Clinicopathological study of a series of 92 adrenocortical carcinomas: from a proposal of simplified diagnostic algorithm to prognostic stratification

Prognostic factors in stage III-IV adrenocortical carcinomas (ACC): an European Network for the Study of Adrenal Tumor (ENSAT) study

BACKGROUND

The clinical course of advanced adrenocortical carcinoma (ACC) is heterogeneous. Our study aimed primarily to refine and make headway in the prognostic stratification of advanced ACC.

PATIENTS AND METHODS

Patients with advanced ENSAT ACC (stage III or stage IV) at diagnosis registered between 2000 and 2009 in the ENSAT database were enrolled. The primary end point was overall survival (OS). Parameters of potential prognostic relevance were selected. Univariate and multivariate analyses were carried out: model 1 'before surgery'; model 2 'post-surgery'.

RESULTS

Four hundred and forty-four patients with advanced ENSAT ACC (stage III: 210; stage IV: 234) were analyzed. After a median follow-up of 55.2 months, the median OS was 24 months. A modified ENSAT (mENSAT) classification was validated: stage III (invasion of surrounding tissues/organs or the vena renalis/cava) and stage IVa, IVb, IVc (2, 3 or >3 metastatic organs, including N, respectively). Two- or 5-year OS was 73%, 46%, 26% and 15% or 50%, 15%, 14% and 2% for stages III, IVa, IVb and IVc, respectively. In the multivariate analysis, mENSAT stages (stages IVa, IVb, or IVc, respectively) were significantly correlated with OS (P < 0.0001), as well as additional parameters: age ≥ 50 years (P < 0.0001), tumor- or hormone-related symptoms (P = 0.01 and 0.03, respectively) in model 1 but also the R status (P = 0.001) and Grade (Weiss >6 and/or Ki67 ≥ 20%, P = 0.06) in model 2.

CONCLUSION

The mENSAT classification and GRAS parameters (Grade, R status, Age and Symptoms) were found to best stratify the prognosis of patients with advanced ACC.

Adrenocortical carcinoma: modern management and evolving treatment strategies

Adrenocortical carcinoma (ACC) is a rare cancer with a poor prognosis. Unlike many other cancers, there has been little improvement in patient outcome over the past several decades. However, as scientific advancements are made and our understanding of the molecular genetics involved in ACC improve then progress may be achieved in this devastating disease. This review focuses on recent literature published in the field of ACC from 2010 to 2015 with an emphasis on improving diagnosis, staging and treatment for ACC.

Surgical Management of Adrenocortical Carcinoma: An Evidence-Based Approach

Adrenocortical carcinoma frequently presents with sequelae of steroid precursor overproduction and has a proclivity for aggressive local growth, early metastasis, and recurrence. En bloc surgical resection with negative margins is the cornerstone of therapy for localized disease, and re-resection has a role in selected recurrent cases. Presence of occult micrometastatic disease at the time of presentation is confirmed by frequent distant failure after apparent negative margin resection. Data for many aspects of therapy are limited or nonexistent. This review critically considers existing evidence with a particular focus on surgical management.

Clinicopathologic Correlates of Primary Aldosteronism

Primary aldosteronism is the most common cause of secondary hypertension, incurring significant cardiovascular morbidity and mortality. Our understanding of this disease has evolved substantially during the past decade. Recently, the molecular basis of primary aldosteronism has begun to be unraveled, with the discovery of mutations in potassium channel (KCNJ5), ATPases (ATP1A1, ATP2B3), and calcium channel (CACNA1D), and aberrant Wnt/β-catenin signaling. The most recent data suggest that 95% of cases are sporadic, whereas 5% of cases are hereditary. Pathologic correlates of primary aldosteronism include adrenal cortical hyperplasia, adenoma, and carcinoma. Although the most common clinical presentation is bilateral adrenal cortical hyperplasia, this entity is usually treated medically. Therefore, in the setting of primary aldosteronism, surgical pathologists are most commonly exposed to adrenocortical adenomas and the odd occasional carcinoma. This review provides an update on the current knowledge of primary aldosteronism and discusses the clinicopathologic correlations of this important disease.

Clinicopathological correlates of adrenal Cushing's syndrome

Endogenous Cushing's syndrome is a rare endocrine disorder that incurs significant cardiovascular morbidity and mortality, due to glucocorticoid excess. It comprises adrenal (20%) and non-adrenal (80%) aetiologies. While the majority of cases are attributed to pituitary or ectopic corticotropin (ACTH) overproduction, primary cortisol-producing adrenal cortical lesions are increasingly recognised in the pathophysiology of Cushing's syndrome. Our understanding of this disease has progressed substantially over the past decade. Recently, important mechanisms underlying the pathogenesis of adrenal hypercortisolism have been elucidated with the discovery of mutations in cyclic AMP signalling (PRKACA, PRKAR1A, GNAS, PDE11A, PDE8B), armadillo repeat containing 5 gene (ARMC5) a putative tumour suppressor gene, aberrant G-protein-coupled receptors, and intra-adrenal secretion of ACTH. Accurate subtyping of Cushing's syndrome is crucial for treatment decision-making and requires a complete integration of clinical, biochemical, imaging and pathology findings. Pathological correlates in the adrenal glands include hyperplasia, adenoma and carcinoma. While the most common presentation is diffuse adrenocortical hyperplasia secondary to excess ACTH production, this entity is usually treated with pituitary or ectopic tumour resection. Therefore, when confronted with adrenalectomy specimens in the setting of Cushing's syndrome, surgical pathologists are most commonly exposed to adrenocortical adenomas, carcinomas and primary macronodular or micronodular hyperplasia. This review provides an update on the rapidly evolving knowledge of adrenal Cushing's syndrome and discusses the clinicopathological correlations of this important disease.

Adrenocortical carcinoma

Recent developments in the treatment of adrenocortical carcinoma (ACC) include diagnostic and prognostic risk stratification algorithms, increasing evidence of the impact of historical therapies on overall survival, and emerging targets from integrated epigenomic and genomic analyses. Advances include proper clinical and molecular characterization of all patients with ACC, standardization of proliferative index analyses, referral of these patients to large cancer referral centers at the time of first surgery, and development of new trials in patients with well-characterized ACC. Networking and progress in the molecular characterization of ACC constitute the basis for significant future therapeutic breakthroughs.

Diagnostic and prognostic features in adrenocortical carcinoma: a single institution case series and review of the literature

Background

Adrenocortical carcinoma is a rare cancer, with an incidence in the literature of 0.5 to 2 cases per million population per year. Adult adrenocortical carcinoma has a poor prognosis, underscoring the importance of identifying diagnostic and prognostic markers.

Methods

We searched our laboratory database for all cases in the past 15 years with a diagnosis of adrenocortical carcinoma. The original slides were then reviewed for their histopathological features. A representative paraffin block was subjected to further immunohistochemical staining for Ki-67, inhibin, steroidogenic factor-1 (SF-1), p53, and Β-catenin. These slides were scored by the study pathologist who was blinded to all clinicopathological data. In addition, a comprehensive review of the relevant English literature in the past 15 years was conducted.

Results

Eight cases were identified, including two adrenal sarcomatoid carcinomas. Seven of the eight cases had a disrupted reticulin network. Six of the eight tumors had >10% Ki-67 expression. Five of the eight tumors had >10% p53 expression. Positive inhibin immunohistochemical staining was seen in three of the eight tumors, and positive SF-1 staining was seen in five of the seven stained tumors. Abnormal Β-catenin intracellular accumulation was noted in four of the eight tumors. The two tumors in our series with sarcomatoid histology did not stain positively for SF-1 or inhibin.

Conclusions

Eight cases of adrenocortical carcinoma, including two with sarcomatoid features are presented. The two sarcomatoid adrenocortical carcinomas in our series did not stain for SF-1 which suggests a possible de novo pathway of tumorigenesis for this rare variant. The reticulin staining method was a useful tool for rapid differentiation of adrenocortical adenomas and carcinomas. Diffuse p53 staining showed a trend for positive correlation with increased Ki-67 expression. Inhibin staining was inconsistently expressed in our cases of adrenocortical carcinoma. In conclusion, as adrenocortical carcinoma is a rare disease, we recommend future multicenter studies with appropriate sample sizes to further evaluate the efficacy of these diagnostic and prognostic markers.

Genomic and immunohistochemical analysis in human adrenal cortical neoplasia reveal beta-catenin mutations as potential prognostic biomarker

Evaluation for malignancy of the adrenal cortex, adrenal cortical carcinoma (ACC), is a challenge in surgical pathology due to its relative rarity and histologic overlap with its benign counterpart, adrenocortical adenoma (ACA). We characterized a cohort of human ACC and ACA, including a molecular screen, with a goal of identifying potential diagnostic adjuncts. Thirty-six cases of ACC underwent histologic and clinical review. In the 31 ACC cases with available material and a cohort of 10 ACA cases, a multiplex nucleotide amplification molecular screen from formalin-fixed, paraffin-embedded tissue was peformed. ACCs demonstrated a wide variety of clinical and histologic characteristics with overall poor but unpredictable survival for subjects with ACC. By mutational screen, 12/31 (38.7%) carcinomas harbored CTNNB1 mutations, 1 with an additional TP53 mutation; 1 case each had isolated APC and TP53 mutations; 16 were wild-type for all tested loci; and 1 case demonstrated repeated assay failures. Two of the 10 ACA (20%) demonstrated CTNNB1 mutations by mutational screen, with no additional mutations. Immunohistochemistry for beta-catenin was performed and compared with the results of the molecular screen. Strong nuclear beta-catenin immunopositivity corresponded to the presence of CTNNB1 mutation by genotyping in 10 of 12 cases (83% sensitivity); the mismatched case(s) demonstrated strong membranous staining by immunohistochemistry. Seventeen of the 18 cases without CTNNB1 mutation showed membranous staining or did not stain (94% specificity); the mismatched case demonstrated scattered (<10%) positive nuclei. Both mutations in ACA were corroborated with immunohistochemistry for beta-catenin. No histomorphologic parameter appeared dominant in lesions with a particular mutational status. Based on these results, mutational status of CTNNB1 in adrenal cortical neoplasms can be predicted with reasonable accuracy by immunohistochemical cellular localization. Nuclear localization of beta-catenin by immunostain may be helpful in analysis of select lesions of the adrenal cortex whose biological behavior is uncertain from clinical and histologic information; a larger cohort is required to test this hypothesis.

Assessing Biological Aggression in Adrenocortical Neoplasia

Pathologists are highly skilled at the evaluation of adrenal neoplasms. Occasional adrenocortical tumors can be diagnostically challenging and supplementary tools can assist in these cases. Histologic and molecular studies support a model that includes 2 broad classes of adrenocortical carcinoma with distinct somatic genetic alterations and clinical outcomes. Pathologists should endeavor to grade adrenocortical carcinomas to assign each case into one of these 2 classes. Mitotic grading by mitotic counting and Ki-67 immunohistochemistry represent the most practicable and informative methods currently available.

Comparative diagnostic and prognostic performances of the hematoxylin-eosin and phospho-histone H3 mitotic count and Ki-67 index in adrenocortical carcinoma

Mitotic count on hematoxylin and eosin slides is a fundamental morphological criterion in the diagnosis and grading of adrenocortical carcinoma in any scoring system employed. Moreover, it is the unique term strongly associated with patient's prognosis. Phospho-histone H3 is a mitosis-specific antibody, which was already proven to facilitate mitotic count in melanoma and other tumors. Therefore, a study was designed to assess the diagnostic and prognostic role of phospho-histone H3 in 52 adrenocortical carcinomas, comparing manual and computerized count to standard manual hematoxylin- and eosin-based method and Ki-67 index. Manual hematoxylin and eosin and phospho-histone H3 mitotic counts were highly correlated (r=0.9077, P<0.0001), better than computer-assisted phospho-histone H3 evaluations, and had an excellent inter-observer reproducibility at Bland-Altman analysis. Three of 15 cases having <5 mitotic figures per 50 high-power fields by standard count on hematoxylin and eosin gained the mitotic figure point of Weiss Score after a manual count on phospho-histone H3 slides. Traditional mitotic count confirmed to be a strong predictor of overall survival (P=0.0043), better than phospho-histone H3-based evaluation (P=0.051), but not as strong as the Ki-67 index (P<0.0001). The latter further segregated adrenocortical carcinomas into three prognostic groups, stratifying cases by low (<20%), intermediate (20-50%), and high (>50%) Ki-67 values. We conclude that (a) phospho-histone H3 staining is a useful diagnostic complementary tool to standard hematoxylin and eosin mitotic count, enabling optimal mitotic figure evaluation (including atypical mitotic figures) even in adrenocortical carcinomas with a low mitotic index and with a very high reproducibility; (b) Ki-67 proved to be the best prognostic indicator of overall survival, being superior to the mitotic index, irrespective of the method (standard on hematoxylin and eosin or phospho-histone H3-based) used to count mitotic figures.

Adrenocortical carcinoma: what the surgeon needs to know. Case report and literature review

Adrenocortical carcinoma is a rare and aggressive cancer and its prognosis is frequently unsatisfactory. Due to its rarity there's a lack of prospective randomized studies. Without experience in the approach of this kind of tumor, managing becomes challenging and, moreover, we have only few recommendations, based on weak evidence. We report a case that has some peculiarities and is an excellent food for thought. Then we deal with a literature review to highlight and summarize most significant aspects of epidemiology, clinic, diagnosis, therapy and prognosis in an exquisitely surgical point of view.

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.

Management of adrenal cancer: a 2013 update

Adrenocortical carcinoma (ACC) is a devastating tumor for either patients or their families because of short life expectancy and severe impact on quality of life. Due to the rarity of ACC, with a reported annual incidence of 0.5-2 cases per million population, progress in the development of treatment options beyond surgery has been limited. Up to now, no personalized approach of ACC therapy has emerged, apart from plasma level-guided mitotane therapy, and no simple targetable molecular event has been identified from preclinical studies. Complete surgical removal of ACC is the only potentially curative approach and has the most important impact on patient’s prognosis. Despite the limits of the available evidence, adjuvant mitotane therapy is currently recommended in many expert centers whenever the patients present an elevated risk of recurrence. The management of patients with recurrent and metastatic disease is challenging and the prognosis is often poor. Mitotane monotherapy is indicated in the management of patients with a low tumor burden and/or more indolent disease while patients whose disease show an aggressive behavior need cytotoxic chemotherapy. The treatment of patients with advanced ACC may include loco-regional approaches such as surgery and radiofrequency ablation in addition to systemic therapies. The present review provides an updated overview of the management of ACC patients following surgery and of the management of ACC patients with advanced disease.

Pathology of the adrenal cortex: a reappraisal of the past 25 years focusing on adrenal cortical tumors

A reappraisal of the major advances in the diagnostic pathology of adrenal cortical lesions and tumors in the last 25 years is presented, with special reference to the definition of malignancy in primary adrenal cancer and its variants. Slightly more than 25 years ago, Weiss proposed his diagnostic scoring system for adrenal cortical carcinoma. This represented a milestone for adrenal pathologists and the starting point for further modifications of the system, either through minor changes in the scoring procedure itself or concentrating on some particular Weiss criterion such as mitotic index, integrated into alternative scoring schemes or algorithms that are currently under validation. Improvements in diagnostic immunohistochemistry have led to the identification of markers of cortical origin, such as Melan-A, alpha-inhibin, and SF-1 and of prognostic factors in carcinoma, such as the Ki-67 proliferation index and SF-1 itself. With regard to hyperplastic conditions, genetic investigations have allowed the association of the majority of cases of primary pigmented nodular adrenocortical disease (PPNAD) in Carney complex to mutations in the gene encoding the regulatory subunit 1A of protein kinase A (PRKAR1A). Other hereditary conditions are also associated with adrenal cortical tumors, including the Li-Fraumeni, Beckwith-Wiedemann, Gardner, multiple endocrine neoplasia type 1, and neurofibromatosis type 1 syndromes. Moreover, several advances have been made in the knowledge of the molecular background of sporadic tumors, and a number of molecules/genes are of particular interest as potential diagnostic and prognostic biomarkers.

1α,25-Dihydroxyvitamin D₃ inhibits the human H295R cell proliferation by cell cycle arrest: a model for a protective role of vitamin D receptor against adrenocortical cancer

Using the human H295R adrenocortical carcinoma cell line as a model, we analyzed the role of 1α,25-dihydroxyvitamin D₃ [1α,25(OH)₂D₃)]--vitamin D receptor (VDR) axis in the growth of adrenocortical cancer (ACC). The presence of VDR in various adrenocortical tissues, including ACC, was also investigated. DNA synthesis was evaluated by [³H]thymidine cell incorporation after treatment with 1α,25(OH)₂D₃ at increasing doses. The effect of 1α,25(OH)₂D₃ on cell cycle and apoptosis was analyzed with a flow cytometer. Cyclin-dependent kinase 4 (CDK4) expression, a molecular marker of G1-S cell cycle transition phase, was evaluated in cells treated with 1α,25(OH)₂D₃ before and after VDR gene silencing. 1α,25(OH)₂D₃ treatment inhibited cell proliferation by 20% at a dose of 1 nM, in parallel with steroid secretion decrease. A cell cycle arrest in G1, with no change in apoptotic cell proportion, was observed after 10 nM 1α,25(OH)₂D₃ cell exposure. CDK4 activation was reduced by 10 nM 1α,25(OH)₂D₃ but was not affected by 1α,25(OH)₂D₃ after VDR gene silencing. Expression of VDR mRNA was lower in ACC than in benign adrenocortical tumors. VDR immunostaining was evident in benign tumors but it was weak in ACC tissues.

CONCLUSIONS

Slightly supra-physiological concentrations of 1α,25(OH)₂D₃ have a moderate anti-proliferative effect on H295R cells. Anti-proliferative effect was due to cell cycle arrest in G1 phase, without inducing apoptosis. The low mRNA expression levels at qRT-PCR as well as the weak immunohistochemical expression of VDR in ACC, suggests a protective role of VDR against malignant adrenocortical growth.

Adjuvant therapies and patient and tumor characteristics associated with survival of adult patients with adrenocortical carcinoma

CONTEXT

Adrenocortical carcinoma is a rare malignant endocrine neoplasia. Studies regarding outcome and prognostic factors rely on fairly small studies. Here we summarize the experience with patients with a diagnosis of adrenocortical carcinoma from a large tertiary referral center.

OBJECTIVE

The objective of the study was to identify prognostic factors in patients with adrenocortical carcinoma and evaluate adjuvant treatment strategies.

DESIGN

Patient data were collected in a retrospective single-center study. Epidemiological, patient, and tumor characteristics were analyzed for prognostic factors regarding overall and recurrence-free survival in Cox regression models (multivariable and univariable).

RESULTS

Three hundred ninety-one adult patients with the diagnosis of adrenocortical carcinoma were identified. Median overall survival was 35.2 months. Cortisol production [hazard ratio (HR) 1.4, HR 1.5], tumor stage (HR stage 3 of 2.1 and 2.1, HR stage 4 of 4.8), and tumor grade (HR 2.4 and 2.0) were identified as negative prognostic factors (HR for death, HR for recurrence). Mitotane therapy increases recurrence-free survival, an effect that was significantly further improved by adjuvant radiation therapy but did not impact overall survival. Patients with open adrenalectomy had improved overall survival.

CONCLUSIONS

This study increases the evidence for adverse risk factors (cortisol production, high tumor stage, and high tumor grade) and suggests the following therapy approach: adrenocortical carcinoma patients should be treated with open adrenalectomy. Adjuvant therapy, particularly mitotane therapy in conjunction with radiation, should be considered to delay tumor recurrence.

Update in adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is an orphan malignancy that has attracted increasing attention during the last decade. Here we provide an update on advances in the field since our last review published in this journal in 2006. The Wnt/β-catenin pathway and IGF-2 signaling have been confirmed as frequently altered signaling pathways in ACC, but recent data suggest that they are probably not sufficient for malignant transformation. Thus, major players in the pathogenesis are still unknown. For diagnostic workup, comprehensive hormonal assessment and detailed imaging are required because in most ACCs, evidence for autonomous steroid secretion can be found and computed tomography or magnetic resonance imaging (if necessary, combined with functional imaging) can differentiate benign from malignant adrenocortical tumors. Surgery is potentially curative in localized tumors. Thus, we recommend a complete resection including lymphadenectomy by an expert surgeon. The pathology report should demonstrate the adrenocortical origin of the lesion (eg, by steroidogenic factor 1 staining) and provide Weiss score, resection status, and quantitation of the proliferation marker Ki67 to guide further treatment. Even after complete surgery, recurrence is frequent and adjuvant mitotane treatment improves outcome, but uncertainty exists as to whether all patients benefit from this therapy. In advanced ACC, mitotane is still the standard of care. Based on the FIRM-ACT trial, mitotane plus etoposide, doxorubicin, and cisplatin is now the established first-line cytotoxic therapy. However, most patients will experience progress and require salvage therapies. Thus, new treatment concepts are urgently needed. The ongoing international efforts including comprehensive "-omic approaches" and next-generation sequencing will improve our understanding of the pathogenesis and hopefully lead to better therapies.

Mitotane levels predict the outcome of patients with adrenocortical carcinoma treated adjuvantly following radical resection

CONTEXT

Mitotane plasma concentrations ≥ 14 mg/l have been shown to predict tumor response and better survival in patients with advanced adrenocortical carcinoma (ACC). A correlation between mitotane concentrations and patient outcome has not been demonstrated in an adjuvant setting.

OBJECTIVE

To compare recurrence-free survival (RFS) in patients who reached and maintained mitotane concentrations ≥ 1 4 mg/l vs patients who did not.

DESIGN AND SETTING

Retrospective analysis at six referral European centers.

PATIENTS

Patients with ACC who were radically resected between 1995 and 2009 and were treated adjuvantly with mitotane targeting concentrations of 14-20 mg/l.

MAIN OUTCOME MEASURES

RFS (primary) and overall survival (secondary).

RESULTS

Of the 122 patients included, 63 patients (52%) reached and maintained during a median follow-up of 36 months the target mitotane concentrations (group 1) and 59 patients (48%) did not (group 2). ACC recurrence was observed in 22 patients of group 1 (35%) and 36 patients in group 2 (61%). In multivariable analysis, the maintenance of target mitotane concentrations was associated with a significantly prolonged RFS (hazard ratio (HR) of recurrence: 0.418, 0.22-0.79; P=0.007), while the risk of death was not significantly altered (HR: 0.59, 0.26-1.34; P=0.20). Grades 3-4 toxicity was observed in 11 patients (9%) and was managed with temporary mitotane discontinuation. None of the patients discontinued mitotane definitively for toxicity.

CONCLUSIONS

Mitotane concentrations ≥ 14 mg/l predict response to adjuvant treatment being associated with a prolonged RFS. A monitored adjuvant mitotane treatment may benefit patients after radical removal of ACC.

A Case of Myxoid Adrenocortical Neoplasm: Computed Tomography and Magnetic Resonance Imaging Characteristics

Myxoid adrenocortical neoplasms are rare; to our knowledge, only 56 cases have been reported in the literature. Therefore, distinguishing benign from malignant cases is challenging. Although the histopathological features of myxoid adrenocortical neoplasia have been amply demonstrated, their imaging characteristics are yet to be reported. We describe here these characteristics for such a neoplasm. Our patient, a 70-year-old male, was found to have a 3-cm left adrenal incidentaloma through a non-enhanced computed tomography. Attenuation measurements were 22 Hounsfield units on precontrast imagery, and percentage enhancement washout was 92%. Magnetic resonance imaging showed no loss of signal intensity in T1-weighted out-of-phase images, but high signal intensity on T2-weighted and diffusion-weighted images. Left adrenalectomy was performed and the pathological diagnosis was confirmed as myxoid adrenocortical neoplasm. The imaging characteristics reported here will be beneficial to the differential diagnosis of myxoid adrenocortical neoplasms based upon image analysis and will help distinguish benign from malignant neoplasms.

Primary rhabdoid adrenocortical carcinoma: a clinicopathological and immunohistochemical study of three cases

AIMS

We describe three cases of primary adrenocortical carcinoma (ACC) with prominent rhabdoid features and study their clinicopathological and immunohistochemical properties.

METHODS AND RESULTS

The patients were three females aged 45-55 years (mean 49 years), none of whom had any hormone-related symptoms. Histologically, the characteristic features were rhabdoid tumour cells with prominent eosinophilic cytoplasmic inclusions, eccentric vesicular nuclei and prominent nucleoli. Areas of more conventional ACC were present in all cases. Immunohistochemically, the rhabdoid component showed a similar staining pattern to conventional ACC, being positive for steroid receptor cofactor 1, inhibin, melan A, calretinin and synaptophysin, while negative for high molecular weight cytokeratin and Pax8. In addition, antimitochondrial antibodies showed a weak reaction and nuclear expression of integrase interactor 1 (INI1) was preserved. Clinical follow-up information for two patients demonstrated that one patient was alive 237 months after diagnosis, and one patient had died of disease 4 months after diagnosis.

CONCLUSIONS

ACC with rhabdoid features are rare tumours that seem to mirror the clinical and immunohistochemical features of conventional ACC. In addition, they appear to display similar biological behaviour. Adrenocortical carcinoma should be included in the differential diagnosis when evaluating tumours of unknown origin with rhabdoid morphology.

Management of adjuvant mitotane therapy following resection of adrenal cancer

Whenever adrenal cancer (ACC) is completely removed we should face the dilemma to treat by means of adjuvant therapy or not. In our opinion, adjuvant mitotane is the preferable approach in most cases because the majority of patients following radical removal of an ACC have an elevated risk of recurrence. A better understanding of factors that influence prognosis and response to treatment will help in stratifying patients according to their probability of benefiting from adjuvant mitotane, with the aim of sparing unnecessary toxicity to patients who are likely unresponsive. However, until significant advancements take place, we have to deal with uncertainty using our best clinical judgement and personal experience in the clinical decision process. In the present paper, we present the current evidence on adjuvant mitotane treatment and describe the management strategies of patients with ACC after complete surgical resection. We acknowledge the limit that most recommendations are based on personal experience rather than solid evidence.

Diagnostic and prognostic role of steroidogenic factor 1 in adrenocortical carcinoma: a validation study focusing on clinical and pathologic correlates

The pathologic characterization of adrenocortical cancer is still problematic for several reasons, including the identification of novel markers of diagnostic or prognostic relevance. Among them, steroidogenic factor 1 deserves major interest because of its potential usefulness as a marker of adrenocortical derivation and of biological aggressiveness. Our aim was to validate its prognostic relevance in a large series of adrenocortical cancer, comparing the performance of 2 different commercial antibodies and investigating its expression in adrenocortical cancer variants and in comparison with clinical and pathologic features. Seventy-five (including 53 classical, 10 myxoid, and 12 oncocytic) adrenocortical cancer cases were included in tissue microarrays and analyzed for the immunohistochemical expression of steroidogenic factor 1 using 2 commercial antibodies, 1 polyclonal and 1 monoclonal (N1665). Nuclear steroidogenic factor 1 staining was assessed using a semiquantitative score and correlated with adrenocortical cancer type and clinical pathologic characteristics. A weak but significant correlation was found comparing the 2 antibodies with a positive rate of 88% and 58% using the monoclonal and polyclonal antibodies, respectively. High steroidogenic factor 1 expression with the N1665 antibody was positively correlated with high mitotic count, high Ki-67 index, and high European Network for the Study of Adrenal Tumors (ENSAT) stage and negatively associated with loss of functionality and presence of oncocytic features. Moreover, high steroidogenic factor 1 expression with this same antibody was significantly associated at univariate analysis with a decreased survival, together with high Ki-67 and mitotic indexes, with a trend to significance confirmed by multivariate analysis, thus supporting the detection of steroidogenic factor 1 using the N1665 antibody as a novel prognostic marker in adrenocortical cancer.

Ribonucleotide reductase large subunit (RRM1) gene expression may predict efficacy of adjuvant mitotane in adrenocortical cancer

PURPOSE

Mitotane is the most broadly used systemic therapy for adrenocortical carcinoma (ACC), but its mechanism of action and possible predictors of treatment response are currently poorly defined. Our aim was to evaluate the gene expression of ribonucleotide reductase large subunit 1 (RRM1) and excision repair cross-complementation group 1 (ERCC1) in ACC as potential biomarkers for clinical outcome and response to mitotane.

EXPERIMENTAL DESIGN

Forty-five and 47 tissue samples from two cohorts (Orbassano, Italy; Wuerzburg, Germany) of completely resected ACC were centrally analyzed using real-time PCR for RRM1 and ERCC1 expression. Fifty-four patients received surgery alone and 38 received adjuvant mitotane after surgery. Clinical and pathologic features were highly comparable in the two series. H295R and SW-13 ACC cell lines were also used for pharmacologic tests.

RESULTS

ERCC1 gene expression was not associated to clinical outcome. In contrast, high RRM1 gene expression was associated to shorter disease-free survival (DFS) and overall survival at both univariate and multivariate analysis. In patients with low RRM1 gene expression, adjuvant mitotane was associated with improved DFS, whereas this effect was lost in cases with high RMM1 expression. In vitro mitotane induced strong up regulation of RRM1 transcription (up to 25-fold increase) in mitotane-insensitive SW-13 but not in mitotane-sensitive H295R cells. Furthermore, RRM1 silencing in SW-13 cells induced sensitivity to mitotane.

CONCLUSION

Our in vitro and in vivo data indicate that RRM1 gene expression is functionally associated to mitotane sensitivity and support a possible role of RRM1 determination as a novel molecular biomarker predicting response to adjuvant mitotane in ACC.

The Weiss score and beyond--histopathology for adrenocortical carcinoma

The pathological diagnosis of adrenocortical carcinoma (ACC) is still challenging for its rarity and the presence of special variants (pediatric, oncocytic, myxoid, and sarcomatoid). It is based on the recognition at light microscopy of at least three among nine morphological parameters, according to the Weiss scoring system, which has been introduced 27 years ago and nowadays is the most widely employed. Nevertheless, the diagnostic performance of this system is very high but does not reach a sensitivity and specificity of 100%, its diagnostic applicability is potentially low among non-expert pathologists, and a group of borderline cases with only one or two criteria exist of uncertain behavior. Moreover, it is scarcely reproducible in the ACC morphological variants. In fact, specifically for the pure oncocytic neoplasms that seem to have a better prognosis in comparison to the conventional ACCs, a modified system (the Lin-Weiss-Bisceglia) has been proposed. With the aim to simplify the ACC diagnosis, 2 years ago, the "reticulin" diagnostic algorithm has been proposed, based on the observation that the tumoral reticulin framework (highlighted by reticulin silver-based histochemical staining) is consistently disrupted in malignant cases but only in a small subset of benign cases. Following this algorithm, in the presence of reticulin alterations, malignancy is further defined through the identification of at least one of the following parameters: necrosis, high mitotic rate, and venous invasion. As a complement to the morphological approach, some immunohistochemical markers (such as steroidogenic factor 1) have been proposed as diagnostic and prognostic adjuncts but still lack wide clinical validation.

Classification of parathyroid cancer

PURPOSE

Parathyroid cancer is rare and often has a poor outcome. There is no classification system that permits prediction of outcome in patients with parathyroid cancer. This study was designed to validate two prognostic classification systems developed by Talat and Schulte in 2010 ("Clinical Presentation, Staging and Long-term Evolution of Parathyroid Cancer," Ann Surg Oncol 2010;17:2156-74) derived from a retrospective literature review of 330 patients.

METHODS

This study contains 82 formerly unreported patients with parathyroid cancer. Death due to disease was the primary end point, and recurrence and disease-free survival were the secondary end points. Data acquisition used a questionnaire of predefined criteria. Low risk was defined by capsular and soft tissue invasion alone; high risk was defined by vascular or organ invasion, and/or lymph node or distant metastasis. A differentiated classification system further classified high-risk cancer into vascular invasion alone (class II), lymph node metastasis or organ invasion (class III), and distant metastasis (class IV). Statistical analyses included risk analysis, Kaplan-Meier analysis, and receiver-operating characteristic (ROC) analysis.

RESULTS

Follow-up ranged 2-347 months (mean 76 months). Mortality was exclusive to the high- risk group, which also predicted a significant risk of recurrence (risk ratio 9.6; 95% confidence interval 2.4-38.4; P < 0.0001), with significantly lower 5-year disease-free survival (χ(2) = 8.7; P < 0.005 for n = 45). The differentiated classification also provided a good prognostic model with an area under the ROC curve of 0.83 in ROC analysis, with significant impairment of survival between classes (98.6%, 79.2%, 71.4%, 40.0%, P < 0.05 between each class).

CONCLUSIONS

This study confirms the validity of both classification systems for disease outcome in patients with parathyroid cancer.

Adrenocortical neoplasia: evolving concepts in tumorigenesis with an emphasis on adrenal cortical carcinoma variants

Adrenocortical carcinoma (ACC) is a rare, heterogeneous malignancy with a poor prognosis. According to WHO classification 2004, ACC variants include oncocytic ACCs, myxoid ACCs and ACCs with sarcomatous areas. Herein, we provide a comprehensive review of these rare subtypes of adrenocortical malignancy and emphasize their clinicopathological features with the aim of elucidating aspects of diagnostic categorization, differential diagnostics and biological behavior. The issue of current terminology, applied to biphasic tumors with pleomorphic, sarcomatous or sarcomatoid elements arising in adrenal cortex, is also discussed. We additionally present emerging evidence concerning the adrenal cortical tumorigenesis and the putative adenoma-carcinoma sequence as well.

Contemporary management of adrenocortical carcinoma

CONTEXT

Adrenocortical carcinoma (ACC) is a rare and typically aggressive malignancy. Available recommendations are based primarily on retrospective series or expert opinions, and only few prospective clinical studies have yet been published.

OBJECTIVE

To combine the available evidence for diagnostic work-up and treatment of ACC to a contemporary recommendation on the management of this disease.

EVIDENCE ACQUISITION

We conducted a systematic literature search for studies conducted on humans and published in English using the Medline/PubMed database up to 31 January 2011. In addition, we screened published abstracts at meetings and several Web sites for recommendations on ACC management.

EVIDENCE SYNTHESIS

In patients with suspected localised ACC, a thorough endocrine and imaging work-up is followed by complete (R0) resection of the tumour by an expert surgeon. In experienced hands, laparoscopic adrenalectomy is probably as effective and safe for localised and noninvasive ACC as open surgery. Most clinicians agree that mitotane should be used as adjuvant therapy in the majority of patients, as they have a high risk for recurrence. An international panel has suggested using tumour stage, resection status, and the proliferation marker Ki67 as guidance for or against adjuvant therapy. In patients with advanced disease at presentation or recurrence not amenable to complete resection, a surgical approach is frequently inadequate. In these cases, mitotane alone or in combination with cytotoxic drugs is the treatment of choice. The most promising regimens (etoposide, doxorubicin, cisplatin plus mitotane, and streptozotocin plus mitotane) are currently compared in an international phase 3 trial, and results should be available by the end of 2011. Several targeted therapies are under investigation and may lead to new treatment options. Management of endocrine manifestations with steroidogenesis inhibitors is required in patients suffering uncontrolled hormone excess.

CONCLUSIONS

Detailed recommendations are provided to guide the management of patients with ACC.

Adrenocortical tumors with myxoid features: a distinct morphologic and phenotypical variant exhibiting malignant behavior

Myxoid changes have been rarely reported both in adrenocortical adenomas and carcinomas. The recent observation by our group of an adrenal myxoid tumor with morphologically borderline features, but aggressive clinical behavior prompted us to review a series of 196 adrenocortical lesions, comprising 122 carcinomas and 74 adenomas, to define the morphologic, phenotypical and clinical characteristics of adrenocortical tumors with myxoid features. Fourteen cases, including 12 carcinomas and 2 borderline tumors, formed the basis of this report, and were characterized by a variably abundant myxoid component (from 5% to 90% of tumor) and 2 distinct cellular growth patterns: the first (10 cases), mostly associated with a predominant myxoid stromal component, was made of small cells with mild atypia arranged in cords and microcysts; the second (4 cases) was characterized by focal myxoid changes in tumors otherwise similar to conventional adrenocortical carcinoma, with large atypical cells having an eosinophilic cytoplasm and a diffuse or nodular architecture. The above mentioned patterns were absent in all adenomas reviewed. A peculiar reactivity to neurofilaments was seen, mostly associated to the presence of predominant rather that focal myxoid stromal changes, and in 40% of conventional adrenocortical carcinomas, thus representing an undescribed potential pitfall in the differential diagnosis of adrenal lesions. Myxoid adrenocortical tumors probably represent a rare but histologically and phenotipically distinct entity and, although rare cases of benign lesions are on record, they seem to be generally associated to morphologic and clinical features of malignancy.