RT Journal Article SR Electronic T1 Prognostic significance of immune checkpoints in the tumour–stromal microenvironment of sebaceous gland carcinoma JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 48 OP 56 DO 10.1136/bjophthalmol-2019-315490 VO 105 IS 1 A1 Lata Singh A1 Mithalesh Kumar Singh A1 Moshahid Alam Rizvi A1 Neelam Pushker A1 Sameer Bakhshi A1 Seema Sen A1 Seema Kashyap YR 2021 UL http://bjo.bmj.com/content/105/1/48.abstract AB Background Immune checkpoint blockade strategies have gained attention in the treatment/prognosis of cancers by targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway alone or in combination with cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) blockade and are currently in clinical trials. The present study investigated the expression of the PD-1, PD-L1, CTLA-4, CD4 and CD8 proteins and their prognostic value in the tumour microenvironment of sebaceous gland carcinoma (SGC).Methods The expression levels of PD-1, PD-L1, CTLA-4, CD4 and CD8 proteins were assessed in 52 cases of SGC by immunohistochemistry and validated by western blotting. mRNA expression was measured by quantitative real-time PCR. Kaplan-Meier curves and Cox proportional hazard models were used to analyse the correlation of protein expression with clinicopathological parameters and disease-free survival.Results The expression of PD-L1 was found to be higher in tumour cells than in stromal cells. In univariate analysis, the expression of PD-1 in tumour-infiltrating lymphocytes (tPD-1) and PD-L1 in tumour cells was associated with reduced disease-free survival, whereas PD-L1 expression in stromal lymphocyte infiltration (sPD-L1) was associated with the increased survival of patients (p<0.05). However, by multivariate analysis, the expression of tPD-1 was found to be an independent prognostic factor for poor survival.Conclusion Our study highlights the prognostic outcome of PD-1 and PD-L1 protein expression in cells of tumour–stromal compartments. These results indicate that the PD-1/PD-L1 pathway mediates important interactions within the tumour microenvironment in SGC.