Discerning the Primary Carcinoma in Malignant Peritoneal and Pleural Effusions Using Imaging Mass Spectrometry—A Feasibility Study

Abstract

Purpose Malignant effusions challenge diagnostic accuracy due to cytomorphologic overlaps between various malignant primaries. Workup of this material to establish a correct diagnosis is time consuming and limited by the sparsity of material. In order to circumvent these drawbacks, the use of MALDI imaging MS (IMS) as a diagnostic platform has been explored. Experimental design Cytology cell blocks from malignant effusions (serous ovarian carcinoma and several non‐ovarian carcinomas including gastric adenocarcinoma) containing at least 30% neoplastic cells are selected for generation of cytology microarrays (CMA). CMA sections are transferred to conductive glass slides, subjected to on‐tissue tryptic digestion, and matrix application for MALDI–IMS analysis. Results Supervised classification analysis identifies serous ovarian carcinomas as the source of malignant effusions with a sensitivity of 85.7% when compared to samples from all other included primary sites. When compared to gastric adenocarcinoma, serous ovarian carcinoma samples can be delineated with a sensitivity of 97.3%. Conclusion and clinical relevance These preliminary results highlight that MALDI–IMS allows subtyping of malignant effusions to identify the precise origin of neoplastic cells. While achieving similar results compared to classical approaches such as immunocytology, more material is conserved that will be available for further tests.

Histopathologic, immunophenotypic, and proteomics characteristics of low-grade phyllodes tumor and fibroadenoma: more similarities than differences

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Mass Spectrometry Imaging for Reliable and Fast Classification of Non-Small Cell Lung Cancer Subtypes

“…The classification of MSI data has been mainly performed using LDA and SVM [14][15][16][17][18][19][20]. An RF classification algorithm has previously been applied to classify MSI data but not on a large clinically relevant sample cohort [21,22].…”

Next-generation protein analysis in the pathology department

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