Survival and Outcome of Patients with Diffuse Large B-cell Lymphoma According to the Central Nervous System-International Prognostic Index.

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma. Several prognostic scores exist in DLBCL, including the International Prognostic Index (IPI). More recently, a modification of the IPI that estimates the risk of progression to the central nervous system (CNS-IPI) was published. Whether the CNS-IPI index is sufficient to prognosticate DLBCL survival is yet untested.

OBJECTIVES

We aim to describe the outcomes of DLBCL patients based on CNS-IPI risk groups.

METHODS

We retrospectively reviewed all DLBCL cases diagnosed from January 2015 until April 2022 at an academic tertiary hospital in Riyadh, Saudi Arabia. CNS-IPI was calculated at the time of diagnosis. The outcomes were compared between two CNS-IPI risk categories: low and intermediate/high-risk groups. Logrank method was used to calculate P value, and Kaplan-Meier method to estimate survival.

RESULTS

A total of 136 patients were included (median age: 56.5 years), of which 38 (28%) died: 5 in the low-risk group and 33 in the intermediate/high-risk group. Low-risk and intermediate/high-risk CNS-IPI were found in 41 (30%) and 95 (70%) patients, respectively. The median survival in the low-risk and intermediate/high-risk CNS-IPI groups was 66 months [95% CI: 60-not-reached (NR)] and NR (95% CI: 24-NR) (P = 0.007), respectively. Only seven (5%) patients developed progression to the CNS, of which 6 (86%) were in the intermediate/high-risk group.

CONCLUSION

The risk of progression to the central nervous system was moderate in our diffuse large B-cell lymphoma population. Patients with intermediate/high-risk CNS-IPI had worse survival compared with low-risk patients. The CNS-IPI was found to a good model to not only estimate the risk of disease progression to the central nervous system but also overall survival.