Background: Independently of the technique for excision used, pterygia recur quite frequent. We investigated whether recurrences can be predicted by means of histological and immunohistological parameters.
Materials and methods: In a prospective clinical investigation the frequency of recurrent pterygia after excision and subsequent autologous limbal grafting was studied. The pterygia of 10 patients without recurrence (mean follow-up time 13 months) were compared retrospectively and semiquantitatively with the pterygia of 7 patients who had a recurrence. The following parameters were taken into consideration: (1) elastoid degeneration; (2) amount of vascularization; (3) morphological signs of "dry eye" (e.g., loss of goblet cells, beginning keratinization); (4) reactive inflammation; (5) amount of CD1a-, CD4-, CD8- and CD68-positive cells; (6) expression of PDGFalpha, PEDGFbeta, EGF, and laminin receptors.
Results: No appreciable differences between recurrent and nonrecurrent pterygia were found.
Conclusion: As adjuvant therapeutic strategies like application of mitomycin C or beta-irradiation may lead to complications, it would be desirable it they could be limited to patients at risk. The histological and immunohistological parameters investigated probably do not allow prediction of pterygial recurrence. Consequently, they are not helpful in deciding whether adjuvant therapy should be started or not.