Inter-pathologist reproducibility in classifying extraovarian implants in borderline serous ovarian tumor and low-grade serous carcinoma

Progressive loss of selenium-binding protein 1 expression correlates with increasing epithelial proliferation and papillary complexity in ovarian serous borderline tumor and low-grade serous carcinoma

The paper presents an immunohistochemical study of greater omenta in serous borderline ovarian tumors. The role of scavenger receptors in the cells of the greater omentum in this pathology has not been sufficiently studied. Theat is why, this work is of scientific interest, and the topic under study is relevant. The purpose of the study is to analyze the expression level of scavenger receptors on macrophages in the greater omentum in serous borderline ovarian tumors. Materials and methods. The study determined the expression of scavenger receptors by immunohistochemical methods on macrophages of the greater omentum in 40 patients. The entry criteria were the presence of serous borderline ovarian tumors in the patients, surgical treatment for borderline ovarian tumors with omentectomy, as well as the age of the patients from 20 to 45 years. The exclusion criteria were severe concomitant diseases in patients. The expression of scavenger receptors on macrophages of the greater omentum was evaluated. Markers of macrophages CD91 (SR-L1), CD204 (SR-A1), CD68 (SR-D1) were studied: antibodies to macrophage markers CD91, CD204, CD68 were used. A morphometric study of the preparations was conducted. The STATISTICA 10 program (StatSoft) was used for statistical processing of the results obtained. Research results. In the study of greater omentum preparations in serous borderline ovarian tumors, when assessing the level of CD91 (SR-L1) expression, it was shown that in serous borderline tumors without implantation damage, the average CD91 expression score was lower than that in serous borderline tumors with implantation damage. The analysis of CD204 (SR-A1) expression in the greater omentum demonstrated that in serous borderline tumors without implantation lesion, the average CD204 expression score was lower than that in serous borderline tumors with implantation lesion. When assessing the expression level of CD68 (SR-D1) in the greater omentum, it was found that in serous borderline tumors without implantation lesion, the average CD68 expression score was lower compared with a serous borderline tumors with implantation lesion. Conclusions. The greater omentum participates in implementing immune reactions due to the population of macrophages expressing scavenger receptors. These cells trigger the initiation of antitumor immunity by increasing the number of CD68+, CD91+, CD204+ and have the ability to inhibit the formation of tumors dissemination.

Low-grade peritoneal serous carcinomas have been the subject of limited study, and their distinction from peritoneal serous psammocarcinomas and serous borderline tumors is not always easy. The clinicopathologic features of 14 low-grade serous carcinomas, 7 psammocarcinomas, and 19 serous borderline tumors of peritoneal origin were compared. Average ages were 58 years (low-grade serous carcinomas), 48 years (borderline tumors), and 40 years (psammocarcinomas). Typical clinical presentations were abdominal pain, abdominal mass, or both, with the tumors incidental in 37% (borderline tumors), 43% (psammocarcinomas), and 36% (low-grade serous carcinoma). Operative and gross findings varied from nodules to adhesions to a dominant mass. Treatment was surgical debulking in most cases, with biopsy alone for eight borderline tumors. Seven patients with low-grade serous carcinoma were alive when last seen, but follow-up duration is short (average, 1.2 years): five were without disease, one had recurrent disease and one persistent disease. One patient with serous carcinoma died of disease at 3.5 years, and two patients died of other causes. Three patients with psammocarcinoma were alive without disease (average 3.3 years). Fourteen patients with borderline tumors were alive (average 3 years): 10 were without disease, 2 had persistent disease, and serous carcinoma developed in 2. The low-grade serous carcinomas resembled the invasive implants of ovarian serous borderline tumors. lacked high-grade nuclear atypia, showed tissue, lymphovascular space invasion, or both and had appreciable solid epithelial proliferation. Some serous carcinomas showed abundant psammomatous calcification suggesting psammocarcinoma but had too much epithelial proliferation for that diagnosis. The psammocarcinomas showed at least 75% psammoma bodies, no more than moderate cytological atypia, tissue or lymphovascular space invasion, or both, and rare epithelial proliferation less than 15 cells across. Adequate sampling was necessary to identify invasion, with highest yields of invasive foci in omental samples; individual foci in some cases of carcinoma resembled borderline tumor. The serous borderline tumors resembled the noninvasive implants of ovarian serous borderline tumors, lacked invasion, and did not show nuclear atypia of the degree seen in grade 2 or grade 3 serous carcinoma. Low-grade serous carcinoma, psammocarcinoma, and serous borderline tumors of peritoneal origin share some clinicopathologic features and may be underrecognized at surgery and gross examination. Because of overlapping microscopic patterns, adequate sampling is mandatory to identify small foci of invasion that exclude a borderline tumor and identify significant cellularity that excludes a psammocarcinoma. Conservative therapy is merited for younger women with borderline tumors. Maximum debulking is recommended for bulky symptomatic borderline tumors, low-grade serous carcinoma, and psammocarcinoma. Although short-term outcomes for the carcinomas appear favorable, follow-up is too limited to determine long-term outcomes.

Epithelial ovarian neoplasms are a heterogeneous group including tumor subsets with distinct clinicopathologic and molecular features. Recent evidence from molecular and genomic studies suggests that whereas low-grade serous carcinomas and high-grade serous carcinomas likely develop on two separate pathways, the low-grade serous carcinomas and serous borderline ovarian tumors may represent various stages of the same developmental continuum. The transformation of borderline ovarian tumors into an invasive neoplasm is associated with an array of molecular changes, inter alia controlled by p53 and PI3K/Akt pathway, as well as with a decrease in E-cadherin expression. The latter implies that epithelial-mesenchymal transition is a critical determinant of borderline ovarian tumor invasiveness. The aim of this study was to analyze the expression of transcription factors involved in epithelial-mesenchymal transition: SNAIL, SLUG, TWIST 1, TWIST 2, ZEB 1, and ZEB 2 in borderline tumors and type I ovarian cancers. The study included tissue specimens from 42 patients with histopathologically verified ovarian masses. The expressions for SLUG, TWIST 1, ZEB1, and ZEB 2 were scored based on the nuclear staining, and the expressions of SNAIL and TWIST 2 based on the cytoplasmic and/or nuclear staining. The proportions of ovarian tumors with the immunoexpression of the epithelial-mesenchymal transition transcription factors were 85.7% for SNAIL, 100% for SLUG, 9.5% for TWIST 1, 95.2% for TWIST 2, 23.8% for ZEB 1, and 0% for ZEB 2. The expression patterns of SNAIL, SLUG, TWIST, and ZEB identified in this study suggest that both serous borderline ovarian tumors and type I ovarian cancers undergo dynamic epithelial-mesenchymal interconversions. Our findings obtained in the two groups of tumors which shared some etiopathogenic pathways imply that the expression of the epithelial-mesenchymal transition transcription factors may be activated at early stages of the epithelial-mesenchymal transition, and thus these molecules may play a pivotal role in the development of both serous borderline ovarian tumors and type I ovarian cancer.

Malignant transformation of the fallopian tube mucosa, followed by exfoliation of malignant cells onto ovarian and/or peritoneal surfaces, has been implicated as the origin of most pelvic high-grade serous carcinoma. Whether a parallel pathway exists for pelvic low-grade serous tumors [ovarian serous borderline tumor (SBT) and low-grade serous carcinoma (LGSC)] remains to be fully elucidated. The literature is challenging to interpret due to variation in the diagnostic criteria and terminology for cytologically low-grade proliferations of the fallopian tube mucosa, as well as variation in fallopian tube specimen sampling. Recently, a candidate fallopian tube precursor to ovarian SBT, so-called papillary tubal hyperplasia, was described in advanced stage patients. The current study was designed to identify fallopian tube mucosal proliferations unique to patients with low-grade serous ovarian tumors (serous cystadenoma, SBT, LGSC) and to determine if they may represent precursors to the ovarian tumors. Fallopian tubes were thinly sliced and entirely examined microscopically, including all of the fimbriated and nonfimbriated portions of the tubes, from patients with ovarian serous cystadenoma (35), SBT (61), and LGSC (11) and from a control population of patients with ovarian mucinous cystadenoma (28), mature cystic teratoma (18) or uterine leiomyoma (14). The slides of the fallopian tubes were examined in randomized order, without knowledge of the clinical history or findings in the ovaries or other organs. Alterations of the mucosa of the fallopian tube were classified as type 1: nonpapillary proliferation of cytologically bland tubal epithelium exhibiting crowding, stratification, and/or tufting without papillary fibrovascular cores or as type 2: papillary alterations consisting of a fibrovascular core lined by a cytologically bland layer of tubal epithelium. A third abnormality, type 3, consisted of detached intraluminal papillae, buds, or nests of epithelium that cytologically resembled the epithelial component of SBT or LGSC. Mucosal proliferations were identified in subsets of all populations, including the control populations. Overall, type 1 proliferations were in 28% to 61% of all patients and type 2 alterations in 4% to 16%. There was no statistically significant difference in the incidence of type 1 or type 2 proliferations between the class of ovarian serous tumors (benign, SBT, LGSC), between early and advanced stage SBT, or between patients with any ovarian serous tumor and the control population of nonserous diagnoses. Type 3 alterations were only identified in patients with advanced stage SBT/LGSC and not in any early stage SBT or cystadenoma. These findings suggest that type 3 alterations floating in the fallopian tube lumen represent exfoliation of tumor cells from ovarian and/or peritoneal origin. Our study did not identify a mucosal-based proliferation of the fallopian tubes that was specific to ovarian low-grade serous tumors. Cytologically bland mucosal proliferations appear to be common in fallopian tubes from patients of all ages and unrelated to ovarian tumorigenesis. A consensus on diagnostic criteria and terminology for these types of proliferations is needed, as well as further study into their etiology, including possible association with hormonal environment.

Patients with ovarian serous cancer are usually younger and survive longer than patients with high-grade serous cancer. Unfortunately, most low-grade serous cancer patients eventually die of the disease because recurrent low-grade serous carcinoma is relative chemoresistant. So far, the known mutations identified in low-grade ovarian serous carcinomas and their putative precursor ovarian serous borderline tumors are BRAF and KRAS mutations. BRAF and KRAS mutations together have been identified in approximately 60% of serous borderline tumors and early stage low-grade serous carcinomas. However, BRAF mutation is rare in advanced-stage low-grade serous carcinomas. To further investigate the molecular pathogenesis of low-grade serous carcinoma, mutation analyses of 409 cancer related genes were performed in 21 low-grade ovarian serous carcinoma, 8 ovarian serous borderline tumors and one ovarian cystadenoma using next generation sequencer. A total of nineteen missense mutations were identified in 20 samples but ten samples had no detectable mutations. BRAF mutation was detected in 3 serous borderline tumors and one low-grade serous carcinoma. KRAS mutations were detected in three low-grade serous carcinomas. Other than BRAF and KRAS mutations, we also detected other prevalent mutations: ATRX mutations were detected in 3 low-grade ovarian serous carcinomas and a cystadenoma; KMT2C mutations were detected in 3 low-grade ovarian serous carcinomas; ATM mutations were detected in 2 low-grade ovarian serous carcinomas. Interestingly, both ATRX and MLL3 genes are involved in the chromatin remodeling. Moreover, both ATRX and ATM are involved in DNA damaging response. Thus, the pathogenesis of low-grade serous carcinoma may involve de-regulation of chromatin remodeling pathway and DNA damaging response. Further analysis of a large cohort of low-grade serous carcinomas for these prevalent mutations is ongoing. Citation Format: Yvonne TM Tsang, Daisy Izaguirre, Suet-Yan Kwan, Samuel C. Mok, David Gershenson, Kwong-Kwok Wong. Ovarian low grade serous cancer: Mutation analysis with a comprehensive 409 cancer gene panel. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1529. doi:10.1158/1538-7445.AM2014-1529

Evaluation of MTAP immunohistochemistry loss of expression in ovarian serous borderline tumors as a potential marker for prognosis and progression

The infrequent association of serous borderline tumors (SBTs) with invasive serous carcinoma has led to the view that SBTs are unrelated to invasive serous carcinoma. Nonetheless, mortality associated with SBTs is generally attributed to malignant transformation, and traditionally these tumors have been designated as "carcinomas of low malignant potential." Previous immunohistochemical studies evaluating p53 expression and molecular genetic studies evaluating mutational status have reported that p53 overexpression and mutations are infrequent in SBTs and occur in as many as 50% to 80% of invasive serous carcinomas. The different methodologies for determining p53 status and the failure to correlate the findings with tumor grade make these studies difficult to interpret. The current study was undertaken to overcome these deficiencies and to reconcile the relationship of SBTs to invasive serous carcinoma by performing a morphologic, immunohistochemical, and molecular genetic analysis comparing SBTs with low- and high-grade serous carcinoma. The molecular genetic analysis used a highly stringent, carefully designed nucleotide-sequencing method. A total of 96 sporadic serous tumors including 25 SBTs (11 atypical proliferative serous tumors and 14 intraepithelial low-grade serous carcinomas [noninvasive micropapillary serous carcinomas, MPSCs]), 12 low-grade serous carcinomas (invasive MPSCs), and 59 high-grade serous carcinomas were analyzed for their p53 mutational status of exons 5 to 9. Functional mutations, defined as mutations resulting in the alteration of the structure of the encoded protein, were detected in 30 of 59 (50.8%) high-grade serous carcinomas and 1 (8.3%) of 12 low-grade invasive serous carcinomas compared with 2 (8%) of 25 SBTs, both of these in intraepithelial low-grade serous carcinomas (noninvasive MPSCs). The similar frequency of p53 mutations in SBTs and low-grade invasive serous carcinomas in contrast to the significantly higher frequency of p53 mutations in high-grade serous carcinomas (P < 0.0005) suggests a common lineage for SBTs and low-grade invasive serous carcinomas and supports the view that SBTs are unrelated to the usual type of invasive serous carcinoma, which is a high-grade neoplasm. Mutational status was also correlated with p53 immunoreactivity. Although p53 immunoreactivity is generally higher in those specimens containing mutant p53, immunostaining is neither sufficiently specific nor sensitive enough to predict p53 mutations. The molecular genetic findings confirm our hypothesis of dual pathways of serous carcinogenesis based on previous analyses of KRAS and BRAF mutations on the same set of cases in which KRAS and BRAF mutations were found in 60% of SBTs and low-grade serous carcinoma but not in high-grade serous carcinomas. Based on these studies, we have proposed a model of serous carcinogenesis in which SBTs are the precursors of low-grade serous carcinomas whereas the usual type of invasive serous carcinoma is a high-grade neoplasm that develops "de novo" from in situ alterations in epithelial inclusion cysts.

We examined the expression of apoptosis-related proteins in serous versus mucinous borderline ovarian tumours, in comparison with benign and malignant ovarian tumours. Immunohistochemical expression of pro-apoptotic (p53, p21, bax, bak, fas) and anti-apoptotic proteins (bcl-2, bcl-x) was determined in 34 borderline (19 mucinous, 15 serous), 20 benign (10 mucinous, 10 serous) and 28 malignant ovarian tumours (9 mucinous, 19 serous). A difference in semi-quantitative p53 expression was found between benign and borderline tumours (P = 0.01), but not between borderline and malignant tumours. Increased p21 expression was found in borderline versus benign tumours (P = 0.004). Bcl-2 expression was lower in borderline than in benign (P = 0.01) and malignant tumours (P = 0.02). No difference in bax, bak, fas or bcl-x expression was observed among the three tumour types. Higher percentage of p21 positive cells was found in serous than in mucinous borderline tumours (P < 0.001). Bcl-2 expression was higher in serous than in mucinous forms of benign (P < 0.001), borderline (P < 0.001), and malignant tumours (P < 0.003). No difference in p53, bax, bak, fas or bcl-x expression was observed between serous and mucinous borderline ovarian tumours. Although p53 overexpression was a common feature of both mucinous and serous borderline tumours, p21 and bcl-2 overexpression appeared specific to serous tumours.

ObjectiveTranscriptional profiling of epithelial ovarian cancer has revealed molecular subtypes correlating to biological and clinical features. We aimed to determine gene expression differences between malignant, benign and borderline serous ovarian tumors, and investigate similarities with the well-established intrinsic molecular subtypes of breast cancer.MethodsGlobal gene expression profiling using Illumina's HT12 Bead Arrays was applied to 59 fresh-frozen serous ovarian malignant, benign and borderline tumors. Nearest centroid classification was performed applying previously published gene profiles for the ovarian and breast cancer subtypes. Correlations to gene expression modules representing key biological breast cancer features were also sought. Validation was performed using an independent, publicly available dataset.Results5,944 genes were significantly differentially expressed between benign and malignant serous ovarian tumors, with cell cycle processes enriched in the malignant subgroup. Borderline tumors were split between the two clusters. Significant correlations between the malignant serous tumors and the highly aggressive ovarian cancer signatures, and the basal-like breast cancer subtype were found. The benign and borderline serous tumors together were significantly correlated to the normal-like breast cancer subtype and the ovarian cancer signature derived from borderline tumors. The borderline tumors in the study dataset, in addition, also correlated significantly to the luminal A breast cancer subtype. These findings remained when analyzed in an independent dataset, supporting links between the molecular subtypes of ovarian cancer and breast cancer beyond those recently acknowledged.ConclusionsThese data link the transcriptional profiles of serous ovarian cancer to the intrinsic molecular subtypes of breast cancer, in line with the shared clinical and molecular features between high-grade serous ovarian cancer and basal-like breast cancer, and suggest that biomarkers and targeted therapies may overlap between these tumor subsets. The link between benign and borderline ovarian cancer and luminal breast cancer may indicate endocrine responsiveness in a subset of ovarian cancers.

Background/Objectives: Since non-invasive implants and invasive implants (metastases) are a key point of differentiation between serous borderline tumors (SBTs) and low-grade serous carcinoma (LGSC), the correct diagnosis of these two types of extraovarian lesions is crucial for patient treatment and prognosis. However, accurate diagnosis can be challenging even for experienced pathologists. The aim of this study was to evaluate interobserver agreement in the classification of these extraovarian lesions. Methods: Twenty-four cases of ovarian SBT and LGSC with 33 samples of non-invasive implants of SBT and metastasis of LGSC were independently reviewed by three gynecologic pathologists and three general pathologists. Diagnostic criteria included destructive invasion, micropapillary architecture, and retraction clefts. To measure interobserver agreement, Fleiss' kappa and Cohen's kappa were calculated, with consensus diagnoses determined by the majority of gynecologic pathologists. Results: According to the consensus, diagnosis 42.4% biopsies were classified as metastases of LGSC and 57.6% as non-invasive implants of SBT. Overall reproducibility was substantial (κ = 0.61). The agreement among gynecologic pathologists, as well as between gynecologic pathologists and the consensus (using leave-one-out reference), was substantial to near-perfect (κ = 0.745-0.821). General pathologists' agreement with the consensus was moderate (κ = 0.467-0.698). Agreement between general pathologists was also moderate, with κ values ranging from 0.413 to 0.518. The difference in pairwise agreement between the two groups was statistically significant, confirming that gynecologic pathologists outperformed general pathologists in classifying extraovarian lesions. Conclusions: The results showed that current diagnostic reproducibility remains suboptimal, particularly among general pathologists, underscoring the need for improved training and standardized criteria. Ultimately, a multidisciplinary approach combining morphological expertise, immunohistochemical validation and molecular stratification will be essential for optimizing diagnosis and treatment.

The Idylla NRAS Mutation Test, performed on the Biocartis Idylla system, is an in vitro diagnostic tool for the qualitative assessment of 18 NRAS mutations in codons 12, 13, 59, 61, 117, and 146. Low-grade serous ovarian cancer (LGSC) represents less than 10% of all serous ovarian carcinomas. LGSCs are believed to arise from preexisting cystadenomas or serous borderline tumors (SBOTs) that eventually progress to an invasive carcinoma. The molecular analysis of cancer-causing mutations and the development of targeted biological therapies constitute a milestone in the diagnosis and therapy of ovarian malignancies. According to some authors, NRAS may be an important oncogene for the progression of SBOT to a frankly invasive disease. The primary aim of this study was to verify if a fully integrated, real-time PCR-based Idylla system can be used for the rapid determination of the NRAS mutation status in patients with serous borderline ovarian tumors and low-grade serous ovarian carcinomas. The study included tissue specimens from 12 patients with histopathologically verified ovarian masses, operated on at the Department of Obstetrics and Gynecology, Nicolaus Copernicus University, Collegium Medicum in Bydgoszcz (Poland), between January 2009 and June 2012. The mean age of the study patients was 52.5 years (range 27–80 years). NRAS mutation in codon 13 (G13D, p.Gly13Asp; nucleotide: c.38G>A) was found in one patient, a woman with low-grade serous ovarian carcinoma. To the best of our knowledge, our experiment was the first published study using the novel Idylla NRAS Mutation Test for the evaluation of ovarian tumors in a clinical setting. The Idylla platform is an interesting ancillary first-line rapid and fully automated instrument to detect NRAS mutations in SBOTs and LGSCs. However, the clinical usefulness of this method still needs to be verified in larger groups of cancer patients.

A study detection of the ROS1 gene fusion by FISH and ROS1 protein expression by IHC methods in patients with ovarian malignant or borderline serous tumors

Molecular subtypes of serous borderline ovarian tumor show distinct expression patterns of benign tumor and malignant tumor-associated signatures

About 15-20% of all ovarian neoplasms are of borderline type (or atypical proliferative or carcinoma of low malignant potential). They represent a common diagnostic and treatment problem both for the pathologist and for clinicians. The borderline tumors occur most commonly in childbearing age, show an indolent course and have good prognosis but are resistant to the traditional chemotherapies. The serous borderline tumors are the most common types of borderline ovarian tumors and they can cause differential diagnostic problems even for the experienced pathologist. We studied 30 cases which were diagnosed in our institute from 2000 to 2008. Thirteen were typical serous borderline tumors, in 7 cases the pattern was micropapillary, in 2 cases with microinvasion and in the remaining 8 cases the borderline tumors were associated with low-grade serous carcinomas. Seventeen of the 22 borderline cases were stage I tumors. There were noninvasive implants in the remaining 5 cases and in the cases of the low-grade carcinomas we could find, besides the noninvasive implants (in 3 cases), invasive implants or metastasis too. The main diagnostic problems in serous ovarian borderline tumors are the presence of micropapillary pattern, to detect microinvasion, or to differentiate the pseudo-borderline pattern of the low-grade serous tumors from a real borderline tumor and especially to diagnose the extraovarian diseases (types of implants). We discuss these diagnostic problems and criteria according to recent literature and our experience.