PDCD1 and neoplasm: Recently, Tfh-like cells, which display many features of SLO-resident Tfh cells, have been characterized in several tumor entities in humans and their presence correlated with a better prognosis, including breast cancer.4 Similar to bona fide SLO-resident Tfh cells, tumor-associated Tfh-like cells also express very high levels of PD-1, and they produce CXCL13, but they lack expression of CXCR5.