Prognostic value of immunophenotype in patients with diffuse large B-cell lymphoma in the immune chemotherapy era

Abstract

Objective To study the prognostic value of immunophenotypes in the patients with diffuse large B-cell lymphoma (DLBCL) and its prognostic significance of immunohistochemical markers for rituximab. Methods The data of 186 initial DLBCL patients were retrospectively analyzed. According to the international prognostic index, all patients were divided into relatively high-risk group and relatively low-risk groups, and the patients in both groups were divided into chemotherapy (CHOP) group and immune chemotherapy (R-CHOP) group, respectively. Immunohistochemical method and Hans typing method were applied to immune classification in all of groups. The prognostic significances of the immunological subtypes in different prognosis group were compared by Log-rank test. Results The 5-year OS rate of the GCB subtype patients in the CHOP group was significantly higher than that of the non-GCB subtype (58.82 % vs 32.00 %, χ2 = 8.482, P= 0.004), while that was no significant difference between GCB and non-GCB subtypes patients in the R-CHOP group (72.97 % vs 61.54 %, χ2 = 2.694, P= 0.101). Further analysis results showed that non-GCB subtype patients treated with R-CHOP had significantly higher 5-year OS rate than those treated with CHOP (61.54 % vs 32.00 %, χ2 = 7.385, P= 0.007). In the 107 cases of low risk group, there was no significant difference in 5-year OS rate between GCB and non-GCB subtype patients in the CHOP group or in the R-CHOP group (all P> 0.05), and there was no significant difference in 5-year OS rates between the CHOP and R-CHOP groups in the GCB group or in the non-GCB group (all P> 0.05). In the 79 cases of high risk group, the 5-year OS rate in the GCB subtype group was significantly higher than that in the non-GCB subtype in the CHOP group (40.00 % vs 22.72 %, χ2 = 3.978, P= 0.045), while there was no significant difference in 5-year OS rates between GCB and non-GCB subtype patients in the R-CHOP group (62.50 % vs 42.31 %, χ2 = 2.072, P= 0.150). Conclusions By immunohistochemistry, DLBCL can be divided into two immunophenotype subgroups, which have guiding significance for early prognosis and therapeutic strategies, but which are no longer or weak in prognostic significance in the era of post-rituximab. R-CHOP improve significantly survival of non-GCB subgroup patients. However, its function needs to be further explored in the GCB subgroup. Key words: Lymphoma, large B-cell, diffuse; Immunophenotyping; Prognosis; Rituximab