The Expression of CD44v6 Predicts Poor Outcome in Patients with Diffuse Large B Cell Lymphoma Treated with R-CHOP

Background:

CD44 variants have been implicated in metastasis and as an unfavorable prognosis factor in many types of cancers. Our previous study had showed that CD44v6 expression implied a poor clinical outcome in diffuse large B cell lymphoma (DLBCL) patients treated with CHOP. However, it is remains unknown the prognostic value in DLBCL patients treated with R-CHOP due to our sample sizes. Therefore, to examine the prognostic value of CD44v6 expression in DLBCL patients, we performed this retrospective study.

Methods: All 141 patients diagnosed as de novo DLBCL according to WHO classification were further confirmed. All patients treated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone). The expression of CD44v6 was analyzed by immunohistochemistry (IHC). IHC was performed by an automated immunostainer complying with the instructions of the protocols.

Results: Among all the 141 patients, the expression of CD44v6 was observed in 41 cases (29.1%). CD44v6 is expressed predominantly in non-germinal center type DLBCL. There was no significant difference in gender, age, B symptoms, performance status, LDH, stage and IPI score between patients with and without CD44v6 expression. Patients with CD44v6 expression showed significant inferior overall survival, but not event-free survival compared with CD44v6-negative patients. (p=0.022 and p=0.142, respectively).Multivariate analysis showed that the expression of CD44v6, independent of the international prognostic index and cell of origin, implied a poor overall survival (HR=2.223; 95% CI= 1.007-4.906, p=0.048), but not event-free survival (HR=1.457; 95% CI=0.773-2.745, p=0.245).

Conclusions: These data suggest that the expression of CD44v6 implied poor outcome in DLBCL patients treated with R-CHOP.