BIVARIATE RNA AND DNA CONTENT-ANALYSIS IN BREAST-CARCINOMA - BIOLOGICAL SIGNIFICANCE OF RNA-CONTENT

Flow cytometric studies of mammary carcinoma have been limited to DNA content analysis, Simultaneous analysis of DNA and RNA has been applie d to hematological and certain solid neoplasms and has been shown to p rovide valuable information in the clinical assessment of these tumors . To determine whether measuring RNA content during flow cytometric an alysis provides additional information in the clinical assessment of b reast carcinoma, dual-parameter analysis of DNA and RNA content on fre shly disaggregated breast carcinoma specimens was performed, RNA conte nt, divided along the mean (less than or equal to 1.6 and >1.6), corre lated with tumor grade, histological type, hormonal status, and patien t survival, DNA aneuploidy was noted in 247 (69.2%) neoplasms and corr elated significantly with tumor grade and stage but not with clinical outcome. The proliferative fraction, defined as S + G(2)-M and dichoto mized along the mean value (less than or equal to 10% and >10%), corre lated significantly with tumor grade, size, hormonal status, lymph nod e involvement, and survival, Cox's proportional hazard analysis reveal ed that RNA content, proliferative fraction, and tumor stage are indep endent prognostic indicators, Our results indicate that measurement of cellular RNA content provides additional biological information that may be useful in the clinical assessment of breast carcinoma.