Proliferative activity and p53 expression in primary and recurrent pterygia

Purpose: To assess p53 expression and proliferative activity in primary and recurrent pterygia from the same eyes. Design: Retrospective comparative human tissue study. Participants: Tissue from excised primary pterygia that did not recur (group A, n = 10) was compared with tissue from primary pterygia that recurred (group B, n = 10) and to the recurrent pterygia tissue that was excised from subjects in group B (group C, n = 10), Ten normal conjunctivas served as controls (group D). Methods: Sections from each pterygium were immunostained with the MIB-1 and bp53. 12 monoclonal antibodies that react with Ki-67 and p53 antigens, respectively. Main Outcome Measures: Proliferative activity was calculated as the mean of the MIB-1 positive cell count per eyepiece grid in high magnification (x40) (positive cell count/grid). Percentage of positive cells of all cells in the grid area was evaluated in the p53-stained sections. Results: Proliferative activity was found in the epithelium overlying the pterygia and normal conjunctiva. The mean MIB-1 positive cell count/grid +/- standard error was 2.84 +/- 1.07, 1.74 +/- 0.82, 3.83 +/- 1.35, and 0.86 +/- 0.33 in groups A, B, C, and D, respectively (P = 0.17, Kruskal-Wallis). P53 staining was found in 50% of pterygia in groups A, B, and C; none of the normal conjunctival tissues showed p53 immunoreactivity. Four of five p53-positive tissues in group B were p53-negative in group C. In the p53-positive pterygia, less than 10% of cells were p53 positive. However, p53-positive pterygia had higher mean MIB-1 positive cell count/grid +/- standard error as compared with the p53-negative lesions, 4.56 +/- 0.94 vs 1.39 +/- 0.59 (P = 0.021, Mann-Whitney). Conclusions: p53 immunoreactivity and high proliferative activity in the epithelium overlying the pterygium are not associated with recurrence of pterygium. Ophthalmology 2001,108:985-988 (C) 2001 by the American Academy of Ophthalmology.