Correlative microscopy and microprobe analysis in pathology

Abstract

In performing transmission electron microscopic (TEM) studies of biopsies, pathologists must be extremely careful to “aim” the TEM at features of the tumor or pathologic process which are important at the light microscopic (LM) level. Fine structural data devoid of such correlations are generally of no clinical value. For example, a TEM study of a tumor must focus primarily on the tumor cells. Care must be taken not to misidentify stromal cells (e.g., capillaries, fibroblasts) as tumor cells, or else serious errors can occur.Likewise, in performing electron microprobe analysis (EPMA) on biopsies, it is extremely important that the pathologist be able to interpret the spectral findings in light of the H&E section appearance. Like it or not, the current “gold standard” in surgical pathology labs around the world is the H&E stained paraffin section. Accordingly, as in TEM studies, electron microprobe results must be obtained in such a manner that one can relate the findings to the appearance of the biopsy as viewed by light microscopy in an H&E section. If one cannot make that correlation, then one has obtained data that generally will be of little interest to most pathologists and clinicians. Accordingly, our group has stressed the importance of correlative microscopy, and has developed several regimens for analyzing histologic sections. Last year in these proceedings we published a schematic overview of that regimen.