Pretherapeutic flow cytometric dna investigations in radiotherapy patients with maxillo-facial carcinomas

Abstract

In order to analyze the possible meaning of cellular DNA content and cell cycle phases for the radiosensitivity and the prognosis of human malignant tumors, flow cytometric measurements have been performed in biopsies of 131 patients with histologically proven squamous cell carcinomas of the maxillo-facial region. In two-thirds of the patients ( 88 131 ; 67%), aneuploid tumor cell lines have been found, only 33% ( 43 131 ) had a diploid DNA distribution pattern. The average DNA index (DI) of the aneuploid carcinomas was 3.4 ± 0.6 (normal nonmalignant tissue DI = 2.0). The frequency of S-phase cells, which represents the ‘proliferative activity’, was between 4.8 and 63.2%, regardless of the ploidy stages. The aneuploid carcinomas had about twice as many S-phase cells (mean 23.7 ± 11.8%) than diploid tumors (mean 12.7 ± 4.8%). Mean survival for patients with diploid carcinoma and aneuploid carcinoma was 12 and 9.5 months, respectively. Concerning the relationship of S-phase frequency and survival times in our material there was a high negative statistical correlation (Spearman-Rank test) in patients with diploid carcinomas. A high S-phase fraction resulted in short survival times. No correlation was found in the aneuploid carcinomas: patients with tumors in high S-phase values in their biopsies showed no difference in prognosis in comparison to tumors with lower S-phase fractions.