Does the omission of vincristine in patients with diffuse large B cell lymphoma affect treatment outcome?

The standard treatment for diffuse large B cell lymphoma (DLBCL) is rituximab with CHOP (cyclophosphamide, doxorubicin, vincristine (VCR), and prednisone). Maintaining high dose intensity of cytotoxic treatment has been associated with better outcome but little is known about the role of maintaining VCR. This study aimed to answer whether the omission of vincristine due to neurotoxicity affects patient outcome. A Swedish cohort of patients primarily treated with curative intent for DLBCL or high-grade malignant B cell lymphoma was retrospectively analyzed. In total, 541 patients treated between 2000 and 2013 were included. Omission of VCR was decided in 95 (17.6%) patients and was more often decided during the last three cycles (n=86, 90.5%). The omission of VCR did not affect disease-free or overall survival neither in the whole cohort nor in elderly patients. On the contrary, the relative dose intensity of doxorubicin was associated with overall survival (p=0.014). Kidney or adrenal involvement (p=0.014) as well as bulky disease (p=0.037) was found to be associated with worse overall survival. According to our results, clinicians can safely decide to omit VCR in case of severe neurotoxicity due to VCR but should be aware of the importance of giving adequate doses of doxorubicin during treatment given the growing body of evidence on the role of dose intensity on survival. Considering the association of bulky disease and kidney/adrenal manifestation of lymphoma on survival, further studies should focus on whether the treatment options for these subgroups need to be individualized.