Flow cytometry and prognostic implications in patients with solid tumors.

Flow cytometric DNA content analysis is a rapid, quantitative method of determining the DNA ploidy status and proliferative index of a given tumor. Abnormal DNA content, or aneuploidy, has been recognized as a marker of malignancy and is present in about 70 per cent of solid tumors. In the majority of solid tumors, the consensus is that the presence of an aneuploid tumor predicts a poorer over-all survival rate and a shorter disease-free interval, indicating that patients with diploid tumors have a more favorable prognosis than those with aneuploid tumors. The prognostic implications of an abnormal DNA content, therefore, suggest either a higher risk of relapse, a worsening of survival rate or a risk for progression of disease in stages I and II carcinoma of the breast, carcinoma of the colon and rectum, superficial carcinoma of the bladder and malignant melanoma. Thus, the assessment of cellular DNA content should be regarded as an additional prognostic determinant and should play an ancillary role in the decisions regarding the management of patients with malignant disease. With the introduction of more sophisticated technology, it will be possible to simultaneously assay for DNA ploidy and cell cycle distribution in addition to a series of tumor markers, such as CEA, and various products of oncogenes, thus providing further understanding of the heterogeneity of solid tumor cells.