“Vitamin D deficiency (VDD) contributes to worse outcomes in elderly patients with diffuse large B-cell lymphoma (DLBCL) treated with rituximab, according to a study published online Aug. 18 in the Journal of Clinical Oncology.
“Jörg Thomas Bittenbring, MD, from Universitätsklinikum des Saarlandes in Germany, and colleagues examined the impact and mechanisms of VDD in patients with DLBCL. Chemoluminescent immunoassays were used to evaluate 359 pretreatment 25-hydroxyvitamin D3 serum levels from the RICOVER-60 study (6 Versus 8 Cycles of Biweekly CHOP-14 With or Without Rituximab) and 63 from the RICOVER-noRTh study (an amendment to the RICOVER-60 study).
“The researchers found that RICOVER-60 patients treated with rituximab with VDD (≤8 ng/mL) had 3-year event-free survival (EFS) of 59% and 3-year overall survival (OS) of 70%, while those with vitamin D levels >8 ng/mL treated with rituximab had EFS and OS of 79 and 82%, respectively. In multivariate analysis adjusting for International Prognostic Index risk factors, these differences remained significant, with hazard ratios of 2.1 (P = 0.008) for EFS and 1.9 (P = 0.040) for OS. In all 7 individuals with VDD, there were significant increases in rituximab-mediated cellular cytotoxicity (RMCC; P < 0.001) after substitution and normalization of their vitamin D levels.”