DNA measurements for monitoring chemotherapy in advanced head and neck carcinomas

Quantitative DNA measurements have demonstrated prognostic relevance in various malignancies, including head and neck cancer. The application of DNA measurements in monitoring and predicting the outcome of chemotherapy in treating patients with head and neck cancer was investigated.

Twenty-five patients with advanced squamous cell carcinomas of the head and neck who underwent primary chemotherapy with three courses of cisplatin and 5-fluorouracil (5-FU) were examined in this study. Cytologic smears from the tumor site, as well as from normal mucosa, were taken before and 1 week after each course of chemotherapy. Quantitative DNA measurements were performed using an automatic microscope and a TV-based image analysis system. The DNA parameters (ie, mean DNA content of the tumor cells, 2c deviation index (2c DI), 5c exceeding rate (5c ER), DNA malignancy grade, and stemline analysis) were determined from the single cell measurements.

Tumors which responded to chemotherapy showed a shift of the mean DNA content and stemline towards euploidy and a decrease of aneuploid tumor cells with a DNA content of more than 5c. Tumors which did not respond to chemotherapy showed a persistent high percentage of aneuploid tumor cells and a high malignancy grade. These changes in the DNA content were observed after the first course of chemotherapy. In a clinical follow-up, patients with a shift of the DNA data towards euploidy during chemotherapy showed a significant longer recurrence-free interval than patients with residual aneuploid cell clones.

Quantitative DNA measurements appear to be useful in monitoring therapy and to predict the outcome after chemotherapy. Although no typical constellation was found which predicts good or bad response, the DNA data suggest that changes in the data after the first course of chemotherapy may correlate with outcome.