Survival Rates After Autologous Stem Cell Transplant in THRLBCL
For patients with relapsed/refractory T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) who undergo autologous stem cell transplantation in salvage-sensitive disease, the 2-year progression-free survival is 78% and overall survival is 81%, representing significantly superior outcomes compared to standard diffuse large B-cell lymphoma. 1
Primary Survival Outcomes
The most recent and highest quality evidence specifically addressing THRLBCL comes from a 2024 European Society for Blood and Marrow Transplantation registry study that analyzed 201 patients with THRLBCL undergoing auto-HCT between 2016 and 2021. 1
Key survival metrics for THRLBCL:
- 2-year progression-free survival: 78% 1
- 2-year overall survival: 81% 1
- 2-year relapse incidence: only 16% (significantly lower than DLBCL at 35%) 1
These outcomes remained statistically significant even after propensity score matching and multivariate analysis, with THRLBCL showing a hazard ratio of 0.46 for relapse risk and 0.58 for progression-free survival compared to standard DLBCL. 1
Critical Factors Determining Transplant Success
Disease status at transplantation is the single most important prognostic factor. 1 The 2024 EBMT study specifically included only patients with salvage-sensitive disease as assessed by PET-CT, which explains the excellent outcomes. 1
Patients must meet these criteria for optimal outcomes:
- Chemosensitive disease (responding to salvage therapy) 1
- Complete remission or partial remission status at time of transplant 1
- Good performance status 1
The Italian Society of Hematology guidelines emphasize that patients with chemoresistant disease should not proceed to auto-HCT, as they have predictably poor outcomes. 2
Comparative Context with Other Lymphomas
THRLBCL demonstrates superior outcomes compared to standard DLBCL after auto-HCT:
For broader context with aggressive lymphomas, a 2013 study of high-risk lymphomas showed 5-year overall survival of 75% for patients transplanted in first complete remission versus 59% for those in more advanced stages. 3
Long-Term Survival Considerations
Transplant-related mortality is low in the modern era:
- Non-relapse mortality at 2 years: minimal in the THRLBCL cohort 1
- Historical data from other aggressive lymphomas shows 100-day transplant-related mortality of only 1.4% 4
Late relapses are uncommon but possible:
- Most relapses occur within the first 2-3 years post-transplant 4, 5
- Rare late relapses beyond 5 years have been documented in other aggressive lymphomas 5
- Survival curves typically plateau at 12-24 months, suggesting curative potential 2
Critical Pitfalls to Avoid
Do not proceed with auto-HCT in these scenarios:
- Chemoresistant disease (failure to respond to salvage therapy) 2
- Progressive disease at time of planned transplant 1
- Patients requiring more than one line of salvage therapy to achieve response (these patients have significantly inferior outcomes) 6
Age is not a contraindication: Recent data demonstrates that carefully selected patients aged 70-78 years have similar outcomes to younger patients, supporting auto-HCT feasibility in older fit patients. 6
Alternative Considerations
For patients who fail to achieve chemosensitive disease with salvage therapy, allogeneic stem cell transplantation may be considered, though this carries higher treatment-related mortality (approximately 27.9% at 5 years versus 3.1% for autologous). 3 The NCCN guidelines note that for Richter's transformation (a related aggressive B-cell lymphoma), autologous HCT showed 3-year OS of 59% and relapse-free survival of 45%. 2
The evidence strongly supports auto-HCT as highly effective for salvage-sensitive relapsed/refractory THRLBCL, with outcomes superior to standard DLBCL, but only when disease demonstrates chemosensitivity to salvage therapy. 1