Central nervous system relapse in diffuse large B lymphoma: a retrospective cohort study

CNS relapse in patients with LDCGB is a poor prognosis event. The incidence of relapse is variable according to the literature. Data in Latin America is lacking.

In order to establish the incidence of CNS relapse in our cohort, time to CNS relapse and the impact of CNS relapse risk factors, a retrospective cohort study was performed, from January 2012 to June 2017.

One hundred and forty seven patients were analyzed. The median age was 66 years (ICR 56-76); 76 patients (51.70%) were men. The IPI was low or intermediate/low in 115 (78.2%) cases. The CNS IPI was intermediate in 77 (52.4%) and high in 14 (9.5%) of cases. Thirty-five (23.81%) patients received intrathecal prophylaxis. No patient received systemic prophylaxis. During the follow-up, 8 (4.59%) patients had CNS relapse, none of them with high IPI. The median time to relapse was 6.5 months (ICR 5.5-10). Seven (87.5%) patients relapsed within the year of diagnosis. We found no risk factors for CNS involvement in the bivariate analysis. The incidence of relapse was 2.7% (CI 0.2% -4.6%), 4.8% (CI 1.8% -8.9%) and 5.4% (CI 4.5- 8.9%) at 6, 12 and 24 months, respectively.

The incidence of CNS relapse was similar to that described in the international series. Our study confirms that the majority of patients relapse during the first year of follow up. We must carry out broader collaborative work to better establish the risk factor for CNS relapse.