Histopathological assessment of archived formalin-fixed paraffin-embedded sample quality from nasopharyngeal biopsy cases

Abstract

Formalin-fixed paraffin-embedded (FFPE) tissue samples are widely used for diagnostic and research purposes. However, many factors can affect the quality of these samples, potentially compromising subsequent tissue analyses. This study aimed to assess the quality of archived FFPE samples from nasopharyngeal biopsy cases using systematic histopathological evaluation to determine sample suitability for tumour microenvironment (TME) studies. We retrospectively analysed 124 archival FFPE nasopharyngeal biopsy specimens. FFPE tissue sections were stained with routine staining (haematoxylin and eosin) and reviewed by a histopathologist. Histopathological assessment systematically evaluated tissue morphology, tumour presence, stromal component, and lymphoid tissue. From the 124 FFPE samples evaluated, only 97 samples, comprising 55 nasopharyngeal carcinoma and 42 non-tumour samples, fulfilled the inclusion criteria. A systematic histological assessment was crucial for determining the suitability of a sample for cell and tissue structure analysis. This study established a histological quality control framework for assessing archival FFPE samples in the TME study, ensuring reliable and reproducible data for future investigations.