Biocompatibility of three different root canal sealers, experimental study

OBJECTIVES

This study was assessed the biocompatibility of three different root canal sealers (Well-Root St, GuttaFlow Bioseal, and AH-Plus) following implantation in rat subcutaneous tissues, using histopathological immunohistochemical analysis.

METHODS

Four groups of eighty-four male rats each underwent subcutaneous dorsal implantation of a polyethylene tube, either empty or filled. Tissues were collected, fixed, and processed for histological analysis after 7, 15, and 30 d. Slides were photographed and digitally processed to identify lymphocytes and macrophages using Cluster of differentiation 3 (CD3) and cluster of differentiation 68 (CD68) markers, respectively. P was set at 0.05, when lymphocyte and macrophage infiltration was compared between groups and observation times using one-way analysis of variance (ANOVA).

RESULTS

Histopathological analysis of all groups revealed an inflammatory reaction followed by the emergence of a fibrous capsule after 7 days. After 30 days, the thickness of the fibrous capsule and the inflammatory response subsided. CD3 staining for immunohistochemical analysis revealed that the AH-Plus group had the highest mean percentage of lymphocyte infiltration at 7 and 15 days, followed by the Well-Root St, GuttaFlow Bioseal, and Control groups. After 30 days, no discernible difference was observed between the groups in terms of the mean percentage of lymphocyte infiltration. After 7, 15, and 30 days, there was a significant difference in the mean percentage of macrophage infiltration across the groups, as demonstrated by CD68 staining. After 7, 15, and 30 days, the AH-Plus group had the highest mean percentage of macrophage infiltration, followed by the Well-Root St. and GuttaFlow Bioseal groups, while the control group had the lowest mean percentage.

CONCLUSION

All observational periods showed minimal inflammatory reactions to GuttaFlow Bioseal. After subcutaneous tissue implantation in a rat model, the initial inflammatory reactions to Well-Root St and AH-Plus had abated by day 30, and all tested sealers had outstanding biocompatibility.

Bilateral Ovarian Juvenile Granulosa Cell Tumor with Extensive Extracellular Mucin Deposition in an Adolescent: Report of a Rare Presentation with a Comprehensive Review of the Literature

Juvenile granulosa cell tumor (JGCT) of the ovary is an uncommon malignancy, with most cases seen in adolescent girls and young women. The majority of these patients present with unilateral ovarian disease, and to date, bilateral JGCTs have been reported in 10 cases. Although the histopathologic features have been detailed in the published literature, extensive extracellular mucin deposition has been documented in only one case. Herein, we report a 17-year-old adolescent girl with bilateral solid-cystic adnexal masses diagnosed as bilateral JGCT with abundant extracellular mucin deposition on histopathology. The index case highlights a rare clinical and histopathologic presentation of JGCT. Adequate knowledge of such unusual presentations is essential for accurate distinction from other ovarian tumors and appropriate management.

Pure Ovarian Dysgerminoma in a Postmenopausal Patient: A Case Report and Review of the Management

•

Pure dysgerminomas in postmenopausal females are rare.

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Ovarian dysgerminoma symptoms are non-specific.

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Treatment options have traditionally included surgical resection and chemotherapy.

Background

A pure ovarian dysgerminoma in a postmenopausal female is a rare phenomenon.

Case

A 65-year-old female presented with a large pelvic mass. Following surgical debulking, the patient was diagnosed with FIGO Stage IIB ovarian dysgerminoma. She was treated with three cycles of etoposide and cisplatin and has been disease-free for 12 months.

Conclusion

Dysgerminomas in postmenopausal females are uncommon. Gynecologic oncologists should be familiar with the pathological diagnosis and treatment recommendations to achieve optimal outcomes.

Inter‑component immunohistochemical assessment of proliferative markers in uterine carcinosarcoma

In the scientific literature, a selected number of reports have investigated the impact of proliferative activity on the development and progression of uterine carcinosarcomas (UC). The aim of the present retrospective study was to compare the immunohistochemical proliferation markers [Ki67, proliferating cell nuclear antigen (PCNA), minichromosome maintenance complex component 3 (MCM3), and topoisomerase IIα (topoIIα)] assessment in both components of UC. A total of 30 paraffin-embedded slides of UCs, obtained from patients who underwent surgery between January 1, 2006, and December 31, 2020, were analyzed. Medical records and clinicopathological data of patients were reviewed. Formalin-fixed, paraffin-embedded tissue sections were immunostained with monoclonal antibodies against Ki67, PCNA, MCM3 and topoIIα. Ki67-positive nuclear immunoreactivity was reported in 20 (67%) and 16 (53%) UC carcinomatous and sarcomatous components, respectively. In the epithelial component, Ki67 positive staining was related to the International Federation of Gynecology and Obstetrics (FIGO) stage (P=0.025), and histological grade (G1 vs. G2/G3, P=0.031). Nuclear PCNA reactivity was observed in 18 (60%) and 16 (53%) carcinomatous and sarcomatous components, respectively. Notably, all four cases with omental metastases were PCNA-positive, and a relationship between staining pattern and the existence of metastases was of significant value (P=0.018). MCM3-positive nuclear staining was found nearly twice as high in the carcinomatous (n=19; 63%), compared with the sarcomatous (n=11; 37%) component, respectively, and MCM3 expression in the epithelial component was related to clinical stage (P=0.030), and the existence of omental metastasis (P=0.012). In addition, out of the 30 UCs, 17 (57%) and 13 (43%) showed topoIIα positivity in the carcinomatous and sarcomatous UC components, respectively. A significant relationship between protein immunoreactivity and FIGO stage (P=0.049), and omental metastasis (P=0.026) was revealed to exist. However, no significant differences between expression of proliferation markers and clinicopathological features in the sarcomatous UC component were identified. Finally, a significant correlation between each protein immunohistochemical staining was demonstrated, particularly in the sarcomatous UC component. Collectively, a combined analysis of Ki67, PCNA, MCM3, and topoIIα may provide more detailed information of cell-cycle alterations determining the heterogeneity of uterine carcinosarcomas.

Clinico-pathologic characteristics and prognostic factors of ovarian carcinoma with different histologic subtypes - A benchmark analysis of 482 cases

PURPOSE

Ovarian carcinomas (OCX) have traditionally been thought to arise from the ovarian surface epithelium. However, recent (immuno-) histopathological and molecular analyses suggest that OCX consist of morphological subtypes with different epidemiologic features and a varying prognosis.

METHODS

The data of 482 OCX from the Clinical Cancer Registry of Leipzig who were surgically treated between 2000 and 2019 and were evaluated regarding incidence, clinico-pathologic characteristics and prognostic factors. Cases were separated into high-grade and non-high-grade serous tumors. Both groups were analyzed regarding the tumor stage, lymph node involvement, site of origin and prognosis.

RESULTS

The overall incidence for OCX was 17.9. The most common histological subtype was high-grade serous OCX (57.9%; 279/482). Patients with high-grade were significantly older than those with a non-high-grade serous OCX (63.9 versus 58.5 years; p < 0.001), more frequently diagnosed at an advanced stage >pT3 (78.5% (219/279) versus 42.8% (87/203); p < 0.001) and showed a 2.4-fold higher frequency of lymph node metastases (53.4% vs. 21.2%; p < 0.02) with a 4.6-fold higher rate of > 1 cm metastatic deposits (pN1b) within the lymph nodes (14.8% vs. 4.6%; p < 0.02). Irrespective of tumor stage and morphological subtype, the 1- and 5-year overall survival (OAS) was 72.9% and 40.8%, respectively. Patients with high-grade serous OCX showed a shorter 5-year OAS compared to non-high-grade serous OCX (34.1% vs. 57.0%; p 0.001). This association was reproducible in patients with an advanced tumor stage irrespective of the histopathologic tumor type serous OCX (pT3: 32.4% vs. pT1: 75.1%; p 0.001) as well as within high-grade (pT3: 28.7% vs. pT1: 55.5%; p = 0.003) and non-high-grade serous OCX (pT3: 43.0% vs. 80.0%; p 0.001). There were no differences in OAS depending on the site of origin (fallopian tube, ovary, peritoneum) within the two histologic subgroups.

CONCLUSION

OCX cases from a single institution with uniform surgical treatment and a standardized histopathological workup were evaluated. The poor prognostic outcome of patients with high-grade serous compared non-high-grade serous OCX as well as an advanced stage of the disease was confirmed. This study demonstrates for the first time that the histopathological distinction into high-grade serous and non-high-grade serous tumors may be much more prognostically relevant than the site of origin.

Angiogenin and MMP-2 as potential biomarkers in the differential diagnosis of gestational trophoblastic diseases

BACKGROUND

Gestational trophoblastic diseases (GTDs) are characterized by vascular abnormalities of the trophoblast, but their pathogenesis is unknown. Angiogenin (ANG) and matrix metalloproteinase (MMP)-2, which are molecules implicated in the angiogenic process, may play some role in this process.

MATERIAL AND METHODS

We determined ANG and MMP-2 in the placental tissues of 26 patients who had a benign mole (BM), 12 patients with gestational trophoblast neoplasia (GTN) (1 invasive hydatidiform mole, 10 choriocarcinomas, and 1 placental-site trophoblastic tumor), and 28 normal chorionic villi (NCV) subjects using immunohistochemistry staining. We obtained the serum samples from 20 patients with GTDs and 20 early pregnant women and evaluated them by the enzyme linked immunosorbent assay.

RESULTS

ANG expression in GTN (66.7%) and BM (100%) samples were both significantly higher (strong/intermediate staining) than in NCV (60.7%) samples (P < .001). Similarly, the immunoreactivities of MMP-2 in the GTN (66.7%) and BM (80.8%) samples were significantly elevated compared to that of the NCV (57.1%) samples (P < .001). The levels of ANG and MMP-2 in the maternal serum of the GTN group were both significantly higher than those of the control group (P < .001). ANG and MMP-2 expressions were associated with gestation age, clinical stage, and FIGO stage. A positive correlation between ANG and MMP-2 expression was observed (rs = 0.725; P < .01).

CONCLUSION

ANG and MMP-2 levels were significantly elevated in the placental tissues and maternal serum from patients with GTDs. Further studies with more patients may clarify the vascular abnormalities in GTDs and determine potential biomarkers in the differential diagnosis of GTDs.

Concurrent Clostridial Enteritis and Oviductal Adenocarcinoma with Carcinomatosis in an Adult Alpaca (Vicugna pacos)

An adult alpaca (Vicugna pacos) with a history of colic and anorexia was euthanized because of failure to respond to treatment. Macroscopically, pale-tan, multifocal to coalescing, firm nodules and plaques markedly expanded the omentum, mesentery and the parietal and visceral peritoneum of multiple abdominal organs, especially the right oviduct and associated mesosalpinx. Abundant dark-red watery digesta were present in the duodenum and jejunum. Histological evaluation of the right oviduct, abdominal visceral nodules and plaques and mesenteric lymph nodes revealed transmural expansion and replacement by an epithelial malignant neoplasm, comprised of tubules and acini of ciliated columnar cells supported by abundant fibrous connective tissue. Both ovaries were histologically normal. On the basis of the ciliated morphology of the neoplastic cells, the focus on the proximal reproductive tract and the unremarkable ovaries, a reproductive tubal adenocarcinoma with carcinomatosis was diagnosed, with both the endometrium and oviduct considered as the tissues of origin. The prominent ciliated morphology of the neoplastic cells and the classification of human fallopian tube (oviduct) neoplasia lead us to propose oviductal adenocarcinoma with widespread carcinomatosis as the definitive diagnosis. The lamina propria of the small intestine was infiltrated segmentally by lymphocytes, plasma cells and neutrophils, and Clostridium perfringens with beta2 toxin production was identified by polymerase chain reaction in the small intestinal contents. To our knowledge, this is the first report of these two distinct diseases in an alpaca.

Solitary cutaneous metastasis from an ovarian high-grade serous carcinoma at the initial presentation: Cytologic diagnosis of a rare manifestation

Cutaneous metastasis can rarely be the first manifestation of visceral malignancies and is commonly seen in advanced-stage malignancies. It is infrequently seen in patients with ovarian malignancies and may develop either late in the course of the disease or at the initial presentation. Such cases are often associated with poor prognosis, and a prompt, precise tissue diagnosis is essential for appropriate patient management and better clinical outcome. Herein, we present a case of cutaneous metastasis in a young woman with an undiagnosed abdominopelvic mass that was diagnosed as metastatic high-grade serous carcinoma (HGSC) on fine-needle aspiration cytology (FNAC) supplemented by immunocytochemistry (ICC) on the cell block. The index case documents a unique and rare metastatic presentation of ovarian HGSC, as non-Sister Mary Joseph anterior abdominal wall nodule, at the initial presentation. Additionally, it highlights the utility of minimally-invasive FNA combined with ICC in prompt and accurate preoperative diagnosis of an underlying ovarian malignancy.

Diagnostic challenges in the gray-zone lesions of fine-needle aspiration cytology

Fine-needle aspiration cytology (FNAC) is an excellent technique for rapid diagnosis due to its speed, accuracy, and cost-effectiveness. However, there are many gray-zone areas in cytology that needs attention. These lesions in the aspiration cytology can be overcome by applying the selective use of the series of tests. This review discusses the diagnostic challenges in the gray-zone areas in FNAC. It emphasizes the use of selective ancillary techniques to solve the problems in this area.

Analysis of factors affecting the diagnostic yield of image-guided percutaneous core needle biopsy for peritoneal/omental lesions

PURPOSE

To evaluate the diagnostic yield, safety, and factors associated with the diagnostic yield of percutaneous core needle biopsy (PNB) for peritoneal/omental lesions.

METHODS

Consecutive 297 patients (67 men, 230 women; median age, 64 years [range 15-87]) who underwent a PNB for 311 peritoneal/omental lesions at a single center from April 2010 to March 2020 were evaluated retrospectively. The preprocedural CT findings, diagnostic yield, sensitivity, specificity, PPV, NPV, technical success rate, and adverse events were analyzed. Surgical or clinical diagnosis with follow-up was the diagnostic reference standard. Adverse events were evaluated using the Society of Interventional Radiology guidelines.

RESULTS

The median anteroposterior (AP) diameter and CT value of the target lesion were 24 mm (range 5-78) and 46 HU (range - 75 to 140), respectively. Ascites was interposed on the puncture route in 106 patients (34.1%). The technical success rate was 100%. The diagnostic yield, sensitivity, specificity, PPV, and NPV were 93.9%, 93.8%, 100%, 100%, and 20.8%, respectively. Minor complications were observed following five procedures (1.6%). The diagnostic yield was lower for fat-dominant lesions than for other lesions (82.6% vs. 95.8%, p = 0.002). The diagnostic PNB group had a greater AP diameter than did the non-diagnostic PNB group (27.3 ± 13.0 vs. 20.7 ± 8.4 mm, p = 0.037).

CONCLUSION

PNB for peritoneal/omental lesions provided a sufficiently high diagnostic yield and minimal adverse events. Lesions with a greater AP diameter and a higher density on CT would provide more diagnostic specimens from this technique.

Comparative protective effects of N-acetylcysteine and melatonin against obesity-induced testicular dysfunction in rats

N-acetylcysteine (NAC) and melatonin were reported to exert protective effects on testicular tissues. Thus, this study aimed to determine which of these is more efficient against obesity-induced testicular dysfunction in albino rats. A total of 32 adult male rats (195 ± 10 g) were divided into four groups: control, obese rats fed a high-fat diet (HFD), HFD+NAC (150 mg/kg per day, i.p.) and HFD+melatonin (10 mg/kg per day, i.p.), for 5 weeks. Testes and epididymis were weighed. Lipid profile, pituitary-testicular hormones, tumor necrosis factor α (TNFα), epididymal sperm parameters, testicular oxidant-antioxidant system, testicular and the epididymal histopathology and immunohistochemical localization for androgen receptors (AR) and Bax reaction were analyzed. Administration of NAC or melatonin significantly improved the lipid parameters, gonadal hormones, TNFα level, sperm count and abnormal morphology, oxidant-antioxidant system and the absolute testicular and epididymal mass with an enhancement of testicular architecture, AR expression and apoptosis as compared with that in the obese group. Additionally, as compared with the NAC group, the melatonin group had significantly reduced body mass index, total cholesterol, triglyceride, and TNFα and increased testosterone, sperm count, motility, superoxide dismutase activity, mitigated histomorphometrical changes, Bax expression, and increased testicular AR expression. Therefore, melatonin was more efficient than NAC in affording fortification against HFD-induced testicular dysfunction.

Ultrasound-guided fine needle aspiration of ovarian masses: Assessment of diagnostic accuracy and risk stratification using a categorical reporting system

INTRODUCTION

The present study was undertaken to assess the accuracy of fine needle aspiration cytology (FNAC) and cell-block immunocytochemistry, and to estimate the risk of malignancy, using a categorical reporting system, in the diagnosis of ovarian masses.

METHODS

This was a 5-year retrospective study of FNAs of ovarian masses. The cytological diagnoses were categorised as inadequate, non-neoplastic, benign neoplasms, indeterminate for malignancy, suspicious for malignancy and malignant neoplasms. The cytology was correlated with the corresponding histopathology to assess the diagnostic accuracy and risk of malignancy associated with each diagnostic category.

RESULTS

Of a total of 66 703 FNAs performed during the study period, 580 (0.9%) were performed on ovarian masses. Of these, 40 (6.9%) were reported as non-neoplastic; 76 (13.1%) as benign neoplasms; 14 (2.4%) as indeterminate for malignancy, 48 (8.3%) as suspicious for malignancy, 337 (58.1%) as malignant neoplasms and 65 (11.2%) as inadequate for interpretation. Immunocytochemistry (ICC) was performed on 99 (17%) aspirates. Subsequent histopathology was available in 208 (35.8%) cases. On cyto-histopathological correlation, 183 (88%) were concordant and 25 (12%) were discordant. The overall sensitivity, specificity, positive and negative predictive values and diagnostic accuracy for diagnosing ovarian malignancy were 88.4%, 85.7%, 96.8%, 60.0% and 88% respectively. Risk of malignancy for each category was 80%, 0%, 4.5%, 66.7%, 88.5% and 98.5% respectively.

CONCLUSIONS

Ultrasound-guided FNAC has high specificity and diagnostic accuracy for preoperative diagnosis of ovarian malignancies and hence is a valid diagnostic procedure in certain clinical situations. Reporting using a categorical system imparts uniformity and also provides the clinicians with an associated risk of malignancy to guide further management.

Immunohistochemical characterization of Sertoli cell tumour in an adult bull

The present study reports a case of Sertoli cell tumour and its immunohistochemical characterization using pancytokeratin, vimentin and p53 in an adult bull. A six and a half years old bull was presented in the Department of Veterinary Clinical Complex, College of Veterinary Sciences of the University with the history of gradual enlargement of both testes since last one and a half years. Grossly, both testes appeared hard and firm. Microscopically, haematoxylin and eosin stained tissue sections revealed neoplastic Sertoli cells arranged in groups as islands/broad sheets separated by connective tissue stroma. Neoplastic cells showed indistinct cytoplasmic boundary, cytoplasmic vacuolation and enlarged pleomorphic hyperchromatic nuclei with prominent nucleoli. Neoplastic cells were positive for p53 and vimentin and negative for pancytokeratin. Moderate to strong p53 nuclear immunoreactivity was noticed in most of the neoplastic cells indicating role of p53 tumour suppressor gene in tumourogenesis. Vimentin immunopositivity was observed in cytoplasm of neoplastic cells but no immunoreactivity for pancytokeratin was noticed. The application of pancytokeratin and vimentin antibodies in present case provided important information for differential diagnosis between Sertoli cell tumour and seminoma.

Histological and immunohistochemical characterization of 17 gonadal tumours in koi carp (Cyprinus carpio koi)

Reports on abdominal tumours in koi carp are scarce and most are from the gonads. Their histological diagnosis is challenging due to the occurrence of mixed populations of neoplastic cells and the few availability of cross-reactive antibodies in fish tissues. The present study aims to provide a histopathological characterization of seventeen gonadal tumours, enriched by a wide antibody panel (vimentin, CD117, placental alkaline phosphatase-PLAP, AE1/AE3 cytokeratin, E-cadherin, proliferating cell nuclear antigen-PCNA, müllerian-inhibiting substance-MIS, GATA4 and Inhibin-α) applied on whole and tissue microarray (TMA) sections. Abdominal enlargement was associated with tumours filling 30%-80% of the abdominal cavity; frequently, the gonads had been completely replaced by neoplastic tissue. Twelve cases were characterized as sex cord-stromal tumours (SCSTs), three as germ cell tumours (GCTs), one as mixed germ cell sex cord-stromal tumour (MGCSCST) and one as carcinoma. By immunohistochemistry, PLAP enabled confirmation of GCTs, ovarian carcinoma and the objective identification of a further cell component in 8 out of the 12 SCSTs that were reclassified as mixed tumours. The use of an immunohistochemical panel can help in refining the histological diagnosis, but the morphological diagnosis still represents the main tool for the characterization of these tumours in koi carp.

Metastatic Mixed Germ Cell Tumour with Embryonal Carcinoma and Choriocarcinoma in a Female Eurasian Harvest Mouse (Micromys minutus)

Mixed germ cell tumours occur rarely in veterinary species. This report describes a case of metastatic mixed germ cell tumour in a female Eurasian harvest mouse (Micromys minutus). The tumour was extensive in one ovary and the uterus, and was characterized by two distinct tumour cell populations with features typical of embryonal carcinoma (EC) and choriocarcinoma (CC). Metastases of CC to the lungs and liver were observed. The exact origin of the CC was unclear, but the possibility of a non-gestational CC is favoured, given the context of a mixed germ cell tumour and lack of p53 expression. EC diagnosis was confirmed by immunohistochemical labelling of CD30 and lack of immunoreactivity for c-Kit. In addition, membranous β-catenin expression was present in the EC component, indicating an inactive Wnt/β-catenin pathway, which is required for the maintenance of pluripotency.

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

OBJECTIVES

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

MATERIAL AND METHODS

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

RESULTS AND CONCLUSIONS

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

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

INTRODUCTION

Serous borderline tumors (SBT) are the most common subtype of ovarian borderline tumors with excellent clinical course. However, they can recur or progress to low-grade serous carcinoma (LGSC) in a small proportion of the cases. Beside BRAF and KRAS mutations, copy number alterations (CNA), particularly loss of chromosome 9p21 locus which results in deletion of genes CDKN2A and MTAP, have been suggested to be involved in disease progression. MTAP immunohistochemistry recently has been introduced for mesothelioma as a reliable surrogate marker for the homozygous deletion of chromosome 9p21 locus. Therefore, in the current study, we aimed to evaluate the MTAP loss of expression in serous borderline tumors and low-grade serous carcinomas to identify if it can be used as a marker for prognosis and progression.

METHOD

Eighty-four total cases of ovarian serous lesions, including 21 cases of serous cystadenomas, 21 cases of serous borderline tumors, 12 cases of low-grade serous carcinomas and 30 cases of high-grade serous carcinomas were selected. MTAP immunohistochemistry was performed on the representative blocks and cytoplasmic staining was used for interpretation. The cases were labeled as positive (retained) if MTAP showed cytoplasmic granular staining and negative (loss of expression) if negative cytoplasmic staining was observed in the presence of positive internal control.

RESULT

Ten of 21 cases of serous borderline tumors showed loss of MTAP expression (48%). Among those, 7 cases were bilateral, 2 cases had micropapillary features, one case had supraclavicular and cervical lymph node involvement by serous borderline tumor and 2 cases had progression to low-grade serous carcinoma, including one of micropapillary tumors. Also 8 out of 12 cases of LGSCs showed MTAP loss of expression (66%). Only 4 of 30 cases of high-grade serous carcinomas (13%) and none of the serous cystadenoma cases showed loss of expression of MTAP.

CONCLUSION

To our knowledge, this is the first description of MTAP immunohistochemistry in serous borderline tumors and low-grade serous carcinomas. Our study was limited due to small sample size. However, it showed an association between MTAP loss of expression and adverse clinical behavior in ovarian serous borderline tumors. This supports the role for further investigations in larger series to evaluate the role of MTAP stain as a prognostic marker in these neoplasms.

Small Cell Carcinoma of the Ovary: Clinicopathologic and Immunohistochemical Analysis of 7 New Cases of a Rare Malignancy

BACKGROUND

Small cell carcinoma of ovary (SCCO) is extremely rare. Two types of SCCO are recognized, the pulmonary type (SCCOPT) and the hypercalcemic type (SCCOHT). Establishing an accurate diagnosis is challenging, owing to its rarity and paucity of data describing the distinctive histopathologic and immunohistochemical (IHC) features.

METHODS

This was a retrospective study conducted over a period of 4 years. All cases reported as SCCO on histopathology were retrieved. All the available clinical, histopathological, and IHC features were studied in detail.

RESULTS

A total of 7 cases of SCCO were diagnosed during the study period. There were 4 cases of SCCOPT and 3 cases of SCCOHT and with mean age of 57.25 and 22 years, respectively. All the cases presented as stage IV disease. Among the SCCOPT cases, 3 showed bilateral involvement with 1 showing concurrent uterine endometrioid adenocarcinoma. Microscopy revealed small hyperchromatic cells with brisk mitosis and multifocal necrosis. On IHC, these were consistently positive for chromogranin, CD56, and synaptophysin. All the SCCOHT cases showed unilateral involvement. Microscopically, in addition to small hyperchromatic cells, larger "rhabdoid" tumor cells were also seen. On IHC, chromogranin was negative, with positivity for vimentin and epithelial membrane antigen. The expression of SMARCA4/BRG1 was lost while SMARCB1/INI1 was retained in all cases. All of these patients developed recurrence and died due to disease progression despite treatment.

CONCLUSIONS

SCCO is an extremely infrequent ovarian malignancy with poor prognosis. Knowledge about its characteristic features is important for accurate tissue diagnosis and appropriate management.

A Comprehensive Review of Biomarker Use in the Gynecologic Tract Including Differential Diagnoses and Diagnostic Pitfalls

Morphologic (ie, hematoxylin and eosin) evaluation of the Mullerian tract remains the gold standard for diagnostic evaluation; nevertheless, ancillary/biomarker studies are increasingly utilized in daily practice to assist in the subclassification of gynecologic lesions and tumors. The most frequently utilized "biomarker" technique is immunohistochemistry; however, in situ hybridization (chromogenic and fluorescence), chromosomal evaluation, and molecular analysis can also be utilized to aid in diagnosis. This review focuses on the use of immunohistochemistry in the Mullerian tract, and discusses common antibody panels, sensitivity and specificity of specific antibodies, and points out potential diagnostic pitfalls when using such antibodies.

Expression of Wilm’s Tumor Gene (WT1) in Endometrium with Potential Link to Gestational Vascular Transformation

Background: Wilm’s tumor 1 gene (WT1) is a transcription factor with versatile cellular functions in embryonic development, the maintenance of adult tissue functions, and regeneration. WT1 is known to be regulated by progesterone and it is abundantly expressed in endometrium, but its function is unclear. Design: in this observational and descriptive study, WT1 expression was detected by immunohistochemical staining in endometrium of various physiological and pathological conditions. Result: WT1 was detected in endometrial stromal cells and vascular smooth muscle cells, in both proliferative and secretory phases of menstrual cycles. WT1 appeared increased in vascular smooth muscle cells in spiral artery in early pregnancy and it was also detected in regenerative endothelial cells and smooth muscle cells in decidual vasculopathy at term. WT1 expression appeared decreased in endometrial stromal cells in adenomyosis (endometriosis). Conclusion: WT1 potentially links the hormonal effects on endometrial decidualization and may play a role in gestational vascular transformation during pregnancy and restoration after pregnancy.

Well-Differentiated Papillary Mesothelioma with Omental Calcifications: A Case Report and Review of the Literature

BACKGROUND Omental calcifications of the peritoneum are typically small and asymptomatic. However, larger psammomatous bodies that cause symptoms such as abdominal pain and bloating are often associated with tumors such as primary serous papillary carcinoma, mesothelioma, or metastatic ovarian cancer. CASE REPORT We describe omental calcifications in a 68-year-old woman who had been asymptomatic for the last 10 years. The case details the histomorphologic features and immunohistochemical signature of a 4.0×3.5×1.0 cm mass consisting of mature adipose tissue that was surgically removed together with an 8.5×6.5×1.8 cm irregular intra-abdominal/mesenteric mass composed of yellow-red fatty tissue. Microscopic sections contained fat with variable clustered classic/psammomatous calcifications, some with a thin epithelioid periphery, in association with a very focal and subtle papillary surface epithelial/mesothelial proliferation. Tumor cell invasion was not observed during examination. Immunohistochemical staining showed that mesothelial cells in the mass were strongly positive for calretinin and focally positive for EMA, CK903, and vimentin. Strong nuclear positivity for PAX8 was also reported. Additional stains were added in response to this pattern, showing strong positivity for CK8, moderate positivity for BAP1, focal positivity for ER, minimal positivity for CD56, and negativity for CK5/6 and D2-40. Three possible explanations are suggested for the phenomenon observed in the pathology slides: reactive mesothelial hyperplasia, well-differentiated papillary mesothelioma, or serous papillary carcinoma of the peritoneum. CONCLUSIONS Findings suggest that these calcifications are a benign, reactive phenomenon, and that the abundance of psammoma bodies may be related to ongoing crops of papillary mesothelial hyperplasia or benign well-differentiated papillary mesothelioma.

A detailed morphological and immunohistochemical comparison of primary endometrial and tubo-ovarian high-grade serous carcinomas and their corresponding omental metastases

Increasingly, high-grade serous carcinomas (HGSCs) of fallopian tube/ovarian origin are managed initially with neoadjuvant chemotherapy (NACT) and pre-treatment diagnosis is often based upon relatively limited core biopsy and/or cytology specimens. Endometrial HGSC can also present with adnexal and peritoneal metastasis, thus mimicking a primary tubo-ovarian neoplasm, but the role of NACT in these cases is less established. Immunohistochemistry has been considered useful in this distinction but with a wide range of reported findings in the literature. In this study we have examined tumour growth patterns and the expression p16, Ki-67, WT1, PAX2, HER2, ER-α, ER-β, PR, and BAF250a in 18 tubo-ovarian and 14 endometrial HGSCs, comparing the findings in primary and omental sites. Metastatic tubo-ovarian carcinomas demonstrated significantly more varied architectural patterns than metastatic endometrial HGSCs (median 2.5 versus 1). None of the immunohistochemical markers proved completely reliable but only endometrial HGSC were WT1 negative (7/14 metastatic tumours) or demonstrated over-expression of HER2 (2/14 cases). Micropapillary tumour elements more often showed retained PAX2 and WT1 expression, low Ki-67 labelling, and (in endometrial tumours) PR staining. Diverse architectural patterns suggest tubo-ovarian origin in a metastatic HGSC. Immunohistochemical results should be cautiously interpreted, particularly in small specimens.

APC2 is critical for ovarian WNT signalling control, fertility and tumour suppression

BACKGROUND

Canonical WNT signalling plays a critical role in the regulation of ovarian development; mis-regulation of this key pathway in the adult ovary is associated with subfertility and tumourigenesis. The roles of Adenomatous polyposis coli 2 (APC2), a little-studied WNT signalling pathway regulator, in ovarian homeostasis, fertility and tumourigenesis have not previously been explored. Here, we demonstrate essential roles of APC2 in regulating ovarian WNT signalling and ovarian homeostasis.

METHODS

A detailed analysis of ovarian histology, gene expression, ovulation and hormone levels was carried out in 10 week old and in aged constitutive APC2-knockout (Apc2-/-) mice (mixed background). Statistical significance for qRT-PCR data was determined from 95% confidence intervals. Significance testing was performed using 2-tailed Student's t-test, when 2 experimental cohorts were compared. When more were compared, ANOVA test was used, followed by a post-hoc test (LSD or Games-Howell). P-values of < 0.05 were considered statistically significant.

RESULTS

APC2-deficiency resulted in activation of ovarian WNT signalling and sub-fertility driven by intra-ovarian defects. Follicular growth was perturbed, resulting in a reduced rate of ovulation and corpora lutea formation, which could not be rescued by administration of gonadotrophins. Defects in steroidogenesis and follicular vascularity contributed to the subfertility phenotype. Tumour incidence was assessed in aged APC2-deficient mice, which also carried a hypomorphic Apc allele. APC2-deficiency in these mice resulted in predisposition to granulosa cell tumour (GCT) formation, accompanied by acute tumour-associated WNT-signalling activation and a histologic pattern and molecular signature seen in human adult GCTs.

CONCLUSIONS

Our work adds APC2 to the growing list of WNT-signalling members that regulate ovarian homeostasis, fertility and suppress GCT formation. Importantly, given that the APC2-deficient mouse develops tumours that recapitulate the molecular signature and histological features of human adult GCTs, this mouse has excellent potential as a pre-clinical model to study ovarian subfertility and transitioning to GCT, tumour biology and for therapeutic testing.

Neoadjuvant therapy in gynaecological malignancies: What pathologists need to know

In recent times, there has been a growing tendency to treat advanced gynaecological malignancies with neoadjuvant chemotherapy (NACT), with the goal of reducing tumour volume and enhancing operability resulting in optimal cytoreduction. This approach is used in particular for patients with advanced high-grade serous carcinoma of the ovary, fallopian tube or peritoneum. Pathology plays a crucial role in the management of these patients, both before and after NACT. Prior to initiation of NACT, a biopsy should be performed, usually of the omental cake, to confirm that a malignancy is present, to identify the site of origin of the tumour and to type and grade the tumour. Histopathologists must be aware of the resultant morphological effects of NACT when examining specimens following interval cytoreduction surgery. Tumour typing and grading, and even the identification of residual neoplasia, are particular challenges. Immunohistochemistry, when used judiciously, can be a useful adjunct in certain scenarios. A pathological assessment of the response to chemotherapy, and the pathological stage should be provided in the pathology report, as these may inform prognosis and subsequent management. We present a comprehensive overview of the relevant clinical and pathological aspects pertaining to NACT for gynaecological malignancies for the practicing surgical pathologist.

Immunophenotypic profile as a predictor of prognosis in advanced ovarian carcinoma

Although proteomic profiles for ovarian epithelial carcinoma (OECa) have been widely investigated, no single marker or set of predictors has been clinically implemented mainly because their reliability and validity have not yet been well established. To establish immunohistochemical (IHC) panels for prognosis prediction of OECa for use in daily pathology practice, the expression patterns of 12 IHC markers, p53, HNF-1β, ARID1A, estrogen receptor-α, progesterone receptor, vimentin, PTEN, PIK3CA, WT1, left-right determination factor, β-catenin, and Ki-67 were investigated using 282 OECas. Hierarchical clustering analysis revealed 7 major immunoprofile groups (IPGs I-VII) that could be used to categorize OECa tumors independent of histotypes. Based on the results of the cluster analysis and protein expression statuses, we further demonstrated the effective classification of OECa tumors into simplified immunoprofile panels using only 4 IHC markers including HNF-1β, p53, ARID1A, and WT1. The tumors in IPG VII with HNF1β+/p53+/ARID1A+ immunophenotype demonstrated a significantly worse overall survival and progression-free survival as compared with the other IPGs. Multivariate Cox regression analysis also revealed that the immunophenotype (HNF1β+/p53+/ARID1A+) and clinical stage were significant and independent prognostic factors for overall survival and progression-free survival in advanced OECa. In conclusion, we identified immunoprofiles in OECa using a panel of 4 IHC markers, which could identify tumors by the immunophenotype that is associated with the most unfavorable prognosis and thus facilitate prognosis prediction of advanced OECa.

Systemic Treatment of Metastatic/Recurrent Uterine Leiomyosarcoma: A Changing Paradigm

The treatment of metastatic and recurrent uterine leoimyosarcoma (uLMS) has evolved rapidly in the past several years. Leoimyosarcoma is extremely aggressive and responds poorly to traditional chemotherapeutics. Recent regulatory approval of novel treatment options has significantly expanded the therapeutic armamentarium, and the addition of these therapies has challenged clinicians to select and optimally sequence these new compounds. Additionally, the potential role of immunotherapy is being assessed in current uLMS clinical trials. Given the increasing number of agents available both in the U.S. and globally, a treatment template that addresses optimal sequencing based upon expert consensus would be useful. Current guidelines, although listing various options, lack granularity by line of therapy. Most patients with leiomyosarcoma, even in early stage, are treated with surgery followed by adjuvant chemotherapy despite uLMS being relatively chemoresistant. Adjuvant chemotherapy often includes the combination of gemcitabine and docetaxel with or without doxorubicin in first-line systemic therapy, but these cytotoxic agents only provide patients with advanced disease a 5-year survival <30%. This review will focus on examination of current guidelines and consensus building for optimal sequencing of systemic therapies for advanced or recurrent uLMS. Critical ongoing studies investigating novel approaches including immunotherapeutics and genetic alterations also will be discussed. IMPLICATIONS FOR PRACTICE: Recent regulatory approval of novel treatment options has significantly expanded the therapeutic armamentarium, and the addition of these therapies has challenged clinicians to select and optimally sequence these compounds. This review will focus on examination of current guidelines and consensus building for optimal sequencing of systemic therapies for advanced or recurrent uterine leoimyosarcoma.

An update on the use of immunohistochemistry and molecular pathology in the diagnosis of pre-invasive and malignant lesions in gynecological oncology

OBJECTIVE

One of the most common challenges in everyday clinical practice of gynecological oncology is to identify the type and the primary origin of a tumor. This is a crucial step in the management, treatment, prognosis, and survival of patients suffering from a gynecological malignancy. Immunohistochemistry has been widely adopted over the last three decades in pathology laboratories all over the world. Recent advances in our understanding of the differentiation of gynecological tumors based on immunohistochemical expression have resulted in use of immunohistochemistry as a major diagnostic tool in gynecology, for precise tumor classification. More recently, advances in molecular pathology, have taken this disease sub-classification further resulting in more effective personalised treatment regimens. The aim of this review is to provide clinicians with up to date information on the various immunohistochemical and molecular tests used in the diagnosis of gynecological malignancies of the female genital tract and an understanding of how to interpret them.

METHODS

We performed a review of the current literature including review articles, original research articles, and guidelines on various immunohistochemical markers and molecular techniques which are used for the differential diagnosis of gynecologic malignancies.

CONCLUSIONS

Immunohistochemistry is useful as an objective means for improved diagnostic reproducibility, accuracy, and precise classification in cases where the diagnosis with histochemical stains is inconclusive, providing a more reliable estimate of clinical outcomes. The diagnosis, in some cases, can be further refined by the use of molecular techniques leading to personalised medical treatments.

[Endometrial dysfunction caused by chronic endometritis: сlinical and morphological aspects]

AIM

to determine the clinical and morphological aspects of endometrial dysfunction caused by chronic endometritis (CE).

SUBJECTS AND METHODS

The study included 239 reproductive-aged patients: 93 were examined for abnormal uterine bleeding; 37 patients of them had a history of miscarriage and secondary infertility, 17 patients had primary infertility (Group 1). The remaining 105 patients with infertility were examined for future in vitro fertilization (Group 2). A comparison group consisted of 41 patients with normal menstrual cycles and reproductive function across the cycle, who had separate diagnostic curettage before forthcoming surgery for uterine myoma. All the women in Groups 1 and 2 underwent standard clinical and morphological investigations, histopathological examination of the material obtained during hysteroscopy with separate diagnostic curettage (Group 1), and aspiration biopsy (Group 2) with the sections being stained with hematoxylin and eosin and by Mallory's method. Immunohistochemical diagnosis was used to assess endometrial receptivity to steroid hormones and glycodelin. Antibodies against CD4, СD8, and CD20 were employed to study local immunity.

RESULTS

In Group 1, 52 (55.9%) of the 93 patients admitted to hospital for abnormal uterine bleeding were found to have CE on the basis of a morphopathological examination of the material after separate diagnostic study. In Group 2, CE was established in 59 (56.9%) of the 105 patients after postmortem examination. The patients with CE had a history of reproductive significant infections, such as Chlamydia, Trichomonas, Ureaplasma Mycoplasma, cytomegalovirus, papillomavirus infections, genital herpes, genital candidiasis, and bacterial vaginosis. The CE groups showed functional disorders of the endometrial glandular and surface epithelium. In the middle stage of proliferation, the expression of glycodelin in the glandular epithelial cells was detected to be moderate to strong in 83.3%. During the periovulatory period, no secretion of glycodelin is of fundamental importance for the regulation of reproductive function because this protein has contraceptive activity, by blocking the binding of sperm to the zona pellucida. Accordingly, endometrial glycodelin production during the proliferative phase, which has been identified by the authors in patients with CE, may be one of the pathogenic mechanisms for the development of infertility. In addition, the patients in Groups 1 and 2 compared with those in the comparison group were noted to have a decrease in CD4 cell counts with a simultaneous increase in CD8 expression and a reduction in CD20 levels, especially in Group 2.

CONCLUSION

The patients with SE were identified to have endometrial dysfunction characterized by lower reception to steroid hormones, impairment in glycodelin secretion, retardation in the development of pinopods and in the phase of the menstrual cycle, and local immunity disorders. The above endometrial changes should be taken into account in the pregravid preparation of patients with CE.

Clinically actionable mutation profiles in patients with cancer identified by whole-genome sequencing

Next-generation sequencing (NGS) efforts have established catalogs of mutations relevant to cancer development. However, the clinical utility of this information remains largely unexplored. Here, we present the results of the first eight patients recruited into a clinical whole-genome sequencing (WGS) program in the United Kingdom. We performed PCR-free WGS of fresh frozen tumors and germline DNA at 75× and 30×, respectively, using the HiSeq2500 HTv4. Subtracted tumor VCFs and paired germlines were subjected to comprehensive analysis of coding and noncoding regions, integration of germline with somatically acquired variants, and global mutation signatures and pathway analyses. Results were classified into tiers and presented to a multidisciplinary tumor board. WGS results helped to clarify an uncertain histopathological diagnosis in one case, led to informed or supported prognosis in two cases, leading to de-escalation of therapy in one, and indicated potential treatments in all eight. Overall 26 different tier 1 potentially clinically actionable findings were identified using WGS compared with six SNVs/indels using routine targeted NGS. These initial results demonstrate the potential of WGS to inform future diagnosis, prognosis, and treatment choice in cancer and justify the systematic evaluation of the clinical utility of WGS in larger cohorts of patients with cancer.

Unraveling endometriosis-associated ovarian carcinomas using integrative proteomics

Background: To elucidate potential markers of endometriosis and endometriosis-associated endometrioid and clear cell ovarian carcinomas using mass spectrometry-based proteomics.

Methods: A total of 21 fresh, frozen tissues from patients diagnosed with clear cell carcinoma, endometrioid carcinoma, endometriosis and benign endometrium were subjected to an in-depth liquid chromatography-tandem mass spectrometry analysis on the Q-Exactive Plus. Protein identification and quantification were performed using MaxQuant, while downstream analyses were performed using Perseus and various bioinformatics databases.

Results: Approximately 9000 proteins were identified in total, representing the first in-depth proteomic investigation of endometriosis and its associated cancers. This proteomic data was shown to be biologically sound, with minimal variation within patient cohorts and recapitulation of known markers. While moderate concordance with genomic data was observed, it was shown that such data are limited in their abilities to represent tumours on the protein level and to distinguish tumours from their benign precursors.

Conclusions: The proteomic data suggests that distinct markers may differentiate endometrioid and clear cell carcinoma from endometriosis. These markers may be indicators of pathobiology but will need to be further investigated. Ultimately, this dataset may serve as a basis to unravel the underlying biology of the endometrioid and clear cell cancers with respect to their endometriotic origins.

A Comprehensive Evaluation of Special AT-rich Sequence-binding Protein 2 (SATB2) Immunohistochemical Staining in Mucinous Tumors From Gastrointestinal and Nongastrointestinal Sites

Special AT-rich sequence-binding protein 2 (SATB2) is an accurate marker for conventional colorectal carcinoma (CRC), although its sensitivity and specificity in mucinous tumors from the colon and other sites remains unknown. The objective of this study is to evaluate the accuracy of SATB2 expression detected by immunohistochemical assay, as a marker of primary CRC in mucinous adenocarcinomas. SATB2 immunohistochemical stains were performed on whole sections from 63 conventional CRCs (controls), 47 mucinous CRCs (mCRC), and 182 noncolorectal mucinous tumors. SATB2 intensity was scored as 1 to 3 based on the estrogen receptor/progesterone receptor grading system, and the percent positive cells was scored in broad categories as follows: 0 (negative)≤5%, 1=5% to 49%, 2≥50%. An optimal sensitivity/specificity pairing (83% and 95%, respectively) was achieved in the mCRCs when the additive intensity and percent score was ≥3 (ie, intensity score+percent score=total score). Defining this total score (histologic score/"H score") as a "positive" result, the sensitivity of SATB2 for conventional CRC was 98% (62/63) versus 83% (39/47) for mCRCs (P=0.02); whereas 5% (9/182) of all noncolorectal mucinous tumors were considered positive. SATB2 especially demonstrated reduced specificity when applied to mucinous gastroesophageal and breast carcinomas, which showed significant expression in 27% and 9% of cases, respectively. In summary, SATB2 is a less sensitive marker of colorectal origin in mCRC compared with conventional CRC and shows significantly reduced specificity in mucinous gastroesophageal and breast primaries.

Endometriosis-associated ovarian neoplasia

This article reviews the most relevant pathological and molecular features of ovarian tumours that are associated with endometriosis. Endometriosis is a common condition, affecting 5-15% of all women, and it has been estimated that 0.5-1% of cases are complicated by neoplasia. The most common malignant tumours in this setting are endometrioid adenocarcinoma and clear cell adenocarcinoma, each accounting for approximately 10% of ovarian carcinomas in Western countries. A minority of cases are associated with Lynch syndrome. These carcinomas are often confined to the ovaries at presentation in which case they have relatively favourable outcomes. However, high-stage tumours, particularly clear cell carcinomas, generally have a poor prognosis and this partly reflects relative resistance to current treatment. Histological diagnosis is straightforward in the majority of cases but some variants, for example endometrioid carcinomas with sex cord-like appearances or oxyphil cells, may create diagnostic difficulty. Similarly, clear cell carcinomas can show a range of architectural and cytological patterns that overlap with other tumours, both primary and metastatic, involving the ovaries. Endometriosis-associated borderline tumours are less common, and they often show mixed patterns of differentiation (seromucinous tumours). Atypical endometriosis may represent an intermediate step in neoplastic progression and some of these lesions demonstrate immunohistological and molecular alterations similar to those observed in endometriosis-related tumours. ARID1A mutations are relatively common in all of these tumours, but each has additional characteristic molecular alterations which are likely to be of increasing clinical relevance as targeted therapies are developed. Less is known of the pathogenesis of rarer endometriosis-associated ovarian tumours including endometrioid stromal sarcoma, mesodermal (Müllerian) adenosarcoma, and carcinosarcoma. This article also briefly reviews the issue of synchronous endometrioid carcinomas of the endometrium and the ovary, including the most recent developments on pathogenesis.

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

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