The Significance of DNA Image Analysis in Laryngeal Keratosis

Choi, Jong Ouck; Lee, Jae Yong; Kim, Kyung Hyun; Jung, Kwang Yoon; Choi, Geun

Abstract

Early diagnosis of laryngeal keratosis, a precancerous lesion, is important since it has the possibility to make a malignant change. Since it is believed that laryngeal keratosis progresses to carcinoma in situ or invasive carcinoma through the stage of epithelial proliferation and epithelial dysplasia, if we can predict this progression it will aid in the early diagnosis and treatment of laryngeal cancer. The authors used image analyzer to obtain the DNA index and proliferation index after DNA staining of keratotic epithelial cells to determine the probability of malignant change in laryngeal keratosis. We used specimen obtained from 38 cases of laryngeal keratosis. DNA ploidy was determined by obtaining DNA index with image analyzer(CAS 200, Image analyzer, CAS Ins, USA). And, proliferation index was obtained by ratio of cell content in S phase to G2/M phase of cell cycle. DNA ploidy in mild and moderate dysplasia showed diploidy in all cases, however, in four of nine cases of severe dysplasia showed aneuploidy. Cellular proliferation index in mild dysplasia was 7.5+/-3.12, in moderate dysplasia was 12.3+/-5.71, and in severe dysplasia was 15.8+/-4.21, and statistically significant(p<0.05) high cellular proliferation index was observed in relation to pathological classification. Therefore, DNA analysis using image analyzer can be used to determine the degree of progression of laryngeal keratosis, and it is thought as an objective method for predicting the probability of malignant change and prognosis of the patient.