The Clinical Significance of DNA Ploidy Analysis in Patients with Rectal Carcinoma and Precancerous Lesion

Objectives: In recent years, DNA ploidy analysis is regarded as having important values in diagnosis and prognostic judgment of malignant tumour. The aim of this study was to explore the clinical significance of DNA ploidy analysis in patients with rectal carcinoma and its precancerous lesions. Subjects and method: Flow cytometry was used to measure the DNA content and ploidy status in normal, precancerous and cancerous fresh rectal tissues. These rectal tissues came from 325 individuals including 120 patients with rectal carcinoma, 25 with proliferative polyps, 155 with villous adenoma and 25 normal controls. The occurrence of DNA heteroploidy was analysed. Results: The positive rate of heteroploidy in patients with rectal carcinoma was significantly higher than that in individuals with proliferative polyps, villous adenoma and normal controls. The positive rate of heteroploidy in patients with villous adenoma with severe atypical proliferation was much higher than that in proliferative polyps, normal controls, and villous adenoma without atypical proliferation, villous adenoma with mild-or-moderated atypical proliferation. The occurrence of DNA heteroploidy was significantly increased with poorer degree of differentiation in rectal carcinoma. Conclusion: The detection of DNA ploidy could be a valuable tool to evaluate the proliferation status and malignant degree of rectal carcinoma. The analysis of DNA ploidy may play an important role in the diagnosis, differential diagnosis, assessment of disease progression and prognosis of rectal carcinoma.