Predicting Recurrence and Survival in Patients with Laryngeal Cancer by Means of DNA Cytometry, Tumor Front Grading, and Proliferation Markers

Abstract

The cure rates for squamous cell carcinoma of the larynx have improved little over the past few decades. Despite the large number of therapeutic and histopathologic studies that have been performed, there are currently no morphologic or cytologic markers available to predict outcome in patients with laryngeal cancer. In an attempt to create such a system, tissues from 40 patients who underwent surgery for carcinoma of the larynx were examined for this pilot study. The examinations included routine histology, morphologic grading at the tumor front, immunohistochemical identification of the proliferation markers proliferating cell nuclear antigen (PCNA) and Ki67, and quantitative DNA analysis. By means of the stepwise multivariate Cox regression analysis with forward selection, factors that were highly correlated to the development of recurrent disease and survival were determined. We found that the results of the DNA analysis (ie, 2c deviation index, DNA malignancy grade), along with the morphologic tumor front grading and Ki67 score, were closely related to prognosis (p < .01). All of these factors reflect tumor biology. No correlation was found for the Broders grading or for any other clinical parameter. With the test battery used in this preliminary study, patients at high risk for developing tumor recurrences could be recognized. The advantages of this technique are that it is an objective assessment of the tumor and that it can be performed on preoperative biopsy specimens. This might influence decisions regarding therapeutic management and could eventually lead to more appropriate and individualized therapy.