Ovarian Sex Cord-Stromal Neoplasms: An Overview of Molecular Events and How to Correlate Morphology With Molecular Findings.

Since the discovery in 2009 that missence pathogenic variants/mutations in FOXL2 are extremely common in ovarian adult granulosa cell tumours, the last 2 decades have witnessed significant developments in our understanding of the molecular events underlying the pathogenesis of other ovarian sex cord-stromal tumours (SCSTs). In this review, we cover the molecular events in ovarian SCSTs and provide practical guidance to the reporting pathologist as to how and when molecular testing may be useful in diagnosis. We stress the need to correlate the morphology and molecular since most of the molecular events are not entirely specific for a particular tumour type and our knowledge is continually evolving with the elucidation of "new" molecular events. We also discuss that in some tumours, molecular testing is helpful in triaging the patient for genetic referral and germline testing since some of the molecular events may be germline in nature.

Assessing the impact of deep-learning assistance on the histopathological diagnosis of serous tubal intraepithelial carcinoma (STIC) in fallopian tubes.

In recent years, it has become clear that artificial intelligence (AI) models can achieve high accuracy in specific pathology-related tasks. An example is our deep-learning model, designed to automatically detect serous tubal intraepithelial carcinoma (STIC), the precursor lesion to high-grade serous ovarian carcinoma, found in the fallopian tube. However, the standalone performance of a model is insufficient to determine its value in the diagnostic setting. To evaluate the impact of the use of this model on pathologists' performance, we set up a fully crossed multireader, multicase study, in which 26 participants, from 11 countries, reviewed 100 digitalized H&E-stained slides of fallopian tubes (30 cases/70 controls) with and without AI assistance, with a washout period between the sessions. We evaluated the effect of the deep-learning model on accuracy, slide review time and (subjectively perceived) diagnostic certainty, using mixed-models analysis. With AI assistance, we found a significant increase in accuracy (p < 0.01) whereby the average sensitivity increased from 82% to 93%. Further, there was a significant 44 s (32%) reduction in slide review time (p < 0.01). The level of certainty that the participants felt versus their own assessment also significantly increased, by 0.24 on a 10-point scale (p < 0.01). In conclusion, we found that, in a diverse group of pathologists and pathology residents, AI support resulted in a significant improvement in the accuracy of STIC diagnosis and was coupled with a substantial reduction in slide review time. This model has the potential to provide meaningful support to pathologists in the diagnosis of STIC, ultimately streamlining and optimizing the overall diagnostic process.

Diagnostic Utility of Deeper Level Tissue Sections of Negative Peritoneal Biopsies for Clinically Suspected Endometriosis.

Definitive diagnosis of endometriosis is established by histologic confirmation in tissue from surgically visualized lesions; however, the diagnostic sensitivity of this approach varies widely. We hypothesized that incomplete tissue block sampling may contribute to false-negative diagnosis, particularly if the focus of endometriosis in the tissue section is scant. This study defined the diagnostic value of deeper level tissue sections in cases in which none of the specimen parts contained endometriosis on the initial tissue sections, using the World Health Organization essential criteria for diagnosis of endometriosis (presence of endometrial glands and endometrial stroma). Among 135 patients who underwent surgery for suspected endometriosis by a single surgeon at an academic institution from 2015 to 2019, the initial tissue sections resulted in a diagnosis of endometriosis in 73.3% (99/135), at an average diagnostic yield of 5.9 slides per diagnosis of endometriosis. An additional 9 patients were diagnosed with endometriosis by deeper level tissue sections, increasing the diagnostic rate to 80% (108/135). This 6.7% gain in the diagnostic rate came at an increase in resource utilization, with an overall overage diagnostic yield of 9.8 slides per diagnosis of endometriosis. Overall, 8.3% of patients had a false-negative diagnosis on the initial tissue sections. When extrapolated to a population level, the number of patients potentially affected by this source of false-negative diagnosis and the implications for patients merit consideration of the use of deeper level sections if none of the initial sections of any of the specimens contains endometriosis.

Radiology State-of-the-art Review: Endometriosis Imaging Interpretation and Reporting.

Endometriosis is a common condition impacting approximately 190 million individuals and up to 50% of women with infertility globally. The disease is characterized by endometrial-like tissue located outside of the uterine corpus, which causes cyclical hemorrhage, inflammation, and fibrosis. Based on clinical suspicion or findings at routine transvaginal pelvic US or other prior imaging, dedicated imaging for endometriosis may be warranted with MRI or advanced transvaginal US. Deep endometriosis (DE) in the pelvis includes evaluation for stromal and fibrotic components and architectural distortion resulting from fibrosis and tethering. It is a disease requiring a compartment-based, pattern-recognition approach. MRI has the benefit of global assessment of the pelvis and is effective in assessing for features of malignancy and for evaluating extrapelvic locations. Transvaginal US has the advantage of dynamic maneuvers to assess for adhesions and may achieve higher spatial resolution for assessing the depth of bowel wall invasion. T1-weighted MRI evaluation increases the specificity of diagnosis by identifying hemorrhagic components, but the presence of T1 signal hyperintensity is not essential for diagnosing DE. Endometriosis is a disease with a broad spectrum; understanding the mild through advanced manifestations, including malignancy evaluation, is within the scope and breadth of radiologists' interpretation.

Improved Risk Prediction in Human Papillomavirus-Associated Endocervical Adenocarcinoma Through Assessment of Binary Silva Pattern-based Classification: An International Multicenter Retrospective Observational Study Led by the International Society of Gynecological Pathologists (ISGyP).

Endocervical adenocarcinomas (EACs) are a group of malignant neoplasms associated with diverse pathogenesis, morphology, and clinical behavior. As a component of the International Society of Gynecological Pathologists International Endocervical Adenocarcinoma Project, a large international retrospective cohort of EACs was generated in an effort to study potential clinicopathological features with prognostic significance that may guide treatment in these patients. In this study, we endeavored to develop a robust human papillomavirus (HPV)-associated EAC prognostic model for surgically treated International Federation of Gynecology and Obstetrics (FIGO) stage IA2 to IB3 adenocarcinomas incorporating patient age, lymphovascular space invasion (LVSI) status, FIGO stage, and pattern of invasion according to the Silva system (traditionally a 3-tier system). Recently, a 2-tier/binary Silva pattern of invasion system has been proposed whereby adenocarcinomas are classified into low-risk (pattern A/pattern B without LVSI) and high-risk (pattern B with LVSI/pattern C) categories. Our cohort comprised 792 patients with HPV-associated EAC. Multivariate analysis showed that a binary Silva pattern of invasion classification was associated with recurrence-free and disease-specific survival (P < 0.05) whereas FIGO 2018 stage I substages were not. Evaluation of the current 3-tiered system showed that disease-specific survival for those patients with pattern B tumors did not significantly differ from that for those patients with pattern C tumors, in contrast to that for those patients with pattern A tumors. These findings underscore the need for prospective studies to further investigate the prognostic significance of stage I HPV-associated EAC substaging and the inclusion of the binary Silva pattern of invasion classification (which includes LVSI status) as a component of treatment recommendations.

Prevalence of Occult Ovarian Cancer and Metastatic Breast Cancer in Ovarian Ablation Specimens of Patients With Hormone Receptor-Positive Breast Cancer: Implications for Tissue Sampling Strategies, Early Ovarian Cancer Detection and Resource Utilization.

Bilateral oophorectomy is one method of hormone suppression for premenopausal patients with hormone receptor-positive breast cancer. Such specimens could, in theory, harbor occult early ovarian cancer and/or metastatic breast cancer but guidelines for tissue sampling for pathologic examination remain to be addressed. Therefore, we evaluated oophorectomy specimens from 166 patients who underwent ovarian ablation for hormone receptor-positive breast cancer. Results of germline genetic testing were documented by the surgeon in only 31.3% of the pathology specimen requisition forms, whereas that information was available for 81.3% of patients elsewhere in the electronic medical records. All but 5.2% tested negative for a hereditary ovarian cancer gene pathogenic variant before oophorectomy. Complete tissue sampling was performed in 77.1% of the cases and representative sampling in the remainder. No cases of ovarian cancer were observed. Ovarian metastasis of breast cancer was identified in 9.6% of patients, all of whom were already known to have advanced-stage disease. The number of tissue cassettes per ovary required for complete tissue submission was on average three times higher than that for representative tissue sampling (P < 0.01) and ranged up to 20 cassettes per ovary when multiple follicle cysts were present. We propose that guidelines for tissue sampling in this context be defined by a combination of hereditary risk and macroscopic examination; representative sampling is reasonable for macroscopically normal ovaries in hormone receptor-positive breast cancer patients whose germline genetic testing is negative. Positive genetic test results merit complete tissue submission even if macroscopically normal. This strategy balances the goals of early ovarian cancer detection and optimal resource utilization. However, it depends on clear documentation of genetic test results. Our study demonstrates that many opportunities remain to close gaps in the communication of genetic test results by clinicians submitting oophorectomy specimens for pathologic evaluation.

Perceptions of Controversies and Unresolved Issues in the 2014 FIGO Staging System for Endometrial Cancer: Survey Results From Members of the International Society of Gynecological Pathologists and International Gynecologic Cancer Society.

Long-standing controversial and unresolved issues in the current "International Federation of Gynecology and Obstetrics" staging system for endometrial cancer are well-recognized by pathologists and clinicians alike and exist primarily as a result of limitations to the existing literature. To guide the design of future outcome-based studies specifically aimed at resolving such gaps, the International Society of Gynecologic Pathologists developed a survey of the current perceptions of pathologists (n = 172) and clinicians (n= 135) from the International Society of Gynecological Pathologists and from the International Gynecologic Cancer Society on areas for potential refinement of the current International Federation of Gynecology and Obstetrics staging system. The highest priority issues for pathologists and clinicians alike were the need to determine whether stage IIIA patients (ovarian/fallopian tube involvement) can be reliably separated into favorable versus unfavorable outcome groups to avoid over-treatment of the former group and to determine whether stage IIIC patients (lymph node metastases) can be separated into favorable versus unfavorable outcome groups based on the size of lymph node metastases. The majority of pathologists and clinicians viewed lymphovascular space invasion as an independent prognostic variable and favored incorporating lymphovascular space invasion into staging, though the level of support did not meet the threshold of 75% in support that we used to define a formal consensus. While pathologists did agree on the prognostic value of reporting the extent of lymphovascular space invasion, there was no consensus on the diagnostic criteria to distinguish focal versus substantial involvement. The majority of pathologists and clinicians viewed that a universally accepted protocol for sentinel lymph node ultra-staging is lacking. Both survey groups conveyed a slight preference for incorporating tumor histotype and molecular classification into staging but the support was short of the 75% threshold for formal consensus. Collectively, this survey permits the International Society of Gynecological Pathologists to develop a pathologist and clinician-driven long-term strategy for prioritizing and designing outcome-based studies specifically targeted to resolving controversial and unresolved issues in the International Federation of Gynecology and Obstetrics staging of endometrial cancer.

FIGO 2023 endometrial cancer staging: too much, too soon?

An updated International Federation of Gynecology and Obstetrics (FIGO) staging system for endometrial carcinoma was introduced in June 2023. The new system represents a significant departure from traditional endometrial and other gynecological carcinoma staging systems which are agnostic of parameters such as tumor type, tumor grade, lymphovascular space invasion, and molecular alterations. The updated system, which incorporates all of these 'non-anatomical' parameters, is an attempt to make staging more personalized and relevant to patient prognostication and management, and to align with the European Society of Gynaecological Oncology/European Society for Radiotherapy and Oncology/European Society of Pathology (ESGO/ESTRO/ESP) risk stratification. Herein, we present a critical review of the new staging system and discuss its advantages and disadvantages. The authors propose that the new FIGO staging system should be first appraised at a multi-institutional and global level with the input of all relevant societies (gynecology, pathology, gynecologic oncology, medical oncology, radiation oncology) to understand the impact, scope, and supporting evidence of the proposed changes. Such a process is fundamental to produce a robust system that pathologists and treating clinicians can adopt.

Intact Chorionic Vesicle in Very Early Products of Conception Specimens: Clinicopathologic Features of 26 Cases That May Mimic Complete Hydatidiform Mole.

Among the morphologic mimics of hydatidiform moles, the chorionic vesicle of early first-trimester pregnancy has received scant attention. The chorionic vesicle is the stage of the implanted blastocyst in which the cytotrophoblastic shell is circumferentially lined by primary and secondary villi and envelops the notochord stage embryo, yolk sac, and amniotic sac, ∼5 to 6 weeks since the last menstrual period. Miscarriage specimens at this early gestational age that contain an intact chorionic vesicle may be misinterpreted as a complete hydatidiform mole because of its large size, cistern-like cavity, and circumferentially radiating villi and trophoblast, particularly so when embryonic tissue is absent. We present the clinicopathologic features of 26 products of conception specimens containing a chorionic vesicle, some of which were submitted for consultation as a possible complete mole. The median gestational age was 6 weeks. The majority were free-floating in the specimen, unattached to endometrium. The median diameter was 6.3 mm and ranged up to 11.3 mm. The embryo was absent in 81% of cases, leaving an empty cavity resembling the cistern of a complete mole in all but 2 cases. Most cases exhibited circumferential villi and variable degrees of proliferating polarized villous trophoblast and extravillous trophoblast but trophoblast atypia was absent. Villous stromal karyorrhexis and blue-gray myxoid extracellular stromal matrix were observed in the majority of cases. A minority exhibited focal abnormal villous morphology concerning for early molar pregnancy, including irregular projections (27%), invaginations (12%), or bulbous shapes (4%) of the villous contours and trophoblast pseudoinclusions (15%). In contrast, orderly hierarchical branching of the secondary villi occurred in 31%. p57 immunoexpression was intact in all 25 cases tested. Short tandem repeat genotype testing confirmed a biparental diploid genotype in both of 2 cases tested. Although uncommonly observed in early first-trimester products of conception specimens, the normal chorionic vesicle merits awareness as a potential diagnostic pitfall. While some morphologic features resemble those of a well-developed complete mole, at this early gestational age such features are not expected in a very early complete mole. Attention to the reported gestational age, if available, and presence of embryonic tissues will mitigate against misclassification as complete mole. As with the workup of any potential gestational trophoblastic disease, partnering the clinical and morphologic evaluation with molecular evaluation (intact p57 immunoexpression and lack of any of the characteristic molar genotypes) offers the most precise classification.

Uterine Inflammatory Myofibroblastic Tumors: Proposed Risk Stratification Model Using Integrated Clinicopathologic and Molecular Analysis.

Inflammatory myofibroblastic tumor (IMT) of the uterus is a rare mesenchymal tumor with largely benign behavior; however, a small subset demonstrate aggressive behavior. While clinicopathologic features have been previously associated with aggressive behavior, these reports are based on small series, and these features are imperfect predictors of clinical behavior. IMTs are most commonly driven by ALK fusions, with additional pathogenic molecular alterations being reported only in rare examples of extrauterine IMTs. In this study, a series of 11 uterine IMTs, 5 of which demonstrated aggressive behavior, were evaluated for clinicopathologic variables and additionally subjected to capture-based next-generation sequencing with or without whole-transcriptome RNA sequencing. In the 6 IMTs without aggressive behavior, ALK fusions were the sole pathogenic alteration. In contrast, all 5 aggressive IMTs harbored pathogenic molecular alterations and numerous copy number changes in addition to ALK fusions, with the majority of the additional alterations present in the primary tumors. We combined our series with cases previously reported in the literature and performed statistical analyses to propose a novel clinicopathologic risk stratification score assigning 1 point each for: age above 45 years, size≥5 cm,≥4 mitotic figures per 10 high-power field, and infiltrative borders. No tumors with 0 points had an aggressive outcome, while 21% of tumors with 1 to 2 points and all tumors with ≥3 points had aggressive outcomes. We propose a 2-step classification model that first uses the clinicopathologic risk stratification score to identify low-risk and high-risk tumors, and recommend molecular testing to further classify intermediate-risk tumors.

ALK Immunoexpression is Specific for Inflammatory Myofibroblastic Tumor Among Vulvovaginal Mesenchymal Neoplasms.

Gynecologic tract origin of inflammatory myofibroblastic tumor (IMT), a receptor tyrosine kinase fusion driven tumor with malignant potential, is uncommon and mostly involves the uterine corpus where misclassification as a smooth muscle tumor may occur due to overlapping morphologic features. With rare exception, uterine IMT involves ALK rearrangements and exhibits ALK immunoexpression. Molecularly confirmed vulvovaginal IMT has not been reported, but several low-grade mesenchymal tumors in this region exhibit myxoid stroma and/or inflammatory infiltrates that may resemble IMT. The aims of this study were to define the diagnostic specificity of ALK immunoexpression for IMT among a broad spectrum (107 cases) of vulvovaginal mesenchymal tumors in the differential diagnosis of IMT and to report the clinicopathologic features of vulvovaginal IMT identified in our archives or via retrospective ALK staining of otherwise classified vulvovaginal tumors. Review of archives from 5 different centers revealed a single case of vulvar IMT in a 62-yr-old woman. The 2.5 cm well-circumscribed tumor exhibited the typical microscopic features of IMT, namely a loose fascicular distribution of bland spindle cells within a myxoid stroma, accompanied by an infiltrate of plasma cells, lymphocytes, and eosinophils. The tumor cells exhibited expression for smooth muscle actin, desmin, h-caldesmon, and ALK. Break-apart fluorescence in situ hybridization confirmed the presence of ALK rearrangement. The patient did not receive any treatment and is alive without disease 32 mo later. No evidence of ALK expression was detected in any of the other 107 vulvovaginal tumors, which included 14 aggressive angiomyxomas, 2 superficial angiomyxomas, 12 angiomyofibroblastomas, 8 cellular angiofibromas, 15 smooth muscle neoplasms, 10 peripheral nerve sheath tumors, 20 fibroepithelial polyps, and a variety of other low grade mesenchymal tumors. Although vulvovaginal ALK- rearranged IMT is exceedingly rare, the behavior remains to be fully understood. ALK immunohistochemistry, which appears specific for IMT in this anatomic site, is advised in the evaluation of vulvovaginal mesenchymal tumors exhibiting myxoid stroma and/or an inflammatory infiltrate.

Data Set for Reporting of Uterine Malignant and Potentially Malignant Mesenchymal Tumors: Recommendations From the International Collaboration on Cancer Reporting (ICCR).

The International Collaboration on Cancer Reporting (ICCR) seeks to produce standardized, evidence-based protocols for the reporting of tumors with the aim of ensuring that all cancer reports generated worldwide will be of similar high quality and record the same elements. Herein, we describe the development of the data set for the reporting of uterine malignant and potentially malignant mesenchymal tumors by a panel of expert pathologists and a single clinician and provide the commentary and rationale for the inclusion of core and noncore elements. This data set, which incorporates the recent updates from the 5th edition of the World Health Organization Classification of Female Genital Tumors, addresses several subjects of debate including which mesenchymal tumors should be graded, how to document extent of invasion, mitotic counts, and the role of ancillary testing in tumor diagnosis and patient management. The inclusion of elements is evidence-based or based on consensus of the expert panel with clinical relevance being the guiding standard.

Homologous Recombination Deficiency and Ovarian Cancer Treatment Decisions: Practical Implications for Pathologists for Tumor Typing and Reporting.

Clinical testing for homologous repair (HR) deficiency (HRD) in ovarian cancers has emerged as a means to tailor the use of poly(ADP-ribose)polymerase (PARP) inhibitor therapy to the patients most likely to respond. The currently available HRD tests evaluate tumor tissue for genomic evidence of impairment of the HR pathway of DNA damage repair, which, if present, renders the tumor vulnerable to PARP inhibitors in conjunction with platinum chemotherapy. Germline or somatic mutation of BRCA1/2 is a major contributor HRD. Thus, tubo-ovarian/peritoneal high-grade serous carcinoma (HGSC) is enriched by HRD. After highlighting the general concepts underlying HRD testing and PARP inhibitor therapy, this review discusses practical roles for pathologists to maximize the opportunities for eligible patients with ovarian cancer to benefit from HRD testing, chiefly by applying contemporary diagnostic criteria for ovarian cancer tumor typing and navigating through potential pitfalls of tumor types that may mimic HGSC but are unlikely to harbor HRD.

Regional air transportation of ovarian tissue for cryopreservation in a prepubertal female with cancer.

Ovarian tissue cryopreservation is the only fertility preservation (FP) option available to prepubescent females receiving gonadotoxic therapy, but it has limited availability. A 6-year-old female was diagnosed with high-risk rhabdomyosarcoma, and the planned treatment carried an 80% risk of ovarian failure. Her parents desired FP, but the nearest center was 500 miles away. The patient underwent oophorectomy at the cancer center with air transport of the tissue to the oncofertility center, where it was successfully cryopreserved. Formation of networks between full-service and limited oncofertility centers in a hub-and-spoke model would increase access to FP services, particularly in children.

Differentiating complete hydatidiform mole and coexistent fetus and placental mesenchymal dysplasia: A series of 9 cases and review of the literature.

To identify the differentiating features in clinical presentation, management, and maternal/fetal outcome in complete hydatidiform mole and coexistent fetus compared with placental mesenchymal dysplasia. Between 1997 and 2015, five women with complete hydatidiform mole and coexistent fetus and four women with placental mesenchymal dysplasia were managed at the University of California San Francisco. Clinical features were analyzed and compared with previously published data. Of the five cases of complete hydatidiform mole and coexistent fetus, two had live births. ß-hCG levels were > 200,000 IU/L in all cases. On imaging, a clear plane between the cystic component and the placenta favored a diagnosis of complete hydatidiform mole and coexistent fetus. None of the patients went on to develop gestational trophoblastic neoplasia (GTN), with a range of follow-up from 2 to 38 months. Combining this data with previously published work, the live birth rate in these cases was 38.8%, the rate of persistent GTN was 36.2%, and the rate of persistent GTN in patients with reported live births was 27%. Of the four cases of placental mesenchymal dysplasia, all four had live births. One patient developed HELLP syndrome and intrauterine growth restriction; the remaining three were asymptomatic. Maternal symptoms, fetal anomalies, ß-hCG level, and placental growth pattern on imaging may help differentiate between complete hydatidiform mole and coexistent fetus and placental mesenchymal dysplasia. There was not an increased risk of gestational trophoblastic neoplasia in patients with complete hydatidiform mole and coexistent fetus who opted to continue with pregnancy.

Cytoplasmic Pattern p53 Immunoexpression in Pelvic and Endometrial Carcinomas With TP53 Mutation Involving Nuclear Localization Domains: An Uncommon But Potential Diagnostic Pitfall With Clinical Implications.

A cytoplasmic pattern of p53 immunohistochemical expression has recently been reported in a rare subset of pelvic and endometrial cancers with a TP53 mutation involving domains affecting nuclear localization. This study reports the clinicopathologic features of 31 cases with a TP53 mutation involving nuclear localization, the largest study to date, emphasizing practical strategies for recognizing this uncommon variant and distinguishing it from the p53 wild-type pattern. The study also evaluates the prognostic significance of TP53 mutation involving nuclear localization in the ovarian high-grade serous carcinoma (HGSC) cohort of The Cancer Genome Atlas database. Most of the 31 tumors were advanced stage pelvic or endometrial HGSC. All TP53 mutations were predicted to result in loss of function. The p53 overexpression pattern was present in 6 tumors; the p53 null pattern in 3 and the p53 cytoplasmic pattern in 22 tumors. The p53 cytoplasmic pattern predominantly consisted of weak to moderate cytoplasmic staining in >95% of tumor cells as well as variable intensity nuclear staining involving a range of just a few cells to just under 80% of tumor cells. The p53 cytoplasmic pattern was observed in 100% of tumors with TP53 mutation in the nuclear localization domain and in 33% to 44% of tumors with a mutation in the adjacent tetramerization domain or nuclear exclusion sequence (P<0.01). p16 immunoexpression was present in 74% of tumors. In The Cancer Genome Atlas ovarian HGSC cohort, 9% of 471 nonredundant TP53-mutant cases had a nuclear localization domain, tetramerization domain, or nuclear exclusion sequence mutation but there was no significant difference in survival when compared to cases with TP53 mutation outside those domains (P>0.05). p53 cytoplasmic staining merits classification as an aberrant result despite coexisting nuclear staining that in some cases may resemble the p53 wild-type pattern. While positive p16 immunostaining may be of value to confirm diagnostically challenging cases of p53 cytoplasmic staining, a negative result is noninformative and molecular testing for TP53 mutation should be considered, if available.

Survey Results on Pathologic Aspects of Endocervical Adenocarcinoma by the International Society of Gynecological Pathologists.

The International Society of Gynecological Pathologists (ISGyP) undertook a project to provide evidence-based recommendations for pathologic reporting of all aspects of endocervical adenocarcinoma. The first step in the process was the design of an extensive survey to collect baseline information on existing practices regarding grossing, processing, diagnosing, and reporting of endocervical adenocarcinoma among the members of the society. The web-based survey of 98 questions was emailed to all members of ISGyP and there were 175 respondents (38.5% of ISGyP members). The responses, as expected, revealed areas of uniformity but also areas of substantial variation. The results of the survey are presented herein and assisted in developing the recommendations presented in the other reviews in this issue.

The ISGyP Endocervical Adenocarcinoma Project: Master Plan Summary, Acknowledgment of Participants, and Participant Responses to Final Recommendations of the Expert Panels.

The International Society of Gynecological Pathologists carried out a multifaceted project with the broad aim of improving the pathological reporting of endocervical adenocarcinoma (EAC). The intentions were to promote and align practices with the WHO 2020 classification, which endorses HPV status-based classification of EAC and the Silva pattern-based assessment of HPV-associated EAC, to promote uniformity in applying the recent FIGO staging revisions on cervical carcinoma, and to provide best practice guidelines on all aspects of EAC pathology reporting. To facilitate the use of the new WHO/IECC classification and the Silva system, two online educational portals were set up with training and test sets of scanned slides; these remain available to society members on the ISGyP educational website. In addition, a large international collaborative individual data collection project is ongoing, aiming to ascertain the prognostic value of EAC categories, and to provide a database with the potential to address unanswered questions. A single on-site meeting was held on February 29, 2020 in Los Angeles, in advance of the USCAP Annual Meeting; all other correspondence was by email and through electronic surveys. Project participants were invited to vote and comment on the recommendations contained within the practice guideline articles. The project received an enthusiastic response from pathologists across the world. This report includes an overview and summary of all aspects of the project, a list of participants and the results of polling on practice recommendations.

Online Training and Self-assessment in the Histopathologic Classification of Endocervical Adenocarcinoma and Diagnosis of Pattern of Invasion: Evaluation of Participant Performance.

Histopathologic classification of endocervical adenocarcinomas (EAC) has recently changed, with the new system based on human papillomavirus (HPV)-related morphologic features being incorporated into the 5th edition of the WHO Blue Book (Classification of Tumours of the Female Genital Tract). There has also been the introduction of a pattern-based classification system to assess invasion in HPV-associated (HPVA) endocervical adenocarcinomas that stratifies tumors into 3 groups with different prognoses. To facilitate the introduction of these changes into routine clinical practice, websites with training sets and test sets of scanned whole slide images were designed to improve diagnostic performance in histotype classification of endocervical adenocarcinoma based on the International Endocervical Adenocarcinoma Criteria and Classification (IECC) and assessment of Silva pattern of invasion in HPVA endocervical adenocarcinomas. We report on the diagnostic results of those who have participated thus far in these educational websites. Our goal was to identify areas where diagnostic performance was suboptimal and future educational efforts could be directed. There was very good ability to distinguish HPVA from HPV-independent adenocarcinomas within the WHO/IECC classification, with some challenges in the diagnosis of HPV-independent subtypes, especially mesonephric carcinoma. Diagnosis of HPVA subtypes was not consistent. For the Silva classification, the main challenge was related to distinction between pattern A and pattern B, with a tendency for participants to overdiagnose pattern B invasion. These observations can serve as the basis for more targeted efforts to improve diagnostic performance.

Endocervical Adenocarcinoma, Gross Examination, and Processing, Including Intraoperative Evaluation: Recommendations From the International Society of Gynecological Pathologists.

The International Society of Gynecological Pathologists (ISGyP) Endocervical Adenocarcinoma Project aims to provide evidence-based guidance for the pathologic evaluation, classification, and reporting of endocervical adenocarcinoma. This review presents the recommendations pertaining to gross evaluation and intraoperative consultation of specimens obtained from patients in the setting of cervical cancer. The recommendations are the product of review of published peer-reviewed evidence, international guidelines and institutional grossing manuals, as well as deliberation within this working group. The discussion presented herein details the approach to the different specimen types encountered in practice: loop electrosurgical excision procedure, cone, trachelectomy, radical hysterectomy, pelvic exenteration, and lymphadenectomy specimens. Guidelines for intraoperative evaluation of trachelectomy and sentinel lymph node specimens are also addressed. Correlation with ISGyP recommendations on cancer staging, which appear as a separate review in this issue, is also included when appropriate. While conceived in the framework of endocervical adenocarcinoma, most of the discussion and recommendations can also be applied to other cervical malignancies.