Morphologic and Immunocytochemical Features of High-Grade Serous Carcinoma of Ovary in Ascitic Fluid Effusion and Fine-Needle Aspiration Cytology

Reevaluation of ovarian cyst fine-needle aspiration cytology: A 10-year institutional experience

OBJECTIVES

Fine-needle aspiration (FNA) of ovarian cyst fluid remains useful for certain clinical circumstances despite low sensitivity and potential safety concerns. The current study aimed to reevaluate the performance of ovarian cystic fluid cytology following American College of Obstetricians and Gynecologists guidelines using a single-institution cohort.

METHODS

A total of 507 ovarian cyst FNA cases from 2013 to 2023 were reviewed. Patients' demographics and clinical and radiologic information were collected through the electronic database. The performance was calculated using corresponding surgical pathology diagnosis as the gold standard.

RESULTS

Overall, cytologic diagnoses were nondiagnostic (ND), negative for malignancy (NFM), atypical (ATY), suspicious for malignancy (SFM), and malignant (M) in 5 (1.0%), 478 (94.3%), 14 (2.7%), 2 (0.4%), and 8 (1.6%) cases, respectively. Among 349 specimens (68.8%) that had a corresponding surgical pathology, the rate of malignancy (including borderline tumors) was 1.2% (4 of 325) in NFM, 72.7% in ATY (8 of 11), and 100% in both SFM (2 of 2) and M (8 of 8) specimens. Considering NFM and ATY as negative results and SFM and M as positive results, overall, the sensitivity of ovarian cystic fluid cytology was 45.4% and the specificity was 100%.

CONCLUSIONS

As an uncommon test, ovarian cystic fluid cytology has moderate sensitivity and high specificity. Despite limitations, ovarian cystic FNA cytology remains a valuable diagnostic tool in certain aspects.

Diagnostic roles of PAX8 immunohistochemistry in ovarian tumors

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Cytopathological assessment is an accurate method for identifying immunophenotypic features and BRCA1/2 mutations of high-grade serous carcinoma from ascites

BACKGROUND

High-grade serous carcinoma (HGSC) is the most common and aggressive type of ovarian cancer, and it is often associated with ascites at presentation. The objective of this study was to evaluate the accuracy of cytopathology to identify immunophenotypic features of HGSC and BRCA1/2 mutations from ascites.

METHODS

The study included 45 patients with histologically confirmed primary HGSC and malignant ascites. Immunocytochemistry (ICC) staining for PAX8, WT1, P53, P16, and Ki-67 was performed on cytospins and cytoblocks prepared from ascites. Next-generation sequencing (NGS) was used to detect germline/somatic BRCA1/2 mutations in the ascites. Both ICC and NGS results were compared with immunohistochemistry (IHC) and NGS results from tissue blocks of primary tumor. Cronbach α and χ² statistics, respectively, were used.

RESULTS

ICC/IHC results for PAX8, WT1, P53, and P16 showed good reliability between cytospins, cytoblocks, and tissue blocks (α > 0.75), whereas poor reliability and significant differences were observed for Ki-67 between ascites and tissue blocks (α < 0.26; p < .001 [Kruskal-Wallis]). For germline BRCA1/2 mutations, 100% concordance was confirmed, but only 14% concordance was confirmed for somatic mutations.

CONCLUSIONS

These results demonstrate that cytopathology is an accurate method for identifying immunophenotypic features of HGSC and detecting germline BRCA1/2 mutations from ascites. However, further investigation is required for assessing the proliferation activity of HGSC in ascites and for detecting somatic BRCA1/2 mutations.

Cytohistologic immunohistochemical correlation of epithelial tubo-ovarian neoplasms: Can cell blocks substitute for tissue?

BACKGROUND

Cytologic specimens often represent the initial diagnostic material for tubo-ovarian neoplasms resulting from therapeutic paracentesis for patients presenting with high-volume ascites. However, subtyping and immunohistochemical (IHC) characterization, which have implications in preoperative management and downstream ancillary testing, are not routinely performed in many institutions. This study aims to perform cytohistologic correlation of commonly used IHC stains to establish their reliability in peritoneal fluids/washing specimens.

METHODS

A retrospective search of the laboratory information systems was performed to identify peritoneal fluid/washing specimens involved by borderline or malignant epithelial tubo-ovarian neoplasms and concurrent/subsequent surgical resection specimens. Cell blocks and tissue were stained for PAX8, WT-1, p53, p16, Napsin-A, estrogen receptor, and progesterone receptor, and staining between cytological and surgical specimens was compared.

RESULTS

A total of 56 case pairs were included, with the following final diagnoses on histological examination: 37 high-grade serous carcinomas, eight clear cell carcinomas, one endometrioid adenocarcinoma, two low-grade serous carcinomas, and eight serous borderline tumors. There was perfect cytohistologic correlation for PAX8 (Lin's concordance correlation coefficient [LINCCC] = 1.00) and WT-1 (LINCCC = 1.00), substantial/good correlation for p53 (LINCCC = 0.96), p16 (LINCCC = 0.93), napsin-A (LINCCC = 0.91) and ER (LINCCC = 0.77), and moderate correlation for PR (LINCCC = 0.54).

CONCLUSIONS

Immunohistochemical correlation between peritoneal fluid and surgical resection specimens for tubo-ovarian neoplasms is high. Common subtypes of tubo-ovarian carcinomas can be reliably distinguished on fluids using IHC.

Decoding the primary tumor origin in carcinomatous serous effusions by immunocytochemistry

INTRODUCTION

Malignant effusions are commonly encountered in day-to-day cytology practice. Determining the primary site of malignancy in carcinomatous effusions is a Herculean task. Cytology coupled with immunocytochemistry is often found helpful in this context.

MATERIALS AND METHODS

This study was undertaken to evaluate diagnostic utility of immunocytochemistry (ICC) on the sections from cell blocks (CBs) to detect the primary site of origin in metastatic carcinomatous effusions. To determine the origin of the primary tumor, TTF1 (lung), PAX-8 (ovary), CDX2 (colo-rectal), GATA3 (breast), and CK19 (pancreaticobiliary) were employed depending on the clinical and radiological findings, and serum tumor markers.

RESULTS

A total of 13,459 serous effusion samples were received for cytological evaluation from January 2017 to December 2021 of which 2708 (20.1%) were carcinomatous effusions. Out of these, 1044 (38.5%), 1611 (59.5%), and 53 (2.0%) were from pleural, peritoneal and pericardial cavities, respectively. Of these, majority were adenocarcinoma. ICC was done in 309 (11.4%) cases. Ovary was the most common primary site in 179 (57.9%) cases, followed by lung (75, 24.3%), pancreaticobiliary (12, 3.9%), colo-rectal (8, 2.6%), breast (6, 1.9%), prostate (2, 0.6%) and kidney (1, 0.3). Lung was the commonest primary site in pleural (67/113, 59.3%) and pericardial (6/8, 75%) effusions. Ovary (168/188, 89.4%) was the most common primary responsible for carcinomatous effusions in the peritoneal cavity. However, in 17 (5.5%) cases, the exact primary site could not be established.

CONCLUSIONS

Judicious and methodical use of ICC on CB helps identify the primary site of the tumor in most carcinomatous effusions. This is of immense help to the treating clinician in directing appropriate therapy.

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.

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.

Educational Case: High-Grade Serous Carcinoma of the Ovary

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, seehttp://journals.sagepub.com/doi/10.1177/2374289517715040.¹.

Application of Indian Academy of Cytologists Guidelines for Reporting Serous Effusions: An Institutional Experience

Background:

Recently, the Indian Academy of Cytologists (IAC) has published the guidelines for interpretation and reporting of serous effusions. Till date, there are no studies on its applicability.

Aims:

The present study was carried out to assess the feasibility of applying the IAC reporting categories to effusions, determine the frequency, and provide an estimate of the risk of malignancy (ROM) for individual diagnostic categories.

Materials and Methods:

All cases of serous effusion fluids reported in the year 2019 were retrieved from the archives and reassigned as per the IAC diagnostic categories. The clinical and histopathological follow-up information was obtained wherever possible.

Results:

A total of 1340 effusion samples were received from 1085 patients. There were 561 (51.7%) males and 524 (48.3%) females. Majority were pleural (1066, 79.5%), followed by peritoneal (187, 14%) and pericardial (87, 6.5%) effusions. The age ranged from 7 months to 92 years. There were 35 (2.6%) samples in category 1 (non-diagnostic), 954 (71.2%) in category 2 (benign), 17 (1.3%) in category 3 (atypical), 59 (4.4%) in category 4 (suspicious for malignancy) and 275 (20.5%) in category 5 (malignant). The estimated ROM in serous effusion samples was 20% for category 1, 16.7% for category 2, 50% for category 3, 94.4% for category 4 and 100% for category 5.

Conclusions:

The categorization of serous effusion cytology samples as per the IAC diagnostic categories and as per the reporting format developed by the IAC is feasible and the management recommendations are mostly appropriate.