The present invention relates to the use of 4-(4-Fluoro-2-methoxyphenyl)-N-{3-[(S-methylsulfonimidoyl)methyl]phenyl}-1,3,5-triazin-2-amine (compound A), more particularly (+)-4-(4-Fluoro-2-methoxyphenyl)-N-{3-[(S-methylsulfonimidoyl)methyl]phenyl}-1,3,5-triazin-2-amine (compound A), for treating lymphoma, preferably diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma, follicular lymphoma, diffuse large B-cell Burkitt’s lymphoma, adult T-cell lymphoma (ATL) and Hodgkin’s lymphoma, more preferably DLBCL and ATL.本發明係關於4-(4-氟-2-甲氧苯基)-N-{3-[(S-甲基磺醯亞胺醯基)甲基]苯基}-1,3,5-三-2-胺(化合物A)、更具體而言(+)-4-(4-氟-2-甲氧苯基)-N-{3-[(S-甲基磺醯亞胺醯基)甲基]苯基}-1,3,5-三-2-胺(化合物A)之用途,其用於治療淋巴癌、較佳地彌漫性大B細胞淋巴癌(DLBCL)、被套細胞淋巴癌、濾泡性淋巴癌、彌漫性大B細胞柏基特氏淋巴癌(diffuse large B-cell Burkitt’s lymphoma)、成人T細胞淋巴癌(ATL)及何傑金氏淋巴癌(Hodgkin’s lymphoma)、更佳地DLBCL及ATL。