PDCD1 and obesity due to melanocortin 4 receptor deficiency: A study conducted immunohistochemical staining of PD-L1/PD1 in 279 patients who underwent radical prostatectomy indicated that age (≥ 65 years), obesity (BMI ≥ 30), and advanced tumor stage, lymph node metastasis, and high Gleason score patients were related with higher PD-L1 positivity [32].