Patients with mantle-cell lymphoma relapsing after autologous stem cell transplantation may be rescued by allogeneic transplantation

Allogeneic Hematopoietic Stem Cell Transplantation in Mantle Cell Lymphoma: A Retrospective Analysis of 7 Patients

Mantle cell lymphoma (MCL) is a B cell non-Hodgkin's lymphoma characterized by a poor prognosis. Many different therapeutic approaches including intensive chemotherapy as well as new targeted therapies are established. However, overall survival remains unsatisfying. As the sole curative option, allogeneic hematopoietic stem cell transplantation (HSCT) has been described, but only a limited number of patients qualify for this procedure. We have retrospectively analyzed 7 patients with stage IV MCL undergoing allogeneic HSCT at our institution. A myeloablative regimen was used in 1 patient, while the other 6 patients received reduced-intensity conditioning. Four patients had an HLA-identical sibling, and the remaining 3 patients had an HLA-identical unrelated donor. One patient developed acute graft-versus-host disease (skin, grade III; intestine, grade II). Two patients died from transplant-related causes, 3 patients died due to progressive disease and the remaining 2 patients are still in complete remission 147 and 8 months after transplantation. Allogeneic HSCT offers a therapeutic treatment option for selected patients in a relapsed/refractory setting. The incorporation of novel agents has improved the outcome of patients with MCL. Thus, the role and optimal time point of allogeneic HSCT should be reevaluated in randomized trials.

Second hematopoietic SCT for lymphoma patients who relapse after autotransplantation: another autograft or switch to allograft?

Although autologous hematopoietic SCT (auto-HSCT) is the only potentially curative treatment for lymphoma that has relapsed after conventional chemotherapy, the prognosis of patients with disease recurrence after auto-HSCT is poor. Some highly selected patients can benefit from second transplants. One-third with late recurrence after initial auto-HSCT may attain a prolonged remission after second auto-HSCT. Non-myeloablative or reduced-intensity conditioning (RIC) allogeneic hematopoietic SCT (allo-HSCT) has been used successfully after auto-HSCT failures, especially in subjects who have an HLA-compatible donor, chemosensitive disease and good performance status. Patients with chemosenstive disease recurrence who have completed at least 1 year after their first auto-HSCT should be considered for a second auto-HSCT. Patients who have chemoresistant disease are best served by participation in a well-designed clinical trial examining novel antitumor agents.

Allogeneic stem cell transplantation for mantle cell lymphoma--does it deserve a better look?

Mantle cell lymphoma is a subtype of non-Hodgkin's lymphoma. Mantle cell is generally considered incurable with a median overall survival of about 3 years. It is most common in 50 - 70 year old individuals and for this reason transplantation is not a common therapeutic option. Autologous stem cell transplantation does not appear to improve survival with most patients relapsing after transplant and no disease-free plateau. We present 6 mantle cell patients that had a mean of 3 different types of therapy prior to allogeneic transplantation. Allogeneic transplantation is associated with substantial mortality post-transplant from acute toxicity and GVHD. Despite the extensive amount of pretransplant therapy in our patient population, there was no transplant related mortality. All patients are alive and in remission a median of 4.3 plus years after transplantation. Survival from the date of diagnosis is a median of 6.5 plus years. The results of this series would suggest that in a selected group of patients allogeneic stem cell transplantation may be the treatment of choice for lymphomas not curable by standard therapy or autotransplant.

Hematopoietic stem cell transplantation in mantle cell lymphoma

BACKGROUND

Patients with mantle cell lymphoma (MCL) have in general, lower response rates and overall survival (OS) than those with other B-cell non-Hodgkin's lymphomas. The role of hematopoietic stem cell transplantation (HSCT) in MCL is unclear. Hence we decided to study the clinical course of patients who received autologous and allogeneic HSCT for MCL.

METHODS

Ninety-seven patients, (80 patients-autologous; 17 patients-allogeneic) who received a HSCT for mantle cell lymphoma were included in the study.

RESULTS

The complete response rates at day 100 between the two groups were similar (73% vs. 62%). Day-100 mortality was higher in the allogeneic HSCT group (19% vs. 0%) (P < 0.01). The estimated 5-year relapse rates, 5-year event-free survival (EFS) and 5-year OS among the allogeneic HSCT patients were 21%, 44% and 49%, respectively, similar to 56%, 39% and 47% in the autologous group. Ten patients received HyperCVAD (hyperfractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone + high-dose methotrexate and cytarabine) +/- rituximab prior to transplant. There have been no relapses or deaths amongst these patients at a median follow-up of 16 months.

CONCLUSIONS

Patients treated with allogeneic HSCT had a lower relapse rate, but similar EFS and OS to autologous HSCT. Treatment of MCL with HyperCVAD +/- rituximab followed by HSCT seems promising.

Current treatment options in aggressive lymphoma

The overall percentage of patients achieving long-term remissions in aggressive non-Hodgkin's lymphoma (NHL) using CHOP or CHOP-based primary chemotherapy is only 40%. Much effort has therefore been concentrated on developing strategies to improve this figure. More intensive variants of CHOP chemotherapy, such as multi-agent "third-generation" regimens, have failed to improve long-term survival, and are also associated with increased toxicity. Hence, there is a need for improved treatment regimens, both as primary therapy and for patients in first and subsequent relapse. This need is most acute in elderly patients (> 60 years of age), who comprise more than 50% of NHL cases and who may not be able to tolerate subsequent intensive chemotherapy at relapse. Approaches currently being examined to improve outcome include: the use of clinical, histological and molecular prognostic factors to establish a patient's risk group, and so define those patients most likely to benefit from early aggressive therapy; the inclusion of high-dose therapy and autologous transplantation; and the integration of novel therapies, such as immunotherapy and radioimmunotherapy, into existing treatment strategies. The impact of these approaches on the treatment of diffuse, large B-cell lymphoma and mantle cell lymphoma is discussed below.

Allogeneic Hematopoietic Stem Cell Transplantation for Lymphoma

For patients with relapsed or refractory Hodgkin's or non-Hodgkin's lymphomas, allogeneic hematopoietic stem cell transplantation (HSCT) is a treatment option when autologous HSCT fails to achieve durable remission or is deemed inappropriate. Allogeneic HSCT can result in long-term survival even in patients with refractory lymphomas. The efficacy of allogeneic HSCT is attributed, at least in part, to an immune-mediated graft-versus-lymphoma (GVL) effect that can also be associated with significant toxicity resulting from graft-versus-host disease. However, clinical evidence of a potent GVL effect is inconsistent. Reduced-intensity conditioning before allogeneic HSCT can facilitate the use of this treatment in older patients and those at high risk. The decrease in toxicity with reduced-intensity regimens may be associated with a loss of antitumor effects. Patients with lymphoma should be selected for allogeneic HSCT on the basis of characteristics that strongly influence transplant outcomes, including histology, chemosensitivity, and donor source.

Limited-stage mantle-cell lymphoma

BACKGROUND

Mantle-cell lymphoma (MCL) is known to have a poor outcome, however, most patients present with advanced-stage disease. Little information is available on limited-stage MCL.

PATIENTS AND METHODS

We retrospectively reviewed clinicopathological information on all patients with limited-stage MCL seen at the British Columbia Cancer Agency since 1984.

RESULTS

Twenty-six patients had low bulk (<10 cm) stage IA (12 patients) or IIA (14 patients) MCL. Initial therapy was involved-field radiation therapy (RT) with or without chemotherapy (CT), 17 patients; CT alone or observation, nine patients. Fifteen patients are alive at a median follow-up of 72 months (range 14-194). Progression-free survival (PFS) at 2 and 5 years was 65% and 46%, and overall survival (OS) 86% and 70%, respectively. Five patients surviving beyond 8 years. Only age and initial use of RT significantly affected PFS. Five-year PFS for patients <60 years of age was 83%, compared with 39% for those aged >/= 60 years, P = 0.04. Patients receiving RT with or without CT (n = 17), had a 5-year PFS of 68%, compared with 11% for those not receiving RT (n = 9, P = 0.002). Receiving RT eliminated the impact of age on PFS (with RT the 5-year PFS was 83% for those aged <60 years and 57% for those >/= 60 years, P = 0.17). Although OS for the whole group was 53% at 6 years, it was 71% for those initially treated with RT, but only 25% for those not given RT (P = 0.13).

CONCLUSION

In our experience, patients with limited-stage MCL had an improved PFS when treated with regimens including RT, with a trend towards improved OS. These results suggest a potentially important role for RT in limited-stage MCL.

Allogeneic peripheral blood stem cell transplantation for high-risk non-Hodgkin's lymphoma

A high incidence of nonrelapse mortality (NRM) has limited the use of allogeneic transplantation for poor prognosis non-Hodgkin's lymphoma (NHL). We sought to improve the outcome of allografting by utilizing Filgrastim-mobilized peripheral blood stem cells (PBSC) in combination with either standard ablative or reduced-intensity conditioning. A total of 21 patients with intermediate/high-grade lymphoma and seven patients with low-grade histology were enrolled on protocols using PBSC. All patients were considered high risk for recurrence and/or NRM because of age >50 (n=16), refractory disease (n=17), failed autologous transplant (n=11) and abnormal organ function (n=2). In all, 17 patients received ablative regimens and 11 received modified conditioning including fludarabine, intravenous busulfan and ATG. Tacrolimus and mini-dose methotrexate were used for graft-versus-host-disease (GVHD) prophylaxis. Median follow-up was 38 months. Disease-free and overall survival were 57 and 58%. Seven of the 11 patients who relapsed after a previous transplant remain disease free. Four of the 10 patients with recurrent/persistent disease post transplant responded to additional therapy including withdrawal of immunosuppression+/-DLI. These results support a potent graft-versus-lymphoma effect and suggest that patients who relapse after an autologous transplant can be salvaged with an allogeneic transplant.

Mantle cell lymphoma: therapeutic strategies are different from CLL

In contrast to the typical course of chronic lymphocytic lymphoma and despite an indolent lymphoma-like presentation, the clinical outcome of mantle cell lymphoma (MCL) is dismal, with a median survival time of 3 years and virtually no long-term survivors. Most patients are diagnosed with advanced stage III/IV disease. Although clinical studies did not prove a clear superiority of anthracyclin-containing combinations, CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone)-like regimens represent the standard therapeutic approach in MCL. Recent randomized studies have shown a benefit of a combined immunochemotherapy strategy (chemotherapy plus rituximab) increasing the complete and overall response rates, whereas further follow-up is pending for evaluation of the progression-free and overall survival. In patients younger than 65 years, a dose-intensive consolidation comprising high-dose radiochemotherapy and subsequent autologous stem cell transplantation after a CHOP-like induction results in an improved progression-free survival. However, despite the benefits of this multimodal approach, most patients relapse even after high-dose therapy. The only curative approach is allogeneic stem cell transplantation, which may be adapted to the elderly MCL patient cohort by modified dose-reduced conditioning regimens. Prospective randomized trials remain critical to further improve the clinical course of MCL with the addition of newer treatment modalities, such as radioactively labeled antibodies and targeted therapies (eg, flavopiridol and PS-341).

Autologous and allogeneic transplantation for aggressive NHL

BACKGROUND

Intermediate- and high-grade NHL are generally chemosensitive diseases with high initial response rates to combination chemotherapy. Dose intensification via autologous and allogeneic transplantation provides viable treatment options in specific clinical settings. Currently, autologous transplantation is the standard of care for relapsed but chemosensitive aggressive B-cell NHL. However, tools such as the International Prognostic Index allow risk-adapted analyses, and show that the magnitude of benefit from autologous transplantation differs in lymphoma subsets.

METHODS

Low-risk patients appear to do well regardless of salvage approaches, whereas high-risk patients have suboptimal outcomes with autologous transplantation. In high-risk patients, high-dose chemotherapy with autologous stem-cell transplantation has been examined as part of initial therapy, with long-term data promising but still evolving.

DISCUSSION

A significant concern with autologous transplantation in aggressive and high-grade NHL is the risk of graft contamination with tumor cells. Several investigators have demonstrated the presence of malignant cells in both BM and PBSC, although the clonagenic potential of such cells is unclear. Allogeneic stem-cell transplantation has several potential advantages over autologous transplantation for NHL,including procurement of an uncontaminated stem-cell graft, GvL effects, and the elimination of hematopoietic stem-cell damage and consequent secondary leukemia.

RESULTS

The ideal application of allogeneic transplantation in aggressive and high-grade lymphomas is still unclear; but the lower relapse rates demonstrated in several comparisons of the two approaches make this an exciting area to pursue. Finally, non-myeloablative stem-cell transplantation may broaden the use of allogeneic transplantation by lowering regimen-related mortality while capitalizing on GvL.

Mantle cell lymphoma: a biological and therapeutic paradigm

Recent classifications of non-Hodgkin's lymphomas (NHL) have strictly individualized mantle cell lymphoma (MCL) on the basis of a combination of morphologic, immunophenotypic, and cytogenetic criteria. This clinicopathological entity now appears to be a biological and therapeutic model for the understanding and treatment of hematologic malignancies. The lymphomogenesis of MCL could be explained by a series of genetic abnormalities which occur at different steps of the disease: (1) mutation and/or loss of the ATM gene in centrocytic cells of the follicle mantle of lymph nodes, leading to the loss of ATM function, particularly involved during the V(D)J recombination process; (2) a t(11;14)(q13;q32) translocation which induces a constitutive Bcl-1/PRAD1/CCND1 expression, responsible for cell cycle activation of centrocytic cells characteristic of typical MCL; and (3) secondary additional chromosomal aberrations, such as a p53 mutation, observed in blastic transformation of MCL. Despite the evaluation of a number of treatment modalities, the optimal management of MCL has not yet been defined: (1) conventional and intensified chemotherapy and monoclonal anti-CD20 antibody therapy appear to be effective for the improvement of response rates and event-free or overall survivals; (2) combinations of different treatment modalities must be tested to modify the natural dismal outcome of the disease; and (3) innovative approaches should be developed. From this point of view, all these considerations offer a fine opportunity for extensive medical reflection.

Stem cell transplantation for mantle cell lymphoma: should it ever be used outside clinical trials?

The outlook for patients with mantle cell lymphoma is poor. The reported median survival in most published series is only 3 to 4 years, and even the most favorable prognostic groups have median survival rates of only 5 years, with no evidence of cure. The use of autologous and allogeneic stem cell transplantation in this disease has increased dramatically in recent years. Despite encouraging reports from single centers and registries, the impact of stem cell transplantation on the outcome for mantle cell lymphoma is unclear. Optimal first-line regimens for mantle cell lymphoma have yet to be defined, and it is therefore difficult to place the role of first remission transplantation in an appropriate context. Prospective randomized trials have been difficult to design and conduct in the absence of a well-defined 'standard' treatment. The role of stem cell transplantation as a salvage strategy is also unknown, although available data suggest that it does not improve survival in heavily pre-treated patients. In the absence of clear evidence for a survival advantage for patients receiving stem cell transplants for mantle cell lymphoma, entry into clinical trials should be a priority.

Biology and management of mantle cell lymphoma

Mantle cell lymphoma is a distinct subtype and accounts for approximately 5 to 10% of non-Hodgkin lymphomas. The malignant cells express pan B-cell markers, including CD19, CD20 and CD22, and the T-cell marker CD5, whereas CD10 and CD23 expression are usually absent. By cytogenetic analysis, the t(11;14)(q13;q32) translocation is commonly observed, resulting in overexpression of cyclin D1. This entity often combines some unfavorable clinical features of the indolent and aggressive lymphoma subtypes, as it is generally incurable and relatively aggressive. It is most commonly observed in men 50 to 70 years of age and is characterized by disseminated disease, usually involving lymph nodes, bone marrow, and spleen. Frequently, there is extranodal involvement including the gastrointestinal tract. These tumors are incurable with the currently available therapeutic options, with usual time to progression after chemotherapy of approximately 1 year. Newer chemotherapy regimens (including stem cell transplantation) and monoclonal antibody-based therapies have shown limited evidence of additional benefit. Overall, the prognosis for patients with mantle cell lymphoma remains poor, and novel strategies are needed.

Allogenic stem cell transplantation as salvage therapy for patients relapsing after autologous transplantation: experience from a single institution

The prognosis of patients relapsing after an autologous transplant (autoSCT) is very poor. Allogenic stem cell transplantation (alloSCT) offers the possibility of curing some of these patients, at the cost, however, of a high transplant related mortality (TRM). The aim of this study was to analyze the outcome of 14 consecutive patients with hematologic malignancies, from a single institution, who underwent alloSCT for progressive disease after autoSCT. Patients had relapsed at a median of 11.5 months (range 2-72) after autoSCT and they underwent alloSCT at a median of 25.5 months (range 7-73) from the first transplant. Ten patients received HLA-identical related peripheral blood progenitor cells, three patients underwent matched-unrelated donor marrow transplants, and one patient received a mismatched related transplant. Conditioning regimens consisted of total body irradiation plus cyclophosphamide (n=5) or melphalan (n=1), or high-dose combination chemotherapy (n=8). Cyclosporin A and methotrexate were administered as graft-versus-host disease (GVHD) prophylaxis. Eight patients (57%) developed grade II-IV acute GVHD. All evaluable patients (n=6) presented extensive chronic GVHD. Overall survival at 1 year was 16% (median 3.5 months, 95% CI 0.7-10.3). Ten patients (71%) died from transplant related complications at a median of 3.5 months (range 0.7-11). Only one patient died of recurrent disease. Three patients remain alive and in complete remission at the time of this report (4, 20 and 20 months, respectively). In conclusion, alloSCT offers the possibility of a sustained control of the disease in some patients who relapse after an autoSCT. However, the procedure is associated with a high transplant-related mortality. Better results might be obtained by carefully selecting patients and by reducing the intensity of the preparative regimen.