OBJECTIVETo investigate the value of PET/CT after chemotherapy for evaluating therapeutic efficacy of patients with diffuse large B-cell lymphoma (DLBCL).

METHODS(18)F-FDG PET/CT was performed before and after 6-8 cycles of chemotherapy in 73 newly diagnosed patients with DLBCL from September 2005 to January 2012. The results of pre-treatment PET/CT was compared with results of post-treatment PET/CT. These patients were divided into 3 groups: complete response group, partial response group and no response group. The post-treatment PET/CT results was used to assess its ability to predict progression-free survival (PFS) and overall survival (OS).

RESULTSThe comparison of PET/CT results before and after chemotherapy showed that 2-year PFS rates of complete response group, partial response group and no response group were 82% (41/50), 45.5% (5/11) and 8.3% (1/12), respectively; and the 3-year OS rates of 3 groups were 88% (44/50), 54.5% (6/11) and 8.3% (1/12) respectively (both P < 0.01). The 2-year PFS rate and the 3-year OS rate of the complete response group and partial response group were significantly higher than those of no response group (both P < 0.05), and there was also significant statistical difference between partial response group and complete response group in 2-year PFS rate and 3-year OS rate (both P < 0.05).

CONCLUSIONThe post-treatment PET/CT can be accurately used to evaluate the curative efficacy of chemotherapy and prognosis of patients with DLBCL.