Abstract
The study aimed to evaluate whether there is a difference in the expression of programmed cell death 1 ligand (PD-L1) in the cell lining of endometrioma between cases with and without recurrent disease. Additionally, we sought to assess the effect of cyst size and serum CA125 level on the expression of PD-L1 staining. The pathological specimens were immunohistochemically stained for PD-L1 in women who underwent surgery for endometrioma. All patients were evaluated to confirm if their endometriomas had recurred or not. A total of 36 patients who underwent surgery for endometrioma were included. The study population was divided into two groups according to their recurrence status. The study group (having recurrence) (n=12) and the control group (having no recurrence) (n=24) were compared regarding their demographic and clinical characteristics and PD-L1 staining. PD-L1 staining and the intensity of PD-L1 staining did not differ between the patients with and without recurrence. No variable, including parity, cyst size, serum CA125 level, and PD-L1 staining, was found to be significant in determining recurrence. No significant difference was found between the groups with and without PD-L1 staining in terms of cyst size and serum CA125 level. Although we have shown that PD-L1 expression could not be used for the prediction of recurrence, further studies are needed to assess this issue and to guide the development of new immunotherapeutic agents on this basis.