Retrospective DNA analysis of head and neck squamous cell carcinoma.

Abnormal cellular DNA content, a hallmark of malignancy, is known to occur in squamous cell carcinoma of the head and neck. The significance of this finding has yet to be elucidated. Paraffin-embedded blocks from 46 squamous cell carcinomas of the head and neck were sectioned, dewaxed, and made into a suspension of bare nuclei by mechanical mincing and enzymatic digestion. The nuclei were stained with propidium iodide, and quantitative DNA measurements were obtained with flow cytometry. The results were compared with existing prognostic factors: DNA aneuploidy was identified in 41% of the specimens and was significantly correlated with tumor size and surgical stage; the relationship between DNA aneuploidy and anatomic site approaches statistical significance. There was no correlation with histologic grade or presence or absence of cervical metastasis.