Hepatosplenic T-cell lymphoma (HSTCL) is a rare, highly aggressive peripheral T-cell lymphoma characterized by poor responses to conventional chemotherapy and dismal long-term survival. Allogeneic stem cell transplantation (allo-SCT) has been proposed as the only potentially curative strategy; however, evidence supporting its optimal timing, patient selection, and survival benefit remains limited due to disease rarity and reliance on small case series. This study aimed to evaluate the impact of stem cell transplantation on patient outcomes and to identify determinants of survival using a large, real-world database. A total of 513 patients (105 alloSCT, 38 autoSCT) with pathologically confirmed HSTCL were analyzed from an updated pooled real-world database. Clinical, laboratory, treatment, and outcome variables were systematically extracted. Overall survival (OS) was estimated using the Kaplan–Meier method. Cox proportional hazards model and Log-rank tests were used to assess the influence of demographic and clinicopathologic factors on overall survival (OS). AlloSCT was associated with significantly superior OS compared with autoSCT and chemotherapy (median OS 93 vs. 33 months; HR 0.55, 95% CI 0.31–0.97; p=0.04), and both SCT approaches demonstrated improved survival compared with chemotherapy alone (p<0.0001). In the autoSCT cohort, female sex was associated with improved OS (p=0.047), while CD56 expression predicted inferior OS (p=0.007). Platinum-based first-line regimens were associated with the most favorable outcomes, followed by etoposide-based and other intensive regimens; CHOP/CHOP-like and low-intensity regimens were associated with inferior survival (p=0.01). In the alloSCT cohort, male sex, lymphadenopathy, underlying immunosuppression, and prior splenectomy were associated with worse survival with borderline significance (all p≈0.07). Depth of response at the time of alloSCT significantly influenced outcomes, with complete remission demonstrating superior survival compared with partial response and no response (NR) (p=0.007). Peripheral SC had a better OS than bone marrow (p=0.05). There was no significant difference in OS between total body irradiation (TBI)–based and non-TBI conditioning regimens, although TBI-based regimens demonstrated a plateau in the survival tail. A trend toward improved survival was observed with haploidentical donors compared with matched unrelated and matched sibling donors, though this did not reach statistical significance. Conditioning regimen intensity and number of prior therapy lines did not significantly impact OS. AlloSCT confers a substantial survival advantage in HSTCL. These findings support prioritization of remission induction regimens and early referral for alloSCT as the preferred curative-intent strategy in eligible patients.
Haddad et al. (Sun,) studied this question.