Potential prognostic value of PD-L1 and NKG2A expression in Indonesian patients with skin nodular melanoma.

ObjectiveBiomarker mRNA levels have been suggested to be predictors of patient survival and therapy response in melanoma cases. This study aimed to investigate the correlations between the mRNA expression levels of PD-L1 and NKG2A in melanoma tissue with clinicopathologic characteristics and survival in Indonesian primary nodular melanoma patients.ResultsThirty-one tissue samples were obtained; two were excluded from survival analysis due to Breslow depth of less than 4 mm. The median survival of upregulated and normoregulated PD-L1-patients were 15.800 ± 2.345 and 28.945 ± 4.126 months, respectively. However, this difference was not significant statistically (p = 0.086). Upregulated and normoregulated NKG2A patients differed very little in median survival time (25.943 ± 7.415 vs 26.470 ± 3.854 months; p = 0.981). Expression of PD-L1 and NKG2A were strongly correlated (rs: 0.787, p < 0.001). No clinicopathologic associations with PD-L1 and NKG2A mRNA levels were observed. These results suggest that PD-L1 may have potential as a prognostic factor. Although an unlikely prognostic factor, NKG2A may become an adjunct target for therapy. The strong correlation between PD-L1 and NKG2A suggests that anti-PD-1 and anti-NKG2A agents could be effective in patients with PD-L1 upregulation. The mRNA levels of these two genes may help direct choice of immunotherapy and predict patient outcomes.