Immunocytochemical differential diagnosis of adrenocortical neoplasms using the monoclonal antibody D11

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.

Adrenal cortical tumors, pheochromocytomas and paragangliomas

Distinguishing adrenal cortical adenomas from carcinomas may be a difficult diagnostic problem. The criteria of Weiss are very useful because of their reliance on histologic features. From a practical perspective, the most useful criteria to separate adenomas from carcinomas include tumor size, presence of necrosis and mitotic activity including atypical mitoses. Adrenal cortical neoplasms in pediatric patients are more difficult to diagnose and to separate adenomas from carcinomas. The diagnosis of pediatric adrenal cortical carcinoma requires a higher tumor weight, larger tumor size and more mitoses compared with carcinomas in adults. Pheochromocytomas are chromaffin-derived tumors that develop in the adrenal gland. Paragangliomas are tumors arising from paraganglia that are distributed along the parasympathetic nerves and sympathetic chain. Positive staining for chromogranin and synaptophysin is present in the chief cells, whereas the sustentacular cells are positive for S100 protein. Hereditary conditions associated with pheochromocytomas include multiple endocrine neoplasia 2A and 2B, Von Hippel-Lindau disease and neurofibromatosis I. Hereditary paraganglioma syndromes with mutations of SDHB, SDHC and SDHD are associated with paragangliomas and some pheochromocytomas.

A tissue microarray-based comparative analysis of novel and traditional immunohistochemical markers in the distinction between adrenal cortical lesions and pheochromocytoma

We have encountered an increasing number of image-guided adrenal mass biopsies in which the differential diagnosis is adrenal cortical lesion versus pheochromocytoma. This distinction is sometimes difficult because of confounding clinical presentations, overlapping morphologies, and some degree of immunophenotypic overlap including focal staining with markers of purported lineage specificity. Interventional radiologists commonly use narrow gauge biopsy needles in this setting, which yield scant diagnostic tissue and further complicate pathologic evaluation. In this study, a detailed immunoprofile of 63 adrenal cortical lesions (3 adrenal rests, 6 adrenal cortical hyperplasias, 43 adrenal cortical adenomas, 4 adrenal cortical neoplasms of uncertain malignant potential, and 7 adrenal cortical carcinomas) was compared with 35 pheochromocytomas using traditional (calretinin, chromogranin, inhibin, melanA, and synaptophysin) and novel [steroidogenic factor-1 (SF-1), microtubule-associated protein 2, and mammalian achaete-scute homolog-1] antibodies, using tissue microarray technology to simulate small image-guided biopsies. Staining extent and intensity were each scored semiquantitatively for each antibody. A comparison of sensitivity and specificity using different intensity thresholds required for a "positive" result (> or = 1+ vs. > or = 2+) was performed. Staining results based on a > or = 1+ and (> or = 2+) intensity threshold were as follows: calretinin-95% (89%) in adrenal cortical lesions and 14% (0%) in pheochromocytomas; chromogranin-0% in adrenal cortical lesions and 100% in pheochromocytomas; inhibin-97% (86%) in adrenal cortical lesions and 6% (0%) in pheochromocytomas; microtubule-associated protein 2-29% (16%) in adrenal cortical lesions and 100% (89%) in pheochromocytomas; mammalian achaete-scute homolog-1-0% in both adrenal cortical lesions and pheochromocytomas; melanA-94% (86%) in adrenal cortical lesions and 6% (0%) in pheochromocytomas; SF-1-87% (86%) in adrenal cortical lesions and 0% in pheochromocytomas; synaptophysin-67% (59%) in adrenal cortical lesions and 100% in pheochromocytomas. Using an antibody panel consisting of chromogranin plus the nuclear antibody SF-1 and either calretinin or inhibin, while requiring a high-staining intensity threshold, helps to eliminate interpretative issues of artifactual or background reactivity, improves diagnostic sensitivity/specificity, and makes for an effective immunohistochemical approach in distinguishing adrenal cortical lesions from pheochromocytomas.

123I-Methyljodbenzylguanidin- (MIBG-) Szintigraphie

(123)I-metaiodobenzylguanidine (MIBG), a radio-labeled catecholamine analogue, is used for the imaging of pheochromocytoma based on the selective uptake of MIBG by chromaffin tissues. MIBG scintigraphy displays high sensitivity (90%) and specificity (close to 100%). In contrast, the false-positive uptake of MIBG by adrenal cortical carcinoma is rare. Here, we report a metastatic oncocytic adrenal cortical carcinoma with MIBG uptake used for therapeutic purposes.

Adrenocortical carcinoma

ACC is a rare clinical entity that carries a poor prognosis; early diagnosis and complete surgical resection are associated with the improvement in patient survival. Even with appropriated diagnosis and treatment, most patients will develop recurrence and succumb to ACC because of the underlying tumor biology, the difficulty of achieving a complete resection, and the lack of effective systemic therapies. Despite its many drawbacks, mitotane continues to be a mainstay in the treatment of high-risk patients with ACC, especially those with recurrent or metastatic disease. Recent findings suggest that mitotane, combined with conventional chemotherapeutic agents, may improve survival for such patients.

The clinically inapparent adrenal mass: update in diagnosis and management

Clinically inapparent adrenal masses are incidentally detected after imaging studies conducted for reasons other than the evaluation of the adrenal glands. They have frequently been referred to as adrenal incidentalomas. In preparation for a National Institutes of Health State-of-the-Science Conference on this topic, extensive literature research, including Medline, BIOSIS, and Embase between 1966 and July 2002, as well as references of published metaanalyses and selected review articles identified more than 5400 citations. Based on 699 articles that were retrieved for further examination, we provide a comprehensive update of the diagnostic and therapeutic approaches focusing on endocrine and radiological features as well as surgical options. In addition, we present recent developments in the discovery of tumor markers, endocrine testing for subclinical disease including autonomous glucocorticoid hypersecretion and silent pheochromocytoma, novel imaging techniques, and minimally invasive surgery. Based on the statements of the conference, the available literature, and ongoing studies, our aim is to provide practical recommendations for the management of this common entity and to highlight areas for future studies and research.

Adrenal cortical neoplasms in the pediatric population: a clinicopathologic and immunophenotypic analysis of 83 patients

Adrenal cortical neoplasms in pediatric patients (<20 years) are rare. The clinical manifestations and biologic behavior of these lesions can be quite distinct from their histologically similar counterparts in the adult population, making pathologic criteria for distinguishing benign from malignant tumors equivocal. We undertook a study of 83 adrenal cortical neoplasms to determine if adult clinical and histologic features can be applied to pediatric patients in an outcome-based analysis. Most of the patients (50 girls and 33 boys) presented with hormone-related symptoms present for a mean of 6.8 months. The tumors ranged in size from 2 to 20 cm (mean 8.8 cm). Histologic parameters examined included capsular and/or vascular invasion, extraadrenal soft tissue extension, growth pattern, cellularity, necrosis, cytoplasmic eosinophilia, nuclear pleomorphism, nuclear-to-cytoplasmic ratio, prominent nucleoli, mitotic figures, atypical mitotic figures, bands of fibrosis, and calcifications. Immunophenotypically, there was reactivity with inhibin, vimentin, CK5, and focally with p53 and Ki-67. All patients underwent adrenalectomy, and 20 patients received adjuvant therapy. All patients with tumors classified as adenomas (n = 9) were alive, without evidence of disease (mean 14.7 years), whereas 21 patients with carcinomas had died with disease (mean 2.4 years). Only 31% of histologically malignant tumors behaved in a clinically malignant fashion. Features associated with an increased probability of a malignant clinical behavior included tumor weight (>400 g), tumor size (>10.5 cm), vena cava invasion, capsular and/or vascular invasion, extension into periadrenal soft tissue, confluent necrosis, severe nuclear atypia, >15 mitotic figures/20 high power fields, and the presence of atypical mitotic figures. Vena cava invasion, necrosis, and increased mitotic activity (>15 mitotic figures/20 high power fields) independently suggest malignant clinical behavior in multivariate analysis.

High diagnostic accuracy of adrenal core biopsy: results of the German and Austrian adrenal network multicenter trial in 220 consecutive patients

Incidentally detected adrenal tumors are a common finding during abdominal ultrasonography, computed tomography, and magnetic resonance imaging. Although most of these lesions are benign adenomas, adrenocortical carcinomas and metastases constitute 5% to 10% of all tumors. Adrenal biopsy may be helpful, but its diagnostic value is controversial and disputed, and prospective studies have not yet been performed. Therefore, the diagnostic accuracy of adrenal core biopsy was evaluated in a prospective multicenter study involving 8 surgical centers in Germany and Austria. A total of 220 biopsies from surgical specimens of the adrenal gland were punctured in an ex vivo approach and processed for pathohistologic diagnosis using paraffin sections, routine staining, and immunohistochemistry (keratin KL1, vimentin, S100 protein, chromogranin A, synaptophysin, neuron-specific enolase, D11, MiB-1, and p53 protein). The evaluating pathologist was blinded for clinical data from the patients. A total of 89 adrenal adenomas (40.5%), 22 adrenal carcinomas (10.0%), 55 pheochromocytomas (25.0%), 15 metastases (6.8%), 16 adrenal hyperplasias (7.2%), and 23 other tumors (10.5%) were studied. Nine cases were excluded due to incomplete data (n = 2) or insufficient biopsy specimen (n = 7). In the remaining 211 tumors, compared with the final diagnoses of the surgical specimen, bioptic diagnoses were absolutely correct in 76.8% of the cases, nearly correct in 13.2% of the cases, and incorrect in 10% of the cases. Pheochromocytomas were correctly diagnosed in 96% of the cases, cortical adenomas were correctly or nearly correctly reported in 91% of the cases, cortical carcinomas were correctly or nearly correctly reported in 76% of the cases, and metastases were correctly or nearly correctly reported in 77% of the cases. Of the 39 malignant lesions, only 4 were misclassified, 2 as benign and 2 as possibly malignant. This resulted in an overall sensitivity for malignancy of 94.6% and specificity of 95.3%. Our findings suggest that adrenal core biopsy is a useful method for identifying and classifying adrenal tumorous lesions if sufficient biopsy specimens can be obtained. However, in clinical practice it remains to be shown whether the benefits of biopsy outweigh the risks of the procedure.

Histopathological classification of adrenal tumours

Tumours in the adrenals originate from the adrenal cortex, the adrenal medulla or as metastases from extra-adrenal primaries. Differentiating between these three groups is the first task a pathologist has to tackle when dealing with specimens from the adrenal region. Whereas this is possible in every case with total removal of the adrenal tumour it may be impossible in fine needle biopsies of such tumours. The second great problem is the dignity of adrenal tumours, which cannot be determined in many adrenomedullary and some adrenocortical tumours. Immunostainings are helpful but the basic method remains the histopathological examination of paraffin sections. This review gives an update of pathological findings in several adrenal tumour entities, and provides guidelines for the diagnosis of these tumours in the light of recently published data.

Diagnostic utility of the monoclonal antibody A103 in fine-needle aspiration biopsies of the adrenal

Fine-needle aspiration (FNA) of the adrenal is a useful modality for the evaluation of primary and metastatic neoplasms. Until now, however, few reliable markers existed for the positive identification of adrenal cortical cells. Originally studied as a melanoma marker, Melan-A, as detected by the murine monoclonal antibody, A103, has gained recent attention as a marker for steroid-producing cells. Formalin-fixed, paraffin-embedded cell blocks from 24 adrenal FNA specimens were stained for cytokeratins (AE1/AE3) and Melan-A (A103). Seven of 8 cases containing normal, hyperplastic, and neoplastic adrenal cortical cells were positive for A103. Among 16 cases of metastatic carcinoma, tumor cells in 14 samples were positive for cytokeratins but negative for A103. The A103 monoclonal antibody is a sensitive marker for the identification of normal, hyperplastic, and neoplastic adrenal cortical cells in cell blocks of adrenal FNA specimens. With the exception of melanoma, A103 reactivity is restricted to adrenal cortical and other steroid-producing cells. A103 should be used routinely for the evaluation of FNA specimens of adrenal mass lesions.

Fat-Cell Metaplasia in the Adrenal Cortex: Incidence, Structure, and Correlation to Basic Diseases in a Postmortem Series

In a postmortem series of adrenals from 497 patients 25 cases (5%) showed foci of fat-cell metaplasia or bone-marrow metaplasia in the zona fasciculata or the zona reticularis. There was only one focus in 45% of adrenals with metaplasia, but in 36.4%. more than six foci were present. The sizes varied between 0.036 and 0.64 mm. The foci were composed of mature, mostly univacuolar, fat cells and various amounts of myeloid cells The incidence of fat-cell metaplasia or of bone marrow metaplasia correlated with arterial hypertension and severe coronary heart disease. In 76% of cases, nodular hyperplasia was demonstrable, but the metaplasia were more often found adjacent to, rather than within, the nodules. They appear to be related to metaplasia in adrenocortical tumors and to myelolipomas. The common pathogenesis is thought to be based on focal necroses in combination with local endocrine stimulation.

Immunoreactivity for A103, an antibody to melan-A (Mart-1), in adrenocortical and other steroid tumors

The Melan-A (MART-1) gene encodes an antigen recognized by cytotoxic T cells. It has been said to be restricted in its expression to melanocytes. However, here we report the presence of immunoreactivity for A103, an antibody to Melan-A, in five adrenocortical adenomas, 16 primary and 13 metastatic adrenocortical carcinomas, four Leydig cell tumors of the testis, and three Sertoli-Leydig cell tumors of the ovary. To evaluate the potential diagnostic role of this antibody, we studied immunoreactivity for A103 in 111 carcinomas, 40 germ cell tumors, and 33 miscellaneous nonmelanocytic epithelioid tumors. All of them were negative for A103. Our findings suggest that once melanoma is excluded, A103 can aid in the recognition of steroid hormone-producing tumors and may be particularly useful in the diagnosis of adrenocortical carcinoma. The presence of immunoreactivity for A103 practically excludes any other carcinoma that may enter into the differential diagnosis of adrenocortical tumors.

Hyperplastic and Tumorous Lesions of the Adrenals in an Unselected Autopsy Series

In an unselected consecutive postmortem series, 512% of the adrenals showed cortical nodules with diameters up to 1 mm in 13%, between 1 and 2 mm in 28% and < 2 mm in 12%. In 22% of cases only one nodule was present; whereas in 15% two nodules and in 17% more than three nodules were found. A cortical adenoma was detected in 5% of cases. Adenomas were smaller than 6 mm in 1% and < 15 mm also in 1% of the entire collection. For differentiation of nodules criteria listed in Table 4 were used. Correlation with clinical data revealed a significantly higher number of nodules and an adenoma more frequently in hypertensive patients. Metastases were found in 19% of all cases with malignant tumors. Twenty-three percent of the metastases were smaller than 1 mm and 20% were < 10 mm in diameter. Adrenal metastases usually indicated generalized dissemination of the tumor.

Contralateral adrenal metastasis in renal cell cancer

A 60-year-old female patient presenting with anemia was found to have a left-sided renal tumor and a contralateral adrenal mass of 2 cm in diameter. Imaging studies for metastases were negative. Nephrectomy along with contralateral adrenalectomy was performed and histology disclosed renal cell carcinoma stage pT3a pNO G2 with solitary contralateral adrenal metastasis. In a survey of the literature, 24 previous cases of renal cancer with solitary contralateral adrenal metastasis were identified. The most probable biological pathway to explain this peculiar metastatic pattern is transpulmonal passage of circulating cancer cells and seeding in the adrenal gland on the basis of a particular susceptibility of adrenal tissue to circulating renal cancer cells. The case illustrates that surgery of solitary metastases from renal cell carcinoma may be beneficial to the patient. The case further highlights the caution that is required diagnostically in the interpretation of incidentally found adrenal masses when other malignancies are present.

Monoclonal Antibodies Recognizing Normal and Neoplastic Human Adrenal Cortex

Four monoclonal antibodies (MAb) were generated by immunization of mice with dispersed cells from normal human adrenal gland (Na) and adrenocortical adenoma causing cortisol excess (Ac). Immunohistochemically reacted cryosections revealed differential labeling of the normal cortical parenchyma, and immunofluorescence on dispersed cells displayed that Ac5 alone labeled the cell surface. Immunoprecipitation demonstrated that the antibodies recognized apparently different structures of 51-88 kDa. Immunohistochemical examination of several normal human tissues substantiated restricted reactivity, especially for the Na2 and Na7 antibodies, and that the adrenal medulla was not stained by any of the antibodies. The antibodies recognized the vast majority of the parenchymal cells of cortical adenomas (n = 21). Each antibody also reacted with all adrenocortical carcinomas (n = 17), and the staining generally was most intense and extensive with Na7. Analysis of other pathological human tissues revealed highly restricted reactivity for the Na2 antibody. Na2 and Na5 failed to stain 17 renal cell carcinomas. None of the antibodies recognized pheochromocytomas. These antibodies may lead to improved histological recognition and characterization of human adrenal lesions.

Immunohistochemical study of adrenocortical carcinoma. Predictive value of the D11 monoclonal antibody

BACKGROUND

The diagnosis of adrenocortical carcinoma (ACC) may be difficult with conventional light microscopy, especially when the tumor is nonfunctioning. Until now, no specific adrenocortical tumor marker was available. The current study was undertaken to investigate the interest of the D11 MoAb for the diagnosis and prognosis of ACC.

METHODS

Eighteen adrenocortical carcinomas, 10 primary adrenomedullary tumors, 20 primary hepatocellular carcinomas, 50 primary renal cell carcinomas, 5 primary lung carcinomas, and 18 intraadrenal metastases were analyzed immunohistochemically with the D11 monoclonal antibody. ACC were also evaluated for the expression of other tumor markers, including neuron-specific enolase, chromogranin A, S-100, Leu-7, vimentin, KL1, AE1AE3, and epithelial membrane antigen. Relationships between clinical features and results of immunohistochemistry were also sought.

RESULTS

Nuclear D11 staining appears to be highly specific for normal adrenocortical cells and related tumors. Nuclear D11 positivity was demonstrated in 44% of ACC and was restricted to well-differentiated tumors. No cytoplasmic or nuclear D11 staining was observed in adrenomedullary tumors. D11 reactivity confined to the cytoplasm was found in 5 of 18 adrenal metastases, in all 20 hepatocellular carcinomas tested, in 3 of 5 lung carcinomas, and in 1 of 50 primary renal cell carcinomas. Patients with nuclear D11 immunostaining were initially seen with metastases less often and survived longer than those with no nuclear D11 immunostaining (P < 0.05).

CONCLUSIONS

Nuclear D11 immunoreactivity may help to differentiate ACC from intraadrenal metastases and adrenomedullary tumors. This also selects a group of ACC patients with a more favorable outcome.

Immunohistological studies for gastrointestinal and other hormones in acth-secreting adenomas

Eighty-nine ACTH-secreting pituitary adenomas from patients with Cushing's disease or Nelson's syndrome were investigated by immunohistochemical methods for their content of gastrin, cholecystokinin (CCK), vasoactive intestinal peptide (VIP), bombesin, substance P, and ubiquitin as a marker for intercellular fibrils and hyalin and D11 as a marker for adrenocortical tissue. In contrast to in vitro studies reported in the relevant literature, we did not find significantly positive percentages (more than 10% of adenoma cells) for gastrin and CCK. VIP and bombesin were demonstrated in one adenoma. Among the adenomas examined, ubiquitin was found in 15% and D11 in 75%. ACTH was present in 99%, pro-γ-MSH in 21 %, β-endorphin in 13%, enkephalin in 4%, and α-subunit in 11.5%. The significance of the findings is discussed.

Immunocytochemistry in adrenocortical tumours: a clinicomorphological study of 72 neoplasms

Surgical specimens of 72 adrenocortical tumours (ACTs) were investigated. Histologically, 57 tumours were classified as adenomas and 15 as carcinomas. In 9 of the latter cases, distant metastases and/or lethal outcome of disease was recorded. Immunocyto-chemistry showed only 2 ACTs to be positive for cytokeratin and 6 for vimentin. None of the 72 tumours showed argyrophilia or immunoreactivity for epithelial membrane antigen (EMA), S-100 protein, chromogranin A, Leu 7 or Leu-M1, while 31 cases exhibited positivity on immunostaining with a polyclonal antiserum against synaptophysin. All 72 ACTs were immunoreactive with the recently described antibody D11. Thus the panel of antibodies described here could not discriminate between adenomas and carcinomas or between carcinomas with aggressive and indolent behaviour. Immunostaining with D11 and for EMA and Leu-M1 may help to distinguish ACTs from phenotypically similar lesions of different histogenesis.

Detection of tumor antigens with monoclonal antibodies: immunopathology and immunodiagnosis

The immunocytochemical demonstration, using monoclonal antibodies, of diverse cellular constituents has improved our understanding of many aspects of oncology. This review will focus on this approach to facilitate the detection of human tumors, improve their histological classification and provide functional parameters with potential aetiological, prognostic and/or therapeutic value.