Maricer P. Escalón

Autotransplant conditioning regimens for aggressive lymphoma: are we on the right road?

High-dose chemotherapy and autologous stem cell transplant (ASCT) is the standard approach for chemosensitive, relapsed aggressive non-Hodgkins lymphoma (NHL). Various conditioning regimens have been used as treatment before ASCT and disease-free (DFS) and overall survival (OS) rates range from 34 to 60% and 26 to 46%, respectively. To date, few comparative randomized trials have been performed and no regimen has demonstrated superiority to another. Reduction of disease relapse remains the major hurdle for improving patient outcome and in vitro and in vivo purging of lymphoma cells has not necessarily enhanced results. Rituximab pre-mobilization and post-transplant appear to provide better response rates with OS approaching 87–91% at 2–3 years. Newer approaches with radioimmunotherapy may raise DFS to 78% and OS to 93%, albeit with short follow-up. Advances in the conditioning regimens and supportive care have reduced transplant-related mortality to less than 10%. In this review we discuss commonly utilized conditioning regimens, describe their pros and cons and address purging and present conditioning strategies. Owing to the poor outcome with conventional chemotherapy in mantle cell, Burkitts and T-cell lymphoma, we propose the standard approach of front-line ASCT for these high-risk lymphoma patients. Finally, we will present novel strategies, which can enhance the anti-lymphoma effect, at the same time reducing toxicity, to improve the outcome of ASCT in NHL patients.

Cord blood transplantation: evolving strategies to improve engraftment and immune reconstitution

Purpose of review For many patients with relapsed or high-risk hematologic malignancies, allogeneic stem cell transplantation offers the best hope for cure. For patients lacking a suitable family or unrelated donor, umbilical cord blood provides a promising alternative graft source. Dramatic advances in cord blood transplantation (CBT) have been made in the past 2 decades, leading to a rapid expansion of CBT programs worldwide. Recent findings Promising new strategies, including double CBT and ex-vivo graft engineering, have improved myeloid and platelet engraftment rates and kinetics. However, delayed immune reconstitution and associated infectious morbidity and mortality remain a significant challenge, especially in adult CBT recipients. In adults, both impaired recipient thymopoiesis and the lack of transferred memory cells contribute to delayed T cell recovery, resulting in an increased risk of opportunistic infections. Summary Novel clinical approaches in CBT have improved outcomes, especially those associated with delays in myeloid and platelet engraftment. However, delayed immune reconstitution remains a great challenge. Novel strategies, including graft engineering approaches capable of improving T cell recovery, and pharmacologic interventions capable of preserving thymopoiesis and facilitating the recovery of a diverse functional T cell repertoire are being pursued; these approaches have great potential to further improve outcomes after CBT.

[18F]-fluorodeoxyglucose positron emission tomography combined with computed tomography detection of asymptomatic late pulmonary toxicity in patients with non-Hodgkin lymphoma treated with rituximab-containing chemotherapy.

Rituximab is a chimeric anti-CD20 monoclonal antibody widely used in the treatment of B-cell non-Hodgkin lymphomas (NHL). Most adverse effects are due to infusion-related reactions, and severe respiratory complications are rare. We retrospectively reviewed clinical data and serial imaging studies of five patients with NHL treated with rituximab-containing chemotherapy who developed new pulmonary abnormalities on routine follow-up FDG-PET/CT imaging. None of the patients had pulmonary lymphoma or other pulmonary disease before therapy and all remained asymptomatic during follow-up. New pulmonary interstitial FDG-uptake was detected on follow-up FDG-PET/CT between 1 and 3 months post-treatment, preceded computed tomography abnormalities in one case, and persisted for several months. FDG uptake was linear, subpleural with maximum Standardized uptake value (SUV) from 2.0 to 5.84. Rituximab-containing chemotherapy for NHL may be associated with asymptomatic late pulmonary toxicity characterised by a distinct FDG uptake pattern. Awareness of this finding is important and should not be confused with lymphoma.

Autologous transplantation for relapsed non-Hodgkin's lymphoma using intravenous busulfan and cyclophosphamide as conditioning regimen: a single center experience

High-dose chemotherapy with autologous SCT has become standard of care for patients with relapsed aggressive non-Hodgkins lymphoma (NHL). To improve safety and efficacy of this treatment, new conditioning regimens are being developed. We retrospectively reviewed clinical data of patients with relapsed NHL treated at our institution with i.v. BU and CY (BU/CY) as conditioning regimen for autologous SCT between January 2000 and April 2005. We identified 43 patients (24 men, 19 women, median age 50) with diffuse large B-cell lymphoma (n=28), follicular lymphoma (n=8), mantle cell lymphoma (n=4) and peripheral T-cell lymphoma (n=3). Following salvage chemotherapy, there were 26 complete responses, 13 partial responses and 4 stable diseases. Median time to neutrophil and platelet recovery was 11 and 13.5 days, respectively. Treatment-related toxicities included nausea/vomiting, diarrhea and mucositis. The 100-day mortality was 9%: sepsis (n=1), pneumonia (n=1) and hepatic veno-occlusive disease (n=2). Twenty-one patients were followed until death and twenty-one surviving patients were followed for a median of 29 months (range 0.4–76). Three-year estimates of event-free survival, progression-free survival and overall survival were 35, 39 and 43%, respectively. We conclude that i.v. BU/CY is a safe and effective conditioning regimen for autologous SCT in relapsed NHL.

High rate and prolonged duration of complete remissions induced by rituximab, methotrexate, doxorubicin, cyclophosphamide, vincristine, ifosfamide, etoposide, cytarabine, and thalidomide (R-MACLO-IVAM-T), a modification of the National Cancer Institute 89-C-41 regimen, in patients with newly diagnosed mantle cell lymphoma

Novel therapeutic approaches are needed in mantle cell lymphoma (MCL). We conducted a phase II study in MCL testing an intensive regimen, R-MACLO-IVAM-T, a modification of the NCI 89-C-41 protocol. Newly diagnosed patients were treated with rituximab, methotrexate, doxorubicin, cyclophosphamide, and vincristine (cycle 1) followed by rituximab, ifosfamide (and mesna), etoposide, and cytarabine (cycle 2). These two cycles were repeated once, and patients achieving complete response (CR) received maintenance thalidomide. Among the 22 patients enrolled, 21 completed two or more cycles and achieved a CR. Three patients relapsed, while 17 are alive and relapse-free after a median follow-up of 37 months (range 19–65 months). Two patients died: one from sepsis during cycle 1 and another at 38 months while in remission from MCL. The progression-free survival at 3 years was 78% (95% CI: 51–91%). These results compare favorably with previously reported outcomes suggesting that durable remissions can be achieved without myeloablative therapy.

Pharmacotherapy of large B-cell lymphoma

Background: Constituting approximately 30% of lymphoid malignancies, diffuse large B-cell lymphoma (DLBCL) is the most common aggressive lymphoma in adults worldwide. The clinical and biologic heterogeneity that exists in DLBCL suggests that this entity might actually be comprised of several distinct neoplasms that could require different therapeutic approaches. DLBCL was considered incurable until combination chemotherapy became available. Objective: Current treatment strategies for the treatment of untreated and relapsed advanced-stage DLBCL are reviewed; novel treatments for DLBCL are discussed. Methods: Relevant literature was identified using the PubMed search engine and by reviewing abstracts from major conference proceedings. Results/conclusion: Recently, novel therapeutic strategies, including the incorporation of immunotherapy to combination chemotherapy, have improved outcome for patients with DLBCL with cure rates exceeding 50%, especially in younger patients.