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.

Preclinical and Clinical Evaluation of Magnetic-Activated Cell Separation Technology for CTC Isolation in Breast Cancer.

Circulating tumor cell (CTC) count is an independent prognostic factor in early breast cancer. CTCs can be found in the blood of 20% of patients prior to neoadjuvant therapy. We aimed to assess the suitability of magnetic-activated cell separation (MACS) technology for isolation and cytological characterization of CTCs. In the preclinical part of the study, cell lines were spiked into buffy coat samples derived from healthy donors, and isolated using MACS. Breast cancer cells with preserved cell morphology were successfully isolated. In the clinical part, blood for CTC isolation was drawn from 44 patients with early and locally advanced breast cancer prior to neoadjuvant chemotherapy. Standard Giemsa, Papanicolaou and pancytokeratin staining was applied. 2.3% of samples contained cells that meet both the morphological and immunocytochemical criteria for CTC. In 32.6% of samples, partially degenerated pancytokeratin negative cells with morphological features of tumor cells were observed. In 65.1% of samples, CTCs were not found. In conclusion, our results demonstrate that morphologically intact tumor cells can be isolated using MACS technology. However, morphologically intact tumor cells were not detected in the clinical part of the study. At present, MACS technology does not appear suitable for use in a clinical cytopathology laboratory.