly controlled hypertension, which revealed a mass measuring 43 mm in diameter near the left adrenal gland. There were no findings indicative of pheochromocytoma. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed for the preoperative pathological evaluation, and the findings indicated a possibility of ACC. Based on these results, curative surgery was performed. If the diagnosis of pheochromocytoma is excluded, then EUS-FNA for adrenal lesions is relatively safe. It can also be used for the preoperative diagnosis of ACC.

Tumors presenting in both pediatric and adult patients: a case-based review of pathology and imaging features for the radiologist

Various pathologic neoplasms present in both childhood and adulthood. Multiple environmental and genetic factors with different targets at different ages have been implicated in prior literature. These tumors include Multi-Locular Cystic Renal Tumors (MCRT), Adrenocortical Carcinomas, Paragangliomas, Hepatic Hemangiomas, and Medullary Renal Cell Carcinomas. The pertinent imaging, pathological, and clinical features of these select entities are discussed to assist the General and Pediatric Radiologist in accurate interpretation and treatment planning.

Association between Tumor Size and Malignancy Risk in Hormonally Inactive Adrenal Incidentalomas

Introduction

Adrenal incidentalomas (AI) are adrenal masses that are discovered during radiological examinations conducted for other reasons. In this study, we focused on the pathological and radiological properties of nonfunctional AI(NFAI) and the association with malignancy risk in our clinical series.

Methods

A total of 186 patients underwent adrenalectomy between 2010 and 2017; of these, 76 (40.8%) patients with non-functional AI were included in the current study. The radiological and pathologic characteristics of these AIs were retrospectively analyzed to determine the malignancy rate.

Results

There were 22 (28.9%) male and 54 (71.1%) female patients with nonfunctional AI included in this study. The median age was 55 (range: 24-85) years. Of the patients included, 37 (48.6%) had AI on the left and 39 (51.3%) had AI on the right adrenal gland. Sixty-one (80.2%) cases were treated laparoscopically, four (5.3%) required conversion to open surgery due to intraoperative difficulties such as bleeding and adhesions, and 11 (14.4%) were managed with open adrenalectomy. The rate of malignancy in the tumors with diameters of <4 cm, 4-6 cm, and >6 cm was found to be 0%, 2.9%, and 13.6%, respectively.

Conclusions

Determining the ideal cutoff value for surgical indication in an NFAI is challenging. Besides the malignancy risk, the rate of silent pheochromacytomas must be taken into account in the surgical decision.

Interobserver agreement in distinguishing large adrenal adenomas and adrenocortical carcinomas on computed tomography

PURPOSE

Large adrenal masses pose a diagnostic dilemma. The purpose of this study was twofold: first, to assess the degree of interobserver agreement in evaluating the morphology of pathologically proven adrenal adenomas and adrenocortical carcinomas larger than 4 cm in diameter; and second, to identify morphologic characteristics that correlated with the pathologic diagnosis.

MATERIALS AND METHODS

For this blinded, retrospective study, we collected cases of 25 adrenal adenomas and 33 adrenocortical carcinomas measuring larger than 4 cm. Two radiologists evaluated morphologic characteristics of the lesions on CT. Interobserver agreement was evaluated using kappa statistics, and the correlation of imaging characteristics with the diagnosis was evaluated using a logistic regression model.

RESULTS

We found the highest interobserver agreement in the assessment of precontrast attenuation (Κ = 0.81) as well as substantial agreement in determining the shape and the presence of calcifications (Κ = 0.69 and 0.74, respectively). Readers agreed less often regarding the presence of fat (Κ = 0.48), as well as regarding the presence of necrosis, heterogeneity, and the overall impression (Κ = 0.15, 0.24, and 0.26, respectively). CT characteristics correlated with benignity included round shape (p = 0.02), an overall radiologic impression of a benign lesion (p < 0.0001), the presence of fat (p = 0.01), and a precontrast attenuation of less than 10 Hounsfield units (p < 0.0001). The latter two of these characteristics were highly specific for benign pathology (93% and 100%, respectively).

CONCLUSION

Our study suggests that CT has the ability to consistently identify characteristics significantly correlated with benign vs. malignant adrenal tumors.

Clinical Case Seminar: Postmenopausal androgen excess-challenges in diagnostic work-up and management of ovarian thecosis

Postmenopausal hyperandrogenism can be tumour- or non-tumour-related, with pathology residing either in the ovary or adrenal gland(s). The tempo of investigation is determined by the clinical severity of hyperandrogenism (presence/absence of actual virilisation) and degree of serum testosterone elevation. When clinical or biochemical hyperandrogenism is severe, rapidly developing, or associated with hypercortisolism, screening for adrenocortical or ovarian carcinoma with cross-sectional imaging should be prioritised over detailed biochemical evaluation. Adrenal hyperandrogenism is readily characterised, both biochemically and radiologically. By contrast, even a combination of high-resolution imaging with laboratory evaluation, including dynamic endocrine testing, often cannot distinguish between ovarian hyperthecosis (OH) and virilising ovarian tumour (VOT); a definitive diagnosis usually emerging only after histological examination of excised ovaries. VOTs are typically below the resolution-limit of current imaging modalities and exhibit suppression of gonadotropin-dependent androgen secretion with GnRH-analogue therapy. Thus, for well-characterised ovarian hyperandrogenism, laparoscopic bilateral salpingo-oophorectomy may serve both as a diagnostic and therapeutic procedure. Nevertheless, women unable or unwilling to undergo ovarian surgery can be reassured that malignant VOTs are exceedingly rare and that long-term medical therapy with oral antiandrogens or GnRH-analogues is safe and well-tolerated. OH is strongly associated with insulin-resistance, with hyperinsulinaemia acting synergistically with raised gonadotropin levels to stimulate thecal cell hyperplasia and androgen secretion by the postmenopausal ovary, which lacks granulosa cell aromatase activity and thus cannot convert testosterone to 17 beta estradiol. Thus, features of metabolic syndrome may indicate OH, and significant reductions in androgens can thereby potentially be achieved with lifestyle measures and/or insulin-sensitising drugs.

Adrenocortical neoplasms in adulthood and childhood: distinct presentation. Review of the clinical, pathological and imaging characteristics

Adrenocortical tumors (ACT) in adulthood and childhood vary in clinical, histopathological, molecular, prognostic, and imaging aspects. ACT are relatively common in adults, as adenomas are often found incidentally on imaging. ACT are rare in children, though they have a significantly higher prevalence in the south and southeast regions of Brazil. In clinical manifestation, adults with ACT present more frequently with glucocorticoid overproduction (Cushing syndrome), mineralocorticoid syndromes (Conn syndrome), or the excess of androgens in women. Subclinical tumors are frequently diagnosed late, associated with compression symptoms of abdominal mass. In children, the usual presentation is the virilizing syndrome or virilizing association and hypercortisolism. Histopathological grading and ACT classification in malignant and benign lesions are different for adults and children. In adults, the described criteria are the Hough, Weiss, modified Weiss, and Van Slooten. These scores are not valid for children; there are other criteria, such as proposed by Wieneke and colleagues. In molecular terms, there is also a difference related to genetic alterations found in these two populations. This review discusses the imaging findings of ACT, aiming to characterize the present differences between ACT found in adults and children. We listed several differences between magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography-computed (PET-CT) and also performed a literature review, which focuses on studied age groups of published articles in the last 10 years regarding cortical neoplasm and imaging techniques. Published studies on ACT imaging in children are rare. It is important to stress that the majority of publications related to the differentiation of malignant and benign tumors are based almost exclusively on studies in adults. A minority of articles, however, studied adults and children together, which may not be appropriate.

CT and Angiography in Adrenocortical Carcinoma

CT and angiography were performed in 15 patients with adrenocortical carcinoma. The tumors had a mean diameter of 11 cm (range 4–20 cm). At CT, the 8 largest tumors were ill-defined, and in these, the organ of tumor origin could not be established. Angiographically the correct organ of tumor origin was established in all but one patient. It is concluded that CT is excellent in showing the extent of an adrenal tumor, but is often unable to predict the organ of origin in large tumors. Angiography is still of great value in the preoperative work-up in patients with large adrenocortical carcinomas for correct identification of tumor origin and for vascular mapping.

Features of Irradiated Urinary Bladder Tumors and Their Correlation with Malignancy Observed on Computed Tomography

CT features of 42 masses in the bladder wall were characterized and subjected to analysis to find indicators of malignancy. A CT technique with thin slices and intravenous contrast medium was used. Multiple regression and multivariate analysis showed good ability of contrast-enhanced CT to discriminate between benign and malignant masses in the bladder wall. Protrusion of a mass into the perivesical fat had some importance in discriminating between malignant tumors with and without perivesical growth although the detection of perivesical growth was less certain.

Computed Tomography in Primary and Secondary Adrenal Tumours

The purpose of the study was to find out how reliably benign and malignant adrenal tumours can be differentiated on the basis of CT characteristics. The material included 86 adrenal tumours with the following confirmed diagnoses: 48 primary adrenal tumours (8 carcinomas, 1 neuroblastoma, 4 pheochromocytomas, 31 adenomas, 3 cysts, 1 haemangioma) and 38 metastases. The size, density, homogeneity, enhancement and growth of the tumours were evaluated. No specific CT findings could separate benign from malignant tumours. Coexistence of cancer and bilateral non-homogeneous adrenal masses is probably sufficient for the diagnosis of adrenal metastases. In cases of coincidental small (<3 cm), homogeneous and relatively hypodense masses with no signs of hormonal activity, a follow-up examination of the lesion within three months is recommended. Other masses may indicate further diagnostic procedures.

Computed Tomography of Adrenal Metastases in Hepatocellular Carcinoma

Four patients with adrenal metastases from hepatocellular carcinoma (HCC) diagnosed with computed tomography are described. In three, the metastases showed a central area of low density due to tumor necrosis, irregular contrast enhancement, and a well-defined margin. They measured 8 cm or more in diameter. In one, the adrenal metastasis was at first a relatively small homogeneously solid mass, but later, when it grew larger, a central low density developed. Since the adrenal gland is the second most common site of metastasis from HCC at autopsy, a combination of an adrenal tumor and a liver tumor should suggest this possibility.

Likelihood ratio of computed tomography characteristics for diagnosis of malignancy in adrenal incidentaloma: systematic review and meta-analysis

Purpose

To propose an evidence based diagnostic algorithm using mass characteristics to determine malignancy in patients with adrenal incidentaloma by CTscan.

Methods

A systematic review in Medline, Scopus, relevant reference books and desk searching was performed up to January 2016 with relevant reference checking. The summery estimates of sensitivity, specificity, positive and negative likelihood ratio of different characteristics were calculated in two groups of the articles investigating the cases without previous malignancy and the articles investigating the oncologic cases.

Results

Thirty six articles were included in this study. In the first group with no history of malignancy a positive and negative LR of 3.1 and 0.13 in 4 cm threshold and positive and negative LR of 2.85 and 0 in 10HU density were found. In the second group with history of malignancy positive and negative LR of 2.3 and 0.27 in 3 cm threshold and positive and negative LR of 3.6 and 0.08 in 20HU density were resulted.

Conclusion

The results retrieved in this study considering the limitations show that adrenal incidentaloma with a size less than 4 cm or a mass larger than 4 cm with density less than 10HU in the first group can be managed with imaging follow up. For masses larger than 4 cm with density more than 10HU another diagnostic procedure should be performed. In the second group an adrenal mass larger than 3 cm or less than 3 cm with density more than 20HU should go under operation. But masses smaller than 3 cm with less than 20HU density can be followed by imaging.

Adrenal Imaging and Intervention

The adrenal glands are a common site for primary benign and malignant tumors and metastatic disease. Computed tomography (CT), MR imaging, and fluorine-18 fluorodeoxyglucose PET combined with CT are the most common imaging modalities used to assess the adrenal glands. There are established morphologic criteria for both CT and MR imaging that can be used to assess whether an adrenal mass is benign or malignant, and whether follow-up, biopsy, or resection should be performed. In the setting of a known primary malignancy, CT, MR imaging, and PET can help differentiate most benign masses from metastasis.

From the radiologic pathology archives: Adrenal tumors and tumor-like conditions in the adult: radiologic-pathologic correlation

Advanced imaging often reveals adrenal tumors and tumor-like conditions in both symptomatic and asymptomatic patients. When adrenal disease is clinically suspected, cross-sectional imaging can be helpful in evaluating the etiology of the patient's symptoms. When adrenal disease is incidentally identified, what the clinician and patient really want to know is whether the findings are benign or malignant, as this ultimately will affect their next step in management. Using radiologic-pathologic correlation, we broadly classify common, uncommon, and rare tumors and tumor-like conditions that can occur in the adrenal as benign or malignant. This classification follows predominant trends in observed biologic behavior while acknowledging those tumors that may behave in the minority in an unpredictable manner. We review the clinical background and presentation of functional adrenal tumors including Conn syndrome, Cushing syndrome, and catecholamine-secreting tumors, as well as their relationship with adrenal anatomy. We discuss a variety of benign tumors, including adrenal cortical adenoma (including oncocytoma) and pheochromocytoma, as well as uncommonly and rarely encountered tumors such as myelolipoma, hemangioma, lymphangioma, schwannoma, ganglioneuroma, and adenomatoid tumor. A variety of tumefactive but nonneoplastic lesions are addressed, including adrenal cortical hyperplasia, adrenal hemorrhage, adrenal cysts, and infections. Malignant tumors discussed include adrenal cortical carcinoma, the rare malignant pheochromocytoma, lymphoma, metastases, and sarcomas. For each tumor and tumor-like lesion, the clinical presentation, epidemiology, key imaging findings, diagnostic differential considerations, and management options are briefly addressed. Finally, an approach to the workup of suspected or incidentally discovered tumors is presented based on a selected literature survey and our clinical experience. Radiologists play an important role in identification and diagnosis of adrenal tumors and tumor-like conditions in both symptomatic and asymptomatic patients.

Radiographic evaluation of nonfunctioning adrenal neoplasms

Incidental adrenal neoplasms are usually nonfunctioning benign adenomas. Once hormonal production has been assessed, the nonsecreting lesions must be evaluated for the possibility of malignancy. This evaluation relies primarily on the radiographic characteristics. This article focuses on the current state of radiologic technology available to accurately assess nonfunctioning adrenal incidentalomas. As this technology advances, a lesion's malignant potential can more accurately be determined, thereby allowing physicians to make more informed treatment recommendations.

Surgical management of adrenocortical tumours

The surgical treatment of adrenal tumours has evolved over the past century, as has our understanding of which hormones are secreted by the adrenal glands and what these hormones do. This article reviews the preoperative evaluation of patients with adrenal tumours that could be benign or malignant, including metastases. The biochemical evaluation of excess levels of hormones is discussed, as are imaging characteristics that differentiate benign tumours from malignant tumours. The options for surgical management are outlined, including the advantages and disadvantages of various open and laparoscopic approaches. The surgical management of adrenocortical carcinoma is specifically reviewed, including controversies in operative approaches as well as surgical management of invasive or recurrent disease.

Adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy, often with an unfavorable prognosis. Here we summarize the knowledge about diagnosis, epidemiology, pathophysiology, and therapy of ACC. Over recent years, multidisciplinary clinics have formed and the first international treatment trials have been conducted. This review focuses on evidence gained from recent basic science and clinical research and provides perspectives from the experience of a large multidisciplinary clinic dedicated to the care of patients with ACC.

Adrenal imaging: a comprehensive review

The discovery of an incidental adrenal mass (adrenal incidentaloma) continues to rise with the increasing use of cross-sectional imaging. Although most adrenal lesions are benign and asymptomatic, radiologists should guide evaluation of these lesions, whether benign or malignant. This article reviews the various imaging techniques used to evaluate adrenal masses and their relative strengths and weaknesses. It focuses on the most prevalent adrenal pathologies and their typical imaging characteristics, and concludes with a brief discussion of developing techniques, including diffusion-weighted imaging and dual-energy CT.

Adrenocortical carcinoma: the range of appearances on CT and MRI

OBJECTIVE

Adrenocortical carcinoma (ACC) is a rare, aggressive tumor arising from the adrenal cortex that typically presents late with a large mass. The increased use of cross-sectional imaging for unrelated reasons has led to a greater number of ACCs being detected incidentally at an earlier stage. Recognition of the typical clinical, biochemical, and imaging findings is imperative for rapid diagnosis, prompt intervention, and early use of the appropriate therapy.

CONCLUSION

Cross-sectional imaging with CT and MRI is essential for determining the extent of local and distant tumor spread. Complete surgical resection is currently the only potentially curative treatment of ACC, and the information attained from CT and MRI is important to guide surgery and further patient management.

Androgen- and estrogen-secreting adrenal cancers

Androgen-secreting adrenal cancers are extremely rare malignancies, accounting for only a tiny proportion of the total number of women presenting with signs of androgen excess. Estrogen-secreting adrenal cancers are rarer still. Understanding how these tumors work benefits from an appreciation of adrenal steroid biosynthesis, as it is said that secretion in cancers is an anarchic version of normal adrenal function. Selection of patients in whom we should have a high suspicion of a malignancy is vital, so that biochemical investigation and imaging is deployed appropriately. When an adrenal tumor is found to secrete androgens or estrogens to excess, it can be difficult to confirm that it is a cancer, as there is significant overlap in the secretory patterns and imaging appearances of benign and malignant disease. The most reliable indicator of malignancy in these tumors remains the presence of metastases. Treatment is essentially surgical, although the role of mitotane is one undergoing evaluation.

Laparoscopic adrenalectomy: balancing the operative indications with the technical advances

Laparoscopic adrenalectomy contributed significantly to reduction of morbidity and improvement of postoperative patient recovery time. The adoption of this technique had substantial impact on the management of adrenal incidentalomas. Although laparoscopic adrenalectomy should be in general avoided for known primary adrenal cancers, it is appropriate for metastasectomy of isolated adrenal metastatic disease.

Feminizing adrenocortical adenoma in a 5 year-old girl

Adrenocortical adenoma is a rare etiology of isosexual precocious puberty in girls. We report the case of a 5 year-old girl with isosexual precocious puberty. Abdominal ultrasound and magnetic resonance imaging revealed a well-defined mass of 32 x 28 mm situated in the left suprarenal region, but no signs of calcification or metastasis. Estradiol and testosterone levels were elevated, cortisol plasma level was normal, and bolus intravenous injection of GnRH showed unresponsiveness of LH and FSH. Pathological examination after complete surgical resection showed an adrenocortical adenoma. Five years later, there had been no recurrence and abdominal ultrasound examination was normal. The diagnosis of feminizing adrenocortical adenoma was confirmed.

Adrenocortical Positron Emission Tomography/PET-CT Imaging

The frequency for detecting asymptomatic adrenal masses is increasing because of the common use of computed tomography and MR imaging in the practice of medicine. CT and MR imaging have played an important role in defining certain physiologic and pathologic ingredients of the adrenal glands; however, it is sometimes difficult to characterize adrenal masses with CT or MR imaging alone. In such cases, further characterization of the adrenal masses can be achieved using functional imaging modalities. Positron emission tomography (PET) using 18-F-fluorodeoxyglucose (FDG) has performed well in the evaluation and management of various malignant conditions. FDG-PET has also shown excellent results in the evaluation of primary and metastatic malignant adrenal disease with poor differentiation. This article discusses in detail various PET radiopharmaceutics which can be used for adrenocortical imaging.

Papillary Endothelial Hyperplasia of the Adrenal Gland: Report of a Case and Review of the Literature

Papillary endothelial hyperplasia (PEH) is a benign vascular proliferative process most frequently seen in the skin and integument, but may involve any of the visceral organs. It is a rare entity, with less than 30 cases of visceral PEH described in the literature. Adrenal papillary endothelial hyperplasia is an exceedingly rare process and is the basis of this review. A 66-year-old female was referred for evaluation of an asymptomatic 6 cm right adrenal mass. Computed tomography indicated that the lesion was solid and hypervascular. After appropriate workup, the patient underwent laparoscopic adrenalectomy. The pathologic analysis was consistent with adrenal PEH. The patient recovered without incident and is doing well at 1 year follow-up. A review of the world's literature on papillary endothelial hyperplasia (PEH), and in particular adrenal PEH, yields five previous reports of this entity, and no comprehensive review. A compilation of the now six patients with adrenal PEH reveals several common features: five of six patients were female and mean age was 64 years. The disease radiologically mimics adrenal cortical carcinoma mandating a surgical oncological technique. Pathologic differentiation from angiosarcoma can be a difficult task requiring evaluation by an experienced pathologist.

The investigation and management of severe hyperandrogenism pre- and postmenopause: non-tumor disease is strongly associated with metabolic syndrome and typically responds to insulin-sensitization with metformin

BACKGROUND

An androgen-secreting tumor needs to be excluded in any woman with severe hyperandrogenism. We sought to characterize patients with biochemical hyperandrogenism in respect of tumor versus non-tumor etiologies, explore possible links between non-tumor hyperandrogenism and metabolic syndrome, and ascertain whether metformin therapy can elicit diagnostic reductions in serum testosterone (T).

PATIENTS AND METHODS

Seven-year retrospective study of all women referred to a university hospital endocrinology service with baseline T >4.0 nmol/l. Dataset comprised age, menopausal status, body mass index (BMI), presence/absence of hypertension, diabetes, acanthosis or dyslipidemia, along with changes in BMI and serum T following intervention with metformin, oophorectomy or dexamethasone. Non-tumor hyperandrogenism was defined by normalization of serum T or >40% reduction from baseline.

RESULTS

Four out of 18 cases had adrenal carcinoma that was clinically obvious at initial presentation (one virilized, three Cushingoid). The remaining 14 were characterized by metabolic syndrome (BMI: 39.9 +/- 8.1 kg/m(2)), serum T of 6.14 +/- 1.6 nmol/l, and nadir serum T following intervention of 2.2 +/- 1.04 nmol/l. Diagnostic reductions in serum T occurred in 11/12 patients treated with metformin.

CONCLUSIONS

Non-tumor hyperandrogenism with markedly elevated serum T and associated metabolic syndrome is a defined clinical entity in postmenopause as well as in premenopausal women with polycystic ovary syndrome. This has hitherto been only sparsely documented in the published literature. A fall in serum T level in response to insulin-sensitizing therapy with metformin and lifestyle change may be a reassuring indicator that such women are highly unlikely to harbor an androgen-secreting tumor.

Differentiation of adrenal adenoma and nonadenoma in unenhanced CT: new optimal threshold value and the usefulness of size criteria for differentiation

OBJECTIVE

To determine the optimal threshold for the attenuation values in unenhanced computed tomography (CT) and assess the value of the size criteria for differentiating between an adrenal adenoma and a nonadenoma.

MATERIALS AND METHODS

The unenhanced CT images of 45 patients at our institution, who underwent a surgical resection of an adrenal masses between January 2001 and July 2005, were retrospectively reviewed. Forty-five adrenal masses included 25 cortical adenomas, 12 pheochromocytomas, three lymphomas, and five metastases confirmed by pathology were examined. The CT images were obtained at a slice thickness of 2 mm to 3 mm. The mAs were varied from 100 to 160 and 200 to 280, while the 120 KVp was maintained in all cases. The mean attenuation values of an adrenal adenoma and nonadenoma were compared using an unpaired t test. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy at thresholds of 10 HU, 20 HU, and 25 HU were compared. The diagnostic accuracy according to the size criteria from 2 cm to 6 cm was also compared.

RESULTS

The twenty-five adenomas showed significantly lower (p < 0.05) attenuation values (mean+/-SD; 16.3+/-14.9) than the nonadenomas (38.1+/-6.8). Nineteen (90%) of the 20 nonadenomas had attenuation values ranging from 30 to 50 HU. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosing adenomas were 36%, 100%, 100%, 56%, and 64%, respectively, at a threshold of 10 HU; 60%, 100%, 100%, 67%, and 78%, respectively, at a threshold of 20 HU; and 72%, 95%, 95%, 73%, and 82%, respectively, at a threshold of 25 HU. The adenomas had a significantly (p < 0.05) smaller diameter (2.44+/-1.24 cm) than the nonadenomas (5.09+/-2.37 cm). The size criteria using a diameter of 4-6 cm showed a sensitivity > 90% but a specificity < 70%. Size criteria of 2 or 3 cm had a high specificity of 100% and 80% but a low sensitivity of 20% and 60%.

CONCLUSION

The threshold attenuation values of 20 or 25 HU in the unenhanced CT appear optimal for discriminating an adrenal adenoma from a nonadenoma. The size criteria are of little value in differentiating adrenal masses because of their low specificity or low sensitivity.

Diagnosis and management of adrenal cortical carcinoma

Adrenal cortical carcinoma is a relatively uncommon malignancy that represents a significant clinical challenge for the development of optimal treatment strategies. Historically, successful treatment has relied upon rapid identification of the lesion, accurate staging with diagnostic imaging, and complete surgical extirpation. Although the framework of a successful treatment paradigm still relies on these steps, advances in diagnostic imaging have led to increased accuracy in diagnosis, and advances in laparoscopic surgical technique have served to reduce morbidity for patients facing treatment. This review focuses on a discussion of advances in modalities for the diagnosis and treatment of adrenal cortical carcinoma amenable to curative therapy. Patients that present with metastatic or locally advanced disease generally are treated with mitotane-based chemotherapy with or without the addition of cytotoxic drugs. Contemporary results of this treatment approach are presented in this review as well as a discussion of further directions for the treatment of patients with advanced disease.

Analysis of adrenal masses by 18F-FDG positron emission tomography scanning

This study aimed to analyse the characteristics of adrenal masses visible in the computerised tomography (CT) scans which have been also evaluated by 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (18F-FDG PET), and to characterise the features of 18F-FDG PET scans associated with various adrenal endocrine tumours, especially benign functional tumours. 18F-FDG PET scans of 105 patients with adrenal masses on the CT scan were analysed. Positive uptakes in the 18F-FDG PET scans were seen in 60 malignant tumours (54 metastasic lesions, six primary adrenal cancers) and seven benign tumours. The positive predictive value of 18F-FDG PET imaging to characterise an adrenal mass as a malignant tumour was 90%; the corresponding negative predictive value to rule out malignancy was also 90%. Benign adrenal tumours were smaller than that of malignant lesions (p<0.05). The mean standardised uptake value max (SUVmax) of the metastatic lesions [8.4+/-6.5 (microCi/g)/microCi/kg] was significantly higher than that of the benign adrenal tumours [2.4+/-1.2 (microCi/g)/microCi/kg, p<0.001]. Examination of only the primary adrenal lesions revealed that all adrenocortical carcinomas, two of three cases of pheochromocytomas, three of five neuroblastomas and two of four cases of primary aldosteronism showed positive 18F-FDG uptake. In conclusion, for patients presenting adrenal masses with a high probability of malignancy, 18F-FDG PET can be used to differentiate malignant from benign adrenal lesions. However, the 18F-FDG PET uptake did not show an always consistent pattern for endocrine tumours, which was probably due to the variability inherent in 18F-FDG uptake. This study suggests that 18F-FDG PET scanning can offer supporting data to localise and characterise adrenal tumours.

Outcomes of adrenal cortical carcinoma in the United States

BACKGROUND

Improvements in the sensitivity of radiographic imaging have lead to an increase in the number of adrenal masses diagnosed. The purpose of this study is to determine if technologic advancements have resulted in the diagnosis of earlier-staged adrenal cortical cancer (ACC) and to determine if the survival of patients with ACC has improved over the past 15 years.

METHODS

Patients with ACC were identified in the Surveillance, Epidemiology, and End Results database between 1988 and 2002. Changes in demographics, stage, size, and treatment were analyzed by standard statistical testing.

RESULTS

We identified 602 patients with a mean age of 53 years and an average tumor size of 11.8 cm. Two hundred thirty-eight (39.5%) patients presented with localized disease (stages I and II), and 311 (52%) patients presented with advanced disease (stages III and IV). The comparison of smaller lesions and number of patients were 5 to 6 cm in 24 (4%) patients, 4 to 5 cm in 27 (4.5%) patients, and <4 cm in 19 (3.1%) patients. Patients with masses less than 5 cm were statistically more likely to have localized disease (P <. 001). Age (P = .10), tumor size (P = .85), tumor stage (P = .45), and 5-year survival (P = .5) did not change over the 15-year study.

CONCLUSIONS

Over the 15-year study, patients with ACC were not diagnosed at an earlier stage or with tumors smaller, and survival did not improve.

Adrenal metastases of malignant melanoma: Characteristic computed tomography appearances

Malignant melanoma is an extremely aggressive form of cancer. Adrenal metastases are found in 50% of cases of malignant melanoma, and are most often clinically and biochemically silent. Clinical presentation varies, and the diagnosis of adrenal metastases is often made incidentally, and frequently years after treatment of the primary lesion. An adrenal mass lesion seen on a CT scan, greater than 5 cm in diameter, with central or irregular areas of necrosis/haemorrhage (and no lipomatous component) is characteristic of a metastasis from malignant melanoma, in the setting of normal gland function. If these features are bilateral, they are pathognomonic. Oval, low-attenuation (on CT) adrenal masses less than 3 cm in diameter should not be considered benign in a patient with any prior history of melanoma. Careful imaging review of the adrenal glands should be undertaken in all patients with malignant melanoma. Early diagnosis of these distant metastases has important prognostic and therapeutic implications. The four cases presented illustrate the spectrum of presentations and clinical course of adrenal metastases from malignant melanoma. The accompanying CT images show the characteristic appearances of adrenal metastases.

Clinical utility of noncontrast computed tomography attenuation value (hounsfield units) to differentiate adrenal adenomas/hyperplasias from nonadenomas: Cleveland Clinic experience

Radiological characterization of an adrenal tumor as adenoma may decrease the need for follow-up imaging studies, biopsies, and unnecessary adrenalectomies. We retrospectively reviewed 299 adrenalectomies in 290 patients at Cleveland Clinic Foundation over a recent 5-yr period to assess the value of noncontrast Hounsfield units (HU) in characterizing whether an adrenal mass is adenoma or nonadenoma. The mean (+/- SD) HU value for the adrenocortical adenoma/hyperplasia group was 16.2 +/- 13.6 and significantly lower (P < 0.0001) than primary adrenocortical cancers (36.9 +/- 4.1), metastases (39.2 +/- 15.2), and pheochromocytomas (38.6 +/- 8.2). The sensitivity and specificity for 10- and 20-HU cutoff values to differentiate adenomas/hyperplasias from nonadenomas were 40.5 and 100% and 58.2 and 96.9%, respectively. The size of the adrenal tumor had less value with only 40.7 and 81.3% sensitivity and 94.7 and 61.4% specificity for 2- and 4-cm cutoff values. A combination of less than or equal to 4-cm adrenal mass size and noncontrast computed tomography HU less than or equal to 20 had 42.1% sensitivity and 100% specificity. Our study, the largest with surgical histopathology as the gold standard for diagnosis, supports a noncontrast computed tomography attenuation value of 10 HU as a safe cutoff value to differentiate adrenal adenomas/hyperplasias from nonadenomas.

Does tumor heterogeneity limit the use of the Weiss criteria in the evaluation of adrenocortical tumors?

Adrenal incidentalomas are detected more frequently with high-resolution imaging modalities. It is difficult to distinguish between benign and malignant lesions despite the so-called histologic Weiss criteria, imaging features, and molecular studies. We here present a 52 yr-old man who was found to have an adrenal incidentaloma during an annual check-up at his urologist. An 8 cm large adrenal lesion was detected on ultrasound, computed tomography, and magnetic resonance imaging with imaging features suggestive of malignancy. The lesion was hormonally inactive. A left-sided adrenalectomy was performed and histologic grading revealed a Weiss score of 2, suggesting a benign tumor. However, on further follow-up, the patient developed a local recurrence and pulmonary metastases diagnosed 6 yr after initial presentation. After repeat surgery in the left adrenal bed adrenocortical tumor tissue had a Weiss score of 8, clearly suggesting histologic malignancy. The patient received adjuvant mitotane therapy. Under this therapy, he developed a right-sided adrenal mass (contralateral from the primary tumor) of 2 cm size which disappeared during the following 9 months, whereas the pulmonary metastases remained unchanged, suggesting tumor clones with a variable response to treatment or spontaneous apoptosis. This case suggests that adrenal incidentalomas larger than 6 cm with imaging features such as intratumoral necrosis suggestive of malignancy, should be managed as potential cancers independent of the so-called Weiss criteria. In such patients, close follow-up examinations including high-resolution imaging (preferably 3 monthly) are needed and should be carried out by a physician familiar/specialized in endocrine oncology.

Adrenal tumors: how to establish malignancy ?

Discerning malignancy in adrenal tumors largely influences disease management and is, therefore, of utmost importance to both patient and physician. Clinical presentation (e.g. virilization) and baseline hormonal evaluation (e.g. high serum DHEAS) are occasionally of great value but usually provide only limited help in predicting malignancy. The probability of malignancy is clearly related to tumor size, as almost all lesions <3 cm are benign whereas a diameter of >6 cm indicates a high risk of malignancy. Computed tomography (CT) and magnetic resonance imaging (MRI) both contribute significantly to the characterization of adrenal masses. If the attenuation of a homogeneous mass with smooth border is 10 Hounsfield units or less in unenhanced CT the diagnosis of a lipid rich adenoma is established. Similarly, enhancement washout of more than 50% in CT at 10-15 min suggests a benign lesion. In MRI both rapid contrast enhancement after gadolinium followed by rapid washout and signal intensity loss using opposed-phase image in chemical shift analysis also indicate the presence of an adenoma. In contrast, adrenal carcinomas--but also pheochromocytomas--typically present as inhomogeneous lesion with intermediate-to-high intensity on T2 images in MRI. Margins and enhancement after contrast media in CT are irregular in adrenal carcinoma. Other imaging techniques either offer little additional information (NP-59 scintigraphy) or have not yet been fully established (positron emission tomography). Fine needle aspiration/cut biopsy is at present restricted to patients with a known extra-adrenal malignancy and suspected adrenal metastasis as the only evidence of disseminated disease. Adrenal tumors classified as benign undergo follow-up imaging to assess tumor growth. If an increase in diameter of >1 cm is seen, surgical removal is recommended. Even after tumor removal the diagnosis of dignity may remain difficult. Diagnostic scores together with new immunohistological markers are the methods of choice to assess malignancy. In conclusion, an interdisciplinary approach with a structured use of available diagnostic tools is needed to classify adrenal tumors correctly.

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.

Adrenal incidentalomas

The term adrenal incidentaloma refers to an adrenal mass occasionally and unexpectedly discovered by an abdominal imaging procedure performed for reasons a priori unrelated to adrenal dysfunction. The prevalence of adrenal incidentalomas as discovered by computed tomographic scan examination is estimated to be between 1% and 4%. The vast majority of these lesions are of adrenocortical origin, most often adenomas. Identification of steroid or catecholamine-secreting tumors is important but usually solved with appropriate endocrinologic investigations. A difficult problem, however, is to distinguish between benign and malignant primary or secondary tumors. Size less than 4 cm and an unenhanced computed tomographic attenuation under 10 Hounsfield Units (HU) are findings in favor of a benign adrenocortical adenoma, as is a positive NP 59 scintigraphic examination. The pathogenesis of adrenal tumors is not well understood. However, alterations of the cyclic AMP signalling pathway have recently been observed in benign adrenocortical lesions and molecular defects associated with insulin-like growth factor-II overexpression in malignant adrenocortical tumors.

Adrenal cortical carcinoma

Adrenal cortical carcinoma is a rare endocrine tumor for which complete surgical resection is the only potentially curative treatment. Accurate preoperative evaluation (biochemical and radiographic) of the patient who presents with an adrenal mass maximizes the opportunity for the patient to undergo a complete, margin-negative resection of the primary tumor, which is the most powerful prognostic variable for long-term survival. The response to chemotherapy or mitotane is modest in patients with advanced disease. Hopefully, an improved understanding of the molecular pathogenesis of this challenging tumor will lead to the development of more effective therapies in the future.

Adrenal incidentaloma

Because of the frequent use of computed tomography and other abdominal imaging modalities, clinicians more frequently see the incidentally discovered, clinically silent adrenal mass. Most adrenal incidentalomas should be evaluated for hormonal activity and assessed for their risk of malignancy. Adrenalectomy is indicated for hyperfunctioning tumors and for any potential primary malignant adrenal lesion. Nonfunctioning cortical adenomas < 4 to 5 cm in size should be followed clinically and radiographically. Laparoscopic adrenalectomy has been used increasingly as the preferred approach in patients who require surgical resection whereas open adrenalectomy is reserved for patients with large, malignant tumors. The indications for adrenalectomy in patients with nonfunctioning adrenal tumors should not be liberalized because of the laparoscopic approach.

Management of incidentally discovered adrenal masses and risk of malignancy

BACKGROUND

Incidentally discovered adrenal masses of more than 1 cm in size are relatively frequent, but the correct management of such lesions is not well established.

METHODS

Between 1980 and 1999, 158 patients (73 men [46.2%] and 85 women [53.8%]; median age, 58 years) with adrenal incidentalomas of more than 2 cm in size were observed. Sixty-eight patients (43.0%) underwent adrenalectomy. The main reasons for surgery were (1) suspicious computed tomography (CT) scan or magnetic resonance imaging (MRI) appearance or no uptake at the 75-Se-norcholesterol scintigraphy (NCS; n = 22 patients), (2) an increase in the size of the mass of more than l cm (n = 15 patients), (3) subclinical endocrine hyperfunction (n = 14 patients), and (4) mass size of more than 5 cm (n = 22 patients), with imaging-guided fine-needle aspiration biopsy with spinal-type narrow-gauge needle (FNAB) that suggested malignancy (n = 5 patients).

RESULTS

Pathologic examination showed 39 adrenocortical adenomas (57.4%), 20 adrenal malignancies (29.4%; carcinomas, 15; unsuspected metastases, 3; nonfunctioning malignant pheochromocytomas, 2), and 9 various benign lesions (13.2%). All masses that increased in size were benign. Seven malignant tumors (46.7%) were 3 to 4 cm in size, and 14 benign lesions (29.1%) were 5 to 6 cm in size. Sensitivity and specificity in the detection of malignancy were 100% and 100% for NCS (n = 34 patients) and FNAB (n = 19 patients), 75.0% and 93.7% for CT scan (n = 68 patients), and 87.5% and 100% for MRI (n = 26 patients), respectively.

CONCLUSIONS

To differentiate benign and malignant incidentalomas, NCS and FNAB are more sensitive than CT scan and MRI; size criteria are of little value.

Diagnosis and treatment of adrenal incidentaloma. A cost-effectiveness analysis

Methods of meta-analysis, decision analysis, and cost-effectiveness analysis were applied to the adrenal incidentaloma dilemma. It was shown that the life expectancy of patients with adrenal incidentalomas is decreased by a mean of about 1 year if left undiagnosed and untreated--more in cases of larger incidentalomas. Overall, selective analysis of adrenomedullary hormonal function (by urinary metanephrines) is the most cost-effective strategy. Other strategies, such as more extensive hormonal testing, imaging, and fine needle aspiration cytology may provide better cost-effectiveness in subgroups of patients, identified by signs, symptoms, and incidentaloma morphology. Full adrenal hormonal analysis is indicated in patients with larger (> or = 6 cm) incidentalomas and if the combination of hypertension and hypokalemia suggests Conn's disease. Small or medium-sized adrenal incidentalomas may be ignored if MR imaging or other tests suggest benign pheochromocytoma disorder, or patients are elderly, or both.