Impact of resource availability on outcomes of Diffuse large B-cell lymphoma. Real World data from Pakistan

1. Patients treated in LMICs have restricted access to detailed immunohistochemistry, FISH testing, PET-CT scan and Rituximab.

2. Patients treated in limited resource settings have inferior OS and DFS as compared to enhanced resources.

The purpose of current study is to assess the impact of resource availability on the outcomes of diffuse large B-cell lymphoma (DLBCL) and identify areas of improvement in managing DLBCL in resource-limited settings. This multi-centric retrospective study included 756 patients across 12 public and private hematology, oncology, and hematopoietic stem cell transplant centers in Pakistan. The median age at diagnosis was 47.92 (14-89) years, higher in resource-enhanced settings than resource-limited ones (p=0.001). The male-to-female ratio was 2:1. Detailed immunohistochemistry (IHC) was available for 4.3% (n=22) patients in resource-limited versus 59.3% (n=155) in enhanced settings (p=0.000). Higher IPI scores, advanced stage, and CNS disease were seen in resource-limited settings (p=0.000). CT scan was the primary diagnostic modality in resource-poor settings compared to PET-scan (64% vs 38.8%, p=0.000). Complete response (CR) rate was lower for resource-limited settings (35.5% vs 54.4%, p=0.000). R-CHOP yielded a higher CR compared to CHOP (p=0.000). In limited resource setting, Rituximab was part of the induction regimen in 43.7% (n=211) of patients, only 10.7% (n=48) completed 6 cycles of rituximab. Only 29% (n=10) of relapsed/refractory patients in limited resources received salvage treatment compared to 48% (n=15) in enhanced settings (p=0.02). For entire cohort OS was 40.6% , higher in enhanced resource setting (53% vs 35.2%, p=0.000). Disease-free survival was 36.3% (47% in enhanced vs 31.4% in limited resource setting, p=0.000). The study highlights disparity in outcomes between patients in resource-limited versus resource-enhanced settings. Efforts are required to bridge this gap by uniform resource allocation and establishing specialized centers.