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.     

Keratin Expression in Endocrine Organs and their Neoplasms

Keratins are intermediate filaments that provide mechanical support and fulfill a variety of additional functions in epithelial cells. Keratins show outstanding degree of molecular diversity. In humans, 54 functional keratin genes exist. Twenty common types of keratins are expressed in highly specific patterns related to epithelial type and stage of cellular differentiation. In general, keratins are classified as high-molecular-weight keratins (expressed in normal stratified epithelium and tumors derived from it) and low-molecular-weight keratins (expressed in normal simple epithelium and tumors derived from it). Histologically, endocrine organs belong to simple epithelium; thus, endocrine tissues usually express low-molecular-weight keratins. When an endocrine organ undergoes malignant transformation, its keratin profile usually remains constant. However, keratin expression in endocrine organs and endocrine tumors is much more complicated because of their diversified histogenesis. In this review article, we will first briefly review the molecular biology and protein chemistry of the keratins. We will then review the expression patterns of keratins in normal endocrine tissue and endocrine neoplasms.     

Immunohistochemical Biomarkers of Gastrointestinal,Pancreatic, Pulmonary,and Thymic Neuroendocrine Neoplasms

Neuroendocrine neoplasms (NENs) are a heterogeneous group of epithelial neoplastic proliferations that irrespective of their primary site share features of neural and endocrine differentiation including the presence of secretory granules, synaptic-like vesicles, and the ability to produce amine and/or peptide hormones. NENs encompass a wide spectrum of neoplasms ranging from well-differentiated indolent tumors to highly aggressive poorly differentiated neuroendocrine carcinomas. Most cases arise in the digestive system and in thoracic organs, i.e., the lung and thymus. A correct diagnostic approach is crucial for the management of patients with both digestive and thoracic NENs, because their high clinical and biological heterogeneity is related to their prognosis and response to therapy. In this context, immunohistochemistry represents an indispensable diagnostic tool that pathologists need to use for the correct diagnosis and classification of such neoplasms. In addition, immunohistochemistry is also useful in identifying prognostic and theranostic markers. In the present article, the authors will review the role of immunohistochemistry in the routine workup of digestive and thoracic NENs.     

Salivary Biomarkers: Toward Future Clinical and Diagnostic Utilities

SUMMARY

The pursuit of timely, cost-effective, accurate, and noninvasive diagnostic methodologies is an endeavor of urgency among clinicians and scientists alike. Detecting pathologies at their earliest stages can significantly affect patient discomfort, prognosis, therapeutic intervention, survival rates, and recurrence. Diagnosis and monitoring often require painful invasive procedures such as biopsies and repeated blood draws, adding undue stress to an already unpleasant experience. The discovery of saliva-based microbial, immunologic, and molecular biomarkers offers unique opportunities to bypass these measures by utilizing oral fluids to evaluate the condition of both healthy and diseased individuals. Here we discuss saliva and its significance as a source of indicators for local, systemic, and infectious disorders. We highlight contemporary innovations and explore recent discoveries that deem saliva a mediator of the body''s physiological condition. Additionally, we examine the current state of salivary diagnostics and its associated technologies, future aspirations, and potential as the preferred route of disease detection, monitoring, and prognosis.     

Carcinoma Arising in Microglandular Adenosis: An Immunohistochemical Analysis of 20 Intraepithelial and Invasive Neoplasms

Microglandular adenosis (MGA) of the breast is an uncommon, benign lesion that may mimic invasive carcinoma and has recently been recognized as having significant premalignant potential. When carcinomas arise in MGA, there is often a transition from ordinary MGA to atypical MGA (AMGA) to carcinoma. Nineteen cases of carcinoma arising in MGA are reported: 7 invasive carcinomas, 7 intraductal carcinomas (DCIS), and 5 with both invasive and intraductal carcinoma. A single case of AMGA without carcinoma is also reported. The 20 patients ranged in age from 36 to 81 years (mean 52). The most common clinical presentation was either a palpable mass (13 patients) or a mammographic abnormality (4 patients). All 20 cases contained AMGA, and in some cases AMGA was the predominant lesion. In 18 of the 19 cases with carcinoma, there was a clear transition from AMGA to the carcinoma. Twelve cases contained ordinary MGA, but in only 2 cases was MGA a prominent component of the lesion. In contrast to ordinary MGA, the glands of AMGA were more irregularly shaped, closely packed, and cytologically atypical and tended to lack secretions. A solid, occlusive proliferation of cells in the tubules was seen in 10 cases. All 12 examples of in situ carcinoma were either grade 2 or 3 and typically showed a solid proliferation of severely atypical cells within the glands; a cribrifrom pattern was also present in 1 case. The invasive carcinomas were morphologically diverse and included 2 with a basaloid morphology and 2 metaplastic carcinomas. Various immunostains were performed, and each lesion (AMGA, in situ, and invasive carcinoma) was separately assessed for immunoreactivity. As expected, S-100 was positive in the vast majority of AMGA and in situ carcinomas and in all 12 invasive carcinomas. S-100beta was also positive in the majority of cases although the staining was weaker. Laminin and type IV collagen highlighted the basement membrane around the AMGA and in situ carcinoma and are useful stains in difficult cases. Except for a single case, ER and PR were negative in all lesions. Cytokeratin 7 (CK 7) was positive, while cytokeratin 20 (CK 20) was negative in all cases. Immunostains for CK903 showed no reactivity in any of the invasive carcinomas, in situ carcinomas, or atypical MGA but was focally present in the associated MGA in 2 of the 8 cases studied. Immunostains for MIB-1 and p53 were semiquantitatively assessed and both were positive in AMGA but tended to show a more intense staining in the carcinomas. Five cases were also studied for immunoexpression of alpha-1 antitrypsin (AAT), alpha-1 antichymotrypsin (ACTP), lysozyme, and salivary gland amylase. All 5 invasive carcinomas were positive for ACTP, though the staining was very focal in about 10% of the cells in a basaloid carcinoma. The in situ carcinoma as well as the AMGA in 4 of the 5 cases were positive for ACTP. Three of the 5 invasive carcinomas were positive for AAT in 10% to 40% of the cells. The most intense positivity for AAT and ACTP was in cells with coarsely granular apocrine appearance evident in 2 of the 5 cases. Four of the 5 invasive carcinomas were positive for lysozyme in 10% to 50% of the cancer cells; the in situ carcinoma and the associated AMGA showed similar immunoreaction in each case. None of the 5 cases showed convincing positivity for salivary gland amylase. The MGA in all 5 cases was negative for AAT and ACTP; the MGA in 1 of the 5 cases was positive for lysozyme. This study confirms the potential of MGA to develop into an invasive carcinoma, more clearly defines the features of AMGA, highlights the importance of AMGA in the evolution of carcinoma from MGA, and expands our knowledge of the immunophenotype of AMGA and the carcinomas arising from it. The diagnostic criteria briefly noted previously for diagnosis of AMGA and carcinoma arising in MGA are expanded and formally proposed. Int J Surg Pathol 8(4):303-315, 2000     

Immunohistochemical Localization of p53 in Human Thyroid Neoplasms: Correlation with Biological Behavior

Molecular analyses of thyroid tumors have documented mutations in the tumor suppressor p53 gene almost exclusively in anaplastic carcinomas. In contrast, immunohistochemistry has localized p53 in differentiated papillary and follicular thyroid cancers. To establish the significance of p53 immunolocalization in these lesions, 78 thyroid tumors of follicular derivation were examined. All tumors were classified by strict criteria and the extent of tumor was determined morphologically. Immunohistochemical staining for p53 was performed on paraffin sections of formalin-fixed tumor tissue. The results of staining were correlated with diagnosis, tumor extent and clinical outcome. Immunopositivity for p53 was diffuse and strong in all five anaplastic carcinomas examined. There was no staining in five of six follicular adenomas. Four of nine follicular carcinomas had some degree of nuclear staining, but this was focal; all nine tumors were confined to the thyroid at the time of examination. Of 49 papillary carcinomas, 26 were intrathyroidal, and 7 of these were occult; there was no p53 positivity in any occult lesion and only 5 of the 19 palpable lesions stained. In contrast, among 23 papillary carcinomas with extrathyroidal extension or metastases, only 9 were negative for p53 immunoreactivity. Five of seven tall cell papillary carcinomas and one of two insular carcinomas had p53 immunopositivity and this correlated with aggressive behavior. These results support the tumorigenic role of p53 mutations postulated for anaplastic thyroid carcinomas and indicate that localization of p53 by immunohistochemistry is a useful prognostic index of clinical behavior in differentiated thyroid carcinomas of follicular cell derivation.     

The Diagnostic Significance of Intracytoplasmic Lumina in Metastatic Neoplasms

The diagnostic significance of intracytoplasmic lumina (ICL) was evaluated in a series of 61 consecutive and unselected metastatic neoplasms in lymph nodes, soft tissues, and bone studied by light and electron microscopy. Their only common denominator was a light microscopic diagnosis of “metastatic tumor of unknown primary site.”

With only rare exceptions, all previous reports of ICL on neoplastic cells deal with glandular organs or organs in which a glandular “metaplasia” may occur. Since primary or metastatic lesions of poorly differentiated squamous carcinomas, melanomas, and lymphomas may often cause problems in the differential diagnosis of poorly differentiated metastases, we also studied a large series of these neoplasms to see if they exhibited ICL.

Our study shows that when ICL are present in a metastatic carcinoma of undetermined primary site, the breast is the most likely site of the primary tumor, but that the clinical context may, and often does, modify the validity of this criterion. Our demonstration of ICL in two adnexal carcinomas of sweat and meibomian glands should discourage pathologists from jumping to a conclusion of a metastatic breast carcinoma whenever ICL are found in a tumor in the skin.

The presence of ICL seems to rule out the possibility of the neoplasm being a squamous carcinoma, a lymphoma, or a malignant melanoma.

Histochemical techniques were useful in diagnosing cases of mesotheliomas and adenomatoid tumors in which ICL are positive with Alcian blue but become negative after hyaluronidase digestion. The notion that mucicarmine positivity might exclude breast carcinoma was not confirmed in our study.     

The Diagnostic Significance of Intracytoplasmic Lumina in Metastatic Neoplasms

The diagnostic significance of intracytoplasmic lumina (ICL) was evaluated in a series of 61 consecutive and unselected metastatic neoplasms in lymph nodes, soft tissues, and bone studied by light and electron microscopy. Their only common denominator was a light microscopic diagnosis of “metastatic tumor of unknown primary site.”

With only rare exceptions, all previous reports of ICL on neoplastic cells deal with glandular organs or organs in which a glandular “metaplasia” may occur. Since primary or metastatic lesions of poorly differentiated squamous carcinomas, melanomas, and lymphomas may often cause problems in the differential diagnosis of poorly differentiated metastases, we also studied a large series of these neoplasms to see if they exhibited ICL.

Our study shows that when ICL are present in a metastatic carcinoma of undetermined primary site, the breast is the most likely site of the primary tumor, but that the clinical context may, and often does, modify the validity of this criterion. Our demonstration of ICL in two adnexal carcinomas of sweat and meibomian glands should discourage pathologists from jumping to a conclusion of a metastatic breast carcinoma whenever ICL are found in a tumor in the skin.

The presence of ICL seems to rule out the possibility of the neoplasm being a squamous carcinoma, a lymphoma, or a malignant melanoma.

Histochemical techniques were useful in diagnosing cases of mesotheliomas and adenomatoid tumors in which ICL are positive with Alcian blue but become negative after hyaluronidase digestion. The notion that mucicarmine positivity might exclude breast carcinoma was not confirmed in our study.     

胰岛素样生长因子—Ⅰ在胎儿肝，肾等组织的分布

目的 研究胰岛素样生长因子（IGFs）对胎儿组织增殖和分化的作用。方法 应用免疫组化ABC法对16至24周胎龄肝、肾、肾上腺、脾、胸腺等ICF－I阳性细胞进行定位研究。结果 胎儿期内,以上器官中均有IGF－I阳性细胞存在,不同个体和器官其阳性细胞的数量、反应强弱和表达情况有差异。结论 在人胎发育过程中,这些器官组织均能表达IGF－I,对其增殖分化起着自分泌和旁分泌的作用。     

Complex Endocrinopathies in MEN-1: Diagnostic Dilemmas in Endocrine Oncology

Endocrine oncology is a complex area that must determine the site of a neoplastic process and the hormonal dysregulation that ensues. Patients with endocrine tumors often have delayed diagnosis because of the nonspecific and often subtle signs and symptoms. In patients with multiple endocrine neoplasia syndromes, diagnosis and clinicopathologic correlations can be even more challenging. We report a patient with multiple endocrine neoplasia type 1 (MEN-1) and a highly complex clinical story associated with multiple atypical lesions including two pituitary adenomas, a gonadotroph macroadenoma and a corticotroph microadenoma with Crooke's hyaline change and ectopic production of corticotropin-releasing hormone (CRH) from a thymic endocrine carcinoma. These lesions resulted in a highly complex clinical story, difficult diagnoses and questions about management. This case illustrates a number of clinically relevant challenges, including the diagnosis of pituitary adenomas in MEN-1, the difficulty in diagnosing Cushing's disease, and the large differential of pituitary pathologies in this disorder, double pituitary adenomas and other decoy lesions in Cushing's disease, the pathophysiology of Crooke's hyaline change in the pituitary, and the various causes of Cushing's syndrome associated with MEN-1.     

Systems Biology and the Discovery of Diagnostic Biomarkers

Systems biology is an approach to the science that views biology as an information science, studies biological systems as a whole and their interactions with the environment. This approach, for the reasons described here, has particular power in the search for informative diagnostic biomarkers of diseases because it focuses on the fundamental causes and keys on the identification and understanding of disease- perturbed molecular networks. In this review, we describe some recent developments that have used systems biology to address complex diseases – prion disease and drug induced liver injury- and use these as examples to illustrate the importance of understanding network structure and dynamics. The knowledge of network dynamics through in vitro experimental perturbation and modeling allows us to determine the state of the networks, to identify molecular correlates, and to derive new disease treatment approaches to reverse the pathology or prevent its progress into a more severe state through the manipulation of network states. This general approach, including diagnostics and therapeutics, is becoming known as systems medicine.     

Unusual Endocervical Polypoid Tumor with Endocrine Cells: An Immunohistochemical and Ultrastructural Analysis

Light microscopic, immunohistochemical, and ultra-structural features of an unusual polypoid tumor of endocervix are reported. Numerous polypeptide hormone and amine-producing endocrine cells were disclosed. Main conventional characteristics were the architectural growth pattern, with infolding glands giving rise to small secondary glands, the hypermucinous benign-appearing epithelium of endocervical type, and, possibly, the stromal smooth muscle. Ultrastructural analysis showed a highly differentiated tumor. Glandular elements were surrounded by a basal lamina. Mucinous cells, several endocrine cell types, amphicrine cells, nonsecretory ciliated cells, ciliated mucinous cells, and possible reserve cells were observed. This tumor departs appreciably from normal mucosa and common varieties of endocervical polyp, particularly its distinctive endocrine profile. The present case does not correspond to a well-defined type of endocervical neoplasia. It shares morphologic analogies with mucinous tumor of ovary. The malignant potential of this lesion as well as its relationship with minimal deviation adenocarcinoma remain questionable.     

Unusual Endocervical Polypoid Tumor with Endocrine Cells: An Immunohistochemical and Ultrastructural Analysis

Light microscopic, immunohistochemical, and ultra-structural features of an unusual polypoid tumor of endocervix are reported. Numerous polypeptide hormone and amine-producing endocrine cells were disclosed. Main conventional characteristics were the architectural growth pattern, with infolding glands giving rise to small secondary glands, the hypermucinous benign-appearing epithelium of endocervical type, and, possibly, the stromal smooth muscle. Ultrastructural analysis showed a highly differentiated tumor. Glandular elements were surrounded by a basal lamina. Mucinous cells, several endocrine cell types, amphicrine cells, nonsecretory ciliated cells, ciliated mucinous cells, and possible reserve cells were observed. This tumor departs appreciably from normal mucosa and common varieties of endocervical polyp, particularly its distinctive endocrine profile. The present case does not correspond to a well-defined type of endocervical neoplasia. It shares morphologic analogies with mucinous tumor of ovary. The malignant potential of this lesion as well as its relationship with minimal deviation adenocarcinoma remain questionable.     

Immunohistochemical and Ultrastructural Analysis of Bronchopulmonary Neuroendocrine Neoplasms. I. Carcinoids

Twenty-five strictly defined bronchopulmonary carcinoids were studied by light microscopic immunohistochemistry by the peroxidase technique for NSE (neuronspecific enolase), serotonin, and a broad spectrum of neuropeptides. Eighteen cases were also studied by electron microscopy.

Twenty-three of the twenty-five cases showed immunostaining for NSE; 24 cases displayed immuno-staining for at least two of the hormones tested for; the single case that failed to show hormonal immuno-reactivity was however positive for NSE and had granules by electron microscopy. Serotonin was the most frequently demonstrated hormone followed by bombesin, vasoactive intestinal peptide, gastrin, leuenkephalin, alphamelanocyte stimulating hormone, somatostatin, substance P, and calcitonin. In several cases, adjacent-step sections stained for different hormones strongly indicated immunoreactivity for more than one hormone in single neoplastic cells.

By electron microscopy, all 18 cases studied showed generally abundant neurosecretory granules, which, however, displayed considerable heterogeneity in their size, shape, and density. Twelve of these eighteen cases displayed evidence of squamous differentiation and 10 showed characteristic exocrine lumina.

The capability of single neuroendocrine tumors and single neuroendocrine tumor cells to produce more than one immunoreactive hormone is hereby amply confirmed; these broad capabilities are certainly reflected in the heterogeneous granule populations seen by electron microscopy. The synchronous presence of squamous and exocrine features in bronchopulmonary carcinoids indicates that they too are capable of multidirectional differentiation, which should not detract from their being regarded basically as well-differentiated neuroendocrine neoplasms. The clinical significance of strictly defining bronchial carcinoids is underscored by the fact that of 25 cases followed for 2-13 years, only one developed metastases 9 years postoperatively.     

Role of Histological Criteria and Immunohistochemical Markers in Predicting Risk of Malignancy in Parathyroid Neoplasms

Parathyroid carcinoma (PC) is a rare neoplasm accounting for 0.5–6 % of primary hyperparathyroidism. Histological criteria are currently considered as established means to diagnose malignancy in parathyroid neoplasms; however, it does not accurately predict the risk of aggressive behaviour of PC. Immunohistochemical (IHC) markers have been used in the literature with variable results. This work was planned to study whether IHC markers would have any added advantage over histology in predicting outcome in parathyroid neoplasms. Two hundred twenty-seven parathyroid neoplasms were reviewed according to older and revised histological criteria. IHC was performed for parafibromin, APC, galectin-3, PGP9.5 and Ki67. Diagnostic categories were correlated with clinical, biochemical, histological features and IHC markers. Chi-square test was used to analyse categorical variables. Review of histology by earlier and revised criteria showed a change in diagnosis of five cases of atypical adenoma (15.1 %), all of which were diagnosed as carcinoma according to earlier criteria. Change in diagnosis did not affect behaviour of disease as none of the cases showed recurrence or metastasis on follow-up. Combination of PF, Gal-3 and PGP9.5 showed 50 % sensitivity, 97.9 % specificity and 95.4 % predictive accuracy for PC. Histological criteria still remains the most established method for predicting risk of malignancy in parathyroid neoplasms irrespective of whether old or revised criteria are used. Combination of positive (Gal-3, PGP9.5) and negative (PF) IHC markers may be used as an adjunct to histology in histological, atypical and malignant parathyroid neoplasms to obviate the need for repeated follow-up.     

Frequent Loss of KAI1 Expression in Squamous and Lymphoid Neoplasms : An Immunohistochemical Study of Archival Tissues

The metastasis suppressor gene KAI1 was identified by its ability to inhibit the formation of pulmonary metastases in experimental models for prostatic carcinoma. Down-regulation of this gene may be correlated with the invasive phenotype in melanomas and colon and bladder carcinomas and with the metastatic phenotype in carcinomas of the lung, breast, prostate, and pancreas. The goal of our study was to establish an immunohistochemical method to detect KAI1 expression in archival tissues. Using cell lines with known KAI1 levels and paraffin-embedded KAI1 positive tissues as controls, we observed strong membrane staining in lymphoid follicular centers and squamous epithelia. We then demonstrated the utility of our assay by studying KAI1 expression in 34 lymphoid and 57 squamous lesions. All eight reactive lymph nodes were KAI1 positive. In contrast, three of 13 follicular small cleaved and five of 13 diffuse large cell lymphomas were KAI1 negative. Seventy-nine percent (37 of 47) of invasive squamous cell carcinomas from the lung (n = 15), head and neck (n = 18), and cervix (n = 14) showed extensive KAI1 down-regulation. Loss of KAI1 expression was also found in a subset of 10 high-grade cervical dysplasias. Our data show that (i) immunohistochemistry is a suitable technique for evaluating KAI1 expression in archival tissues; (ii) KAI1 was not expressed in a subset of both low-grade and high-grade lymphomas; and (iii) there was extensive down-regulation of KAI1 in squamous cell carcinomas, suggestive of an important role of the gene in the suppression of invasion in these malignancies.     

胰岛素样生长因子——Ⅰ在胎儿肝、肾等组织的分布

目的　研究胰岛素样生长因子 (IGFs)对胎儿组织增殖和分化的作用。方法　应用免疫组化 ABC法对16至 2 4周胎龄肝、肾、肾上腺、脾、胸腺等组织 IGF— I阳性细胞进行定位研究。结果　胎儿期内 ,以上器官中均有IGF— I阳性细胞存在 ,不同个体和器官其阳性细胞的数量、反应强弱和表达情况有差异。结论　在人胎发育过程中 ,这些器官组织均能表达 IGF— I,对其增殖分化起着自分泌和旁分泌的作用