Endometriosis in a 22-Year-Old with Premature Ovarian Insufficiency Secondary to Pre-Pubertal Bone Marrow Transplant: a Case Report.

Endometriosis is often diagnosed in reproductive aged women with spontaneous ovarian activity. Here we described a case of endometriosis diagnosed in a patient with premature ovarian insufficiency (POI) due to prepubertal bone marrow transplant (BMT). The patient is a 22-year-old nulligravid female who presented with chronic pelvic pain. She had an inherited bone marrow failure syndrome (Diamond-Blackfan anemia), which required gonadotoxic chemotherapy for BMT at a young age prior to puberty. At age 13, she received hormone therapy with transdermal estrogen with subsequent addition of cyclic progestin and was later transitioned to combined oral contraceptive pills (COC). Endometriosis was suspected due to progressive dysmenorrhea and multiple cyclic systemic symptoms. She underwent a trial of elagolix, but could not tolerate it due to worsened arthralgia. Norethindrone acetate (NET-A) was then started, and she underwent diagnostic laparoscopy. Laparoscopy revealed scattered superficial endometriotic lesions in the pelvis. Histological studies showed florid endometriosis. Patient continues on NET-A 10mg and oral estradiol 0.5mg daily since the surgery and has experienced sustained improvement in her symptoms. Endometriosis should be considered as a possible cause for progressive dysmenorrhea or pelvic pain, even in the setting of POI. The balance between HT for overall health benefits in young women with POI and the risk of endometriosis exacerbation is delicate, but achievable.

Virtual Remote Pathology Education in Support of Virtual Remote Gynecologic-Oncology Training: The Open Pathology Education Network Pilot Proof of Concept Experience.

CONTEXT.­: The subspecialty workforce in pathology globally is inadequate for the demands of many modern therapies. The Open Pathology Education Network (OPEN) was formed to augment the global pathology workforce. The International Gynecologic Cancer Society (IGCS) virtual gynecologic-oncology (gyn-onc) fellowship training identified needs for higher-level pathology support. OBJECTIVE.­: To report on an OPEN-IGCS pilot project to support gyn-onc and pathology education efforts in a developing country. DESIGN.­: Curriculum with learning objectives and content from open sources was assembled. Mentoring sessions included bidirectional case sharing. Trainees received sequential curricula assignments and had options for communication outside mentoring sessions. Pretest and posttest digital slide assessments were included. Mentors attended the gynecology tumor board, allowing for the assessment of quality and accuracy of pathology diagnosis for cases discussed. RESULTS.­: Learners completing the pretest and posttest showed substantial improvement, with 2 practicing pathologists improving their diagnostic scores from 60% to an average of 95%. A third trainee-level participant also improved, but to a lesser degree. Qualitative assessments included increased confidence in presentation and an increased ability to anticipate questions, raise issues of expanded differential diagnoses, and articulate appropriate workup. Observations of clinicians who participated also noted increased confidence in participating pathologists. Secondary value included establishing an expanded network of support in other subspecialties for participants. Pathologic issues at the tumor board decreased, from more than 50% in the first 3 months of study to 0% in the last 3 months of study. The curriculum was embedded into a self-paced learning portal at courses.open-pathology.org. CONCLUSIONS.­: The OPEN-IGCS collaboration model shows the potential to provide subspecialty pathology training remotely.

The Malignant Potential of Ovarian Steroid Cell Tumors Revisited: A Multi-institutional Clinicopathologic Analysis of 115 Cases.

Steroid cell tumors (SCTs) of the ovary are rare and understudied, and as such, uncertainties remain about their malignant potential, as well as clinicopathologic predictors of patient outcome. Based on a multi-institutional cohort of cases, we present findings from the largest study of SCT reported to date. Clinicopathologic data were documented on 115 cases of SCT that were assembled from 17 institutions. The median patient age was 55 years (range: 9 to 84). When measured, preoperative androgen levels were elevated in 84.2% (48/57) of patients. A total of 111 (96.5%) cases were classified as stage I (103 stage IA; 2 stage IB; 6 stage IC). The stage distribution for the remaining 4 patients was as follows: stage II (n = 1), III (n = 3; 1 IIIA, 1 IIIB, 1 IIIC). The median tumor size was 3 cm (range: 0.2 to 22). Cytologic atypia, microscopic tumor necrosis, microscopic tumor hemorrhage, and a mitotic index of >1 mitotic figure/10 high-power fields were present in 52% (60/115), 9.6% (11/115), 37% (43/115), and 19% (22/115) of cases, respectively. Of 115 patients, 7 (6.1%) recurred postexcision, 4 (3.5%) ultimately died of disease, and 10 (8.7%) either recurred, died of disease, or were advanced stage at presentation. The median duration to recurrence postresection was 33 months (range: 23 to 180). Four of the 7 recurrences were stage IA at baseline. Tumor size >4 cm, International Federation of Gynecology and Obstetrics (FIGO) stage ≥IB, tumor necrosis, and tumor hemorrhage were each significantly associated with reduced recurrence-free survival in log-rank tests and univariable Cox models, with age older than 65 years being of marginal significance (hazard ratio [HR]: 5.4, 95% CI: 1.0-30.0, P = 0.05). Multivariable analyses suggested that FIGO stage ≥IB (HR: 27.5, 95% CI: 2.6-290.5), and age older than >65 years (HR: 21.8, 95% CI: 1.6-303.9) were the only parameters that were independently associated with recurrence. Cross-section analyses showed that tumor necrosis, tumor hemorrhage, and larger tumor size were significantly associated with a FIGO stage ≥IB status, which bolstered the conclusion that they are not independent predictors of recurrence. In summary, <10% of SCTs are clinically malignant, a substantially lower frequency than has previously been reported in the literature. Clinicopathologic predictors of patient outcomes that are prospectively applicable in practice could not be definitively established. Recurrences may occur many years (up to 15 y in this study) after primary resection, even in stage IA cases.

Recent Advances in Genitourinary Tumors Updates From the 5th Edition of the World Health Organization Blue Book Series.

CONTEXT.­: Urinary and Male Genital Tumours is the 8th volume of the World Health Organization Classification of Tumours series, 5th edition. Released in hard copy in September 2022, it presents an update to the classification of male genital and urinary tumors in the molecular age. Building upon previous volumes in this series, significant effort has been made to harmonize terminology across organ systems for biologically similar tumors (eg, neuroendocrine tumors). Genomic terminology has been standardized and genetic syndromes covered more comprehensively. This review presents a concise summary of this volume highlighting new entities, notable modifications relative to the 4th edition, and elements of relevance to routine clinical practice. OBJECTIVE.­: To provide a comprehensive update on the World Health Organization classification of urinary and male genital tumors, highlighting updated diagnostic criteria and terminology. DATA SOURCES.­: The 4th and 5th editions of the World Health Organization Classification of Tumours: Urinary and Male Genital Tumours. CONCLUSIONS.­: The World Health Organization has made several changes in the 5th edition of the update on urinary and male genital tumors that pathologists need to be aware of for up-to-date clinical practice.

Recent Advances in the Classification of Gynecological Tract Tumors: Updates From the 5th Edition of the World Health Organization "Blue Book".

CONTEXT.­: The World Health Organization Classification of Tumours: Female Genital Tract Tumors, 5th edition, published in September 2020, comes 6 years after the 4th edition, and reflects the monumental leaps made in knowledge about the biology of gynecological tumors. Major changes include revised criteria for the assignment of the site of origin of ovarian and fallopian tube tumors, a revision in the classification of squamous and glandular lesions of the lower genital tract based on human papillomavirus association, and an entire chapter devoted to genetic tumor syndromes. This article highlights the changes in the 5th edition relative to the 4th edition, with a focus on areas of value to routine clinical practice. OBJECTIVE.­: To provide a comprehensive update on the World Health Organization classification of gynecological tumors, highlighting in particular updated diagnostic criteria and terminology. DATA SOURCES.­: The 4th and 5th editions of the World Health Organization Classification of Tumours. CONCLUSIONS.­: The World Health Organization has made several changes in the 5th edition of the update on female genital tumors. Awareness of the changes is needed for pathologists' translation into contemporary practice.

Cervical Pleuropulmonary Blastoma-like Tumor Associated With DICER1 and TP53 Mutations.

We describe a very unusual cervical tumor in a 12-yr-old patient with a clinical history indicative of DICER1 syndrome. Morphologic, immunohistochemical, and molecular genetic analysis together helped to diagnose this lesion as a cervical pleuropulmonary blastoma-like tumor, associated with TP53 and DICER1 mutations. The tumor displayed usual histologic features including mixtures of embryonal rhabdomyosarcoma, sarcomatous cartilage, compact blastema, primitive spindle cells and anaplasia, akin to type III pleuropulmonary blastoma, and trabecular and retiform patterns. In addition to expanding the phenotypic spectrum of DICER1 -associated conditions, we draw attention to genotype-phenotype correlations in DICER1 -associated tumors, particularly as they relate to the discovery of a heritable tumor predisposition syndrome.

Endometrial Carcinoma as the Presenting Malignancy in a Teenager With a Pathogenic TP53 Germline Mutation: A Case Report and Literature Review.

Patients with germline TP53 mutations are characterized by the occurrence of multiple early-onset malignancies. The characteristic syndrome is Li-Fraumeni syndrome (OMIM # 151623), an autosomal dominant disorder typified by premenopausal breast carcinoma, adrenal cortical tumors, bone and soft tissue sarcomas, leukemias, and tumors of the brain and spinal cord. Gynecologic malignancies are uncommonly reported in families harboring TP53 mutations, and the predominant tumor type reported is ovarian. Uterine carcinoma has been reported only a handful of times in patients with germline TP53 mutations, none as a presenting tumor in a teenager. We report on an 18-year-old patient who presented with grade 3, high-stage endometrioid endometrial carcinoma. Sequencing detected a single-nucleotide substitution in the TP53 gene (NM_000546.6:c.818G>A), encoding the missense substitution p.Arg273His (R273H) in both the tumor and normal tissue, consistent with a germline mutation. We discuss the biology of the TP53 gene and p53 protein, with emphasis on the R273H mutation. We also review the literature on endometrial carcinoma in patients with germline TP53 mutations.

Addressing quality and safety in anatomic pathology in low- and middle-income countries.

The World Health Organization (WHO) has created a sustainable development goal of reducing preventable mortality from cancer in low- and middle-income countries (LMICs) by 30% by 2030. Central to achieving this goal is the creation and maintenance of quality anatomic pathology services (APS). Within the last decade, quality assurance programs and patient safety measures have become a major focus of research for upper middle- and high-income countries (UMHICs), which has led to marked documented improvement in the quality of services provided by laboratories, as well as a decrease in patient safety events. We propose that as APS are developed in LMICs, the lessons learned by UMHICs are necessary to incorporate to produce quality and safe services toward obtaining the aforementioned goal. Furthermore, data suggests that Quality Improvement work requires change at the macrosystems and microsystems levels to achieve these goals. Here, we propose five "microsystems" strategies for professional organizations, healthcare institutions in LMICs and UMHICs that would accelerate quality improvement programs/systems implementation in APS in LMICs.

Chronic endometritis: A prevalent yet poorly understood entity.

OBJECTIVE: To examine the prevalent understanding of and management approaches to chronic endometritis among obstetricians/gynecologists. METHODS: In a cross-sectional observational study, 262 members of national and international professional obstetrician/gynecologist societies were surveyed via anonymous electronic survey that investigated knowledge of the pathophysiology, diagnostic criteria, clinical implications, and treatment strategies for chronic endometritis. Statistical analyses of results were performed using Fisher's exact tests, chi square tests and odds ratios with 95% confidence intervals. A two-sided P < 0.05 was deemed statistically significant. RESULTS: Responses identified a concerning spectrum of deficiencies in the understanding of the pathophysiology of chronic endometritis, in awareness of clinical presentation of chronic endometritis, and in the understanding of methodology/ies that allow diagnosis of chronic endometritis. Heterogeneities in management approaches to chronic endometritis were apparent. CONCLUSION: Our findings underscore a need for targeted efforts to gain clarity on chronic endometritis and to establish evidence-based consensus for good clinical practice. In the absence of a clear understanding of chronic endometritis diagnosis, we posit that the prevalent inconsistencies are likely inflicting unquantified and underappreciated burdens on patients and healthcare systems. We propose consideration for a task force to examine existing literature and create standards for good practice for a prevalent condition.

Mixed Endometrioid Adenocarcinoma and Müllerian Adenosarcoma of the Uterus and Ovary: Clinicopathologic Characterization With Emphasis on its Distinction From Carcinosarcoma.

Mullerian adenosarcoma is a biphasic neoplasm composed of benign or atypical Müllerian epithelium and a malignant mesenchymal component that is usually, but not always, of low grade. Focal architectural or cytologic atypia of the epithelial component resembling atypical hyperplasia may uncommonly be present and foci of adenocarcinoma have been rarely reported. Whether the coexistence of these 2 tumor components is a result of independent primaries (collision tumor), adenocarcinoma arising from the epithelial component of the adenosarcoma, an unusual form of carcinosarcoma or some other mechanism is uncertain. To establish the diagnostic criteria and clinical significance of the coexistence of adenocarcinoma in close association with Müllerian adenosarcoma, we conducted a multi-institutional study of these rare tumors. Twenty-six patients were identified with "mixed" adenosarcoma and adenocarcinoma; they ranged in age from 43 to 87 years (median: 66 y). Tumors occurred in the uterine corpus (n=22), ovary (n=2), and the pelvis (n=2). All but 6 had International Federation of Gynecology and Obstetrics (FIGO) stage I disease. All extrauterine tumors were associated with endometriosis. The tumor size ranged from 2 to 25 cm (median: 7.9 cm). The sarcomatous component was of low grade in 18 and high grade in 8 (the majority demonstrating rhabdomyoblastic differentiation); 9 had stromal overgrowth. Twenty-five carcinomas were endometrioid in type (23 FIGO grade 1; 3 FIGO grade 2) and 1 carcinoma was dedifferentiated with FIGO grade 1 endometrioid adenocarcinoma component; 33% of the uterine neoplasms were associated with adjacent endometrial hyperplasia. Next-generation sequencing in 2 tumors identified similar molecular abnormalities in the sarcomatous and carcinomatous components supporting a clonal relationship. Of 10 patients with available follow-up (median: 18 mo), 8 had no evidence of disease and 2 died of recurrent sarcoma at 7 and 8 months. Endometrioid adenocarcinomas that arise in close spatial association with Müllerian adenosarcoma appear to be clonally related to the sarcoma. Unlike carcinosarcomas, these tumors are usually early stage at presentation. The prognosis appears to be driven by the sarcomatous component. These tumors should be distinguished from carcinosarcomas, dedifferentiated endometrial carcinomas, and corded and hyalinized endometrioid carcinomas.

The Diagnostic Criteria for Chronic Endometritis: A Survey of Pathologists.

While acute endometritis is a reasonably well-defined entity of ascending infection and attendant active inflammation, chronic endometritis is less well defined. As part of a broad effort to define and refine the diagnostic criteria and management of the disease, we conducted a survey of pathologists to understand the variability in diagnostic criteria and implications of the diagnosis of nonspecific, nonobstetric chronic endometritis. Members of national and international professional pathology societies were surveyed utilizing anonymous electronic surveys designed to examine diagnostic criteria, etiological understanding and treatment implications of a pathologic diagnosis of nonspecific, nonobstetric chronic endometritis. There was substantial variability among pathologists in the diagnostic criteria used for making a diagnosis of nonspecific, nonobstetric chronic endometritis, with 28.5% of pathologists using the presence of a single plasma cell for making the diagnosis. There was additional variability in the use of special stains, reporting in the presence of coexisting lesions and the hormonal stage of the endometrium. There were no differences between generalists and specialists in the diagnostic criteria used, except the significantly greater likelihood of specialists making the diagnosis in gestational endometrium. The substantial variability in diagnostic criteria for nonspecific, nonobstetric chronic endometritis among pathologists, including among gynecologic pathologists, has the potential to confound the management of patients. Standardization of diagnostic criteria for chronic endometritis is essential to understand the implications of the diagnosis.

Omental macrophages secrete chemokine ligands that promote ovarian cancer colonization of the omentum via CCR1.

The omentum is the most common site of ovarian cancer metastasis. Immune cell clusters called milky spots are found throughout the omentum. It is however unknown if these immune cells contribute to ovarian cancer metastasis. Here we report that omental macrophages promote the migration and colonization of ovarian cancer cells to the omentum through the secretion of chemokine ligands that interact with chemokine receptor 1 (CCR1). We found that depletion of macrophages reduces ovarian cancer colonization of the omentum. RNA-sequencing of macrophages isolated from mouse omentum and mesenteric adipose tissue revealed a specific enrichment of chemokine ligand CCL6 in omental macrophages. CCL6 and the human homolog CCL23 were both necessary and sufficient to promote ovarian cancer migration by activating ERK1/2 and PI3K pathways. Importantly, inhibition of CCR1 reduced ovarian cancer colonization. These findings demonstrate a critical mechanism of omental macrophage induced colonization by ovarian cancer cells via CCR1 signaling.

Reproducibility of AJCC Criteria for Classifying Deeply Invasive Colon Cancers Is Suboptimal for Consistent Cancer Staging.

The eighth edition of the American Joint Committee on Cancer (AJCC) Staging Manual attempts to address ambiguity in the pT category assignment for colon cancer from prior editions. Despite modifications, the distinction between the pT3 and pT4a categories continues to be a source of diagnostic confusion. In this study, we assessed interobserver agreement among pathologists from different institutions in the application of AJCC eighth edition criteria for categorizing deeply invasive colonic adenocarcinomas. We identified morphologic patterns that produce diagnostic confusion. We assessed 47 colon cancers that closely approached the serosal surface. Six pathologists with interest in gastrointestinal pathology and 4 focused in other subspecialties classified each case as pT3 or pT4a, based on examination of low-magnification and high-magnification images of the most deeply invasive area. Interobserver agreement was assessed using Fleiss' κ. Cases displayed 3 morphologic patterns at the advancing tumor edge, namely, (1) continuous invasion through an inflammatory focus, (2) pushing border, and (3) infiltrative glands and cell clusters with serosal reaction. Gastrointestinal pathologists achieved slight (κ=0.21) or moderate (κ=0.46) and (κ=0.51) agreement in each category, whereas agreement among nongastrointestinal pathologist was fair (0.31) and (0.39), or moderate (0.57) for each category, respectively. In 10 (21%) cases, the distinction between pT3 and pT4a would have changed the overall clinical stage. We conclude that histologic criteria for serosal penetration is a persistent source of diagnostic ambiguity for gastrointestinal and general pathologists in the pT categorization of colon cancers. Clarification of these criteria will help ensure uniform reporting of pathologic and clinical stage.

Endometrial tumors with yolk sac tumor-like morphologic patterns or immunophenotypes: an expanded appraisal.

Uterine yolk sac tumors have gained increased recognition in recent years. The current study is a multi-faceted examination of yolk sac tumor-like phenotypes in endometrial tumors, based on an analysis of 3 groups of uterine tumors: Group 1: 9 endometrial tumors that had been classified as yolk sac tumor, or as having a yolk sac tumor component, were assessed with a 35-marker immunohistochemical panel, with the goal of defining their immunophenotypic spectrum; Group 2, comprised of 70 endometrial carcinomas of various histotypes, were analyzed for their expression of SALL4, Glypican-3, and AFP, to assess the specificity of these markers for yolk sac tumors relative to endometrial carcinomas; Group 3, comprised of 626 archived cases of endometrial carcinoma/carcinosarcoma, reviewed to define the frequency of yolk sac tumor-like morphology therein. Yolk sac tumor areas in the Group 1 cases were consistently immunoreactive for SALL4 and Glypican-3; variably positive for AFP (89%), Villin (89%), PLAP (78%), 34ßE12 (67%), CAM 5.2 (62.5%), EMA (56%), CD117 (50%), p16 (50%), CDX2 (44%), p53 (44% aberrant), MOC31 (37.5%), CK7 (33%), GATA3 (33%), CK5 (25%), and PAX8 (11%); and were negative for CD30, Napsin A, OCT4, estrogen, androgen, and progesterone receptors. 29 (41%) of the 70 group-2 cases expressed at least one of the 3 markers, and 96% of the positive cases was a high-grade histotype. Glypican-3, SALL4, and AFP were positive in 30, 20, and 2.8% of group-2 cases respectively; however, co-expression of any 2, or all 3 markers was uncommon (<9 and 1.4% of cases respectively). Potential yolk sac tumor-like morphology was identified in 5 (0.8%) of 626 group-3 cases, and three were ultimately deemed to be true yolk sac tumor phenotypes based on their morphologic and immunophenotypic similarity to the group 1 cases. These findings highlight the broad immunophenotypic spectrum of uterine yolk sac tumors, the potential pitfalls associated with using immunophenotypes alone to define yolk sac tumor differentiation in endometrial carcinoma, and the utility and limitations of morphologic assessment to identify yolk sac tumors at this site.

Pseudovascular Invasion: Minimally Invasive Surgery for Endometrial Cancer.

BACKGROUND AND OBJECTIVES: To determine if the use of an intrauterine manipulator is associated with an increased incidence of pseudovascular invasion on pathologic evaluation of hysterectomy specimens for endometrial cancer and to assess the possible implications of pseudovascular space invasion in the treatment of endometrial cancer. METHODS: We performed a retrospective cohort study of patients with early stage (I/II) endometrial cancer who underwent minimally invasive surgical staging. The following data were abstracted: race, body mass index, grade, age, stage, histology, presence or absence of lymphovascular space invasion (LVSI), peritoneal cytology, and adjuvant treatment. Slides were blindly reviewed by a gynecologic pathologist. RESULTS: Of the104 patients meeting eligibility criteria, 74 cases were reviewed in detail (the study was terminated early based on the results of an interim analysis). Patients in the no-manipulator group were older (P = .02) and had a higher stage 1B/II (P = .01) than patients in the manipulator group. No difference was found in the incidence of pseudovascular invasion between the manipulator and the no-manipulator groups (P = .86). Subgroup analysis showed no association of pseudovascular invasion with tumor grade (P = .79). Five patients were identified to have pseudovascular invasion misdiagnosed as true LVSI-4 had endometrioid and 1 had serous histology. Of these, 3 were in the manipulator group. Two received adjuvant radiotherapy which they not have gotten, absent reported lymphovascular invasion. CONCLUSION: The use of a uterine manipulator does not appear to increase the rate of pseudovascular invasion in our limited data set. Misdiagnosis of pseudovascular invasion as LVSI can result in risk migration of patients with potential for harm from unwarranted adjuvant therapy.

Endometrial Carcinoma: Grossing, Frozen Section Evaluation, Staging, and Sentinel Lymph Node Evaluation.

This article gives an overview of the pathologic assessment of resection specimens removed for uterine carcinoma. Areas of controversy and recent developments in pathologic staging are addressed. This includes assessment of myometrial invasion in the setting of adenomyosis, fallopian tube involvement, and vascular invasion. An overview of the role and evaluation of sentinel node assessments in the staging of endometrial carcinoma is provided.

Pathology of Endometrioid and Clear Cell Carcinoma of the Ovary.

This review is an appraisal of the current state of knowledge of 2 enigmatic histotypes of ovarian carcinoma: endometrioid and clear cell carcinoma. Both show an association endometriosis and the hereditary nonpolyposis colorectal cancer (Lynch) syndrome, and both typically present at an early stage. Pathologic and immunohistochemical features that distinguish these tumors from high-grade serous carcinomas, each other, and other potential mimics are discussed, as are staging, grading, and molecular pathogenesis.

The Spectrum of Morphologic Alterations Associated With Infarction in Endometrial Polyps: A Report of 41 Cases.

The authors describe the clinicopathologic features of a group of endometrial polyps that exhibited large areas of infarction, to highlight the spectrum of morphologic alterations that may occur in this setting, including moderate cytologic atypia in a subset. Forty-one infarcted endometrial polyps, classified as such based on the presence therein of confluent zones of stromal necrosis and/or sharply demarcated zones of paucicellular to acellular stromal hyalinization, were assembled from multiple institutions. All were diagnosed in biopsies, polypectomies, or curettages. The morphologic profile of the epithelium associated with the infarcted zones was compared with those of a control group of 40 consecutive noninfarcted polyps. The patients with infarcted polyps ranged in age from 23 to 94 yr and were significantly older than the control group patients (mean ages, 60.8 vs. 49 yr respectively; P=0.02). The most common architectural alteration in infarcted polyps was a distinctive cellular tufting or pseudopapillary change, possibly representing an exuberant iteration of papillary syncytial change, which was seen in 39% of cases. Among the features that were significantly more prevalent in infarcted polyps than the control group were grade 2 pleomorphism (i.e., a 2-3-fold variation in nuclear size and/or shape) (37% vs. 2.5%, respectively; P=0.00029), cellular syncytia (44% vs. 15%; P=0.069), vesicular chromatin greater than background glands (56% vs. 7.5%; P <0.0001), hobnail cells (27% vs. 0%; P=0.0004), clear cells (12% vs. 0%; P=0.055), and eosinophilic cells (56% vs. 15%; P=0.000115). The 2 groups were not significantly different regarding mitotic index and a variety of other morphologic variables. Irrespective of morphology, epithelia within the infarcted zones at least focally showed a core immunophenotype (p53-wild type, p16-diffusely positive; low proliferative index) that was essentially identical to the phenotype displayed by foci of papillary syncytial metaplasia unassociated with polyps in a 10-case comparison group. None of the 34 patients with follow-up information has subsequently been diagnosed with a uterine neoplasm. In summary, infarcted endometrial polyps frequently display a spectrum of cytoarchitecturally atypical epithelial changes. These pseudoneoplastic alterations are most likely degenerative and/or metaplastic in nature.

International Society of Gynecological Pathologists (ISGyP) Endometrial Cancer Project: Guidelines From the Special Techniques and Ancillary Studies Group.

The aim of this article is to propose guidelines and recommendations in problematic areas in pathologic reporting of endometrial carcinoma (EC) regarding special techniques and ancillary studies. An organizing committee designed a comprehensive survey with different questions related to pathologic features, diagnosis, and prognosis of EC that was sent to all members of the International Society of Gynecological Pathologists. The special techniques/ancillary studies group received 4 different questions to be addressed. Five members of the group reviewed the literature and came up with recommendations and an accompanying text which were discussed and agreed upon by all members of the group. Twelve different recommendations are made. They address the value of immunohistochemistry, ploidy, and molecular analysis for assessing prognosis in EC, the value of steroid hormone receptor analysis to predict response to hormone therapy, and parameters regarding applying immunohistochemistry and molecular tests for assessing mismatch deficiency in EC.

Current Practices in the Processing, Diagnosis, and Reporting of Endometrial Carcinoma: Results of a Web-based Survey by the International Society of Gynecological Pathologists (ISGyP).

There have been significant advances in our understanding of the biology and classification of endometrial carcinoma, over the last few years, and the new prediction models proposed for prognostication. To accurately diagnose and stage tumors and apply these prediction models, it is necessary that there be standardized processing of specimens, and a common understanding and usage of the diagnostic terminology of endometrial carcinoma. The International Society of Gynecological Pathologists embarked on an ambitious project to achieve this goal in 2015. An early step in the process was to collect baseline information on existing practices with regard to the processing, diagnosis, and reporting of endometrial carcinomas among the members of the society. This was carried out using a web-based survey comprising 112 questions. The results are presented herein and reveal areas of uniformity but also areas of substantial variation among pathologists. The results of the survey assisted in developing the subsequent recommendations that follow as separate articles in this issue of the journal with regard to processing, diagnosis, and reporting of endometrial carcinomas.