Biomarkers expression among paired serous ovarian cancer primary lesions and their peritoneal cavity metastases in treatment‐naïve patients: A single‐center study. (25th February 2022)

• Record Type: Journal Article
• Authors: Nikas, Ilias P.; Lee, Cheol; Song, Min Ji; Kim, Bohyun; Ryu, Han Suk
• Is Part Of: Cancer medicine. Volume 11:Number 11(2022)
• Page Start: 2193
• Page End: 2203
• Publication Date: 2022-02-25
• Subjects: ascitic fluid -- cytopathological techniques -- extracellular matrix metalloproteinase inducer (EMMPRIN) -- immune checkpoint inhibitors -- immunohistochemistry -- neoplasm metastasis -- prognosis; 616.994005
• DOI: 10.1002/cam4.4600
• Languages: English
• ISSNs: 2045-7634

Abstract

Abstract: Background: High‐grade serous ovarian carcinoma (HGSOC), the most common histologic subtype of ovarian epithelial cancer, is associated with treatment resistance, enhanced recurrence rates, and poor prognosis. HGSOCs often metastasize to the peritoneal cavity, while fluid cytology examination could identify such metastases. This retrospective study aimed to identify potential biomarker discrepancies between paired HGSOC primary tissues and metastatic peritoneal fluid cytology samples, processed as cell blocks (CBs). Methods: Twenty‐four pairs of formalin‐fixed, paraffin‐embedded primary tissues and metastatic CBs from an equal number of treatment‐naïve patients were used, and immunohistochemistry (IHC) for epidermal growth factor receptor (EGFR), human epidermal growth factor receptor, programmed cell death‐1 ligand 1 (PD‐L1), and CD147 was applied. Results: 13/24 pairs showed discordant EGFR IHC results; in all these 13 patients, EGFR was positive (≥1+ membranous staining intensity found in at least 10% of the cancer cells) in the peritoneal, yet negative in the primary tissue samples. Notably, EGFR IHC was positive in 15/24 of the metastatic, whereas in just 2/24 of the primary HGSOC samples (p < 0.001). Although most PD‐L1 results were concordant, 5/24 and 6/24 pairs exhibited discordant results when stained with the E1L3N and 22C3 clones, respectively. Lastly, CD147 overexpression was found more often in the metastatic rather than the matched primary HGSOCs stained with CD147, though the difference was not significant. Conclusions: Cytology from effusions could be considered for biomarker testing when present, even when tissue from the primary cancer is also available and adequately cellular, as it could provide additional information of potential clinical significance. Abstract : This study aimed to identify potential biomarker discrepancies between primary tissues with high‐grade serous ovarian cancer (HGSOC) and their paired peritoneal fluid metastases, processed as cell blocks. EGFR, HER2, PD‐L1, and CD147 immunohistochemical expression was compared between 24 HGSOC pairs. EGFR overexpression was found more commonly in the metastatic than the primary samples, at a significant level ( p < 0.001). Cytology from effusions could be considered for biomarker testing when present, even when tissue from the primary cancer is also available and adequately cellular, as it could provide additional information of potential clinical significance.