Statistical analyses revealed that the frequencies of IL-8-positive T cells in patients with “lymphocyte-rich” type B2 thymomas are higher than those in patients with “lymphocyte-poor” type A and B3, confirming that IL-8 positive RTE cells are tightly associated with the potency of intratumorous thymopoiesis (Table 2, Supplementary Fig. 9). Here, CXCL8 is linked to thymoma.