Purpose: The purpose of this study was to evaluate the prognostic significance of cell proliferation markers and DNA ploidy in patients with a squamous cell carcinoma of the head and neck region.
Methods and materials: With flow cytometry, DNA index, G1PF-phase fraction (G1PF), S-phase fraction (SPF), 5-bromo-2'-deoxy-uridine (BrdUrd) labeling-index (LI), and potential doubling time (Tpot), were determined. T-stage and N-stage were assessed in accordance with the TNM classification system (UICC 1987).
Results: After multivariate analysis, it appeared that the probability of locoregional recurrent disease was increased by (a) T4-stage, (b) high values of the ratio SPF to LI, (c) DNA tetraploidy. Prognostic significance G1PF for SPF, LI, and Tpot was not demonstrated. However, the treatment regimen was not uniform for the total group of 103 patients. In 45 patients treated with radiation as single treatment and in 49 patients treated with postoperative radiotherapy, prognostic significance for G1PF, SPF, LI, and Tpot could not be demonstrated either. Separate statistical analysis was not executed for nine patients, treated by surgery alone.
Conclusions: Prognostic significance could not be demonstrated for Tpot, LI, SPF, and G1PF in our series. The ratio of SPF to LI was found to be a promising prognosticator and is regarded to be indicative for the size of the hypoxic fraction. Prognostic significance for DNA ploidy was confirmed.