Terminal uridine nick end labelling and mitosis in breast carcinoma - Correlation with tumor grade and p53 overexpression

OBJECTIVE: To study the relationship of cell death and proliferation to his tologic grade and p53 expression in invasive carcinoma of the breast. STUDY DESIGN: A total of 31 cases of infiltrating duct carcinoma of the bre ast were randomly selected. The terminal deoxynucleotidyl-transferase-media ted dUTP nick end labelling (TUNEL) reaction and p53 immunostaining were pe rformed on representative paraffin-embedded tissue sections. Mitotic and ap optotic indices (MI and AI) were also measured on hematoxylin-eosin-stained sections. Histologic grade of infiltrating duct carcinoma was performed wi th the help of the Nottingham modification of the Bloom-Richardson system. Tumor grade and p53 overexpression were correlated with MI, AI and AI detec ted by TUNEL. RESULTS: There were a total of 31 infiltrating duct carcinomas of the breas t, of which 13 cases were grade 1 and nine cases each were grade 2 and 3. C ells with positive TUNEL showed a strong brown nuclear positivity. TUNEL sh owed positivity from the periphery of the nuclear margin to the central por tion. AI detected by TUNEL did not correlate with tumor grade (ANOVA, P > . 05). MI was significant only in grade 1 versus grade 3 and 2 versus grade 3 carcinomas (ANOVA, P < .01), The morphologic apoptotic index was significa nt only in grade 1 versus grade 3 carcinomas. Nine cases showed p53 overexp ression, and the vest of the cases were negative for p53 immunostaining. MI , AI and TUNEL were riot significantly different in p53-negative and -posit ive groups. Pearson's correlation coefficient showed that AI and MI were si gnificantly related, but there was no significant relation between AI detec ted by TUNEL and MI. CONCLUSION: MI is still more useful than AI or AI detected by TUNEL in diff erentiating various grades of carcinoma of the breast.