In an animal study of high-dose-rate brachytherapy comparing doses of 2, 5, 10 and 15 Gy, 10 and 15 Gy appeared to well control a tumor, with 10 Gy slightly better than 15 Gy, and 10 Gy enhanced CD8+ cytotoxic lymphocyte infiltration in the irradiated tumor by 7 folds, while 5 Gy and 15 Gy only enhanced the infiltration by 2 folds.23 The gene discussed is CD8A; the disease is neoplasm.