Clinical and molecular aspects of adrenocortical tumourigenesis

Management of adrenocortical carcinoma in Western Australia: a perspective over 14 years

BACKGROUND

Adrenocortical carcinoma is a rare but aggressive form of endocrine neoplasm that confers a poor prognosis. To date, the only Australian data published is from New South Wales. This paper describes our experience in Western Australia with a focus on surgical approach and outcomes.

METHODS

A retrospective study of patients treated for adrenocortical carcinoma in Western Australia over 14 years was performed.

RESULTS

Over the 14-year period, a total of 33 patients underwent surgery for adrenocortical carcinoma. Resection outcomes were superior in an open en bloc approach with an 85% R0 margin (P = 0.007). Local recurrence rates were lowest in an open en bloc approach (11%) compared to laparoscopic (75%). Multivariate analysis showed that an en bloc resection is highly correlated with an R0 resection (P < 0.05) and significantly associated with lower (odds ratio = 0.06) local recurrence (P = 0.009). Higher volume surgeons (>5 cases) had lower operative times and blood loss. Compliance with mitotane was significantly improved with close monitoring of levels. The European Network for the Study of Adrenal Tumours (ENSAT) stage at presentation was most predictive of long-term survival with 100% of stage I patients alive compared to 53% of stage II, 25% of stage III and 17% of stage IV patients at the end of the follow-up period.

CONCLUSION

An open en bloc approach with a low threshold for multi-visceral resection performed by high volume surgeons have improved outcomes in local recurrence, operative times and blood loss.

Identification of Five Genes as a Potential Biomarker for Predicting Progress and Prognosis in Adrenocortical Carcinoma

Background: Adrenocortical carcinoma (ACC) is a limited endocrine fatality with a minor diagnosis and rare remedial options. The progressive and predictive meaning of message RNA (mRNA) expression oddity in ACC has been studied extensively in recent years. However, differences in measurement platforms and lab protocols as well as small sample sizes can render gene expression levels incomparable.

Methods: An extensive study of GEO datasets was conducted to define potential mRNA biomarkers for ACC. The study compared the mRNA expression profiles of ACC tissues and neighboring noncancerous adrenal tissues in the pair. The study covered a sum of 165 tumors and 36 benign control samples. Hub genes were identified through a protein-protein interaction (PPI) network and Robust Rank Aggregation method. Then the Cancer Genome Atlas (TCGA) and Oncomine database were used to perform the validation of hub genes. 4 ACC tissues and 4 normal tissues were collected and then Polymerase Chain Reaction (PCR), Western-blot and immunofluorescence were conducted to validate the expression of five hub genes.

Results: We identified five statistically significant genes (TOP2A, NDC80, CEP55, CDKN3, CDK1) corrected with clinical features. The expression of five hub genes in TCGA and Oncomine database were significantly overexpressed in ACC compared with normal ones. Among all the TCGA ACC cases, the strong expression of TOP2A (logrank p=1.4e-04, HR=4.7), NDC80 (logrank p=8.8e-05, HR=4.9), CEP55 (logrank p=5.2e-07, HR=8.6), CDKN3 (log rank p=2.3e-06, HR=7.6) and CDK1 (logrank p=7e-08, HR=11) were correlated with low comprehensive survival, disease free survival (logrank p < 0.001), pathology stage and pathology T stage (FDR < 0.001). PCR results showed that the transcriptional levels of these five genes were significantly higher in ACC tissues than in normal tissues. The western blotting results also showed that the translational level of TOP2A was significantly higher in tumor tissues than in normal tissues. The results of immunofluorescence showed that TOP2A was abundantly observed in the adrenal cortical cell membrane and nucleus and its expression in ACC tissues was significantly higher than that in normal tissues.

Conclusions: The distinguished five genes may be utilized to form a board of progressive and predictive biomarkers for ACC for clinical purpose.

MECHANISMS OF ENDOCRINOLOGY: Cell cycle regulation in adrenocortical carcinoma

Adrenocortical carcinomas (ACCs) are rather rare endocrine tumors that often have a poor prognosis. The reduced survival rate associated with these tumors is due to their aggressive biological behavior, combined with the scarcity of effective treatment options that are currently available. The recent identification of the genomic alterations present in ACC have provided further molecular mechanisms to develop consistent strategies for the diagnosis, prevention of progression and treatment of advanced ACCs. Taken together, molecular and genomic advances could be leading the way to develop personalized medicine in ACCs similarly to similar developments in lung or breast cancers. In this review, we focused our attention to systematically compile and summarize the alterations in the cell cycle regulation that were described so far in ACC as they are known to play a crucial role in cell differentiation and growth. We have divided the analysis according to the major transition phases of the cell cycle, G1 to S and G2 to M. We have analyzed the most extensively studied checkpoints: the p53/Rb1 pathway, CDC2/cyclin B and topoisomerases (TOPs). We reached the conclusion that the most important alterations having a potential application in clinical practice are the ones related to p53/Rb1 and TOP 2. We also present a brief description of on-going clinical trials based on molecular alterations in ACC. The drugs have targeted the insulin-like growth factor receptor 1, TOP 2, polo-like kinase1, cyclin-dependent kinase inhibitors, p53 reactivation and CDC25.

Adrenal Mass: Insight Into Pathogenesis and a Common Link With Insulin Resistance

Adrenal mass (AM) is a common incidental finding detected during radiological investigations with an estimated incidence of 4%. Subjects with AM do not show any physical signs of adrenal hormonal excess, although they are often insulin resistant. Interestingly, apparently nonfunctioning AMs are often associated with a high prevalence of insulin resistance (IR) and metabolic syndrome. However, it is unclear whether AM develops from a primary IR and compensatory hyperinsulinemia or whether IR is only secondary to the slight cortisol hypersecretion by AM. Further, the degree of IR has been directly reported to correlate to the size of AM, thus allowing one to hypothesize that compensatory hyperinsulinemia to IR could be mitogenic on the adrenal cortex acting through the activation of insulin and insulinlike growth factor 1 receptors. Thus, the aim of the present article is to review the current evidence on the link between AM and compensatory hyperinsulinemia to IR.

Pediatric adrenocortical neoplasms: immunohistochemical expression of p57 identifies loss of heterozygosity and abnormal imprinting of the 11p15.5

BACKGROUND

Diagnosis of adrenocortical neoplasms (ACN), in pediatric age, is based on Wieneke criteria. The p57, a cyclin-dependent kinase inhibitor, acts to negatively regulate cell proliferation and is frequently found dysregulated in cancer. The identification of loss of heterozygosity (LOH) of 11p15, containing the p57 gene, could be a tool for differential diagnosis of benign and malignant ACN.

METHODS

Immunohistochemistry with anti-p57 and microsatellite markers analysis of 11p15 region to value LOH were made in both ACN and surrounded normal adrenal cortex.

RESULTS

Nine ACN, two clinically benign, two uncertain, and five malignant, were diagnosed. Positive p57 cells were evident in normal adrenal cortex and in one histologically benign ACN. A low/absent expression of p57 was documented in eight ACN independently from the classification on the basis of pathological and clinical criteria. Microsatellite marker analysis confirmed the LOH of 11p15 region in the same ACN.

CONCLUSION

LOH of 11p15 has a high prognostic value suggesting the p57 gene is important in ACN pathogenesis. Immunohistochemistry for p57 is a simple and cheap tool that can be used to quickly identify LOH of 11p15 in ACN.

[Ectopic adrenal cortical adenoma in the spinal canal: A case report and a review of the literature]

Ectopic adrenal cortical neoplasms are extremely rare. The authors describe their own case of intradural, extramedullary conus medullaris adenoma that occurred in a 55-year-old woman, which was clinically accompanied by lumbar pains, left leg numbness, and left foot weakness during 10 years. The mass was histologically composed of rounded and polygonal cell fields with rounded, regular nuclei and abundant eosinophilic and clear cytoplasm. There were no necroses or mitoses. The cells were immunohistochemically positive for cytokeratin AE1/3, vimentin, inhibin-α, melan-A, and synaptophysin. An ectopic adrenocortical adenoma was diagnosed after ruling out myxopapillary ependymoma, meningioma with oncocytic transformation, paraganglioma, metastatic renal cell carcinoma, and adrenal cortical carcinoma. In the opinion of most investigators, extra-adrenal tumors develop from ectopic adrenal cortical tissue. To date, only eight intraspinal adrenal cortical tumors have been described. These tumors should be considered in the differential diagnosis of central nervous system masses located in the lower spinal canal.

Adrenocortical tumors and insulin resistance: What is the first step?

The pathogenetic mechanisms underlying the onset of adrenocortical tumors (ACTs) are still largely unknown. Recently, more attention has been paid to the role of insulin and insulin-like growth factor (IGF) system on general tumor development and progression. Increased levels of insulin, IGF-1 and IGF-2 are associated with tumor cell growth and increased risk of cancer promotion and progression in patients with type 2 diabetes. Insulin resistance and compensatory hyperinsulinemia may play a role in adrenal tumor growth through the activation of insulin and IGF-1 receptors. Interestingly, apparently non-functioning ACTs are often associated with a high prevalence of insulin resistance and metabolic syndrome. However, it is unclear if ACT develops from a primary insulin resistance and compensatory hyperinsulinemia or if insulin resistance is only secondary to the slight cortisol hypersecretion by ACT. The aim of this review is to summarize the current evidence regarding the relationship between hyperinsulinemia and adrenocortical tumors.

Gene expression and regulation in adrenocortical tumorigenesis

Adrenocortical tumors are frequently found in the general population, and may be benign adrenocortical adenomas or malignant adrenocortical carcinomas. Unfortunately the clinical, biochemical and histopathological distinction between benign and malignant adrenocortical tumors may be difficult in the absence of widely invasive or metastatic disease, and hence attention has turned towards a search for molecular markers. The study of rare genetic diseases that are associated with the development of adrenocortical carcinomas has contributed to our understanding of adrenocortical tumorigenesis. In addition, comprehensive genomic hybridization, methylation profiling, and genome wide mRNA and miRNA profiling have led to improvements in our understanding, as well as demonstrated several genes and pathways that may serve as diagnostic or prognostic markers.

Single nucleotide polymorphism microarray analysis in cortisol-secreting adrenocortical adenomas identifies new candidate genes and pathways

The genetic mechanisms underlying adrenocortical tumor development are still largely unknown. We used high-resolution single nucleotide polymorphism microarrays (Affymetrix SNP 6.0) to detect copy number alterations (CNAs) and copy-neutral losses of heterozygosity (cnLOH) in 15 cortisol-secreting adrenocortical adenomas with matched blood samples. We focused on microalterations aiming to discover new candidate genes involved in early tumorigenesis and/or autonomous cortisol secretion. We identified 962 CNAs with a median of 18 CNAs per sample. Half of them involved noncoding regions, 89% were less than 100 kb, and 28% were found in at least two samples. The most frequently gained regions were 5p15.33, 6q16.1, 7p22.3-22.2, 8q24.3, 9q34.2-34.3, 11p15.5, 11q11, 12q12, 16q24.3, 20p11.1-20q21.11, and Xq28 (≥20% of cases), most of them being identified in the same three adenomas. These regions contained among others genes like NOTCH1, CYP11B2, HRAS, and IGF2. Recurrent losses were less common and smaller than gains, being mostly localized at 1p, 6q, and 11q. Pathway analysis revealed that Notch signaling was the most frequently altered. We identified 46 recurrent CNAs that each affected a single gene (31 gains and 15 losses), including genes involved in steroidogenesis (CYP11B1) or tumorigenesis (CTNNB1, EPHA7, SGK1, STIL, FHIT). Finally, 20 small cnLOH in four cases affecting 15 known genes were found. Our findings provide the first high-resolution genome-wide view of chromosomal changes in cortisol-secreting adenomas and identify novel candidate genes, such as HRAS, EPHA7, and SGK1. Furthermore, they implicate that the Notch1 signaling pathway might be involved in the molecular pathogenesis of adrenocortical tumors.

Adrenal cortical tumors in children: factors associated with poor outcome

PURPOSE

The purpose of this study was to evaluate recurrence and survival outcomes in pediatric adrenal cortical neoplasms.

METHODS

A 90-year retrospective review of children with adrenal cortical neoplasms was performed using multivariate Cox regression analysis to identify factors associated with recurrence and tumor-related mortality.

RESULTS

The evaluable cohort included 29 patients. Twenty-seven underwent resection. Twenty-two (81%) had localized disease, and 5 (19%) had locally advanced disease (all received chemotherapy and 2 of 5 were cured). Two patients presenting with metastatic disease died despite treatment. There were 4 recurrences; all patients died. Tumor-related mortality was 24% (7/29). Kaplan-Meier freedom from recurrence was 85% at 1 year (95% confidence interval, 75%-95%). Multivariate Cox regression revealed that older age (P = .01), higher mitotic rate (P = .005), and necrosis (P < .001) were independent predictors of tumor-related death. Higher mitotic rate (P = .007) and larger tumor size (P = .03) were significant predictors of tumor recurrence.

CONCLUSION

Risk factors for poor outcomes in patients with adrenocortical tumors include older age, higher mitotic rate, higher percent necrosis, and larger tumor size. Therefore, the presence of these factors may warrant consideration of adjuvant chemotherapy, even in the absence of advanced disease.

How is adrenocortical cancer being managed in the UK?

INTRODUCTION

Adrenocortical carcinomas are rare. This case series is reported to give an overview of how adrenocortical carcinoma is currently managed in the UK.

PATIENTS AND METHODS

A retrospective review was made of case notes from patients with adrenocortical carcinomas presenting to the authors (TWJL, RDB, BJH, and DS-C) over the past 10 years in Newcastle, Sheffield and Cardiff.

RESULTS

Newcastle treated twelve, Sheffield eleven and Cardiff seven cases. The median follow-up was 25.5 months (range, 1-102 months). All tumours were greater than 5 cm in diameter. The majority presented with symptoms of hormone excess. Adrenalectomy was performed in 83% - this was radical in 30% and followed by excision of recurrence in 13%. Adjuvant mitotane was given in 64% of patients, in combination with cytotoxic chemotherapy in 20%. One-third of patients did not receive any adjuvant therapy. There was no significant difference in survival between the three centres. The majority of patients (57%) died during the period of follow-up of this study. The median survival was 37 months (range, 2-102 months).

CONCLUSIONS

The size of tumour, stage and mode of presentation, age and overall survival of patients in this study are comparable to published series of adrenocortical carcinomas from major endocrine surgical centres world-wide. Despite controversies about benefits, adjuvant mitotane was used in the majority of cases, whereas cytotoxic chemotherapy was only used in the minority. The exact role of adjuvant therapy in the management of adrenocortical carcinoma is not as well established as for other more common malignancies. Establishing a database for adrenocortical carcinomas in the UK would contribute to our understanding of the management of this disease.

The regulation of non-coding RNA expression in the liver of mice fed DDC

Mallory-Denk bodies (MDBs) are found in the liver of patients with alcoholic and chronic nonalcoholic liver disease, and hepatocellular carcinoma (HCC). Diethyl 1,4-dihydro-2,4,6,-trimethyl-3,5-pyridinedicarboxylate (DDC) is used as a model to induce the formation of MDBs in mouse liver. Previous studies in this laboratory showed that DDC induced epigenetic modifications in DNA and histones. The combination of these modifications changes the phenotype of the MDB forming hepatocytes, as indicated by the marker FAT10. These epigenetic modifications are partially prevented by adding to the diet S-adenosylmethionine (SAMe) or betaine, both methyl donors. The expression of three imprinted ncRNA genes was found to change in MDB forming hepatocytes, which is the subject of this report. NcRNA expression was quantitated by real-time PCR and RNA FISH in liver sections. Microarray analysis showed that the expression of three ncRNAs was regulated by DDC: up regulation of H19, antisense Igf2r (AIR), and down regulation of GTL2 (also called MEG3). S-adenosylmethionine (SAMe) feeding prevented these changes. Betaine, another methyl group donor, prevented only H19 and AIR up regulation induced by DDC, on microarrays. The results of the SAMe and betaine groups were confirmed by real-time PCR, except for AIR expression. After 1 month of drug withdrawal, the expression of the three ncRNAs tended toward control levels of expression. Liver tumors that developed also showed up regulation of H19 and AIR. The RNA FISH approach showed that the MDB forming cells' phenotype changed the level of expression of AIR, H19 and GTL2, compared to the surrounding cells. Furthermore, over expression of H19 and AIR was demonstrated in tumors formed in mice withdrawn for 9 months. The dysregulation of ncRNA in MDB forming liver cells has been observed for the first time in drug-primed mice associated with liver preneoplastic foci and tumors.

Ectopic low-grade adrenocortical carcinoma in the spinal region: immunohistochemical and molecular cytogenetic study of a pediatric case

Ectopic adrenocortical neoplasms arising in the nervous system are very rare. We encountered an intradural, extramedullary case of an adrenocortical neoplasm of indeterminate malignant potential affecting a spinal nerve root in the distal lumbar region of a 5-month-old girl. The lesion recurred 6 months after the initial gross total resection. The tumor in both resections had increased mitotic activity (5/10 high power fields) and MIB-1 labeling indices of 23% and 33% at initial resection and recurrence, respectively. Both tumors demonstrated gains of chromosomes 5 and 12 by interphase cytogenetics, whereas insulin growth factor 2 was identified in the recurrent tumor by immunohistochemistry. This report demonstrates that ectopic adrenocortical tumors in the nervous system may exhibit clinicopathologic and cytogenetic features suggestive of adrenocortical carcinoma.

[Sporadic adrenocortical tumors: genetics and perspectives for the pathologist]

Most adrenocortical tumors are benign; adrenocortical carcinomas are rare but their prognosis is poor and few therapeutic options are available. In most adrenocortical tumors, the morphological approach provides enough elements to establish the differential diagnosis between a benign and a malignant tumor but in few cases, it is insufficient. Moreover, morphology is limited for predicting prognosis of adrenocortical carcinomas. These observations led to development of other approaches, in particular immunohistochemical and genetic approaches. The comprehension of the genetic syndromes associated with adrenocortical tumors led to progress in the identification of genetic abnormalities involved in sporadic adrenocortical tumorigenesis. Thus, in sporadic adrenocortical tumorigenesis, IGF-II overexpression and cyclin E overproduction have been associated with 11p15 alterations which are observed in Bethwith-Wiedemann syndrome and TP53 inactivating mutations and 17p13 locus abnormalities which are observed in Li-Fraumeni syndrome. Activation of the Wnt/ss-catenin signaling pathway which is observed in familial adenomatous polyposis has been found in adrenocortical adenomas and carcinomas associated to mutations of CTNNB1, the gene coding ss-catenin, suggesting a central role for this pathway in adrenocortical tumorigenesis. These genetics findings already have had repercussions for patients via the development of molecular markers for diagnosis and prognosis; in the future they should be helpful in the development of new therapeutics.

Discerning malignancy in resected adrenocotical tumors

BACKGROUND

The number of adrenocortical tumors discovered incidentally has recently increased owing to the advent of imaging techniques. The most important diagnostic point in evaluation of resected specimens of these tumors is to discern malignancy to determine postoperative management of the patients.

OBJECTIVE/METHODS

To determine what the effective methods of discerning malignancy in resected specimens of adrenocortical tumors are at this juncture. To provide relevant and practical information pertinent to those involved in the management of patients with adrenocortical tumors.

CONCLUSION

Careful macroscopic evaluation, including the selection of the specimens submitted and application of the criteria of Weiss for histological diagnosis, is still considered the 'gold standard' for diagnosis of adrenocortical carcinoma. However, it is important to recognize its limitations in the diagnosis of adrenocortical oncocytoma and pediatric adrenocortical tumors. The auxiliary methods that may be of clinical relevance at this juncture include the analysis of the Ki67/MIB-1 labeling index and IGF-II expression in the tumors.

Metastatic adrenocortical oncocytoma: a case report

With only 51 cases reported in the literature to date, adrenocortical oncocytoma is an exceedingly rare pathological variant of adrenal neoplasms. The first case of metastatic adrenocortical oncocytoma is reported along with an update of the literature. A role for radiotherapy in the palliative setting is demonstrated.

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.

Lack of association between microsatellite instability and benign adrenal tumors

BACKGROUND

The adrenal gland may give rise to pheochromocytomas, which are catecholamine-producing tumors originating from the adrenal medulla, or to adrenocortical tumors, which derive from the adrenocortical cortex and may be secreting or not. The genetic mechanisms underlying the formation of these tumors include somatic mutations in susceptibility genes, especially in the familial forms, and allelic loss, especially in chromosome 1.

AIM

The aim of this study was to investigate a third genetic mechanism by evaluating microsatellite instability using the reference markers (Bat25, Bat26, D2S123, D5S346, D17S250) validated by the National Cancer Institute. Microsatellite loci were analyzed in 32 benign tumors, including 11 pheochromocytomas and 21 adrenocortical tumors, in patients with and without familial syndrome.

RESULTS

The different alleles of microsatellite loci were reliably detected by DNA fragments analysis, whereas data obtained after melting-point analysis on the Lightcycler were inconsistent. No microsatellite instability was detected in any tumor. One patient with a unilateral pheochromocytoma showed a loss of heterozygosity for D17S250. A second patient with a MEN-2A syndrome and a two-sided pheochromocytoma exhibited a loss of heterozygosity for D2S123 in the right tumor only and a retention of heterozygosity for all markers in the left tumor.

CONCLUSIONS

These results suggest that microsatellite instability, evaluated by the five reference markers of the National Cancer Institute, is not a feature of benign adrenal tumors.

Childhood adrenocortical tumours: a review

Childhood adrenocortical tumour (ACT) is not a common disease, but in southern Brazil the prevalence is 15 times higher than in other parts of the world. One hundred and thirty-seven patients have been identified and followed by our group over the past four decades. Affected children are predominantly girls, with a female-to-male ratio of 3.5:1 in patients below 4 years of age. Virilization alone (51.6%) or mixed with Cushing's syndrome (42.0%) was the predominant clinical picture observed in these patients. Tumours are unilateral, affecting both glands equally. TP53 R337H germline mutations underlie most childhood ACTs in southern Brazil. Epidemiological data from our casuistic studies revealed that this mutation has ~10% penetrance for ACT. Surgery is the definitive treatment, and a complete resection should always be attempted. Although adjuvant chemotherapy has shown some encouraging results, its influence on overall outcome is small. The survival rate is directly correlated to tumour size; patients with small, completely excised tumours have survival rates close to 90%, whereas in those patients with inoperable tumours and/or metastatic disease it is less than 10%. In the group of patients with large, excisable tumours, half of them have an intermediate outcome. Recent molecular biology techniques and genomic approaches may help us to better understand the pathogenesis of ACT, the risk of developing a tumour when TP53 R337H is present, and to predict its outcome. An ongoing pilot study consisting of close monitoring of healthy carriers of the TP53 R337H mutation - siblings and first-degree relatives of known affected cases - aims at the early detection of ACTs and an improvement of the cure rate.

Recent advances in histopathology and immunohistochemistry of adrenocortical carcinoma

Discerning malignancy in resected adrenocortical neoplasms can pose diagnostic difficulty. Macroscopic examination is the first important step toward diagnosis and should include accurate measurement of weight and dimension of the specimens and description of the cut surface of the tumors. It is also important to sample the specimens for histological diagnosis near foci of hemorrhage and/or necrosis. Histological scoring systems evaluating multiple parameters, especially the criteria of Weiss, have been shown to be reliable in differential diagnosis between adrenocortical adenoma and carcinoma. A tumor is defined as adrenocortical carcinoma when three or more of the following criteria are met; (1) high nuclear grade, (2) mitotic rate six or more per 50 high power fields, (3) atypical mitosis, (4) clear cells less than 25%, (5) a diffuse architecture pattern in more than one-third of the tumor, (6) confluent necrosis, (7) venous invasion, (8) sinusoidal invasion, and (9) capsular invasion. The criteria are relatively straightforward and considered the most effective standard for diagnosis of adrenocortical malignancy. However, great care should be taken in applying the criteria to histological evaluation of two relatively rare and peculiar adrenocortical tumors, adrenocortical oncocytoma and pediatric adrenocortical neoplasms. At this juncture, ancillary biological or molecular markers are of little practical value in terms of differential diagnosis between adrenocortical adenoma and carcinoma but tumors with MIB1 or Ki-67 labeling index more than 2.5 may be considered malignant. Prognostic markers of adrenocortical carcinoma have not been established other than complete respectability of the tumor. There are also no surrogate markers for predicting response to therapy with Mitotane, an adrenolytic agent. It sometimes is important for surgical pathologists to differentiate adrenocortical carcinoma from metastatic malignancies of other sites. An immunohistochemical evaluation of adrenal 4 binding protein (Ad4BP) or SF-1, a transcription factor of all steroidogenesis, can aid in this differential diagnosis because nuclear immunoreactivity for this transcription factor is relatively specific to steroid producing cells.

Unusual adrenal cortical tumor of unknown biologic potential: a nodule in a nodule in a nodule

Adrenocortical tumors are uncommon neoplasms in childhood. Most pediatric adrenal tumors are virilizing and carcinomas are more common than adenomas. Recent molecular data suggest an adenoma-to-carcinoma progression sequence in adrenal cortical neoplasms. We report a case of a 5-year-old boy who presented with virilizing symptoms secondary to an adrenal tumor that was resected laparoscopically. The bulk of the tumor was a large, yellow mass with typical features of an adrenal cortical adenoma. In the center was a well-circumscribed tan-brown nodule that was distinct from the adenoma and had oncocytic features. A third minute focus (3.0 mm) was noted that was not circumscribed or encapsulated, but showed marked pleomorphism and abundant mitoses, including atypical forms and increased Ki67 compared with the outer 2 nodules. Molecular analysis to assess the clonality and mutation rates of the 3 distinct areas showed only 2 genetic loci with allelic imbalances.

Adrenocortical cancer: recent clinical and molecular advances

PURPOSE OF REVIEW

Adrenocortical cancer (ACC) is an uncommon disorder that remains a challenge to the surgeon and oncologist. When the disease is localized to the adrenal gland and readily amenable to surgical resection, reasonable 5-year survival rates are possible. Locally invasive disease carries a poorer prognosis, and metastatic disease is uniformly fatal within 1 year. In this review, we summarize the current knowledge regarding the clinical management of ACC and the molecular mechanisms underlying the disease.

RECENT FINDINGS

The clinical manifestations, staging, and current treatment for ACC has been well documented. Surgery is still the mainstay of treatment, but identifying molecular targets for chemotherapeutic agents or monoclonal antibodies would be a great advance. At present, our understanding of pathogenic mechanisms is crude; however, the molecular events regulating this aggressive disease are beginning to emerge, especially in the last few years. The advent of laparoscopic adrenalectomy has also created its own dilemmas regarding the appropriate surgical approach to the large, potentially malignant adrenal mass.

SUMMARY

The challenge in the management of this disease lies in understanding the molecular mechanisms that underlie the development of ACC with the diagnostic and therapeutic benefits that would ensue.