Clinical characteristics and survival outcomes of a large cohort of patients diagnosed with diffuse large B-cell lymphoma: Data from the GOTEL Lymphoma Registry.

e19070 Background: Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma. It is a heterogeneous and aggressive disease, whose survival has improved significantly since the introduction of immunochemotherapy, achieving cure rates of up to 60–70%. Currently, there is limited real-world evidence in the literature regarding lymphoid neoplasms, and more specifically DLBCL, due to the scarcity of population-based registries. The aim of this study was to describe demographic and clinical characteristics as well as survival outcomes of patients diagnosed with DLBCL treated at Spanish centers. Methods: A retrospective, multicenter study was conducted including patients with DLBCL diagnosed at oncology departments of GOTEL-affiliated centers and registered in the national lymphoid neoplasm registry between 2000 and 2023. Epidemiological and clinical data were collected and analyzed descriptively. Survival probabilities were estimated using the Kaplan–Meier method with 95% confidence intervals. Results: A total of 504 patients were analyzed. Demographic and clinical characteristics are summarized in Table 1. After a median follow-up of 6.5 years, 45.4% of patients were alive and disease-free, 7.7% had active disease, and 41.3% had died. Most patients (94.6%) received first-line immunochemotherapy, with 23.8% developing refractory or relapsed disease. Median relapse-free survival was not reached, and median overall survival (OS) was 10.2 years (95% CI, 8.30–12.46). The 1-, 5-, and 10-year OS rates were 82.9%, 63.3%, and 51.1%, respectively. The leading cause of death was primary disease (54.3%), followed by infectious diseases (13.1%) and secondary malignancies (8.2%). Conclusions: Our study describes the main clinical characteristics and survival outcomes of a large cohort of Spanish patients with DLBCL treated across multiple centers, representing one of the population-based registries with the longest follow-up reported to date. Such studies are essential to characterize real-world populations and to develop specific treatment protocols, as well as follow-up strategies for long-term survivors. Patients with DLBCL (n = 504) Sex Male: 54.0% Female: 46.0% Median age 65 years (17-98) Stage I:16.9% II: 24.8%III: 18.7%IV: 35.5%Unknown: 4.1% ECOG 0: 31.2% 1: 41.1%2: 15.3%3: 6.5%4: 1.2% Unknown: 4.8% IPI 0-1: 29.0% 2-3: 39.7% 4-5: 18.5%Unknown: 12.9% Primary extranodal: 180 (35.7%) Spleen: 1.4%Gastric: 6.5%Liver: 1.4%Intestinal: 3.6%Head and neck: 4.8%Bone: 5.2%Lung: 3.2%Testicular: 2.0%Unknown: 1.0%Others: 5.2% Bulky mass 38.1% LDH increased 51.2% Causes of death (n = 208) Primary tumor: 54.3%Second malignancy: 8.2%Other: Neurological: 5.0% Cardiovascular: 5.0% Infectious: 13.1% Respiratory: 1.5% Myelodysplastic syndrome: 0.5% Unknown: 12.0%