Prognostic value of telomerase and DNA ploidy in laryngeal carcinoma

ABSTRACT

Prognosis of carcinoma of the larynx is currently based on the morphologic analysis of the tumor extent, differentiation -grading and type of microscopic invasion. The DNA ploidy status and the cell proliferation activity may give complementary information about the prognosis. Telomerase may be used as a measure of tumor proliferation. The aim of this work is to investigate the probable application of telomerase as measure of cell immortalization as well as DNA ploidy as a measure of cell proliferation in prognosis of patients with laryngeal carcinoma. The work was carried out as a prospective observational study that included 35 patients with laryngeal carcinoma who were treated surgically at Ain Shams University Hospitals, Cairo, Egypt. Flowcytometric analysis and biochemical assay of telomerase, using human Telomerase Reverse Transcriptase [hTERT] mRNA assay by RT-PCR, in resected specimens were done. The proliferative indices in different parts of the tumor were found to be significantly different from each other, with those of tumor edges being the highest. The ploidy status at the edge of the tumor was significantly different between surviving and non-surviving patients, while the tumor core proliferative index was found to be significantly lower in patients without recurrence than those with recurrence. Agradient of telomerase levels was noticed. with levels from tumor cores being highest followed by tumor edges, resection margins and least levels in lymph nodes. Multivariate analysis showed hTERT levels in tumor edges to significantly affect survival. Both Flowcytometric parameters and telomerase activity may be useful as a prognostic factor for survival in patients with laryngeal carcinoma. Telomerase activity may be used for biologic demarcation for conservational laryngeal surgery, as well as a 'spectral' marker