PB2293: REAL WORLD STUDY OF DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL) IN THE ELDERLY: FOURTEEN YEARS OF ONE CENTER’S EXPERIENCE

Topic: 19. Aggressive Non-Hodgkin lymphoma - Clinical Background: DLBCL not otherwise specified (NOS) is the most common subtype of non-Hodgkin lymphoma, and its incidence increases with age. The current standard treatment in all age groups is R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone), nevertheless treatment of elderly DLBCL patients represents a particular challenge due to their comorbidities and performance status. Aims: We report a retrospective analysis of 87 patients, 65 years or older with newly diagnosed DLBCL NOS at our institution between February 2008 and October 2022. Methods: All data was extracted from electronical medical records. The Lugano and Cheson response criteria were used to assess disease response. Statistical analysis was performed using SPSS version 29.0 and survival was estimated by Kaplan-Meier curves and log rank tests. Results: Baseline characteristics are described in Table 1. All patients but one (n=86) were treated and 47 patients (54%) were hospitalized because of infectious complications (n=25, 53%), general condition deterioration (n=6, 13%), heart failure (n=5, 11%), lymphoma progression (LP) (n=4, 9%), impaired renal function (n=3, 6%), tumor lysis syndrome (n=3, 6%) and paralytic ileus (n=2, 4%). Risk factors for hospitalization were ECOG ≥2 (p=0.008, OR 6.0, range 1.60-22.49), elevated LDH (p= 0.04, OR 6.45, range 1.83-22.65) and extranodal disease (p= 0.018, OR 4.3, range 1.2-14.5). Twenty-seven (31%) patients discontinued treatment because of toxicity (n=25, 93%) or LP (n=2, 7%). Overall responses (ORR) in the 57 patients that completed 6 or 8 cycles of treatment were 89%. Fifteen (17%) relapses were recorded. Bulky disease (p=0.04, OR 3.4, range 1.03-11.7) and ECOG ≥2 (p= 0.081, OR 0.23, range 0.04-1.1) were risk factors for relapse in multivariate analysis. With a median follow-up of 24 months (95% CI 1-156), 47 (54%) deaths were reported. Causes of death were therapy-related (n=18, 38%), LP (n=9, 19%), and comorbidities (n=7, 15%); information is not available for the remaining 13 patients. Risk factors for mortality were the presence of 3 or more comorbidities (p=0.042, OR 3.6, range 1.04-12.6), age >80 (p= 0.02, OR 6.5, range 2.02-21.5) and hospitalization (p= 0.004, OR 5.6, range 1.7-18.3). There were no differences in response (p=0.958) or survival (p= 0.561) between patients treated with reduced dose intensity and those treated with full dose. Overall survival (OS) of the cohort was 25 months (range 1-163) and progression free survival (PFS) was 9 months (range 4-103). OS at 50 months was 40% in those patients who completed treatment versus 15% in those who did not (p= 0.009). Summary/Conclusion: -Lower survival rates described in our cohort (OS of 25 moths and PFS of 9 months) are similar to what previously described. -Poor performance status and an explosive disease presentation led to a higher number of hospitalizations (54%) and relapses (17%). -The presence of several comorbidities, advanced age (>80) and the need for hospitalization were associated with a higher risk of death. -Dose intensity adjustment made no difference in terms of survival or depth of response. -OS was enhanced in patients who completed treatment compared to those who didn’t (40% vs 15%) suggesting tailored and reduced dose scheme to be a better treatment strategy in elderly patients. -With the advent of genomic profiling and identification of molecular abnormalities in DLBCL, novel target drugs can increase tolerance and guide more elderly patients toward completion of necessary lines of therapy and improved OS. -Since 2019 comprehensive geriatric assessment (CGA) program has been launched for hematological patients > 70 years of age in our center. Data will be updated during the meeting, focusing on the comparison with the historical series.Keywords: Malignant lymphoma, Lymphoma therapy, Diffuse large B cell lymphoma, Elderly