Treatment options for transformed lymphoma: incorporating allogeneic stem cell transplantation in a multimodality approach

Allogeneic hematopoietic stem cell transplantation in patients with advanced indolent lymphoproliferative disorders

BACKGROUND

The role of allogeneic hematopoietic stem cell transplantation for advanced indolent lymphoproliferative disorders remains to be established.

OBJECTIVE

This paper aims to describe the results of allogeneic hematopoietic stem cell transplantation in patients with advanced indolent lymphoproliferative disorders.

METHODS

This article reports on 29 adult patients submitted to allogeneic transplantations from 1997 to 2010.

RESULTS

Most had follicular non-Hodgkin lymphoma (n=14) or chronic lymphocytic leukemia (n=12). The median age was 44 years (range: 24-53 years) and 65% of patients were male. Only 21% had had access to rituximab and 45% to fludarabine. All had advanced disease (stage IV) with partial response or stable disease. Most underwent myeloablative conditioning n=17-59%). In this scenario, refractory disease was observed in seven (24%) patients, the 100-day mortality rate was 17% (n=5) and relapse occurred in four patients (18%). The main cause of death throughout the follow up was refractory disease in six of the 12 patients who died. Moderate and severe chronic graft-versus-host disease was frequent; about 41% of 24 patients analyzed. The overall survival rates and disease free survival at 42 months were 56.7% and 45.4%, respectively. According to Kaplan-Meyer analysis, the median time from diagnosis to transplant predicted the overall survival; however age, gender and conditioning regimen did not predict the prognosis. It was impossible to reach other conclusions because of the small sample size in this study.

CONCLUSIONS

The role of allogeneic transplantations should be re-evaluated in the era of targeted therapy.

Transformed follicular non-Hodgkin lymphoma

Histologic transformation of follicular lymphoma to an aggressive non-Hodgkin lymphoma is a critical biologic event with profound implications on the natural history of this otherwise indolent disease. Recent insights into the genetic and epigenetic basis of transformation have been described, with the recognition of pivotal events governing the initiation and persistence of tumor evolution. Outcomes of patients with transformed lymphoma have historically been poor; however, several studies in the rituximab era suggest that survival may be more favorable than previously recognized. This review highlights our current understanding of transformed follicular lymphoma biology and pathogenesis, current treatment, and future directions.

Outcomes of autologous or allogeneic stem cell transplantation for non-Hodgkin lymphoma

Transplant outcomes of autologous or allogeneic stem cell transplantation (SCT) have not been elucidated as a single cohort in non-Hodgkin lymphoma (NHL). We analyzed the outcomes of 270 adult recipients receiving autologous (auto) SCT (n = 198) or allogeneic (allo) SCT (n = 72) for NHL between the years 2000 and 2010. Five-year overall survival rates for B and T cell NHL were 58% and 50%, respectively (allo-SCT 51% vs. 54% for B and T-cell NHL, and auto-SCT 60% vs. 47% for B and T cell lymphoma, respectively). In multivariate analysis, the number of chemotherapy regimens and disease status pre-SCT were independently associated with long-term outcome after SCT (for both auto- and allo-SCT). We conclude that the type of transplantation offered to patients, based on patient selection and disease-related factors, can achieve long-term survival, highlighting the importance of further improvement in disease control and reducing procedure-related mortality. The role of transplantation needs to be reevaluated in the era of targeted therapy.

Superior long-term outcome of patients with early transformation of non-Hodgkin lymphoma undergoing stem cell transplantation

In this study, we discuss the results of patients with transformed lymphoma (TL) undergoing stem cell transplantation (SCT). Because of the paucity of literature on the treatment of TL, deciding on the optimal evidence-based treatment is a challenge. Herein, our results indicate that patients with early transformation may benefit the most from SCT.

BACKGROUND

Transformed non-Hodgkin's lymphoma arising from follicular lymphoma (TL) carries a poor prognosis with a median survival time after transformation reported to be approximately 1 year.

PATIENTS AND METHODS

Fifty-one consecutive patients with TL received SCT between January 2000 and December 2010 (autologous SCT, n = 44, allogeneic SCT, n = 7).

RESULTS

Thirty-six (70.5%) patients had an early transformation, defined as histologic evidence of transformation at the time of initial diagnosis or transformation within 1 year of follicular lymphoma. Fifteen patients had early stage disease (29%) and 36 (71%) had advanced stage disease on presentation. At the time of analysis, 37 patients were alive with an estimated 5-year overall survival (OS) and event free survival (EFS) of 61.8% and 45%, respectively. OS and EFS were not significantly different between types of transplant procedure. The major cause of transplant failure was disease recurrence, with estimated 2-year relapse rate of 37.4%. Importantly, early transformation was independently associated with improved OS (hazard ratio [HR] 3.29; P = .028) and EFS (HR 2.49; P = .029).

CONCLUSION

Our results indicate that an aggressive transplant approach should be considered first in patients with TL and emphasize the need to incorporate novel strategies (eg, immunomodulation) early post-SCT to prevent relapses as disease recurrence remains the major cause of failure in heavily pretreated patients.

Comparison of outcomes after allogeneic hematopoietic stem cell transplantation in patients with follicular lymphoma, diffuse large B-cell lymphoma associated with follicular lymphoma, or de novo diffuse large B-cell lymphoma

The outcome after allogeneic hematopoietic stem cell transplantation (allo-HCT) for diffuse large B-cell lymphoma (DLBCL) associated with follicular lymphoma (FL), which includes DLBCL with pre- or co-existing FL, remains controversial, and few previous reports have compared the outcomes after allo-HCT for FL, DLBCL associated with FL, and de novo DLBCL. We retrospectively analyzed 97 consecutive patients with FL (n = 46), DLBCL associated with FL (n = 22), or de novo DLBCL (n = 29) who received allo-HCT at our institute between 2000 and 2010. With a median follow-up of 53 months, the 5-year overall survival (OS) and progression-free survival (PFS) were, respectively, 77% and 70% for FL, 62% and 57% for DLBCL associated with FL, and 26% and 23% for de novo DLBCL. The 5-year cumulative incidences of non-relapse mortality and disease progression/relapse were, respectively, 16% and 15% for FL, 19% and 24% for DLBCL associated with FL, and 36% and 41% for de novo DLBCL. By a multivariate analysis, the OS and PFS for DLBCL associated with FL were significantly better than those for de novo DLBCL, whereas they were not significantly different from those for FL. These results suggest that allo-HCT may be a promising option for patients with not only advanced FL but also DLBCL associated with FL.

Long-term outcome after autologous or allogeneic stem cell transplantation in patients with recurrent follicular lymphoma

Thirty-five consecutive patients with follicular lymphoma (FL) receiving SCT at our institution between January 2000 and December 2010 were included in this study. At the time of presentation, 30 (86%) had advanced stage disease and 25 (71%) received three or more chemotherapy regimens prior to transplantation. In all, 12 (34%) patients were in complete response pre-SCT following salvage therapy. At the time of analysis (median follow-up 6 years from diagnosis and 4 years from transplantation), 24 patients were alive with an estimated 5-year OS and PFS of 66.5 and 53%, respectively. OS and PFS in patients receiving auto-SCT (91.7%, 73.3%) were superior compared with patients receiving allo-SCT (53.9%, 43%). Our data support early use of auto-SCT in patients with FL and suggest the need to improve allo-SCT outcome. Integrating novel agents in a combined modality approach may improve long-term outcome in FL.

Immunomodulatory nonablative conditioning regimen for B-cell lymphoid malignancies

Twenty-six patients with recurrent CD20(+) B-cell lymphoid malignancies received fludarabine, cyclophosphamide, and rituximab-based nonablative conditioning followed by either matched related (n = 18) or unrelated (n = 8) donor allogeneic stem cell transplantation (allo-SCT) between March 2008 and May 2011. Median age of patients at transplantation was 59 years (range, 41-64 years). At diagnosis, 20 (77%) had stage IV disease; 23 (88%) received ≥3 regimens, 14 (54%) received ≥4 regimens, and 4 (15%) had earlier autologous-SCT. All patients had either chemosensitive or stable disease and nine (35%) were in complete remission before transplantation. At the time of analysis, 17 patients were alive with an estimated 2-year overall survival and progression-free survival rate of 63% and nonrelapse mortality of 25%. Grade II to IV acute graft-vs-host-disease occurred in 8 (31%) and chronic graft-vs-host-disease in 6 (23%) patients (extensive, n = 3). Causes of death include progressive disease in four, acute graft-vs-host-disease in two (both after receiving donor lymphocyte infusion for mixed chimerism with residual disease), infection in one, and other (e.g., substance abuse, leukoencephalopathy) in two. Six patients required rehospitalization within 100 days of SCT (mean = 10 days; range, 3-18 days). Our data support fludarabine, cyclophosphamide, and rituximab-based nonablative conditioning allo-SCT in CD20(+) B-cell lymphoid malignancies and it is time to compare this regimen with an alternative reduced-intensity conditioning regimen in B-cell malignancies.

Primary central nervous system lymphoma: implication of high-dose chemotherapy followed by auto-SCT

Primary central nervous system lymphoma is a rare and distinct subtype of non-Hodgkin's lymphoma that is sensitive to radiation and chemotherapy. Decisions regarding the initial therapeutic approach are influenced by age and risk of therapy-related neurotoxicity. Despite several albeit small phase II studies, and the acknowledged need for larger prospective trials, there is supporting evidence to consider auto-SCT following induction chemotherapy in patients with good performance status. The international extranodal lymphoma study group is conducting a randomized phase II study comparing consolidative radiation therapy to high-dose therapy. Novel therapeutic options including early aggressive approach with upfront auto-SCT and strategies to prevent relapse following transplantation is an area of focus.