Invasive front in oral squamous cell carcinoma: image and flow cytometric analysis with clinicopathologic correlation

OBJECTIVE: Pathologists have drawn attention to the invasive tumor front (ITF) in the determination of the biologic aggressiveness of oral cancer. We have attempted to discover the prognostic significance of cancer cells with abnormal DNA content at the ITF of oral squamous cell carcinoma. STUDY DESIGN: A comparative DNA analysis by means of image cytometry and flow cytometry was conducted to confirm the usefulness of image cytometry in detecting cancer cells having abnormal DNA content at the ITF. The prognostic value of cancer cells with abnormal DNA content ws examined by a multivariate analysis for 195 patients with oral squamous cell carcinoma. RESULTS: In the comparative DNA analysis, it was suggested that image cytometry is useful for detecting cancer cells with abnormal DNA content (4c exceeding rate 4cER]), which is associated with poor prognosis of patients with oral squamous cell carcinoma. In the multivariate analysis, 3 independent factors were found to significantly influence cause-specific survival. These are, in decreasing order of influence, (1) abnormal DNA content (4cER), (2) clinical stage, and (3) growth type. CONCLUSION: The presence of cancer cells with abnormal DNA content of the ITF in conjunction with clinical findings (clinical stage and growth type) can give additional useful information when selecting treatment strategies for oral cancer patients.