Plastic-embedded human marrow biopsy specimens: improved histochemical methods.

Improved methods for processing, sectioning, and staining plastic (glycol methacrylate)-embedded human marrow biopsy specimens were studied. Special stains, including naphthol AS-D-chloro-acetate esterase, PAS, reticulin, and iron, have been modified so that they are suitable for undecalcified, 2-microns-thick, plastic-embedded human marrow biopsy specimens. These adaptations permit plastic-embedded marrow specimens to be used for clinical diagnosis. Marrow biopsy specimens embedded in plastic were compared with biopsy specimens preserved by the conventional paraffin method. The plastic-embedded marrows provide better results from morphologic examination (enhancing diagnostic accuracy), permit assessment of bone as well as of marrow, and allow histochemical analysis to be performed.