[An improved paraffin embedding method for small core needle biopsy: technical introduction and evaluation].

PURPOSE: Modified agar pre-embedded paraffin embedding method was proposed to evaluate the effects on tissue integrity, histological morphology, protein and DNA detection in small specimens of core needle biopsies.

METHODS

The core needle biopsy specimens of 10 patients with oral mucosal squamous cell carcinoma were subjected to modified agar pre-embedded paraffin embedding using molded embedding molds and conventional paraffin embedding respectively, the dehydration time of the former was 3.5 h and that of the latter was 12 h. After tissue treatment, H-E staining, histological morphology, immunohistochemistry (IHC), and DNA fluorescence in situ hybridization (FISH) were performed, respectively. The results were compared and analyzed using GraphPad Prism 9 software package.

RESULTS

The modified agar pre-embedding method was less difficult to perform than the agar pre-embedding method, and easier to be promoted. Compared with conventional paraffin embedding method, the tissue dehydration time was significantly reduced(P＜0.001), and the results of microscopic histological morphology and subsequent IHC and FISH assays were reliable.

CONCLUSIONS

The modified agar pre-embedded paraffin embedding method meets the requirements of clinical pathological diagnosis for tissue processing, and is worthy of clinical application for core needle biopsy specimens.