PDCD1 and angioimmunoblastic T-cell lymphoma: A recent report showed that the combination of PD-1+ tumour cells and the high PD-L1+ group significantly correlated with elevated serum LDH in AITL and PTCL-NOS patients (p = 0.03), and was related to shorter OS in patients with AITL (p = 0.051), being significant in clinical stage IV of AITL (p = 0.007) [20].