In one study including patients with mature B cell lymphoma treated with chemotherapy, patients with thymic hyperplasia showed a faster recovery of sjTREC levels and CD31+ recent thymic emigrants (RTE) counts than patients with comparable age, gender, diagnosis, disease stage, thymic volume and output function at baseline but without thymic hyperplasia; furthermore, they had a faster repopulation of both naïve CD4+ T cell and natural regulatory CD4+ T cell subsets than those without thymic hyperplasia (8). Here, PECAM1 is linked to B-cell non-Hodgkin lymphoma.