The mathematical basis for the increased sensitivity in cancer detection in air-dried cytopreparations.
It is known that the volume of a sphere is 4/3 pi r3, the area of a circle is pi r2, and the nuclear volume remains constant even when a cell is flattened. The effect of air-drying that flattens a spherical nucleus with a radius of r to a discoid nucleus with an expanded radius of R and a thickness of T can be stated as follows: pi R2 = (4/3 pi r3)/T. Based on this formula, a graph was plotted to illustrate the effect of air-drying on the observed nuclear areas (ONA) of cells of various size. The ONA of ethanol-fixed Pap/H&E-stained cells or cells in tissue sections is pi r2; the ONA of air-dried Diff-Quik-stained cells is pi R (2), i.e., (4/3 pi r3)/T. The former follows a first-order straight line, and the latter follows a second-order curve. As a consequence, the subtle "nuclear size enlargement" and "broader nuclear size distribution" of low-grade cancer cells, detectable only by statistical analysis of the data obtained by an image analyzer in ethanol-fixed cytopreparations or in formaldehyde-fixed tissue sections, become augmented to such a degree on the air-dried Diff-Quik-stained preparations that they are easily detected by direct microscopic observation. In conclusion, the increased sensitivity in cancer detection in air-dried cytopreparations is due to the fact that the ONA of air-dried cells reflects nuclear volume.
Yang
G C
GC
Department of Pathology, Cornell University Medical College, New York, New York.
D002467:Cell Nucleus / Q000648:ultrastructure*; D003581:Cytodiagnosis / Q000379:methods*; D003890:Desiccation; D004801:Eosine Yellowish-(YS); D005260:Female; D006416:Hematoxylin; D006801:Humans; D008433:Mathematics; D009369:Neoplasms / Q000175:diagnosis* / Q000473:pathology; D000073718:Pancreatitis-Associated Proteins; D012680:Sensitivity and Specificity; D013048:Specimen Handling; D013194:Staining and Labeling; D014626:Vaginal Smears
D000073718:Pancreatitis-Associated Proteins; C000612141:REG3A protein, human; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin