Diagnosis of Adrenocortical Tumors by Reticulin Algorithm

Limitation of the current Lin-Weiss-Bisceglia criteria in predicting poor prognosis in oncocytic adrenocortical neoplasms of uncertain malignant potential and oncocytoma diagnosed by the Lin-Weiss-Bisceglia criteria

Background

Oncocytic adrenocortical neoplasms (OANs) are extremely rare adrenal tumors whose diagnosis is challenging. This study aimed to identify risk factors for predicting poor prognosis in patients with OAN of uncertain malignant potential (OANUMP) and oncocytoma, OAN subtypes, and to evaluate the diagnostic utility of the current Lin-Weiss-Bisceglia (LWB) criteria.

Methods

We retrospectively reviewed 14 patients diagnosed with OANUMP or oncocytoma after adrenalectomy from February 2002 to May 2022. Patients re-classified as oncocytic adrenocortical carcinoma by the LWB criteria were excluded. We compared the clinicopathological and radiological features between patients with and without recurrence.

Results

Among the 14 patients, recurrence occurred in 3 (21%; 2 (67%) and 1 (33%) patients with OANUMP and oncocytoma, respectively). The proportion of patients with necrosis (66.7% vs 9.1%, p = 0.093), a Helsinki score >5 (66.7% vs 9.1%, p = 0.093), and malignancy by the reticulin algorithm (66.7% vs 9.1%, p = 0.093) were higher in the recurrence group than in the no-recurrence group but were not statistically significant. The percentages of patients with an indeterminate pathological resection margin (100% vs 63.6%, p = 0.192) tended to be higher in the recurrence group than in the no-recurrence group. Of the three patients with recurrence, two had tumor necrosis on the final pathology and were classified as malignant by the reticulin algorithm. One patient diagnosed as OANUMP by the LWB criteria had tumor necrosis and was classified as malignant by the reticulin algorithm and Helsinki scoring system.

Conclusion

Necrosis was associated with the recurrence of disease in patients with OANUMP according to the LWB criteria. The absence of necrosis as a major criterion in the current LWB criteria highlights its potential limitation in accurately assessing disease aggressiveness in OANs.

Diagnostic and prognostic assessments of adrenocortical carcinomas by pathological features, immunohistochemical markers and reticular histochemistry staining

BACKGROUND

Current diagnostic criteria of adrenocortical neoplasms are mostly based on morphology. The utility of immunohistochemistry (IHC) and histochemistry is limited.

MATERIALS AND METHODS

To evaluate the diagnostic and prognostic utility of clinicopathological features, morphology, ancillary biomarkers, and reticular histochemistry in adrenocortical neoplasms. We examined 28 adrenocortical carcinomas (ACCs) and 50 adrenocortical adenomas (ACAs) obtained from pathology archives. Clinical data were retrieved from medical records. Two pathologists independently assessed hematoxylin and eosin-stained slides, employing modified Weiss criteria for all tumors and Lin-Weiss-Bisceglia criteria for oncocytic variants. Immunohistochemical markers (Calretinin, alpha-inhibin, MelanA, SF-1, Ki-67, PHH3, IGF-2, β-catenin, P53, CYP11B1, CYP11B2, MLH1, MSH2, MSH6, PMS2, EPCAM) and Gomori's Silver histochemistry were applied. Statistical analysis utilized SPSS Statistics 26.

RESULTS

ACCs exhibited larger tumor sizes (P<0.001) and symptomatic presentations (P = 0.031) compared to ACAs. Parameters of modified Weiss criteria and angioinvasion demonstrated diagnostic value for ACCs. Six immunohistochemical antibodies((MelanA, Ki-67, IGF-2, β-catenin, P53 and CYP11B1) and reticulin framework alterations showed diagnostic value. Notably, Ki-67 and reticulin staining were most recommended. Evident reticulin staining was frequently present in ACCs (P<0.001). Ki-67 was significantly higher in ACCs (P<0.001). Twenty-one conventional and seven oncocytic entities showed different necrosis frequencies. Symptoms and Ki-67 index ≥ 30% were prognostic for ACCs, correlating with shorter survival.

CONCLUSIONS

This study emphasizes the diagnostic value of reticulin framework alterations and a high Ki-67 index. Markers such as CYP11B1, IGF2, P53, β-catenin and MelanA also contribute to the diagnosis of ACCs. Symptoms and Ki-67 index ≥ 30% predict shorter survival. These findings encourges the use of ancillary markers such as reticulin histochemistry and Ki-67 in the workup of evaluations of adrenocortical neoplasms.

Diagnostic Utility of a Modified Reticulin Algorithm in Pediatric Adrenocortical Neoplasms

Pediatric adrenocortical neoplasms (ACNs) are extremely rare tumors in contrast to their adult counterparts. Distinguishing benign from malignant is challenging based on pure morphologic grounds. Previously, 2 scoring systems were proposed in pediatric ACN, including the Wieneke criteria (WC) and its modified version (modified WC [mWC]). In adults, the reticulin algorithm (RA) has proven inexpensive, reliable, predictive, and reproducible; however, it has been validated only recently in children in a limited number of cases. This study aims to assess the RA utility compared with other scoring systems in a series of 92 pediatric ACNs. All cases were individually scored, and mitotic rate cutoffs were recorded. Reticulin alterations were classified as quantitative and qualitative. Outcome data were available in 59/92. The median age was 5 years (0.1 to 18 y) with an M:F of 0.6. Clinical presentation included virilization (39%), Cushing syndrome (21%), other symptoms (4%), and asymptomatic (36%). The reticulin framework was intact in 27% and altered in 73% of cases, showing qualitative (22%), quantitative (73%), and both (5%) alterations. In patients with favorable outcomes, 59% showed either intact reticulin or qualitative alteration compared with the unfavorable outcome group, where 90% showed quantitative alterations. All scoring systems WC ( P < 0.0001), mWC ( P = 0.0003), and the adult/pediatric RA ( P < 0.0001) had predictive value. The RA is comparable to WC and mWC, easier to apply, and is the most sensitive histopathological approach to identifying aggressive behavior in pediatric ACN. Its integration into the WC might be helpful in ACN of uncertain malignant potential and deserves further investigation.

Pediatric Adrenocortical Neoplasms: A Study Comparing Three Histopathological Scoring Systems

Adrenocortical neoplasms are rare in childhood. Their histopathological categorization into benign and malignant is often challenging, impacting further management. While the AFIP/Wieneke scoring system is widely used for the prognostic classification of these tumors, it has limitations. Few other tumor scoring systems have evolved over the past few years. These have been validated in adults but not yet in pediatric patients. We evaluated a cohort of pediatric adrenocortical neoplasms to assess the applicability of AFIP/Wieneke criteria and the recently introduced Helsinki score and reticulin algorithm in predicting clinical outcomes. A tumor was considered 'clinically aggressive' in the presence of any of the following: metastases, recurrence, progressive disease, or death due to disease. Cases without any such event were considered 'clinically good'. Event-free survival time was the duration from the date of clinical presentation to any post-operative adverse event. For overall survival analysis, the endpoint was either the last follow-up or death due to disease.Using ROC curve analysis, the obtained cut-off Helsinki score of 24 could stratify the cases into two prognostically relevant groups. Survival analysis showed significant differences in the event-free and overall survival of these two groups of patients, validating the proposed cut-off. None of the three histopathological scoring systems could predict an unfavorable outcome with 100% accuracy. All showed a sensitivity of ≥ 80%, with the reticulin algorithm achieving 100% sensitivity. The specificity and accuracy of the AFIP/Wieneke criteria were the lowest (62.5% and 73.08%, respectively). While the Helsinki score (at the cut-off score of 24) and the reticulin algorithm had similar accuracy rates (80.77%, and 80%, respectively), the specificity of the former was higher (81.25%) than the latter (68.75%). A separate analysis revealed that the Ki-67 index at a cut-off of 18% had a sensitivity of 80% and a specificity of 81.25% for predicting an unfavorable outcome.

Histopathologic Features of Adrenal Cortical Carcinoma

Adrenal cortical carcinoma (ACC) is a rare and aggressive malignancy that poses challenging issues regarding the diagnostic workup. Indeed, no presurgical technique or clinical parameters can reliably distinguish between adrenal cortical adenomas, which are more frequent and have a favorable outcome, and ACC, and the final diagnosis largely relies on histopathologic analysis of the surgical specimen. However, even the pathologic assessment of malignancy in an adrenal cortical lesion is not straightforward and requires a combined evaluation of multiple histopathologic features. Starting from the Weiss score, which was developed in 1984, several histopathologic scoring systems have been designed to tackle the difficulties of ACC diagnosis. Dealing with specific histopathologic variants (eg, Liss-Weiss-Bisceglia scoring system for oncocytic ACC) or patient characteristics (eg, Wieneke index in the pediatric setting), these scores remarkably improved the diagnostic workup of ACC and its subtypes. Nevertheless, cases with misleading features or discordant correlations between pathologic findings and clinical behavior still occur. Owing to multicentric collaborative studies integrating morphologic features with ancillary immunohistochemical markers and molecular analysis, ACC has eventually emerged as a multifaceted, heterogenous malignancy, and, while innovative and promising approaches are currently being tested, the future clinical management of patients with ACC will mainly rely on personalized medicine and target-therapy protocols. At the dawn of the new Fifth World Health Organization classification of endocrine tumors, this review will tackle ACC from the pathologist's perspective, thus focusing on the main available diagnostic, prognostic, and predictive tissue-tethered features and biomarkers and providing relevant clinical and molecular correlates.

Overview of the 2022 WHO Classification of Adrenal Cortical Tumors

The new WHO classification of adrenal cortical proliferations reflects translational advances in the fields of endocrine pathology, oncology and molecular biology. By adopting a question-answer framework, this review highlights advances in knowledge of histological features, ancillary studies, and associated genetic findings that increase the understanding of the adrenal cortex pathologies that are now reflected in the 2022 WHO classification. The pathological correlates of adrenal cortical proliferations include diffuse adrenal cortical hyperplasia, adrenal cortical nodular disease, adrenal cortical adenomas and adrenal cortical carcinomas. Understanding germline susceptibility and the clonal-neoplastic nature of individual adrenal cortical nodules in primary bilateral macronodular adrenal cortical disease, and recognition of the clonal-neoplastic nature of incidentally discovered non-functional subcentimeter benign adrenal cortical nodules has led to redefining the spectrum of adrenal cortical nodular disease. As a consequence, the most significant nomenclature change in the field of adrenal cortical pathology involves the refined classification of adrenal cortical nodular disease which now includes (a) sporadic nodular adrenocortical disease, (b) bilateral micronodular adrenal cortical disease, and (c) bilateral macronodular adrenal cortical disease (formerly known primary bilateral macronodular adrenal cortical hyperplasia). This group of clinicopathological entities are reflected in functional adrenal cortical pathologies. Aldosterone producing cortical lesions can be unifocal or multifocal, and may be bilateral with no imaging-detected nodule(s). Furthermore, not all grossly or radiologically identified adrenal cortical lesions may be the source of aldosterone excess. For this reason, the new WHO classification endorses the nomenclature of the HISTALDO classification which uses CYP11B2 immunohistochemistry to identify functional sites of aldosterone production to help predict the risk of bilateral disease in primary aldosteronism. Adrenal cortical carcinomas are subtyped based on their morphological features to include conventional, oncocytic, myxoid, and sarcomatoid subtypes. Although the classic histopathologic criteria for diagnosing adrenal cortical carcinomas have not changed, the 2022 WHO classification underscores the diagnostic and prognostic impact of angioinvasion (vascular invasion) in these tumors. Microscopic angioinvasion is defined as tumor cells invading through a vessel wall and forming a thrombus/fibrin-tumor complex or intravascular tumor cells admixed with platelet thrombus/fibrin. In addition to well-established Weiss and modified Weiss scoring systems, the new WHO classification also expands on the use of other multiparameter diagnostic algorithms (reticulin algorithm, Lin-Weiss-Bisceglia system, and Helsinki scoring system) to assist the workup of adrenal cortical neoplasms in adults. Accordingly, conventional carcinomas can be assessed using all multiparameter diagnostic schemes, whereas oncocytic neoplasms can be assessed using the Lin-Weiss-Bisceglia system, reticulin algorithm and Helsinki scoring system. Pediatric adrenal cortical neoplasms are assessed using the Wieneke system. Most adult adrenal cortical carcinomas show > 5 mitoses per 10 mm² and > 5% Ki67. The 2022 WHO classification places an emphasis on an accurate assessment of tumor proliferation rate using both the mitotic count (mitoses per 10 mm²) and Ki67 labeling index which play an essential role in the dynamic risk stratification of affected patients. Low grade carcinomas have mitotic rate of ≤ 20 mitoses per 10 mm², whereas high-grade carcinomas show > 20 mitoses per 10 mm². Ki67-based tumor grading has not been endorsed in the new WHO classification, since the proliferation indices are continuous variables rather than being static thresholds in tumor biology. This new WHO classification emphasizes the role of diagnostic and predictive biomarkers in the workup of adrenal cortical neoplasms. Confirmation of the adrenal cortical origin of a tumor remains a critical requirement when dealing with non-functional lesions in the adrenal gland which may be mistaken for a primary adrenal cortical neoplasm. While SF1 is the most reliable biomarker in the confirmation of adrenal cortical origin, paranuclear IGF2 expression is a useful biomarker in the distinction of malignancy in adrenal cortical neoplasms. In addition to adrenal myelolipoma, the new classification of adrenal cortical tumors has introduced new sections including adrenal ectopia, based on the potential role of such ectopic tissue as a possible source of neoplastic proliferations as well as a potential mimicker of metastatic disease. Adrenal cysts are also discussed in the new classification as they may simulate primary cystic adrenal neoplasms or even adrenal cortical carcinomas in the setting of an adrenal pseudocyst.

How to Differentiate Benign from Malignant Adrenocortical Tumors?

Simple Summary

Adrenocortical carcinoma is a rare cancer with a poor prognosis. Adrenal tumors are, however, commonly identified in clinical practice. Discrimination between benign and malignant adrenal tumors is of great importance to determine the appropriate treatment and follow-up strategy. This review summarizes the current diagnostic strategies and challenges to distinguish benign from malignant adrenal lesions. We will focus both on radiological and biochemical assessments, enabling diagnosis of the adrenal lesion preoperatively, and on histopathological and a wide variety of molecular assessments that can be done after surgical removal of the adrenal lesion. Furthermore, new non-invasive strategies such as liquid biopsies, in which blood samples are used to study circulating tumor cells, tumor DNA and microRNA, will be addressed in this review.

Abstract

Adrenocortical carcinoma (ACC) is a rare cancer with a poor prognosis. Adrenal incidentalomas are, however, commonly identified in clinical practice. Discrimination between benign and malignant adrenal tumors is of great importance considering the large differences in clinical behavior requiring different strategies. Diagnosis of ACC starts with a thorough physical examination, biochemical evaluation, and imaging. Computed tomography is the first-level imaging modality in adrenal tumors, with tumor size and Hounsfield units being important features for determining malignancy. New developments include the use of urine metabolomics, also enabling discrimination of ACC from adenomas preoperatively. Postoperatively, the Weiss score is used for diagnosis of ACC, consisting of nine histopathological criteria. Due to known limitations as interobserver variability and lack of accuracy in borderline cases, much effort has been put into new tools to diagnose ACC. Novel developments vary from immunohistochemical markers and pathological scores, to markers at the level of DNA, methylome, chromosome, or microRNA. Molecular studies have provided insights into the most promising and most frequent alterations in ACC. The use of liquid biopsies for diagnosis of ACC is studied, although in a small number of patients, requiring further investigation. In this review, current diagnostic modalities and challenges in ACC will be addressed.

The Role of Immunohistochemical Markers for the Diagnosis and Prognosis of Adrenocortical Neoplasms

Adrenal cortical carcinoma (ACC) is a rare cancer with poor prognosis that needs to be distinguished from adrenocortical adenomas (ACAs). Although, the recently developed transcriptome analysis seems to be a reliable tool for the differential diagnosis of adrenocortical neoplasms, it is not widely available in clinical practice. We aim to evaluate histological and immunohistochemical markers for the distinction of ACCs from ACAs along with assessing their prognostic role. Clinical data were retrospectively analyzed from 37 patients; 24 archived, formalin-fixed, and paraffin-embedded ACC samples underwent histochemical analysis of reticulin and immunohistochemical analysis of p27, p53, Ki-67 markers and were compared with 13 ACA samples. Weiss and Helsinki scores were also considered. Kaplan-Meier and univariate Cox regression methods were implemented to identify prognostic effects. Altered reticulin pattern, Ki-67% labelling index and overexpression of p53 protein were found to be useful histopathological markers for distinguishing ACAs from ACCs. Among the studied markers, only pathological p53 nuclear protein expression was found to reach statistically significant association with poor survival and development of metastases, although in a small series of patients. In conclusion, altered reticulin pattern and p53/Ki-67 expression are useful markers for distinguishing ACCs from ACAs. Immunohistopathology alone cannot discriminate ACCs with different prognosis and it should be combined with morphological criteria and transcriptome analysis.

Adrenocortical Carcinoma: Updates of Clinical and Pathological Features after Renewed World Health Organisation Classification and Pathology Staging

Adrenocortical carcinoma (ACC) is a heterogenous group of diseases with different clinical behaviour between adult and paediatric patients. In addition, three histological variants, oncocytic, myxoid and sarcomatoid are noted on the recent World Health Organisation (WHO) classification of ACC. A review of recent literature showed that the different types of ACC have distinctive demographic data, clinical presentation, pathology, biological behaviour, genomic and patients' prognosis. In addition, recent updates of pathology staging for ACC allow refinement of prognostic grouping for planning treatment of the patients with ACC. These advances in genomic, pathology and staging have driven the development of standardisation of pathology reporting. International standardisation of pathological reporting of adrenocortical carcinoma and adaption to local pathology communities provide universal platforms for clinicians and researchers involved in the management of patients with ACC. To conclude, all these advances in the field of pathology will improve development of management strategies including improvement of clinical care, development of prognostic markers and testing of novel therapeutic approaches for patients with adrenocortical carcinoma.

Reticulin staining pattern in the differential diagnosis of benign parathyroid lesions

AIM

A reticulin staining pattern (RSP) can be used for the differential diagnosis of endocrine gland lesions, as in the adrenal and hypophysis glands. We aimed to use RSP for the differential diagnosis of parathyroid gland lesions.

MATERIALS AND METHODS

In this study, we evaluated 97 parathyroid lesions in 85 patients, as well as 29 normal parathyroid glands. All sections were stained with a silver impregnation-based kit for the reticulin stain. The RSPs were classified as short thick fiber-, anastomosing- and nodular/alveolar-pattern. The dominant pattern was accepted as being greater than 50% in each section.

RESULTS

Short thick fibers and anastomosing and nodular RSPs were seen in adenomas, but there was no alveolar pattern. Although nodular/alveolar patterns were seen in focal areas in hyperplasia, they never became the dominant pattern. Nodular dominant RSPs were seen in adenomas; however, nodular RSPs were not seen in hyperplasia in a dominant pattern (p = 0.049). While short thick fibers were not seen in normal glands, they could be seen in adenomas (p < 0.001) and in hyperplasia (p < 0.001).

CONCLUSION

RSPs can be used in the differential diagnosis of parathyroid lesions. While short thick reticular fibers support adenomas and hyperplasia rather than normal tissue, a nodular dominant pattern supports adenomas rather than hyperplasia.

A Diagnostic Approach to Adrenocortical Tumors

Adrenocortical tumors range from primary bilateral micronodular or macronodular forms of adrenocortical disease to conventional adrenocortical adenomas and carcinomas. Accurate classification of these neoplasms is critical given the varied pathogenesis, clinical behavior, and outcome of these different lesions. Confirmation of adrenocortical origin, diagnosing malignancy, providing relevant prognostic information in adrenocortical carcinoma, and correlation of laboratory results with clinicopathologic findings are among the important responsibilities of pathologists who evaluate these lesions. This article focuses on a practical approach to the evaluation of adrenocortical tumors with an emphasis on clinical and imaging findings, morphologic characteristics, and multifactorial diagnostic schemes and algorithms.

Immunohistochemical Biomarkers of Adrenal Cortical Neoplasms

Careful morphological evaluation forms the basis of the workup of an adrenal cortical neoplasm. However, the adoption of immunohistochemical biomarkers has added tremendous value to enhance diagnostic accuracy. The authors provide a brief review of immunohistochemical biomarkers that have been used in the confirmation of adrenal cortical origin and in the detection of the source of functional adrenal cortical proliferations, as well as diagnostic, predictive, and prognostic biomarkers of adrenal cortical carcinoma. In addition, a brief section on potential novel theranostic biomarkers in the prediction of treatment response to mitotane and other relevant chemotherapeutic agents is also provided. In the era of precision and personalized medical practice, adoption of combined morphology and immunohistochemistry provides a new approach to the diagnostic workup of adrenal cortical neoplasms, reflecting the evolution of clinical responsibility of pathologists.