IMAGE AND FLOW CYTOMETRIC ANALYSES OF DNA CONTENT IN HUMAN SOLID TUMORS - A COMPARATIVE-STUDY

OBJECTIVE: To compare the sensitivity and potentials of flow and image cytometry in assessing DNA content. STUDY DESIGN: The study was perfo rmed on 152 tumors (oral cavity, uterine cervix, bladder, colorectum, breast). Flow cytometry was carried out on cell suspensions from froze n samples, and the results were expressed as the DNA index. Image cyto metry was performed on Feulgen-stained sections, and the results were expressed as the rate of cells exceeding 2.5c or 5c. For colorectal an d breast cancers, DNA content by image cytometry was also measured on imprints and was expressed as the DNA index or rate of cells exceeding 2.5c and 5c. RESULTS: Among flow cytometric diploid tumors, image cyt ometric analysis performed on histologic sections showed about 80% dip loid tumors from the uterine cervix and breast cancers. The frequency decreased to 36% for oral cavity cancers. Generally satisfactory conco rdance was observed when paw cytometric aneuploid tumors were analyzed . A highly significant correlation was observed between DNA indices ob served by flow and image cytometry on imprints. CONCLUSION: Image cyto metry appears more sensitive than flow cytometry in detecting small, a neuploid clones, but its main limitation is the low power in resolving near-diploid cell populations. The results on imprints indicate that image cytometry is a potential alternative approach for small tumor sa mples.