New Biomarkers Predict Early Recurrent Pterygium

eye test
close up of the advance pterygium during eye examination.
Clinicians may be able to use tear cytokine concentrations to determine clinical strategies.

The presence of inflammatory tear cytokines may be instrumental in predicting pterygium recurrence, according to a study published in Experimental Eye Research.  

Researchers collected preoperative tear samples from 89 patients with primary pterygium (median age 45 years, 64 women, 75 non-recurrent, 10 recurrent, mean duration 7 years) who received pterygium resection at a single center between 2015 and 2017. They performed slit lamp evaluation, tear break-up time (TBUT) analysis, corneal fluorescein staining, Schirmer I test, and administered the Ocular Surface Disease Index (OSDI) to all participants. The team compared tear cytokine levels and constructed machine learning models to differentiate between  recurrent and non-recurrent primary pterygium.

Investigators noted that IL-8, MMP-9, MMP-1, bFGF, and VEGF levels were higher among patients with recurrent pterygium compared with patients with non-recurrent pterygium. They determined that 76.4% of patients with pterygium had dry eye (OSDI score 29.94±16.26) and noted an 11.23% recurrence rate during the 2-year follow-up. Patients with recurrent pterygium had a longer duration, higher-grade pterygium, and a higher prevalence of dry eye. Despite higher cytokine concentrations of IL-8, MMP-9, MMP-1, bFGF, and VEGF in tear samples, researchers noted no significant differences in expression levels between the recurrent and non-recurrent groups in pterygium tissue samples.  

Investigators used these values to construct a prognostic model and determined that 44 patients were at high risk for pterygium recurrence. The team determined that higher concentrations of FGF-2, IL-8, MMP-1, MMP-9, and VEGF were associated with shorter recurrent-free survival (RFS) time than lower cytokine concentrations.  

“Based on the nomogram estimation, we can personally treat pterygium patients and offer better clinical strategies,” according to the researchers. “For example, when treating patients with high nomogram scores, more radical and aggressive adjuvant therapy, such as preoperative dry eye treatment, intraoperative use of 5-fluorouracil, mitomycin C and bevacizumab and intensively postoperative anti-inflammatory therapy as well as closely follow-up are needed. Patients with low nomogram scores would not need the same treatment strategy.”

Study limitations include a small sample size, short study duration, and single center design.


Wan Q, Wan P, Liu W, et al. Tear film cytokines as prognostic indicators for predicting early recurrent pterygium. Exp Eye Res. Published online June 6, 2022. doi:10.1016/j.exer.2022.109140.