Cytokeratins 7 and 20 in primary and secondary mucinous tumors of the ovary: analysis of coordinate immunohistochemical expression profiles and staining distribution in 179 cases

Characterization of tumoricidal activities mediated by a novel immune cell regimen composing interferon-producing killer dendritic cells and tumor-specific cytotoxic T lymphocytes

BACKGROUND

Although immune cell therapy has long been used for treating solid cancer, its efficacy remains limited. Interferon (IFN)-producing killer dendritic cells (IKDCs) exhibit cytotoxicity and present antigens to relevant cells; thus, they can selectively induce tumor-associated antigen (TAA)-specific CD8 T cells and may be useful in cancer treatment. Various protocols have been used to amplify human IKDCs from peripheral sources, but the complexity of the process has prevented their widespread clinical application. Additionally, the induction of TAA-specific CD8 T cells through the adoptive transfer of IKDCs to immunocompromised patients with cancer may be insufficient. Therefore, we developed a method for generating an immune cell-based regimen, Phyduxon-T, comprising a human IKDC counterpart (Phyduxon) and expanded TAA-specific CD8 T cells.

METHODS

Peripheral blood mononuclear cells from ovarian cancer patients were cultured with human interleukin (hIL)-15, hIL-12, and hIL-18 to generate Phyduxon-T. Then, its phenotype, cytotoxicity, and antigen-presenting function were evaluated through flow cytometry using specific monoclonal antibodies.

RESULTS

Phyduxon exhibited the characteristics of both natural killer and dendritic cells. This regimen also exhibited cytotoxicity against primary ovarian cancer cells and presented TAAs, thereby inducing TAA-specific CD8 T cells, as evidenced by the expression of 4-1BB and IFN-γ. Notably, the Phyduxon-T manufacturing protocol effectively expanded IFN-γ-producing 4-1BB+ TAA-specific CD8 T cells from peripheral sources; these cells exhibited cytotoxic activities against ovarian cancer cells.

CONCLUSIONS

Phyduxon-T, which is a combination of natural killer cells, dendritic cells, and TAA-specific CD8 T cells, may enhance the efficacy of cancer immunotherapy.

Case report: Metastatic ovarian mucinous carcinoma to the breast: diagnostic challenges and pitfalls

Metastases to the breast from extramammary sources are extremely rare, with the ovary, primarily high-grade serous carcinoma, being the most common origin. We report a case of breast metastases from advanced stage ovarian mucinous carcinoma in a 48-year-old female- a case hitherto unreported in the literature. The case is noteworthy for its atypical presentation marked by an areolar rash, clinically suggestive of Paget disease of the nipple. This unique clinical scenario, coupled with histopathological examination revealing in-situ-like carcinoma component, posed a diagnostic challenge in discerning the tumour origin. We emphasize the need for heightened awareness among pathologists to avoid misdiagnosing metastatic carcinomas as primary breast tumours, a potential pitfall with significant clinical implications.

An Update on the Role of Immunohistochemistry in the Evaluation of Pancreatic/Liver/Gastrointestinal Luminal Tract Disorders

CONTEXT.—

Immunohistochemistry serves as an ancillary diagnostic tool for a wide variety of neoplastic and nonneoplastic disorders, including infections, workup of inflammatory conditions, and subtyping neoplasms of the pancreas/liver/gastrointestinal luminal tract. In addition, immunohistochemistry is also used to detect a variety of prognostic and predictive molecular biomarkers for carcinomas of the pancreas, liver, and gastrointestinal luminal tract.

OBJECTIVE.—

To highlight an update on the role of immunohistochemistry in the evaluation of pancreatic/liver/gastrointestinal luminal tract disorders.

DATA SOURCES.—

Literature review and authors' research data and personal practice experience were used.

CONCLUSIONS.—

Immunohistochemistry is a valuable tool, assisting in the diagnosis of problematic tumors and benign lesions of the pancreas, liver, and gastrointestinal luminal tract, and also in the prediction of prognosis and therapeutic response for carcinomas of the pancreas, liver, and gastrointestinal luminal tract.

Carcinoma of unknown primary (CUP): an update for histopathologists

Carcinoma of unknown primary (CUP) is a heterogeneous group of metastatic cancers in which the site of origin is not identifiable. These carcinomas have a poor outcome due to their late presentation with metastatic disease, difficulty in identifying the origin and delay in treatment. The aim of the pathologist is to broadly classify and subtype the cancer and, where possible, to confirm the likely primary site as this information best predicts patient outcome and guides treatment. In this review, we provide histopathologists with diagnostic practice points which contribute to identifying the primary origin in such cases. We present the current clinical evaluation and management from the point of view of the oncologist. We discuss the role of the pathologist in the diagnostic pathway including the control of pre-analytical conditions, assessment of sample adequacy, diagnosis of cancer including diagnostic pitfalls, and evaluation of prognostic and predictive markers. An integrated diagnostic report is ideal in cases of CUP, with results discussed at a forum such as a molecular tumour board and matched with targeted treatment. This highly specialized evolving area ultimately leads to personalized oncology and potentially improved outcomes for patients.

Diagnostic roles of PAX8 immunohistochemistry in ovarian tumors

OBJECTIVE

This study aimed to elucidate the diagnostic roles of PAX8 immunohistochemistry in various ovarian tumors.

METHODS

We searched through the PubMed database and selected the eligible studies to perform the meta-analysis. The PAX8 immunohistochemical expression rates of various ovarian tumors, including primary and metastatic carcinomas, were analyzed. In addition, the subgroup analysis based on tumor behaviors was performed.

RESULTS

The PAX8 expression rates were 0.056 (95% confidence interval [CI] 0.008-0.307), 0.400 (95% CI 0.228-0.600), 0.741 (95% CI 0.578-0.857), and 0.738 (95% CI 0.666-0.799) in normal ovary and benign, borderline, and malignant ovarian tumors, respectively. The PAX8 expression rates of serous and transitional cell carcinomas were 0.937 (95% CI 0.882-0.967) and 0.918 (95% CI 0.841-0.959). In addition, the PAX8 expression rate of mucinous carcinomas was 0.393 (95% CI 0.285-0.512). However, metastatic carcinomas showed a significantly lower PAX8 expression rate than primary ovarian cancers (P < 0.001 in the meta-regression test). In cytologic specimens, PAX8 expression rates of serous and endometrioid carcinomas were 0.905 (95% CI 0.832-0.948) and 0.714 (95% CI 0.327-0.928), respectively.

CONCLUSION

PAX8 expression rate was significantly higher in serous ovarian tumors than in mucinous ovarian tumors. In addition, PAX8 expression rates were significantly higher in primary ovarian cancers than in metastatic carcinomas.

A pancreatic adenocarcinoma mimicking hepatoid carcinoma of uncertain histogenesis: A case report and literature review

In rare cases, metastatic adenocarcinomas of different origin may exhibit the features of hepatoid carcinoma (HC), a rare malignant epithelial tumor, most commonly occurring in the ovaries and stomach, as well as in the pancreas and biliary ducts. A case of a 72-year-old female patient who developed a highly aggressive, poorly differentiated pancreatic ductal adenocarcinoma with peritoneal carcinomatosis, demonstrating hepatoid differentiation upon conventional hematoxylin and eosin staining is reported in the present study. The patient presented with severe abdominal pain, and the radiological investigations performed revealed ovarian and hepatic tumor masses and peritoneal lesions, which were surgically removed. The gross examination of the peritoneum and omentum revealed multiple solid, firm, grey-white nodules, diffusely infiltrating the adipose tissue. The microscopic examination revealed a malignant epithelial proliferation, composed of polygonal cells with abundant eosinophilic cytoplasm and irregular, pleomorphic nuclei. Certain cells presented with intracytoplasmic mucus inclusions, raising suspicion of a HC with an uncertain histogenesis. Immunohistochemical staining was performed, and the tumor cells were found to be positive for cytokeratin (CK)7, CK18 and mucin 5AC, whereas negative staining for CK20, caudal-type homeobox transcription factor 2, α-fetoprotein, paired box gene 8, GATA-binding protein 3 and Wilms tumor 1 were documented. Thus, the diagnosis of metastatic pancreatic adenocarcinoma was established. The main aim of the present study was to provide further knowledge concerning poorly differentiated metastatic adenocarcinoma resembling HC, emphasizing the histopathological and immunohistochemical features of these malignant lesions and raising awareness of the diagnostic difficulties that may arise, as well as the importance of the use immunohistochemistry in differentiating carcinomas of uncertain histogenesis.

Rare Epithelial Ovarian Cancers: Low Grade Serous and Mucinous Carcinomas

The ovarian epithelial cancer histotypes can be divided into common and rare types. Common types include high-grade serous ovarian carcinomas and the endometriosis-associated cancers, endometrioid and clear-cell carcinomas. The less common histotypes are mucinous and low-grade serous, each comprising less than 10% of all epithelial carcinomas. Although histologically and epidemiologically distinct from each other, these histotypes share some genetic and natural history features that distinguish them from the more common types. In this review, we will consider the similarities and differences of these rare histological types, and the clinical challenges they pose.

Histopathological Evaluation and Molecular Diagnostic Tests for Peritoneal Metastases with Unknown Primary Site-a Review

Cancer of unknown primary (CUP) is a well-studied entity with guidelines available for the management of patients with CUP. The peritoneum represents one of the metastatic sites in CUP, and peritoneal metastases (PM) could present as CUP. PM of unknown origin remains a poorly studied clinical entity. There is only one series of 15 cases, one population-based study, and few other case reports on this subject. Studies on CUP, in general, cover some common tumour histological types like adenocarcinomas and squamous carcinomas. Some of these tumours may have a good prognosis though majority have high-grade disease with a poor long-term outcome. Some of the histological tumour types commonly seen in the clinical scenario of PM like mucinous carcinoma have not been studied. In this review, we divide PM into five histological types-adenocarcinomas, serous carcinomas, mucinous carcinomas, sarcomas and other rare varieties. We provide algorithms to identify the primary tumour site using immunohistochemistry when imaging, and endoscopy fails to establish the primary tumour site. The role of molecular diagnostic tests for PM or unknown origin is also discussed. Current literature on site-specific systemic therapy based on gene expression profiling does not show a clear benefit of this approach over empirical systemic therapies.

Primary intestinal type mucinous adenocarcinoma of the ovary diagnosed during pregnancy – Maternal and neonatal treatment and outcomes: A case report

The incidence of ovarian cancer during pregnancy is low. Most adnexal tumors removed during pregnancy are benign, with ovarian carcinomas found in approximately 1: 10,000–1: 50,000 pregnancies. Literature on this disease is scarce and consists mostly of retrospective studies and case reports. We report the case of a pregnant patient who presented with a primary intestinal-type mucinous adenocarcinoma of the ovary and underwent unilateral salpingo-oophorectomy, with no additional surgical or chemotherapy treatment after the histological diagnosis, despite an infiltrative stromal invasion pattern. To the best of our knowledge, no such case has been previously reported. Conservative treatment in this case of early ovarian carcinoma is possible during pregnancy and should be performed in the Department of Gynecological Oncology and Obstetrics of a tertiary referral hospital. Given the possibility of disease recurrence, such patients require strict clinical oncological surveillance, specialized prenatal care, and assistance from a multidisciplinary team to improve the maternal and perinatal outcomes.

Update on Prognostic and Predictive Markers in Mucinous Ovarian Cancer

This review includes state-of-the-art prognostic and predictive factors of mucinous ovarian cancer (MOC), a rare tumor. Clinical, pathological, and molecular features and treatment options according to prognosis are comprehensively discussed. Different clinical implications of MOC are described according to the The International Federation of Gynecology and Obstetrics (FIGO) stage: early MOC (stage I-II) and advanced MOC (stage III-IV). Early MOC is characterized by a good prognosis. Surgery is the mainstay of treatment. Fertility-sparing surgery could be performed in patients who wish to become pregnant and that present low recurrence risk of disease. Adjuvant chemotherapy is not recommended, except in patients with high-risk clinical and pathological features. Regarding the histological features, an infiltrative growth pattern is the major prognostic factor of MOC. Furthermore, novel molecular biomarkers are emerging for tailored management of early-stage MOC. In contrast, advanced MOC is characterized by poor survival. Radical surgery is the cornerstone of treatment and adjuvant chemotherapy is recommended, although the efficacy is limited by the intrinsic chemoresistance of these tumors. Several molecular hallmarks of advanced MOC have been described in recent years (e.g., HER2 amplification, distinct methylation profiles, peculiar immunological microenvironment), but target therapy for these rare tumors is not available yet.

Mucinous carcinoma of the breast: distinctive histopathologic and genetic characteristics

Mucinous carcinoma is a rare histologic type of breast cancer that, when classified with favorable histology, can be treated with different therapeutic options. This study reviews the histologic findings of mucinous carcinoma that support or exclude favorable histology and emphasizes the necessity of an appropriate gross examination with radiologic findings for an accurate diagnosis. In addition, unusual findings such as micropapillary arrangements and lobular differentiation in mucinous carcinoma and their implications for prognosis and treatment are reviewed. Mucinous carcinoma involves upregulation of MUC2, a mucus-associated gene common in mucinous carcinoma of the breast as well as various other organs. In mucinous carcinoma, the fraction of genome altered and tumor mutation burden are lower than those of invasive carcinoma of no special type, the most common histology of breast cancer. In addition, the genetic alterations found in mucinous carcinoma are diverse, unlike the pathognomonic genetic alterations observed in other histologic types of breast cancer. These genetic features support the importance of conventional microscopic evaluations for the pathologic differential diagnosis of mucinous carcinoma of the breast in routine practice. A variety of breast lesions, including mucinous cystadenocarcinoma and mucocele-like lesions, as well as mucinous carcinoma from other organs, can mimic mucinous carcinoma of the breast. In order to obtain an accurate pathologic diagnosis, careful evaluation of the overall histopathologic characteristics and ancillary testing are required to provide information on appropriate treatment and prognosis.

Mucinous Borderline Tumor Associated with Mesonephric-like Proliferation: Further Evidence for a Possible New Origin of Ovarian Mucinous Neoplasms

Some ovarian mucinous tumors are thought to originate from Brenner tumors and teratomas; however, data are limited on what could be the origin for the remaining tumors. We report a new case of ovarian mucinous borderline tumor/atypical proliferative mucinous tumor (MBT/APMT) co-existing with a mesonephric-like proliferation (MLP)/mesonephric-like hyperplasia (MLH). The patient was a 58-year-old woman who presented with a pelvic mass and abdominal pain. Pathology demonstrated an 11 cm MBT/APMT in the left ovary. In addition, the tumor contained one focal area (<1% of total tumor volume) of MLP/hyperplasia adjacent to, or intimately admixed with, mucinous epithelium, with an immunophenotype of diffuse Pax8 and Gata3 expression and negative TTF-1, ER, and PR staining. Pax8 was also weakly positive in the MBT/APMT component. Some mesonephric-like glands partially exhibited gastrointestinal-type mucinous metaplasia/differentiation. A polymerase chain reaction (PCR)-based Sanger sequencing demonstrated that a KRAS G12V mutation was present in both MLP/MLH and MBT/APMT components, providing further evidence to support their clonal relationship. We previously reported a series of similar cases and demonstrated a novel association between MLP, mesonephric-like adenocarcinoma and ovarian mucinous tumor. It is conceivable that benign MLPs may have ability to differentiate to lineage-specific mucinous lesions, and, as such, they may serve as a possible new origin of some ovarian mucinous neoplasms; in particular, Pax8-positive tumors. The current case provides additional evidence to support this theory.

Metastatic Ovarian Mucinous Carcinoma Presenting as Ileocecal Adenocarcinoma: A Case Report

Colorectal invasion is an unusual late-stage presentation of metastatic primary mucinous ovarian cancer. In this article, we report a fatal case of a 65-year-old female who presented to our clinic with progressive weight loss, severe constipation, and postprandial early satiety. She underwent an esophagogastroduodenoscopy (EGD) and colonoscopy. Direct visualization during colonoscopy revealed acute inflammation with ulceration and highly atypical glands in the ileocecal valve. The initial biopsy was unremarkable, and a repeat biopsy was performed due to high suspicion of malignancy. The repeat biopsy revealed poorly differentiated, invasive colon adenocarcinoma with partial mucinous features. The patient was referred to the surgery service. While planning for surgical resection, they obtained a CT abdomen and pelvis, which revealed a large ovarian mass and peritoneal carcinomatosis. Immunohistochemistry for the tumor cells was positive for pancytokeratin and cytokeratin 7, partially positive (up to 20%) for cytokeratin 20 and CDX2, and negative for estrogen receptors, monoclonal carcinoembryonic antigen (CEA), and synaptophysin. This immunophenotypic pattern is strongly consistent with metastatic mucinous carcinoma of ovarian origin.

Cytokeratin 7 and cytokeratin 20 expression in cancer: A tissue microarray study on 15,424 cancers

Combined analysis of cytokeratin 7 (CK7) and cytokeratin 20 (CK20) is often used for assessing the origin of metastatic cancer. To evaluate the diagnostic utility of CK7 and CK20, tissue microarrays containing 15,424 samples from 120 different tumor types and subtypes and 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. CK7 positivity was seen in 52% (8.7% weak, 5.9% moderate, 37% strong) and CK20 positivity in 23% (5.1% weak, 3.4% moderate, 15% strong) of interpretable tumors. Of 8390 positive tumors, 1181 (14%) showed positivity for CK7 and CK20, 5380 (64%) showed positivity for CK7 alone, and 1829 (22%) showed positivity for CK20 alone. CK20 predominated in gastrointestinal tract, urothelial and Merkel cell carcinomas. CK7 was usually negative in prostate cancer and colorectal cancer. Combined evaluation of CK7/CK20 revealed the best diagnostic utility in CK20 positive tumors, where CK7 negativity is often linked to colorectal origin while CK7 positivity argues for urothelial origin or mucinous ovarian cancer. Associations with unfavorable tumor features were found for cytokeratin 7 loss in breast cancer of no special type, urothelial and renal cell carcinomas, for CK7 overexpression in high-grade serous ovarian and gastric cancer, and for CK20 overexpression in urothelial carcinoma. CK20 loss was linked to MSI in gastric (p = 0.0291) and colorectal adenocarcinoma (p < 0.0001). These analyses provide comprehensive data on the frequency of CK7 and CK20 immunostaining - alone or in combination - in human cancers. These data facilitate interpretation of CK7/CK20 immunostaining in cancers.

Novel Therapeutic Strategies for Refractory Ovarian Cancers: Clear Cell and Mucinous Carcinomas

Ovarian cancer has the worst prognosis among gynecological cancers. In particular, clear cell and mucinous carcinomas are less sensitive to chemotherapy. The establishment of new therapies is necessary to improve the treatment outcomes for these carcinomas. In previous clinical studies, chemotherapy with cytotoxic anticancer drugs has failed to demonstrate better treatment outcomes than paclitaxel + carboplatin therapy. In recent years, attention has been focused on treatment with molecular target drugs and immune checkpoint inhibitors that target newly identified biomarkers. The issues that need to be addressed include the most appropriate combination of therapies, identifying patients who may benefit from each therapy, and how results should be incorporated into the standard of care for ovarian clear cell and mucinous carcinomas. In this article, we have reviewed the most promising therapies for ovarian clear cell and mucinous carcinomas, which are regarded as intractable, with an emphasis on therapies currently being investigated in clinical studies.

Gynaecological or gastrointestinal origin? Recognising Müllerian neoplasms with gastrointestinal phenotype and determining the primary site in selected entities

Recognising metastatic gastrointestinal and pancreatobiliary tumours to gynaecological sites may be challenging, as primary Müllerian tumours can demonstrate similar histological features. Endocervical adenocarcinomas can be of gastric and intestinal types, endometrial lesions may show gastrointestinal phenotype, and finally, mucinous tumours with secondary involvement of the ovaries may mimic primary neoplasms. The aim of this review is to address selected neoplastic entities of the gynaecological tract with gastric and intestinal differentiation and provide helpful clinical and pathological parameters for the diagnosis. A brief overview of metastatic tumours originating from the gastrointestinal and pancreaticobiliary tracts is also provided, including the most common pathological features.

Ovarian Mucinous Carcinoma in a Pediatric Patient With Maroteaux-Lamy Syndrome

Mucopolysaccharidoses (MPS) are autosomal recessive lysosomal storage disorder (LSD). Mucinous ovarian cancer is a rare tumor and seldom encounters among adolescents. Here we describe an adolescent female with MPS type VI diagnosed with mucinous ovarian cancer. To our knowledge, this is the first case report of ovarian mucinous carcinoma in a patient with MPS. The association between MPS and cancer has never been described so far, but some LSD are known to have an increased risk of malignancies. The pathogenetic link between LSD and cancer is not well understood. Several potential mechanisms have been proposed for pathogenesis, which include chronic inflammation, abnormal function of activated macrophages, and genetic modifiers. Further studies are required, to understand the role of LSD in cancer.

Ovarian Metastasis from Pancreatic Ductal Adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) has a high propensity for systemic dissemination. Ovarian metastases are rare and poorly described.

METHODS

We identified PDAC cases with ovarian metastasis from a prospectively maintained registry. We reported on the association between outcomes and clinicopathologic factors. Recurrence-free (RFS) and overall survival (OS) were calculated using Kaplan-Meier analysis.

RESULTS

Twelve patients with PDAC and synchronous or metachronous ovarian metastases were identified. Nine patients (75%) underwent pancreatectomy for localized PDAC and developed metachronous ovarian recurrence. The median OS for all patients was 25.4 (IQR:15.4-82.9) months. For the nine patients with metachronous ovarian metastasis, the median RFS and OS were 14.2 (IQR:7.2-58.3) and 44.6 (IQR:18.6-82.9) months, respectively. Nodal disease, poor grade, vascular invasion in the pancreatic primary, and bilateral ovarian disease tended to confer worse outcomes.

CONCLUSION

Patients with resected PDAC and ovarian recurrence tend to have a comparable disease course to more common patterns of recurrence. Primaries with nodal disease, poorer grade, vascular invasion, and bilateral ovarian disease were indicative of more aggressive disease biology. The ideal management remains largely unknown, and future collaborative efforts should optimize therapeutic strategies.

Ovarian mucinous and seromucinous neoplasms: problematic aspects and modern diagnostic approach

The morphological spectrum of primary ovarian mucinous and seromucinous tumours is broad and presents an array of diagnostic challenges, many unique to these tumour types. This reflects the heterogeneous nature of these lesions, their varied histogenesis and evolving classification systems over recent decades, with further modification to the seromucinous category incorporated in the recently published 5^th edition of the WHO Classification of Female Genital Tumours. In this review we provide an update on the classification of these neoplasms and discuss their histogenesis and diverse morphology, focusing on areas which are diagnostically problematic. We also cover tumour grading, differential diagnosis, immunohistochemistry, the recent elucidation of the molecular underpinnings of ovarian mucinous neoplasia and discuss the gross and intraoperative handling of these tumours. A number of diagnostic issues remain unresolved highlighting the importance of further research on this front, as well as a multidisciplinary approach in the care of patients with ovarian mucinous and seromucinous neoplasia.

Primary mucinous ovarian tumors vs. ovarian metastases from gastrointestinal tract, pancreas and biliary tree: a review of current problematics

Background

Making the distinction between primary mucinous and metastatic ovarian tumors is often difficult, especially in tumors with a primary source from the gastrointestinal tract, pancreas and biliary tree. The aim of the following paper is to provide an overview of the problematics, with a focus on the possibilities of the differential diagnosis at the macroscopic, microscopic and immunohistochemical level.

Main body

The three main aspects of mucinous ovarian tumors are described in detail, including the comparison of the available diagnostic algorithms based on the evaluation of mostly macroscopic features, characterization of the spectrum of microscopic features, and a detailed analysis of the immunophenotype comparing 20 antibodies with the assessment of their statistical significance for differential diagnosis purposes. Specific features, including Krukenberg tumor and pseudomyxoma peritonei, are also discussed.

Conclusion

Despite the growing knowledge of the macroscopic and microscopic features of ovarian mucinous tumors and the availability of a wide range of immunohistochemical antibodies useful in this setting, there still remains a group of tumors which cannot be precisely classified without close clinical-pathological cooperation.

[Borderline ovarian tumours: CNGOF Guidelines for clinical practice - Biopathology of ovarian borderline tumors]

OBJECTIVES

Ovarian borderline tumors (OBT) represent a heterogeneous group of lesions with specific management for each histological subtype. Thus, the correct histological diagnosis is mandatory.

MATERIAL AND METHODS

References were searched by PubMed from January 2000 to January 2018 and original articles in French and English literature were selected.

RESULTS AND CONCLUSIONS

OBT should be classified according to the last WHO classification. Any micro-invasion (foci<5mm) or microcarcinoma (foci<5mm with nuclear atypia and desmoplastic stromal reaction) should be indicated in the pathology report. In case of serous OBT, variants (classical or the micropapillary/cribriform) should be indicated (grade C). The peritoneal implants associated with OBT, should be classified as invasive or noninvasive, according to the extension into the underlying adipous tissue. If no adipous tissue is seen the term undetermined should be used (grade B). In case of mucinous OBT bilateral and/or with peritoneal implants or peritoneal pseudomyxoma a search for primitive gastrointestinal, appendiceal or biliopancreatic tumor should be performed (grade C). In case of OBT, a thorough sampling of the tumor is recommended, with 1 block/cm and 2 blocks/cm in case of mucinous OBT, serous OBT micropapillary variant, OBT with intraepithelial carcinoma or/and micro-invasion. Peritoneal implants should be examined in toto. Omentum without macroscopic lesion should be sampled in 4 to 6 blocks (grade C). In case of ovarian cyst suspicious for OBT, fine needle aspiration is not recommended (grade C). In case of ovarian tumor suspicious for OBT, intraoperative examination should be performed by a gynecological pathologist (grade C).

An Update on the Role of Immunohistochemistry in the Evaluation of Gastrointestinal Tract Disorders

As in other organ systems, immunohistochemistry (IHC) serves as an ancillary diagnostic tool for a wide variety of neoplastic and non-neoplastic disorders, including infections, work-up of inflammatory conditions, and subtyping neoplasms of the gastrointestinal (GI) tract. In addition, IHC is also used to detect a variety of prognostic and predictive molecular biomarkers for carcinomas of the GI tract. The purpose of this review is to highlight the use of IHC in common diagnostic scenarios throughout the tubular GI tract. The clinical indication and guidelines for performing IHC for detecting Helicobacter pylori is discussed along with role of gastrin and neuroendocrine markers in the diagnosis of autoimmune metaplastic atrophic gastritis. The major portion of this review discusses the use of IHC in the diagnostic workup of malignant neoplasms of the GI tract, such as adenocarcinoma versus squamous cell carcinoma, workup of poorly differentiated malignant neoplasms, and evaluation of uncommon gastric neoplasms (alpha-feto protein-producing carcinomas) and switch/sucrose-nonfermenting complex-deficient carcinomas. Lastly, localization of neuroendocrine tumors of unknown origin to aid clinical management, as well as HPV-driven anal neoplasia and IHC in the workup of basaloid anal neoplasms are also reviewed.

Essentials for Pathological Evaluation of Peritoneal Surface Malignancies and Synoptic Reporting of Cytoreductive Surgery Specimens-A review and evidence-based guide

Peritoneal surface oncology has emerged as a subspecialty of surgical oncology, with the growing popularity of surgical treatment of peritoneal metastases comprising of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Pathological evaluation plays a key role in multidisciplinary management but there are still many areas where there are no guidelines or consensus on reporting. Some tumors presenting to a peritoneal surface oncology unit are rare and pathologists my not be familiar with diagnosing and classifying those. In this manuscript, we have reviewed the evidence regarding various aspects of histopathological evaluation of peritoneal tumors. It includes establishing a diagnosis, appropriate classification and staging of common and rare tumors and evaluation of pathological response to chemotherapy. In many instances, the information captured is of prognostic value alone with no direct therapeutic implications. But proper capturing of such information is vital for generating evidence that will guide future treatment trends and research. There are no guidelines/data set for reporting cytoreductive surgery specimens. Based on the authors' experience, a format for handling/grossing and synoptic reporting of these specimens is provided.

The utility of PAX8 and SATB2 immunohistochemical stains in distinguishing ovarian mucinous neoplasms from colonic and appendiceal mucinous neoplasm

Objectives

It is challenging to distinguish between primary ovarian mucinous tumors and metastatic mucinous neoplasms from the lower gastrointestinal tract, including appendiceal tumors. A combination of PAX8 and SATB2 immunohistochemical stains can be used as a diagnostic tool to distinguish between these cases.

Results

Immunostaining for SATB2, PAX8, CK7, CK20 and CDX2 was performed on 50 ovarian mucinous neoplasms (OMN) (39 cystadenomas, 4 borderline and 7 adenocarcinomas), 63 mucinous colorectal carcinoma (CRC), and 9 appendiceal mucinous neoplasms (AMN) [8 low grade appendiceal mucinous neoplasms (LAMN) and 1 adenocarcinoma]. PAX8 was positive in 32% of OMN and negative in all CRC and AMN cases. SATB2 was expressed in 2.0% of OMN, 77.8% of AMN, and 49.2% of CRC cases. CK7 was positive in 78.0% of OMN, 33.3% of AMN, and 9.5% of CRC cases. CK20 was expressed in 24.0% of OMN, 88.9% of OMN, and 87.3% of CRC cases. CDX2 was positive in 14.0% of OMN, 100% of AMN, and 90.5% of CRC cases. PAX8 can differentiate between OMN and AMN with high specificity but low sensitivity. CDX2 is the most sensitive marker for CRC and AMN, whereas SATB2 has better specificity.

Practical Application of Lineage-Specific Immunohistochemistry Markers: Transcription Factors (Sometimes) Behaving Badly

CONTEXT.—

Transcription factors (TFs) are proteins that regulate gene expression and control RNA transcription from DNA. Lineage-specific TFs have increasingly been used by pathologists to determine tumor lineage, especially in the setting of metastatic tumors of unknown primary, among other uses. With experience gathered from its daily application and increasing pitfalls reported from immunohistochemical studies, these often-touted highly specific TFs are not as reliable as once thought.

OBJECTIVES.—

To summarize the established roles of many of the commonly used TFs in clinical practice and to discuss known and potential sources for error (eg, false-positivity from cross-reactivity, aberrant, and overlap "lineage-specific" expression) in their application and interpretation.

DATA SOURCES.—

Literature review and the authors' personal practice experience were used. Several examples selected from the University Health Network (Toronto, Ontario, Canada) are illustrated.

CONCLUSIONS.—

The application of TF diagnostic immunohistochemistry has enabled pathologists to better assess the lineage/origin of primary and metastatic tumors. However, the awareness of potential pitfalls is essential to avoid misdiagnosis.

Mucinous Ovarian Tumors

Ovarian mucinous tumors range from benign cystadenomas to borderline tumors to frankly malignant adenocarcinomas, and may display either intestinal-type morphology or, less frequently, endocervical-type differentiation. The latter category has been the subject of recent controversy owing to its morphologic overlap with so-called "seromucinous" ovarian tumors, a group that shares more molecular features with endometrioid tumors than it does with either serous or mucinous ovarian neoplasias. Endocervical-type differentiation in ovarian mucinous tumors may also represent an endocervical metastasis. Distinction of primary ovarian mucinous tumors from gastrointestinal metastases can be difficult, as the morphology of intestinal-type ovarian mucinous primaries sometimes differs only subtly if at all from gastrointestinal metastases.

Pancreaticobiliary metastasis presenting as primary mucinous ovarian neoplasm: A systematic literature review

True primary mucinous ovarian carcinomas are rarer than originally thought and their clinical behavior and treatment response are different than more common epithelial ovarian carcinomas. Secondary ovarian neoplasms often mimic the clinical and histological features of mucinous ovarian cancer making their diagnosis, and therefore treatment, more difficult. Misdiagnosis can have a significant impact on both treatment and prognosis. The majority of these secondary ovarian neoplasms arise from the gastrointestinal tract, with mucinous histology often of pancreaticobiliary origin. Our study objective was to review current evidence distinguishing pancreaticobiliary ovarian metastasis from primary mucinous ovarian carcinoma. We utilized a PubMed search using MeSH terms and selected articles were reviewed, synthesized and summarized. Thirty-nine articles were included in the review. The clinical, gross, histological and immunohistochemical features distinguishing primary mucinous ovarian carcinomas from pancreaticobiliary ovarian metastasis were identified. Compared to primary mucinous ovarian carcinoma, metastatic pancreaticobiliary tumors are more often bilateral, <10 cm, have irregular external surface and surface implants, display an infiltrative pattern of invasion and stain for MUC1 and CK17. Primary ovarian mucinous tumors rarely (<3%) have signet ring cells or involvement of the hilum. Metastatic mucinous tumors mimic their primary mucinous ovarian counterparts and their clinical and histopathological features overlap in many ways. However, these metastatic tumors have features that can help differentiate them from primary mucinous carcinoma. With a high index of suspicion and knowledge of the reviewed features, distinguishing these tumors will continue to become easier.

•

Primary ovarian and metastatic pancreaticobiliary tumors present similarly.

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Histologic findings can differentiate primary from metastatic ovarian tumors.

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Bilaterality, size, surface appearance can differentiate primary versus metastatic.

SATB2 Versus CDX2: A Battle Royale for Diagnostic Supremacy in Mucinous Tumors

CONTEXT.—

Metastatic mucinous tumors present a diagnostic challenge for pathologists as tumor histomorphology is often nonspecific and optimal immunoprofiles are still under investigation.

OBJECTIVE.—

To present a head-to-head comparison of special AT-rich sequence-binding protein 2 (SATB2) and caudal type homeobox 2 (CDX2) expression in a diverse array of primary mucinous tumors.

DESIGN.—

SATB2 and CDX2 immunohistochemical stains were performed on whole sections from 44 mucinous colorectal carcinomas and 175 noncolorectal mucinous tumors. A nuclear scoring system measuring intensity (0-3+) and percentage staining (0 = <5%, 1 = 5%-49%, 2 = ≥50%) was implemented, producing an additive histologic score (H-score).

RESULTS.—

SATB2 demonstrated acceptable accuracy at low to moderate expression levels (H-scores of 1-4). With these H-score cutoffs, overall accuracy was greater than 90%. In contrast, CDX2's accuracy rivaled that of SATB2 only at an H-score of 5 (89.0%), as its specificity suffered at lower expression levels (<70.0% at H-scores of 1-4). Using a moderate H-score cutoff of 3 or higher, significant differences for both sensitivity and specificity were identified between SATB2 and CDX2 (P = .01 for sensitivity and P < .001 for specificity), though these stains were near equivalent when each was interpreted as positive at its respective optimal H-score (SATB2 ≥ 3 and CDX2 = 5).

CONCLUSIONS.—

SATB2 is a more accurate marker of colorectal origin across a variety of expression levels compared with CDX2 when applied to mucinous tumors from a host of primary sites. However, these stains are near equivalent when each is interpreted at its optimal expression level.

Diagnostic Utility of SATB2 in Metastatic Krukenberg Tumors of the Ovary: An Immunohistochemical Study of 70 Cases With Comparison to CDX2, CK7, CK20, Chromogranin, and Synaptophysin

SATB2 is a sensitive marker for colorectal adenocarcinomas. No study has investigated its diagnostic utility in metastatic Krukenberg tumors (MKTs) of the ovary. Here we performed immunohistochemical staining SATB2 in 70 MKTs of various origins (stomach 27, colorectum 13, appendix 20 including 19 metastatic adenocarcinomas ex goblet cell carcinoids [AdexGCC] and 1 conventional poorly differentiated carcinoma with signet ring cells, breast 5, bladder 3, lung 2) to assess its diagnostic utility. We also compared SATB2 with CDX2, CK7, CK20, chromogranin, and synaptophysin in MKTs of gastric origin (MKTs-stomach), those of colorectal origin (MKTs-colorectum) and those due to appendiceal AdexGCCs (MKT-AdexGCCs) for their sensitivity and specificity to distinguish these tumors. SATB2 staining was seen in 1/27 (4%) MKTs-stomach (40% cells), 7/13 (54%) MKTs-colorectum (mean: 17% cells, median: 7%, range: 2% to 60%), and 19/19 (100%) of MKT-AdexGCCs (mean: 97% cells, median: 100%, range: 80% to 100%) (P<0.01 between any two). SATB2 staining was seen in 1/1 metastatic appendiceal poorly differentiated carcinoma with signet ring cells (5% cells), 1/3 MKTs of bladder origin (60% cells), 0/2 MKTs of pulmonary origin, and 1/5 MKTs of breast origin (10% cells). SATB2 staining was diffuse strong in MKT-AdexGCCs whereas in other MKTs it was focal and weak in the signet ring and nonsignet ring nonglandular cells and from focal weak to diffuse strong in well-formed glands. MKTs-stomach, MKTs-colorectum, and MKT-AdexGCCs showed no significant staining difference in CDX2 (100%, 100%, 100% cases, respectively; P=1.0), CK20 (96%, 100%, 100%, respectively; P=1.0), chromogranin (59%, 31%, 63%, respectively; P>0.05) or synaptophysin (59%, 63%, 84%, respectively; P>0.05) but they had significant difference in CK7 staining (93%, 8%, 42%, respectively; P<0.05). Among these 6 markers, SATB2 is the best one to distinguish MKT-AdexGCCs from MKTs-stomach (100% sensitivity, 96% specificity) and MKTs-colorectum (100% sensitivity and 100% specificity if staining more than 75% tumor cells as the cutoff). In distinguishing MKTs-stomach from MKTs-colorectum, SATB2 is not as good as CK7 which is the best marker. Our results indicate that SATB2 is a highly sensitive marker (100% sensitivity) for metastatic MKT-AdexGCCs with high specificity (100% specificity when showing strong staining in at least 75% cells) among MKTs. SATB2 is a useful marker for determining the primary sites of MKTs of the ovary.

A novel algorithm for better distinction of primary mucinous ovarian carcinomas and mucinous carcinomas metastatic to the ovary

Primary mucinous ovarian carcinomas (MOC) are notoriously difficult to distinguish from mucinous carcinomas metastatic to the ovary (mMC). Studies performed on small cohorts reported algorithms based on tumor size and laterality to aid in distinguishing MOC from mMC. We evaluated and improved these by performing a large-scale, nationwide search in the Dutch Pathology Registry. All registered pathology reports fulfilling our search criteria concerning MOC in the Netherlands from 2000 to 2011 were collected. Age, histology, laterality, and size were extracted. An existing database covering the same timeline containing tumors metastatic to the ovary was used, extracting all mMC, age, size, laterality, and primary tumor location. Existing algorithms were applied to our cohort. Subsequently, an algorithm based on tumor histology, laterality, and a nomogram based on age and size was created for differentiating MOC and mMC. We identified 735 MOC and 1018 mMC. Patients with MOC were significantly younger and MOC were significantly larger and more often unilateral than mMC. Signet ring cell carcinomas were rarely primary. Our algorithm used signet ring cell histology, bilaterality, and a nomogram integrating patient age and tumor size to diagnose mMC. Sensitivity and specificity for mMC was 90.1% and 59.0%, respectively. Applying existing algorithms on our cohort yielded a far lower sensitivity. The algorithm described here using tumor histology, laterality, size, and patient age has higher sensitivity but lower specificity compared to earlier algorithms and aids in indicating tumor origin, but for conclusive diagnosis, careful integration of morphology, immunohistochemistry, and clinical and imaging data is recommended.

Updates in Effusion Cytology

Effusion cytology plays multiple roles in the management of benign and malignant disease, from primary diagnosis to tissue allocation for ancillary diagnostic studies and biomarker testing of therapeutic targets. This article summarizes recent advances in pleural effusion cytology, with a focus on the practical application of immunohistochemical markers, cytogenetic techniques, flow cytometry, and molecular techniques for the diagnosis and management of primary and secondary neoplasms of the pleura.

Diagnostic algorithm for determining primary tumor sites using peritoneal fluid

This study was conducted to develop a novel algorithm for determining the origin of tumors by combining analysis of cluster patterns with immunocytochemistry (ICC) for markers in cells from fine-needle aspirates of ascites. We used LBC, based on SurePath^TM (BD Diagnostics) technology, to screen 96 peritoneal fluid samples from patients with known malignancies and from 10 control patients with cirrhosis. Following dual ICC staining for cytokeratin 7 (CK7) and paired box gene 8 (PAX8), we developed an algorithm using immunoreactivity and three-dimensional (3D) cluster patterns to correlate staining and 3D cluster patterns with common primary origins that included stomach, ovarian, pancreatobiliary tract, colon, lung, and breast cancers. With the application of an automatic digitalized image analyzer, competence performance was analyzed using receiver operating characteristics (ROC) curve analysis. CK7 and PAX8 staining and 3D cluster patterns were used to differentiate primary origins. Samples from patients with stomach cancer were no 3D cluster /CK7⁺/PAX8^- with area under the curve (AUC) of 0.8699 in ROC curve analysis. Samples from ovarian cancer patients were large 3D cluster/CK7⁺/PAX8⁺ with AUC of 0.9812. Samples from pancreatobiliary tract cancer patients were small 3D cluster/CK7⁺/PAX8^- with AUC of 0.8772. The remaining cancer samples, including breast, lung and colon cancer samples, had similar patterns of large 3D clusters/CK7⁺/PAX8^- with AUC of 0.882, especially for lung cancer. SurePath^TM technology, using 3D cluster patterns and dual ICC for CK7 and PAX8 in peritoneal fluid samples, can provide important information for determining specific primary origins in cases of unknown primary carcinoma.

Ovarian metastases from gallbladder mimics primary ovarian neoplasm in young patient: a case report

Background

Gallbladder cancer is unusually seen but can result in highly mortality rate. It makes challenge to diagnose for clinicians due to present asymptomatic or non-specific clinical presentation including abdominal pain, anorexia. It usually also accompanies with cholelithiasis (incidence is 1–2%) and incidentally detected by radiologic examination such as ultrasound, computed tomography or intra-operative intervention accidentally. Gallbladder cancer results in highly fatal malignancy because it is difficult to early detect. The ovarian metastases from gallbladder mimics primary neoplasm isn’t seen before and mentioned in English literatures before.

Case presentation

A 28-year-old woman suffered from intermittently lower abdominal tenderness and nausea after meals for 3 years. The abdominal ultrasound revealed a right ovarian mass with fluid accumulation and the contrast CT of abdomen revealed a gallbladder fundus mass and liver tumor lesion located at segment 4. We arranged surgical intervention with radical cholecystectomy and debulking operation with salpingo-oophorectomy. The pathologic report revealed adenocarcinoma of gallbladder with liver, peritoneum, and right ovarian invasion. After surgical intervention, she also received adjuvant chemotherapy with Gemcitabine, Cetuximab, Cisplatin and Cyberknife.

Conclusion

The non-specific symptoms make the challenge to difference the primary malignant neoplasm. The rarely diagnosis must take in consider if the gastrointestinal tract tumours coexist with ovarian tumours.

A guided tour of selected issues pertaining to metastatic carcinomas involving or originating from the gynecologic tract

Epithelial metastases originating from the gynecologic tract or secondarily involving it frequently display a different morphology when compared to the primary tumor. Furthermore, issues such as modes of metastasis, appropriate nomenclature and prognostic significance remain subjects of discussion and some skepticism. In this review, we will discuss: metastases to uterine adnexa; serous tubal intraepithelial carcinoma (STIC); serous borderline tumors; metastases from the uterine corpus; and “synchronous” endometrial and ovarian tumors. Three additional themes that will run through the discussions are those that are peculiar, although not restricted to the gynecologic tract: metastasis from non-invasive primary tumors, metastases that look benign and metastases that are benign or clinically indolent.

Quantitative mass spectrometry analysis reveals a panel of nine proteins as diagnostic markers for colon adenocarcinomas

Adenocarcinomas are cancers originating from the gland forming cells of the colon and rectal lining, and are known to be the most common type of colorectal cancers. The current diagnosis strategies for colorectal cancers include biopsy, laboratory tests, and colonoscopy which are time consuming. Identification of protein biomarkers could aid in the detection of colon adenocarcinomas (CACs). In this study, tissue proteome of colon adenocarcinomas (n = 11) was compared with the matched control specimens (n = 11) using isobaric tags for relative and absolute quantitation (iTRAQ) based liquid chromatography-mass spectrometry (LC-MS/MS) approach. A list of 285 significantly altered proteins was identified in colon adenocarcinomas as compared to its matched controls, which are associated with growth and malignancy of the tumors. Protein interaction analysis revealed the association of altered proteins in colon adenocarcinomas with various transcription factors and their targets. A panel of nine proteins was validated using multiple reaction monitoring (MRM). Additionally, S100A9 was also validated using immunoblotting. The identified panel of proteins may serve as potential biomarkers and thereby aid in the detection of colon adenocarcinomas.

Relatively Poor Survival of Mucinous Ovarian Carcinoma in Advanced Stage: A Systematic Review and Meta-analysis

OBJECTIVE

Overall, patients with mucinous ovarian carcinoma (MOC) are considered to have a better prognosis compared with the whole group of nonmucinous carcinomas. However, some studies indicate that patients with advanced-stage MOC might have a worse prognosis than those with advanced-stage serous ovarian carcinoma (SOC). We carried out a systematic review and meta-analysis of the current literature.

MATERIALS AND METHODS

A comprehensive literature search was carried out identifying 19 articles that compare survival of patients with MOC and patients with SOC. Meta-analyses were performed for risk ratio (RR) and hazard ratio (HR) for all International Federation of Gynecology and Obstetrics stages together, as well as for early- and advanced-stage diseases separately.

RESULTS

Overall, patients with MOC showed a lower risk of dying within 5 years (RR, 0.67; 95% confidence interval [CI], 0.64-0.69; n = 45 333) and a longer survival (HR, 0.66; 95% CI, 0.58-0.75; HR, 0.88; 95% CI, 0.78-0.98, for univariate and multivariate analyses, respectively; n = 5540) compared with those with SOC. In contrast, in advanced-stage (International Federation of Gynecology and Obstetrics stages III and IV) disease, patients with MOC have a higher risk of dying within 5 years (RR, 1.15; 95% CI, 1.13-1.17; n = 36 113) and a shorter survival (HR, 1.82; 95% CI, 1.71-1.94; n = 19 907).

CONCLUSIONS

Patients with advanced-stage MOC have a significantly worse prognosis compared with patients with SOC, whereas in early stage, the prognosis of patients with MOC is better.

SATB2 is a supportive marker for the differentiation of a primary mucinous tumor of the ovary and an ovarian metastasis of a low-grade appendiceal mucinous neoplasm (LAMN): A series of seven cases

The differentiation between a primary mucinous ovarian neoplasm and an extra-ovarian metastasis in the ovary is often challenging in the histopathologic practice. Among various ovarian metastases from the gastro-intestinal tract the low-grade appendiceal mucinous neoplasm (LAMN) is an important differential diagnosis to consider particularly in case of pseudomyxoma peritonei. A newly recognized marker in the routine diagnostic of a mucinous neoplasm in the ovary is SATB2 (Special AT-rich sequence-binding protein 2). The expression of SATB2 is, within cells of epithelial lineages, mainly restricted to the lower gastro-intestinal tract, indicating colorectal or appendiceal cancer origin. We report seven cases of LAMN, which clinically became apparent due to ovarian metastases in context of pseudomyxoma peritonei or at least small foci of peritoneal tumor spread. An immunohistochemical marker-panel including SATB2, CDX2, CK20, CK7, PAX8, ER and PR revealed a strong expression of SATB2 in all seven cases. On the contrary SATB2-negativity could be demonstrated in the 40 cases of mucinous borderline tumors and primary mucinous carcinomas of the ovary. The histopathologic tentative diagnosis of an ovarian metastasis of LAMN could be confirmed in the findings of the Appendix in six of seven cases. This report supports SATB2 as an additional diagnostic marker for the diagnosis of an ovarian manifestation of LAMN.

Diagnostic immunohistochemistry in gynaecological neoplasia: a brief survey of the most common scenarios

Immunohistochemistry is a valuable adjunct in routine gynaecological pathology. The molecular revolution has redesigned knowledge of gynaecological cancers and refined histological classification. The direct consequence has been the progressive introduction of new immunostainings for diagnostic and classification purposes. Hence, we review the routine diagnostic use of immunohistochemistry in the field of gynaecological neoplasia. We reviewed the immunomarkers useful in gynaecological pathology according to literature revision, our personal experience and research findings. We discuss the application of immunohistochemistry to reach the most accurate diagnosis in morphologically equivocal cases of gynaecological pathology and present the appropriate panel of immunomarkers in the most common scenarios of gynaecological pathology. This short review provides an updated overview of the essential immunohistochemical markers currently used in the diagnostics of gynaecological malignancies along with their molecular rationale.

Practical Immunohistochemistry in Neoplastic Pathology of the Gastrointestinal Tract, Liver, Biliary Tract, and Pancreas

CONTEXT

- Immunomarkers with diagnostic, therapeutic, or prognostic values have been increasingly used to maximize the benefits of clinical management of patients with neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas.

OBJECTIVES

- To review the characteristics of immunomarkers that are commonly used in surgical pathology practice for neoplasms of the gastrointestinal tract, liver, biliary tract, and pancreas, and to summarize the clinical usefulness of immunomarkers that have been discovered in recent years in these fields.

DATA SOURCES

- Data sources include literature review, authors' research data, and personal practice experience.

CONCLUSIONS

- Immunohistochemistry is an indispensable tool for the accurate diagnosis of neoplastic diseases of the gastrointestinal tract, liver, biliary tract, and pancreas. Useful immunomarkers are available to help distinguish malignant neoplasms from benign conditions, determine organ origins, and subclassify neoplasms that are morphologically and biologically heterogeneous. Specific immunomarkers are also available to help guide patient treatment and assess disease aggressiveness, which are keys to the success of personalized medicine. Pathologists will continue to play a critical role in the discovery, validation, and application of new biomarkers, which will ultimately improve patient care.

PAX8 is a potential marker for the diagnosis of primary epithelial ovarian cancer

The present study aimed to investigate the clinical significance of paired-box 8 (PAX8) in primary epithelial ovarian cancer (PEOC). Using immunohistochemical (IHC) staining, the expression of PAX8 in 60 patients with PEOC, 20 patients with ovarian benign lesions and 10 patients with metastatic ovarian cancer (MOC), was examined based on the clinicopathological profiles of the patients. The correlation between PAX8 expression and the clinicopathological parameters or prognosis of patients was statistically analyzed. PAX8 was revealed to be highly expressed in PEOC, but not in MOC, as indicated by IHC staining. The rate of positivity of PAX8 in PEOC was 92% (57/60) with no significant difference of PAX8 expression found between the various pathological types of PEOC (P=0.871). The rate of positivity of PAX8 in ovarian benign tumors was 85%, demonstrating no significant difference in comparison with that of PEOC (P=0.761). PAX8 staining and statistical analysis revealed that the higher the grade of PEOC, the less the cancer cell had differentiated (P=0.033) and the more the cancer had advanced according to International Federation of Gynaecological Oncologists (FIGO) staging (P=0.003). Survival rate statistics showed that PEOC patients with higher PAX8 expression exhibited a shorter postoperative survival rate (P=0.009). PAX8 was specifically expressed in PEOC, and its expression level was associated with the degree of cancer cell differentiation, FIGO stage, and survival rate, indicating that PAX8 is a potential marker for the diagnosis of PEOC.

Dual Immunostain With SATB2 and CK20 Differentiates Appendiceal Mucinous Neoplasms From Ovarian Mucinous Neoplasms

OBJECTIVES

Determination of the primary site of origin for mucinous neoplasms identified in the peritoneal and/or pelvic cavities may be challenging, with major differential diagnoses including appendiceal mucinous neoplasm (AMN) and ovarian mucinous neoplasm (OMN). Special AT-rich sequence binding protein 2 (SATB2) has been shown to be highly selectively expressed in the lower gastrointestinal tract, including the appendix.

METHODS

We investigated the utility of a dual stain (DS) with SATB2 or caudal type homeobox 2 (CDX2) and cytokeratin 20 (CK20) or villin in distinguishing AMNs from OMNs. Tissue microarrays with 40 AMNs and 18 OMNs were stained with SATB2 or CDX2 paired with either CK20 or villin.

RESULTS

SATB2 single stain showed a good sensitivity of 83% and the highest specificity of 78% for AMNs over OMNs among all four stains. DS with SATB2 and villin showed an identical sensitivity of 78% but specificity increased to 94%, while DS with SATB2 and CK20 showed a sensitivity of 80% and a specificity of 100%. In contrast, DS with CDX2 and CK20/villin showed slightly higher sensitivity but much lower specificity.

CONCLUSIONS

DS with SATB2/CK20 shows the greatest potential clinical utility in distinguishing AMNs from OMNs and is superior to DS with CDX2/CK20. Importantly, DS could be helpful for specimens with limited tissues.

Molecular Alterations of TP53 are a Defining Feature of Ovarian High-Grade Serous Carcinoma: A Rereview of Cases Lacking TP53 Mutations in The Cancer Genome Atlas Ovarian Study

The Cancer Genome Atlas has reported that 96% of ovarian high-grade serous carcinomas (HGSCs) have TP53 somatic mutations suggesting that mutation of this gene is a defining feature of this neoplasm. In the current study, 5 gynecologic pathologists independently evaluated hematoxylin and eosin slides of 14 available cases from The Cancer Genome Atlas classified as HGSC that lacked a TP53 mutation. The histologic diagnoses rendered by these pathologists and the accompanying molecular genetic data are the subject of this report. Only 1 case (Case 5), which contained a homozygous deletion of TP53, had unanimous interobserver agreement for a diagnosis of pure HGSC. In 1 case (Case 3), all 5 observers (100%) rendered a diagnosis of HGSC; however, 3 observers (60%) noted that the histologic features were not classic for HGSC and suggested this case may have arisen from a low-grade serous carcinoma (arisen from an alternate pathway compared with the usual HGSC). In 2 cases (Cases 4 and 12), only 3 observers (60%) in each case, respectively, interpreted it as having a component of HGSC. In the remaining 10 (71%) of tumors (Cases 1, 2, 6-11, 13, and 14), the consensus diagnosis was not HGSC, with individual diagnoses including low-grade serous carcinoma, high-grade endometrioid carcinoma, HGSC, metastatic carcinoma, clear cell carcinoma, atypical proliferative (borderline) serous tumor, and adenocarcinoma, not otherwise specified. Therefore, 13 (93%) of the tumors (Cases 1-4 and 6-14) were either not a pure HGSC or represented a diagnosis other than HGSC, all with molecular results not characteristic of HGSC. Accordingly, our review of the TP53 wild-type HGSCs reported in The Cancer Genome Atlas suggests that 100% of de novo HGSCs contain TP53 somatic mutations or deletions, with the exception of the rare HGSCs that develop from a low-grade serous tumor precursor. We, therefore, propose that lack of molecular alterations of TP53 are essentially inconsistent with the diagnosis of ovarian HGSC and that tumors diagnosed as such should be rigorously reassessed to achieve correct classification.

Synchronous Ovarian and Appendiceal Mucinous Neoplasms in the Absence of Pseudomyxoma Peritonei

Background

Synchronous ovarian/appendiceal mucinous neoplasms sometimes occur in the absence of clinical pseudomyxoma peritonei (PMP), which raises a question about whether the 2 tumors could be independent.

Methods

We identified 11 cases of synchronous ovarian/appendiceal mucinous neoplasms without PMP and subclassified them into groups 1 and 2 based on the presence or absence of microscopic peritoneal/ovarian surface mucin deposits. A 7-marker panel (CK7, CK20, CDX2, PAX8, MUC1, MUC2, and MUC5AC) immunohistochemistry was performed on both tumors.

Results

Between the 2 groups, there were no significant differences in age, laterality, size, and histology of ovarian/appendiceal tumors. In group 1, 2 of 4 cases developed PMP later, and both had ovarian surface and contralateral ovarian involvement and appendiceal perforation with microscopic mucin deposits on the peritoneum. No patients in group 2 developed PMP. All group 1 cases showed a high degree of concordance of immunoprofile between the synchronous tumors, with an identical expression of appendiceal pattern in greater than 90% of the markers. In group 2, only 1 of 7 cases showed concordance in all markers.

Conclusions

If peritoneal mucin deposits present, even microscopic and acellular, the synchronous tumors are most likely of a single appendiceal origin. Otherwise, they are more heterogeneous, and some may be truly dual primaries.

Serum and tissue markers in colorectal cancer: State of art

Colorectal cancer (CRC) represents one of the most commonly diagnosed cancers worldwide. It is the second leading cause of cancer death in Western Countries. In the last decade, the survival of patients with metastatic CRC has improved dramatically. Due to the advent of new drugs (irinotecan and oxaliplatin) and target therapies (i.e. bevacizumab, cetuximab, panitumab, aflibercept and regorafenib), the median overall survival has risen from about 12 mo in the mid nineties to 30 mo recently. Molecular studies have recently widened the opportunity for testing new possible markers, but actually, only few markers can be recommended for practical use in clinic. In the next future, the hope is to have a complete panel of clinical biomarkers to use in every setting of CRC disease, and at the same time: 1) to receive information about prognostic significance by their expression and 2) to be oriented in the choice of the adequate treatment. Moreover, molecular analyses have shown that the natural history of all CRCs is not the same. Individual patients with same stage tumors may have different long-term prognosis and response to therapy. In addition, some prognostic variables are likely to be more important than others. Here we review the role of serum and tissue markers according to the recently published English literature. This paper is an extension of the article "Biological and clinical markers in colorectal cancer: state of art" by Cappellani A published in Jan 2010.

Ovarian borderline tumors in the 2014 WHO classification: evolving concepts and diagnostic criteria

Borderline ovarian tumors (BOT) are uncommon but not rare epithelial ovarian neoplasms, intermediate between benign and malignant categories. Since BOT were first identified >40 years ago, they have inspired controversies disproportionate to their incidence. This review discusses diagnostic criteria for the histologic subtypes of BOT, highlighting areas of diagnostic challenges, ongoing controversies, and changes in terminology implemented by the recent 2014 WHO Classification of Tumours of the Female Genital Organs. Emerging knowledge supports the notion that subtypes of borderline ovarian tumors comprise distinct biologic, pathogenetic, and molecular entities, precluding a single unifying concept for BOT. Serous borderline tumors (SBT) share molecular and genetic alterations with low-grade serous carcinomas and can present at higher stages with peritoneal implants and/or lymph node involvement, which validates their borderline malignant potential. All other (non-serous) subtypes of BOT commonly present at stage I confined to the ovary(ies) and are associated with overall survival approaching that of the general population. An important change in the WHO 2014 classification is the new terminology of non-invasive implants associated with SBT, as any invasive foci (previously called “invasive implants”) are now in line with their biological behavior considered peritoneal low-grade serous carcinoma (LGSC). The controversy regarding the terminology of non-serous borderline tumors, called by some pathologists “atypical proliferative tumor” in view of their largely benign behavior, has not been resolved. The concepts of intraepithelial carcinoma and microinvasion may evolve in further studies, as their presence appears to have no prognostic impact and is subject to considerable inter-observer variability.

Synchronous Low-grade Appendiceal Mucinous Neoplasm and Primary Peritoneal Low-grade Serous Carcinoma: A First Description of These 2 Neoplasms Presenting Together as Suspected Peritoneal Carcinomatosis

Low-grade appendiceal mucinous neoplasm is a neoplasm typically of appendiceal origin, which is characterized by diffuse peritoneal involvement by pools of mucin with mucinous epithelium lacking high-grade cytologic atypia, and clinically presents as suspected peritoneal carcinomatosis. A similar clinical presentation can sometimes be seen with disseminated low-grade serous carcinomas of the peritoneum, fallopian tubes, or ovaries; however, this neoplasm is histologically characterized by tubal-type epithelium and invasive or confluent growth. In this case report, we describe a patient presenting with a clinical examination and radiologic features suggestive of peritoneal carcinomatosis and a prominent pelvic mass; however, after pathologic review, the patient was proven to have peritoneal involvement by both low-grade appendiceal mucinous neoplasm of appendiceal origin and a low-grade peritoneal primary serous carcinoma. In short, we present the first description of low-grade appendiceal mucinous neoplasm and serous carcinoma of the peritoneum presenting synchronously, providing morphologic characterization and immunohistochemical studies supporting the diagnosis, and illustrating a rare instance in which 2 neoplastic processes are underlying clinically suspected peritoneal carcinomatosis.

Efficacy of Immunohistochemical Staining in Differentiating a Squamous Cell Carcinoma in Poorly Differentiated Rectal Cancer: Two Case Reports

A rectal carcinoma, including primary an adenosquamous and a squamous cell carcinoma (SCC), is a very rare disease, accounting for 0.025% to 0.20% of all large-bowel malignant tumors. Because SCCs have a higher mortality than adenosquamous carcinomas, determining whether the primary rectal cancer exhibits an adenomatous component or a squamous component is important. While differentiating between these 2 components, especially in poorly differentiated rectal cancer, is difficult, specific immunohistochemical stains enable accurate diagnoses. Here, we report the use of immunohistochemical stains to distinguish between the adenomatous and the squamous components in 2 patients with low rectal cancer, a 58-year-old man and a 73-year-old woman, who were initially diagnosed using the histopathologic results for a poorly differentiated carcinoma. These data suggest that using these immunohistochemical stains will help to accurately diagnose the type of rectal cancer, especially for poorly differentiated carcinomas, and will provide important information to determine the proper treatment for the patient.