Evaluation of pd-1, pd-l1, and cytotoxic T-lymphocyteassociated protein 4 expressions together with clinicopathological findings in clear cell, papillary, and chromophobe types of renal cell carcinoma

Our study aimed to determine the expressions of programmed death protein 1 (PD-1), programmed death ligand protein 1 (PD-L1), and cytotoxic T-lymphocyte- associated protein 4 (CTLA-4) to investigate and compare the differences between early and advanced cases in the 3 most common types of renal cell carcinoma (RCC) and reveal their correlations with prognosis and survival. A total of 166 RCC cases diagnosed between 2010 and 2019 in our hospital were included. PD-1, PD-L1, and CTLA-4 markers were applied to the paraffin blocks of the cases using an immunohistochemical method, and their expression status was evaluated by distinguishing subtypes in advanced- and early-stage RCCs. It was observed that PD-L1 positivity in the tumour cells, in clear cell RCC, was statistically significantly more frequent in advanced-stage cases compared to early-stage cases. It was concluded that cases with PD-L1 positivity in tumour- infiltrating mononuclear cells (TIMC) in clear cell and chromophobe RCC had a shorter survival. The frequency of perinephritic fat invasion and necrosis was higher in cases with PD-L1 expression in TIMC. We think that PD-1, PD-L1, and CTLA-4 must be considered together in advanced stage RCC for the treatment of both pathway inhibitors. Further large studies will shed light on the immunotherapy options at the advanced stage of all RCC types even in the absence of metastasis.

Status of PD-1 and PD-L1 expression in invasive urothelial carcinoma of the bladder with mismatch repair protein deficiency

It has been reported that mismatch repair deficient (d-MMR) tumors show sensitivity to immune checkpoint inhibitors. We aimed to evaluate the correlation of d-MMR and PD-1/PD-L1 expression in invasive urothelial carcinoma of the bladder. Tissue microarray (TMA) tissues were stained PD-1/PD-L1 and MMR proteins. The expression ratio of these markers has been compared with histopathologic parameters. d-MMR tumors were more superficial muscle invasive (p = 0.012). When the d-MMR, and PD-1/PD-L1 expression ratios were examined, a significant correlation was obtained between the d-MMR and PD-L1 expression ratio of > 5% in both the tumor and immune cells (p = 0.02 and p = 0.004, respectively). The expression ratio was higher in the patients without MMR loss. PD-1 and PD-L1expression in those with MSH6 loss was one or none. When PD1/PDL1 expression was compared with histopathological parameters, a significant relationship was observed between tumor grade and depth of muscle invasion. PD-L1 expression was not observed in the superficial muscle invasive tumors. This study was shown the status of d-MMR and PD-1/PD-L1 in invasive urothelial cancers and their correlation with prognostic markers. PD-1/PD-L1 expression may contribute to the progression and poor prognosis of bladder cancer. However, further studies are required to research the clinical utility.