Revisiting intrathecal thiotepa: Efficacy and safety in secondary CNS malignancies.

Treating metastatic malignancies to the central nervous system (CNS) is challenging because many drugs cannot cross the blood-brain-barrier (BBB). Direct intrathecal (IT) drug administration into the cerebrospinal fluid (CSF) is a strategy to overcome this problem. Thiotepa has effective CNS penetration but its popularity has waned over the last two decades due to concerns about its efficacy and potential systemic toxicity. This review evaluates the available evidence for the use of IT thiotepa in hematologic malignancies and non-CNS solid tumors with leptomeningeal disease metastases (LMD). Our search shows that IT thiotepa is a reasonable alternative in hematologic malignancies and LMD due to solid organ malignancies. This suggests a potential role of IT thiotepa in second-or third-line treatment or a substitute role in cases of drug-shortages and adverse effects with other agents. Future research should focus on rigorous comparative trials to establish its definitive role in the evolving landscape of CNS-directed chemotherapy.

Outcomes from hematopoietic stem cell transplantation following treosulfan-based conditioning: A clinical and pharmacokinetic analysis.

BACKGROUND: The aims of this study are to report our experience with treosulfan-based conditioning regimens for patients with non-malignant hematologic conditions, correlating clinical outcomes at different time points post-transplant with treosulfan exposure (AUC). METHODS: This study was a single-center observational study investigating overall survival (OS), disease-free survival (DFS), and event-free survival (EFS) end-points post-transplant. The consequences of treosulfan AUC with respect to toxicity, correction of underlying disease, and long-term chimerism were also explored using pharmacokinetic analysis. RESULTS: Forty-six patients received 49 transplants with treosulfan and fludarabine-based conditioning between 2005 and 2023. Twenty-four patients also received thiotepa. Donor chimerism was assessed on either whole blood or sorted cell lines at different time points post-transplant. Thirty-nine patients received treosulfan pharmacokinetic assessment to evaluate cumulative AUC, with five infants receiving real-time assessment to facilitate daily dose adjustment. OS, DFS, and EFS were 87%, 81%, and 69%, respectively. Median follow-up was 32.1 months (range 0.82-160 months) following transplant. Lower EFS was associated with patient age (<1 year; p = .057) and lower cumulative treosulfan dose (<42 g/m2; p = .003). Stable donor chimerism in B-cell, NK-cell, and granulocyte lineages at 1-year post-transplant were more prevalent in patients receiving thiotepa conditioning. Two infants required daily dose adjustment to treosulfan to avoid high AUC. CONCLUSIONS: Excellent clinical outcomes and stable chimerism were observed in this patient series. The addition of thiotepa conferred no significant toxicity and trended toward sustained ongoing donor engraftment. Correlating treosulfan AUC with long-term patient outcomes is required.

Thiotepa-busulfan-fludarabine-based conditioning as a promising approach prior to allogeneic hematopoietic stem cell transplantation in patients with blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive myeloid malignancy associated with a poor prognosis. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) has emerged as a potential treatment strategy for BPDCN, standardized conditioning regimens remain lacking. In this manuscript, we present two cases of BPDCN that were treated with a thiotepa-busulfan-fludarabine (TBF)-based conditioning regimen prior to allo-HSCT. Both cases demonstrated complete remission post-transplantation, sustained donor chimerism, and remission maintenance, suggesting the potential efficacy of the TBF conditioning regimen for BPDCN transplantation. Given the small sample size in our study, we emphasize caution and advocate for larger studies to confirm the efficacy of TBF in the treatment of BPDCN.

ABT199/venetoclax synergism with thiotepa enhances the cytotoxicity of fludarabine, cladribine and busulfan in AML cells.

ABT199/venetoclax, an inhibitor of the pro-survival BCL-2 protein, has improved AML treatment. Its efficacy in hematopoietic stem cell transplantation (HSCT), when combined with other chemotherapeutic drugs, has not been thoroughly investigated. The present study demonstrates the synergistic cytotoxicity of ABT199/venetoclax with the DNA alkylator thiotepa (Thio) in AML cells. Cleavage of Caspase 3, PARP1 and HSP90, as well as increased Annexin V positivity, suggest potent activation of apoptosis by this two-drug combination; increased levels of γ-H2AX, P-CHK1 (S317), P-CHK2 (S19) and P-SMC1 (S957) indicate an enhanced DNA damage response. Likewise, the increased level of P-SAPK/JNK (T183/Y185) and decreased P-PI3Kp85 (Y458) suggest enhanced activation of stress signaling pathways. These molecular readouts were synergistically enhanced when ABT199/venetoclax and Thio were combined with fludarabine, cladribine and busulfan. The five-drug combination decreased the levels of BCL-2, BCL-xL and MCL-1, suggesting its potential clinical relevance in overcoming ABT199/venetoclax resistance. Moreover, this combination is active against P53-negative and FLT3-ITD-positive cell lines. Enhanced activation of apoptosis was observed in leukemia patient-derived cell samples exposed to the five-drug combination, suggesting a clinical relevance. The results provide a rationale for clinical trials using these two- and five-drug combinations as part of a conditioning regimen for AML patients undergoing HSCT.

Successful treatment of isolated central nervous system recurrence of primary testicular lymphoma by autologous stem cell transplantation using a conditioning regimen of thiotepa and busulfan.

Primary testicular lymphoma (PTL) frequently relapses in the central nervous system (CNS) despite prophylactic intrathecal chemotherapy, and the outcome for CNS recurrence of PTL is very poor. We report a case of isolated CNS recurrence of bilateral PTL. Our patient achieved complete response (CR) after rituximab-combination chemotherapy for PTL. Approximately five years later, isolated CNS recurrence of PTL occurred. Our patient achieved CR again after high-dose methotrexate therapy and autologous stem cell transplantation (ASCT) with a conditioning regimen of thiotepa and busulfan as a consolidation therapy. The secondary failure of platelet recovery, probably caused by busulfan, occurred after the platelet engraftment. Our patient has remained in CR for over three years. The treatment strategy for CNS recurrence of PTL is mainly whole-brain radiotherapy or high-dose methotrexate-based chemotherapy; however, CNS recurrence of PTL may occur again even after achieving CR. ASCT with a conditioning regimen of thiotepa and busulfan is the optimal consolidation therapy for secondary CNS lymphoma. To the best of our knowledge, this is the second reported case of a patient with isolated CNS recurrence of PTL successfully treated by ASCT with a conditioning regimen of thiotepa and busulfan as a consolidation therapy.

Intrathecal chemotherapy for leptomeningeal disease in high-grade gliomas: a systematic review.

BACKGROUND: Leptomeningeal disease (LMD) secondary to high grade glioma (HGG), such as glioblastoma (GBM), are characterized by the spread of tumor cells to the leptomeninges which further complicates treatment approaches. Intrathecal (IT) chemotherapy has surfaced as a potential strategy to bypass the blood-brain barrier and address the challenges posed by disseminated disease. Here, we present a review of the safety and efficacy of IT chemotherapy in the treatment of LMD secondary to HGG. METHODS: A systematic review following PRISMA guidelines was conducted searching PubMed and Embase from January 1995 to September 2022 using specified terms related to IT chemotherapy for LMD. Included articles involved patients diagnosed with LMD from HGG, treated with intrathecal chemotherapy, and provided survival data. Data, including demographics, tumor characteristics, treatment, and survival information, were collected and independently extracted. RESULTS: A total of 68 patients across 10 clinical studies were diagnosed with LMD from HGG and included in the review. Among these patients, the average age at diagnosis was 44.2 years. GBM was the most common tumor type (n = 58, 85.3%). A majority of the patients presented with recurrent disease (n = 29, 60.4%). The review encompassed various IT chemotherapy regimens, including mafosfamide, thio-TEPA, 5-fluoro-2'-deoxyuridine (FdUrd), methotrexate (MTX), and cytarabine; however, dosages and frequencies were inconsistently reported. The mean progression-free survival (PFS) and overall survival (OS) for this cohort were 7.5 months and 11.7 months, respectively. Common side effects of IT chemotherapy included headaches, nausea, and vomiting, with more severe complications such as myelotoxicity, disseminated intravascular coagulopathy, meningitis, and gastrointestinal toxicity reported in some cases. CONCLUSION: LMD continues to be an uncommon complication associated with HGG with a poor prognosis. This article provides an overview of the presently available literature on IT chemotherapy for LMD secondary to HGG, and their respective treatment protocols with overall survival attributes. Additional research is warranted to ascertain how to maximize the potential efficacy of IT chemotherapy as a treatment option.

Low rate of nonrelapse mortality in under-4-year-olds with ALL given chemotherapeutic conditioning for HSCT: a phase 3 FORUM study.

ABSTRACT: Allogeneic hematopoietic stem cell transplantation (HSCT) is highly effective for treating pediatric high-risk or relapsed acute lymphoblastic leukemia (ALL). For young children, total body irradiation (TBI) is associated with severe late sequelae. In the FORUM study (NCT01949129), we assessed safety, event-free survival (EFS), and overall survival (OS) of 2 TBI-free conditioning regimens in children aged <4 years with ALL. Patients received fludarabine (Flu), thiotepa (Thio), and either busulfan (Bu) or treosulfan (Treo) before HSCT. From 2013 to 2021, 191 children received transplantation and were observed for ≥6 months (median follow-up: 3 years). The 3-year OS was 0.63 (95% confidence interval [95% CI], 0.52-0.72) and 0.76 (95% CI, 0.64-0.84) for Flu/Thio/Bu and Flu/Thio/Treo (P = .075), respectively. Three-year EFS was 0.52 (95% CI, 0.41-0.61) and 0.51 (95% CI, 0.39-0.62), respectively (P = .794). Cumulative incidence of nonrelapse mortality (NRM) and relapse at 3 years were 0.06 (95% CI, 0.02-0.12) vs 0.03 (95% CI: <0.01-0.09) (P = .406) and 0.42 (95% CI, 0.31-0.52) vs 0.45 (95% CI, 0.34-0.56) (P = .920), respectively. Grade >1 acute graft-versus-host disease (GVHD) occurred in 29% of patients receiving Flu/Thio/Bu and 17% of those receiving Flu/Thio/Treo (P = .049), whereas grade 3/4 occurred in 10% and 9%, respectively (P = .813). The 3-year incidence of chronic GVHD was 0.07 (95% CI, 0.03-0.13) vs 0.05 (95% CI, 0.02-0.11), respectively (P = .518). In conclusion, both chemotherapeutic conditioning regimens were well tolerated and NRM was low. However, relapse was the major cause of treatment failure. This trial was registered at www.clinicaltrials.gov as #NCT01949129.

Reduced-Intensity Compared to Nonmyeloablative Conditioning in Patients with Non-Hodgkin Lymphoma Undergoing Allogeneic Hematopoietic Stem Cell Transplantation.

Reduced-intensity conditioning (RIC) and nonmyeloablative (NMA) conditioning are preferred for patients with non-Hodgkin lymphoma (NHL) undergoing allogeneic hematopoietic stem cell transplantation (allo-HCT). Although prior studies have suggested that higher-intensity regimens in RIC-NMA conditioning are associated with inferior outcomes in patients with NHL, the optimal conditioning regimen remains unknown. We performed a retrospective single-center analysis to determine outcomes of adult patients with B cell and T cell NHL who underwent allo-HCT and received either RIC or NMA conditioning between March 2008 and December 2019. RIC regimens included fludarabine-cyclophosphamide-thiotepa-4 Gy-total body irradiation (Flu-Cy-TT-4Gy-TBI), fludarabine-melphalan (Flu-Mel), fludarabine-cyclophosphamide-4 Gy-total body irradiation (Flu-Cy-4Gy-TBI), and fludarabine-busulfan-4 (Flu-Bu-4). The NMA regimen comprised fludarabine-cyclophosphamide-2 Gy-total body irradiation (Flu-Cy-2Gy-TBI). The primary outcome was overall survival (OS); secondary outcomes included progression-free survival (PFS), nonrelapse mortality (NRM), and the incidence of acute and chronic graft-versus-host-disease (GVHD). Of 279 transplants recipients (median age, 58 years), 110 received RIC (55% Flu-Mel, 38% Flu-Cy-TT-4Gy-TBI, 6% Flu-Bu-4, 1% Flu-Cy-4Gy-TBI) and 169 received NMA conditioning with Flu-Cy-2Gy-TBI. With a median of 64 months of follow-up post-allo-HCT, there was no significant difference in OS between the NMA and RIC groups (median, not reached [NR] versus 103 months; P = .1), and this was maintained on multivariable analysis. Similarly, after adjustment for all independently significant covariates (age, Karnofsky Performance Status [KPS], Hematopoietic Cell Transplantation Comorbidity Index [HCT-CI], and disease histology), the regression analysis showed no significant difference in PFS with RIC compared to NMA conditioning (hazard ratio [HR] 1.38; 95% confidence interval [CI], .92 to 2.09; P = .24). On univariable analysis, there was no significant difference in NRM between the RIC and NMA arms (100-day estimate, 10.0% versus 1.8%; P = .5). After adjustment for age, ethnicity, KPS, HCT-CI, GVHD prophylaxis, and donor source, RIC conditioning was associated with a significantly higher incidence of NRM compared to NMA conditioning (HR, 2.61; 95% CI, 1.04 to 6.52; P = .039). On multivariable analysis, compared with the NMA arm, the RIC arm had higher rates of grade II-IV (HR, 2.25; 95% CI, 1.31 to 3.86; P = .002) and grade III-IV acute GVHD (HR, 5.62; 95% CI, 2.03 to 15.6; P < .001). The findings of this study suggest that NMA conditioning with Flu-Cy-TBI-2Gy may be considered over more intensive RIC regimens for patients with NHL undergoing allo-HCT.

Identification of clinical factors impacting outcome in patients undergoing autologous hematopoietic cell transplantation after BEAM and TEAM conditioning.

Organ dysfunction, including pulmonary function impairment, plays a key role in the choice of conditioning chemotherapy before autologous hematopoietic stem cell transplantation (auto-HSCT). Replacement of BCNU/carmustine as part of BEAM (BCNU/carmustine, etoposide, cytarabine, and melphalan) conditioning protocol by thiotepa (TEAM) reduces pulmonary toxicity while maintaining efficacy. We retrospectively analyzed the association of clinical characteristics, comorbidities, and organ function with outcomes after conditioning with BEAM or TEAM. Three hundred ninety-six patients undergoing auto-HSCT (n = 333 with BEAM; n = 63 with TEAM) at our institution between 2008 and 2021 were included in this study. In the multivariate analysis, CO-diffusion capacity corrected for hemoglobin (DLCOcSB) ≤ 60% of predicted, progressive disease (PD) before auto-HSCT, Karnofsky performance score (KPS) ≤ 80%, HCT-CI score ≥ 4, and cardiac disease before auto-HSCT were associated with decreased overall survival (OS) in patients treated with BEAM. In contrast, only PD before auto-HSCT was identified in patients treated with TEAM. Patients conditioned with BEAM and DLCOcSB ≤ 60% had higher non-relapse mortality, including pulmonary cause of death. In summary, we have identified clinical and pulmonary risk factors associated with worse outcomes in patients conditioned with BEAM compared to TEAM. Our data suggest TEAM conditioning as a valid alternative for patients with comorbidities, including pulmonary dysfunction and/or poorer performance scores, before auto-HSCT.

Thiotepa-Based Regimens Are Valid Alternatives to Total Body Irradiation-Based Reduced-Intensity Conditioning Regimens in Patients with Acute Lymphoblastic Leukemia: A Retrospective Study on Behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

Total body irradiation (TBI) at myeloablative doses is superior to chemotherapy-based regimens in young patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, in elderly and unfit patients, in whom reduced-intensity conditioning (RIC) regimens are preferred, whether a TBI-based or a chemotherapy-based approach is better is unexplored. Thiotepa can be used as part of ALL conditioning regimens. The current study aimed to compare transplantation outcomes after RIC with TBI-based or thiotepa-based regimens in patients with ALL. The study cohort comprised patients aged ≥40 years undergoing allo-HSCT for ALL in first complete remission between 2000 and 2020 who received an RIC regimen containing either TBI (4 to 6 Gy) or thiotepa. We identified a total of 265 patients, including 117 who received a TBI-based RIC regimen and 148 who received a thiotepa-based RIC regimen. Univariate analysis revealed no significant differences in the following transplantation outcomes for TBI versus thiotepa: relapse, 23% versus 28% (P = .24); nonrelapse mortality, 20% versus 26% (P = .61); leukemia-free survival, 57% versus 46% (P = .12); overall survival, 67% versus 56% (P = .18); graft-versus-host disease (GVHD]/relapse-free survival, 45% versus 38% (P = .21); grade II-IV acute GVHD, 30% in both groups (P = .84); grade III-IV acute GVHD, 9% versus 10% (P = .89). The sole exception was the incidence of chronic GVHD, which was higher in the recipients of TBI-based regimens (43% versus 29%; P = .03). However, multivariate analysis revealed no differences in transplantation outcomes between the 2 groups. In patients aged ≥40 years receiving RIC, use of a thiotepa-based regimen may represent a valid alternative to TBI-based regimens, as no differences were observed in the main transplantation outcomes.

Incidence, Risk Factors, Characteristics, and Outcome of Chronic Graft Versus Host Disease in Children Undergoing Haploidentical Peripheral Blood Stem Cell Transplant With Post-transplant Cyclophosphamide.

AIM: Chronic graft versus host disease (cGVHD) is a major cause of morbidity postallogeneic peripheral blood stem cell transplant (PBSCT). There is paucity of literature describing incidence, risk factors, characteristics, and outcome of cGVHD in children undergoing haploidentical PBSCT with post-transplant cyclophosphamide (PTCy). Here, we describe our experience from our center regarding the same. METHODS: All children who underwent haploidentical PBSCT with PTCy between January 2016 and December 2021 at our center and survived beyond day+100 post-transplant were included in this retrospective study. Conditioning regimens used were: Thiotepa-Fludarabine-Cyclophosphamide with 2 Gy single fraction total body irradiation, Thiotepa-Busulfan-Fludarabine, Fludarabine-total body irradiation and Fludarabine-Melphalan. Peripheral blood was used as stem cell source in all patients. GVHD prophylaxis was PTCy 50 mg/kg on day +3 and +4, Mycophenolate mofetil and Calcineurin inhibitors. Clinical and laboratory data was electronically retrieved and analyzed based on National Institute of Health Consensus Criteria-2014 at regular intervals. Impact of various patient, donor, and transplant-related factors on development of cGVHD were analyzed. Incidence of relapse, event free survival (EFS) and overall survival (OS) were calculated and compared between cGVHD and no cGVHD groups. Patients with rejection were excluded from risk factor analysis for cGVHD but were considered for survival analysis. RESULTS: Fifty-one children included in this study. Median age of transplant of our cohort was 7.5 years with male:female=1.6:1. Eight patients had rejection with autologous recovery. History of acute GVHD (aGVHD) was present in 15/51 (Grade III to IV in 7/51). cGVHD developed in 19/51 patients (mild-9/51, moderate-6/51, and severe-4/51). Skin was the most common organ involved (100%) followed by gastrointestinal tract (47.4%), liver (36.8%), eyes (21%), lungs (21%), mouth (15.7%), and joints (5.2%). Advanced donor age (>30 y) and previous aGVHD were found to be significantly associated with increased risk of developing cGVHD. At last follow-up, complete response and partial response of cGVHD was seen in 6/19 and 4/19 patients, respectively. Overall mortality was 15/51 (cause of mortality was relapse of cancer 8/15, cGVHD-3/15, other 4/15). EFS and OS of full cohort was 55% and 70.6%, respectively. Compared with patients without cGVHD, patients with cGVHD demonstrated a lower relapse (18.2% vs. 40%, P =0.2333), higher EFS (68.4% vs. 53.1%, P =0.283), and higher OS (73.7% vs. 68.8%, P =0.708). CONCLUSION: Incidence of cGVHD was high in children undergoing haploidentical PBSCT with PTCy. Other than PBSC graft source; donor age and previous aGVHD were the risks factors for development of cGVHD. Patients with cGVHD had lower incidence of relapse translating into better survival but this difference was not statistically significant.

Treosulfan Exposure Predicts Thalassemia-Free Survival in Patients with Beta Thalassemia Major Undergoing Allogeneic Hematopoietic Cell Transplantation.

A toxicity-reduced conditioning regimen with treosulfan, fludarabine, and thiotepa in patients with high-risk ß-thalassemia major has significantly improved hematopoietic stem cell transplantation (HCT) outcomes. However, complications resulting from regimen-related toxicities (RRTs), mixed chimerism, and graft rejection remain a challenge. We evaluated the dose-exposure-response relationship of treosulfan and its active metabolite S, S-EBDM, in a uniform cohort of patients with ß-thalassemia major to identify whether therapeutic drug monitoring (TDM) and dose adjustment of treosulfan is feasible. Plasma treosulfan/S, S-EBDM levels were measured in 77 patients using a validated liquid chromatography with tandem mass spectrometry method, and the pharmacokinetic parameters were estimated using nlmixr2. The influence of treosulfan and S, S-EBDM exposure, and GSTA1/NQO1 polymorphisms on graft rejection, RRTs, chimerism status, and 1-year overall survival (OS), and thalassemia-free survival (TFS) were assessed. We observed that treosulfan exposure was lower in patients with graft rejection than those without (1,655 vs. 2,037 mg•h/L, P = 0.07). Pharmacodynamic modeling analysis to identify therapeutic cutoff revealed that treosulfan exposure ≥1,660 mg•hour/L was significantly associated with better 1-year TFS (97% vs. 81%, P = 0.02) and a trend to better 1-year OS (90% vs. 69%, P = 0.07). Further, multivariate analysis adjusting for known pre-HCT risk factors also revealed treosulfan exposure <1,660 mg•h/L (hazard ratio (HR) = 3.23; 95% confidence interval (CI) = 1.12-9.34; P = 0.03) and GSTA1*B variant genotype (HR = 3.75; 95% CI = 1.04-13.47; P = 0.04) to be independent predictors for inferior 1-year TFS. We conclude that lower treosulfan exposure increases the risk of graft rejection and early transplant-related mortality affecting TFS. As no RRTs were observed with increasing treosulfan exposure, TDM-based dose adjustment could be feasible and beneficial.

Comparison of fludarabine/melphalan (FluMel) with fludarabine/melphalan/BCNU or thiotepa (FBM/FTM) in patients with AML in first complete remission undergoing allogeneic hematopoietic stem cell transplantation - a registry study on behalf of the EBMT Acute Leukemia Working Party.

Conditioning protocols for patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) are being developed continuously to improve their anti-leukemic efficacy and reduce their toxicity. In this study, we compared the conditioning protocol of fludarabine with melphalan 140 mg/m2 (FluMel) with conditioning protocols based on this same backbone but with an additional alkylating agent i.e., either fludarabine/BCNU (also known as carmustine)/melphalan (FBM), or fludarabine/thiotepa/melphalan (FTM) 110 mg/m2. We included 1272 adult patients (FluMel, n = 1002; FBM/FTM, n = 270) with acute myeloid leukemia (AML) with intermediate/poor cytogenetic risk in first complete remission (CR) from the registry of the EBMT Acute Leukemia Working Party. Despite patients in the FBM/FTM group were older (64.1 years vs. 59.8 years, p < 0.001) and had a worse Karnofsky performance score (KPS < 90, 33% vs. 24%, p = 0.003), they showed a better overall survival (OS) (2 y OS: 68.3% vs. 58.1%, p = 0.02) and less non-relapse mortality (NRM) (2 y NRM: 15.8% vs. 22.2%, p = 0.009) compared to patients treated with FluMel. No significant differences were observed in relapse incidence (RI) (2 y RI: 24.9% vs. 23.7%, p = 0.62). In conclusion, the addition of a second alkylating agent (BCNU/carmustine or thiotepa) to FluMel as FBM/FTM conditioning, improves OS in AML patients in first CR with intermediate/poor risk cytogenetics after allo-HCT.

How I treat secondary CNS involvement by aggressive lymphomas.

Secondary central nervous system (CNS) lymphoma (SCNSL) is a rare but clinically challenging scenario with historically disappointing outcomes. SCNSL refers to lymphoma that has spread into the CNS concurrently with systemic disease or CNS relapse during or after frontline immunochemotherapy, presenting with or without systemic lymphoma. Diffuse large B-cell lymphoma (DLBCL) denotes the most common entity, but an increased incidence is observed in other histologies, such as Burkitt lymphoma and mantle-cell lymphoma. The incidence, timing in disease course, location, evidence supporting the use of CNS prophylaxis, and treatment pathways vary according to histology. No randomized data exist to delineate the best treatment approaches with current recommendations based on retrospective and single-arm studies. However, a regimen comprising immunochemotherapy, incorporating agents that cross the blood-brain barrier, followed by thiotepa-containing conditioning and autologous stem-cell transplant outlined in the international MARIETTA study demonstrated improvement in outcomes, representing a major accomplishment in the care of patients with DLBCL with SCNSL. Anti-CD19 chimeric antigen receptor T cell denotes a paradigm shift in the treatment of patients with systemic aggressive lymphomas, with emerging data also demonstrating efficacy without higher neurotoxicity in those with SCNSL. In this manuscript we discuss 5 clinical scenarios and review the evidence supporting our recommendations.

Impact of thiotepa dose-intensity in primary diffuse large B-cell lymphoma of the central nervous system undergoing autologous hematopoietic cell transplant with thiotepa/carmustine conditioning.

Thiotepa/carmustine (TT-BCNU) is a commonly used autologous transplant (ASCT) conditioning regimen for primary DLBCL of the CNS (PCNSL). The total thiotepa dose varies among TT-BCNU recipients, with some centers administering a total dose of 20 mg/kg, while others using 10 mg/kg. We retrospectively assessed the impact of thiotepa dose intensity on ASCT outcomes in 218 adult PCNSL patients who underwent a first ASCT with TT-BCNU conditioning and received either a total thiotepa dose of 10 mg/kg (TT-10 group; N = 90), or 20 mg/kg (TT-20 group; N = 128). The median follow-up of survivors was 22 months. The cumulative incidence of 1-year non-relapse mortality (NRM) for TT-10 and TT-20 cohorts were 6% (95%CI = 2-12%) vs. 4% (95%CI = 1-8%), respectively (p = 0.66). The 3-year cumulative incidence of relapse (15% vs. 13%; p = 0.67), progression-free survival (PFS) (71% vs. 80%; p = 0.25) and overall survival (OS) (79% vs. 83%; p = 0.56) were similar in the TT-10 and TT-20 groups, respectively. On multivariate analysis compared to TT-10, the TT-20 cohort was not associated with significantly different risk of NRM (Hazard ration [HR] = 0.77; p = 0.64), relapse/progression (HR = 0.87; p = 0.74), PFS (HR = 0.80; p = 0.48) or OS (HR = 1.10; p = 0.80). In conclusion thiotepa dose-intensity in TT-BCNU conditioning does not impact ASCT outcomes of PCNSL patients.

Impact of Thiotepa-Based Autologous Hematopoietic Cell Transplantation in Primary Central Nervous System Lymphoma in First Complete Remission: A University of California Hematologic Malignancies Consortium Retrospective Analysis.

BACKGROUND: The choice between nonmyeloablative chemotherapy (NMA-C) or autologous hematopoietic cell transplantation (autoHCT) as consolidation in primary central nervous system lymphoma (PCNSL), and timing of autoHCT differs among centers. We aimed to clarify these points. METHODS: We retrospectively analyzed PCNSL adult patients who received consolidation in CR1 or underwent autoHCT during their treatment course. Cohort A included those who underwent autoHCT in CR1, cohort B included those who underwent NMA-C in CR1, and cohort C included patients who underwent autoHCT in CR2+. We compared cohorts A and B, and cohorts A and C. The primary endpoint was overall survival (OS), and secondary endpoints were progression-free survival (PFS), treatment-related mortality (TRM) and cumulative incidence of relapse (CIR). RESULTS: 36 patients were included in cohort A, 30 in cohort B, and 14 in cohort C. The 5-year OS for cohorts A vs B and vs C were 90.7% vs 62.8% (P = .045) and vs 77.9% (P = .32), respectively. The 5-year PFS from diagnosis for cohorts A vs B was 87.8% vs 37.3% (P < .001). The 5-year PFS from autoHCT for cohorts A vs C was 87.6% vs 58.4% (P = .023). The 5-year TRM and CIR in cohorts A vs B was 9.4% vs 9.5% (P = .674), and 2.9% vs 53.2% (P < .001), respectively. The 5-year TRM and CIR in cohorts A vs C from the time of autoHCT was 9.5% vs 22.1% (P = .188), and 2.9% vs 19.5% (P = .104), respectively. CONCLUSION: Despite the limitations, thiotepa-based autoHCT in CR1 appears to improve outcomes in eligible patients with PCNSL.

Long-Term Results with Thiotepa-Containing Conditioning Regimens for Autologous Stem Cell Transplantation.

Autologous stem cell transplantation (ASCT) remains a cornerstone in the treatment of both Hodgkin lymphoma (HL) and various non-Hodgkin lymphoma (NHL) subtypes. BEAM (carmustine, etoposide, cytarabine, and melphalan) is the most frequently used conditioning regimen; however, owing due to limited availability and toxicity of carmustine, thiotepa-containing regimens have been suggested. We previously reported encouraging results in ASCT with a TECAM (thiotepa, etoposide, cyclophosphamide, cytarabine, and melphalan) conditioning regimen from 2000 to 2013. We aimed to update our experience with the TECAM regimen by adding our experience from 2013 to 2020 to the previously reported cohort. Moreover, we aimed to use the detailed data for the 2 transplant cohorts to identify improvements in ASCT outcomes in the recent era. We retrospectively analyzed all lymphoma patients who underwent ASCT at our center between January 2000 and December 2020. A total of 353 lymphoma patients were included (142 in the newer cohort added to 211 previously reported patients), all of whom were treated with our standard TECAM conditioning regimen. The cohort included 127 patients with HL, 107 with DLBCL, and 119 with other NHL subtypes. The newer cohort was characterized by significantly poorer Eastern Cooperative Oncology Group Performance Status (ECOG-PS) prior to ASCT (45.7% versus 19.3% with ECOG-PS ≥1; P < .01), whereas a higher proportion of patients entered transplantation in complete response (CR) (71.9% versus 47.8%; P < .01). The median follow-up after ASCT was 136.4 months (95% confidence interval [CI], 91.4 to 181.4 months). The 3-year progression-free survival (PFS) and overall survival (OS) rates post-ASCT for the entire cohort were 59.8% and 79.3%, respectively. Evaluating the 303 of 353 patients (86.4%) who entered ASCT with a responsive disease-a population that represents today's approach to the selection of patients for ASCT-the 3-year PFS and OS rates were 61.5% and 81.9%, respectively. In this population, the 3-year PFS rate was 62.2% for HL, 62.6% for DLBCL, 64.3% for primary central nervous system lymphoma (PCNSL), and the 3-year OS rate were 90.1%, 75.2%, and 78.6%, respectively. OS was significantly better in the newer cohort (P < .01), but not when evaluating only patients who entered ASCT with responsive disease. Dose reductions, poor disease status, and poor ECOG-PS at ASCT entry were associated with worse outcomes across all lymphoma subtypes. In accordance with our previous report, patients entering transplantation for DLBCL with a partial response achieved similar outcomes as those with a CR. Eighteen patients died within the first 100 days, 8 due to disease progression and 10 due to transplantation-related complications (2.8%). There were no cases of interstitial pneumonitis syndrome. Twenty-two cases (6.2%) of secondary malignancies were documented. Our results confirm that TECAM is an effective and safe conditioning regimen for ASCT in patients with HL and various NHLs, including favorable results in PCNSL. Despite a higher proportion of frail patients, the newer cohort's outcomes were favorable, driven by better lymphoma control pretransplantation. In the DLBCL cohort, ECOG-PS had more prognostic value than achieving a CR pre-ASCT, a finding relevant to the optimal allocation of patients to different treatment options in the era of chimeric antigen receptor T cell availability.

Tiotepa en pacientes con Leucemia Linfoblástica aguda con infiltración meningo encefálica en remisión completa y con indicación de trasplante alogénico / Thiotepa in patients with acute lymphoblastic leukemia with meningobrain infiltration in complete remission and with indication for allogeneic transplant

INTRODUCCIÓN: Cuadro clínico: La leucemia linfoblástica aguda (LLA) es un tipo de cáncer que afecta las células formadoras de linfocitos en la médula ósea, y se presenta en adultos y niños. En Perú, la LLA es uno de los 10 tipos de cáncer más comunes, predominando en hombres. Además, la LLA es el cáncer más común en niños menores de 15 años, representando aproximadamente el 25% de los casos de cáncer en este grupo de edad. En el Registro de Cáncer de Lima Metropolitana, se observa que más de un tercio de todas las neoplasias malignas en niños son leucemias, con una incidencia mayor en el periodo 2013-2015 que en el periodo 2010-2012. Es importante destacar que la LLA progresa rápidamente y requiere tratamiento imediato. Tecnología sanitária: La tiotepa es un agente alquilante polifuncional, se utiliza en combinación con otros medicamentos quimioterápicos, ya sea con o sin radiación corporal total (RCT), para tratar a pacientes adultos y pediátricos con enfermedades hematoló