P156 | INTRA- VS EXTRA-REGIONAL REFERRAL OF HEMATOLOGICAL PATIENTS DO NOT AFFECT CAR-T CELL THERAPY OUTCOME: A SINGLE-CENTER 5-YEAR EXPERIENCE

Chimeric Antigen Receptor (CAR)-T cell therapy is the best treatment option for most of relapsed/refractory hematological malignancies, including DLBCL, PMBCL, MCL, B-ALL, and MM. In Italy, patients are often referred from distant regions to specialized Hub centers. Timely patient referral has been associated with better outcomes, and delayed access to CAR-T may negatively impact the eligibility of patients and the final efficacy of the treatment. We aim to comparatively investigate characteristics and outcomes of patients treated with CAR-T call for any indication at our Center based on referral origin (intra- vs extra-regional). We retrospectively analyzed 143 patients treated with CAR-T cell therapy at Humanitas Research Hospital in Lombardy between 2020 and 2024 for hematological maligancies. Patient characteristics and clinical outcomes were compared between intra- and extra-regional referrals. Figure 1 illustrates the evolving geographic distribution of referred patients over time. The number of patients treated annually increased from 19 in 2020 to 48 in 2024. Meanwhile, the proportion of extra-regional referrals decreased from 57.9% to 37.5%. This trend likely reflects the rapid expansion of CAR-T centers in Italy, growing from 10 to 44 institutions over the same time. Table 1 shows the characteristics of patients across the groups. Only age significantly differed between intra- and extra-regional groups (median 64 vs 60 years, p=0.009); we observed no significant differences for sex, disease subtype, ECOG performance status, or CAR-Haematotox score. Interestingly, no significant difference was observed in terms of time from diagnosis to infusion (18 months), and number of previous therapy lines (median 2) between the groups. At day 90, complete remission (CR) rate was comparable between intra- and extra-regional patients (56.2% vs 56.5%, p=1.00). Similarly, as shown in figure 2, PFS is not significantly different between the groups (1-year-PFS 50% vs 61%, p=0.341). In conclusion, in our 5-year single-center experience, the referral origin (intra- vs extra-regional) of hematologic patients did not significantly impact CAR-T cell therapy outcomes.