NEW YORK (Reuters Health) – In the rituximab era, it’s not necessary to administer prophylaxis against central nervous system (CNS) disease in patients with diffuse large B-cell lymphoma (DLBCL), according to “real world” data from a large national database.
The data confirm a low rate of CNS recurrence and show no survival benefit with prophylaxis, Dr. Gregory Abel from Dana Farber Cancer Institute in Boston and a multicenter team report in the journal Cancer, available online now.
CNS disease in patients with DLBCL has a high mortality rate, prompting some clinicians to opt for the administration of prophylaxis against CNS disease in these patients.
However, practice patterns and outcomes associated with CNS prophylaxis have not been well characterized since the adoption of rituximab as a standard component of DLBCL therapy.
To investigate, Dr. Abel and colleagues took advantage of the National Comprehensive Cancer Network Non-Hodgkin Lymphoma Outcomes Database, which collects clinical and outcomes data for patients at seven participating centers.
They identified 989 patients with newly diagnosed DLBCL between January 2001 and July 2008, who had no evidence of baseline CNS disease and had received R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) within 180 days of diagnosis.
A total of 117 patients (12%) received CNS prophylaxis (methotrexate and/or cytarabine); 72% received intrathecal therapy and 28% received systemic therapy.
Rates of prophylaxis were “modest” even among patients who had several high-risk features, “perhaps reflecting the continued national controversy regarding its use,” the authors note.
Involvement of bone marrow, other high-risk site, more than one extranodal site, higher international Prognostic Index score, and higher stage were each associated with receiving CNS prophylaxis (all P < 0.0001).
At a median follow-up of 2.5 years, there were 20 CNS recurrences (2%) and three-quarters of these patients died within a median of one year. Overall survival was not affected by prophylaxis, the investigators report.
“Given the overall low rate of CNS recurrence and lack of prophylaxis-associated survival benefit, the current data called into question the practice of CNS prophylaxis in the rituximab era,” they conclude.
“With such low rates of CNS relapse (even among patients classically considered at high risk) and no evidence of a survival benefit, the numbers needed to treat to prevent death from CNS relapse would be quite high based on our findings,” they point out.
“For clinicians who choose not to offer CNS prophylaxis for patients in the rituximab treatment era, our data are reassuring. Indeed, unless better markers of elevated CNS relapse risk can be identified, it may be time to seriously re-evaluate or even completely abandon this practice,” they conclude.
Cancer 2011.
