Correlation between apoptotic figure counting and the TUNEL technique.
OBJECTIVE: To compare histologic detection of apoptotic (AP) figures and terminal transferase UTP nick end labeling (TUNEL) detection in colorectal carcinomas and lymphomas. STUDY DESIGN: We evaluated the percentage of AP cells by AP figure counting and by the TUNEL technique in formalin-paraffin material from 39 tumors--29 colorectal carcinomas and 10 non-Hodgkin's lymphomas. The Lucia G image analysis system (Laboratory Imaging, Prague, Czech Republic) was used for cellularity evaluation and AP counting. RESULTS: On average, 0.81 +/- 0.5% AP cells were detected by figure counting; 0.91 +/- 0.35% were identified by TUNEL. A statistically high correlation between these techniques was found using Pearson's correlation coefficient (r = .56, P < .001). TUNEL, although probably more sensitive, was difficult to standardize. CONCLUSION: AP figure counting seems to be the method of choice for routine work, particularly because of its cost effectiveness and reproducibility.