Allogeneic Hematopoietic Stem Cell Transplantation for Lymphoma

VRP immunotherapy targeting neu: treatment efficacy and evidence for immunoediting in a stringent rat mammary tumor model

The ability to overcome intrinsic tolerance to a strict "self" tumor-associated antigen (TAA) and successfully treat pre-existing tumor is the most stringent test for anti-tumor immunotherapeutic strategies. Although this capacity has been demonstrated in various models using complicated strategies that may not be readily translated into the clinical arena, straightforward antigen-specific immunotherapeutic strategies in the most stringent models of common epithelial cancers have largely failed to meet this standard. We employed an immunotherapeutic strategy using an alphavirus-based, virus-like replicon particle (VRP), which has in vivo tropism for dendritic cells, to elicit immune responses to the non-mutated TAA rat neu in an aggressive rat mammary tumor model. Using this VRP-based immunotherapeutic strategy targeting a single TAA, we generated effective anti-tumor immunity in the setting of pre-existing tumor resulting in the cure of 36% of rats over multiple experiments, P = 0.002. We also observed down-regulation of rat neu expression in tumors that showed initial responses followed by tumor escape with resumption of rapid tumor growth. These responses were accompanied by significant anti-tumor proliferative responses and CD8+ cellular tumor infiltrates, all of which were restricted to animals receiving the anti-neu immunotherapy. Together these data, obtained in a stringent "self" TAA model, indicate that the VRP-based antigen-specific immunotherapy elicits sufficiently potent immune responses to exert immunologic pressure, selection, and editing of the growing tumors, thus supporting the activity of this straightforward immunotherapy and suggesting that it is a promising platform upon which to build even more potent strategies.

Prognostic impact of pretransplantation computed tomography and gallium scans in patients with Hodgkin lymphoma with poor prognosis undergoing hematopoietic stem cell transplantation

BACKGROUND

The present study evaluated computed tomography (CT) and Gallium-67 scanning (67Ga) before transplantation as prognostic factors for overall survival (OS) and event-free survival (EFS) in patients with relapsed or primary refractory Hodgkin lymphoma undergoing high-dose chemotherapy and stem cell transplantation.

PATIENTS AND METHODS

Forty-five patients were included. Of these, 10 (22%) had positive CT and 67Ga scan results, 21 (47%) had negative results of both techniques, 12 (27%) had positive CT/negative 67Ga scan results, and 2 (5%) had negative CT/positive 67Ga scan results.

RESULTS

Patients with positive CT/67Ga scan results had a significantly worse EFS and OS at 5 years than those with negative 67Ga scan results, whether it was associated with positive or negative CT scan results (0 and 25% vs. 83% and 90% vs. 74% and 83%, respectively; P < 0.001). With a median follow-up of 59 months (range, 6-150 months), no differences were observed between patients with negative CT/67Ga scan results and those with positive CT/negative 67Ga scan results, with an EFS and OS at 5 years of 74% vs. 83% and 83% vs. 90%, respectively. In multivariate analysis, the presence of pretransplantation positive CT/67Ga scan results adversely influenced EFS and OS (hazard ratio, 39; 95% confidence interval, 8-202 [P < 0.001] and hazard ratio, 24; 95% confidence interval, 4-135 [P < 0.001], respectively).

CONCLUSION

Gallium-67 scans help to identify pretransplantation CT-positive patients with a different outcome. A group of patients with positive CT/negative 67Ga scan results before transplantation who showed a favorable outcome with a low rate of relapse and another group of patients with positive CT/67Ga scan results before transplantation who showed poor prognosis did not benefit from autologous stem cell transplantation. They should be offered other therapeutic strategies.

German Hodgkin's Lymphoma Study Group Trials: Lessons from the Past and Current Strategies

Over the past decades, Hodgkin's lymphoma has become one of the most curable tumors in adults. This is mainly because of large clinical trials using risk-adapted, highly effective therapy modalities. For a long time, radiation therapy was the standard for treating patients with Hodgkin's lymphoma. Within the past 20 years, management has undergone a paradigm shift from the use of chemotherapy as an adjunct to radiation therapy in advanced-stage disease to combined therapy modalities with chemotherapy and involved-field irradiation in early stages and time- and dose-intensified effective drug regimens in advanced stages. Modern therapeutic strategies aim at reducing therapy-associated acute and late toxicities, while maintaining the highest tumor control. Founded in 1978, the German Hodgkin's Lymphoma Study Group has initiated numerous clinical trials contributing to the high cure rate in all stages of this lymphoma entity. This article gives an overview of the German Hodgkin's Lymphoma Study Group trials and a review of the current treatment strategies.

Mantle cell lymphoma

PURPOSE OF REVIEW

Mantle cell lymphoma is the B-cell lymphoma with the worst prognosis. Until now, no standard treatment has resulted in cure. Improvements in understanding of the disease are needed to advance therapeutic efforts.

RECENT FINDINGS

Pathology and immunohistochemistry can identify the subset of patients with the worse prognosis. New data suggest that at least a subset of mantle cell lymphoma cases have undergone some form of antigene selection, and particular types of Ig gene rearrangement seem to give a better prognosis. The cell cycle, the ATM, gene and the nuclear factor kappaB pathways are the main targets of the genetic abnormalities occurring in mantle cell lymphoma: new genomic and expression data have been recently published. Unfortunately, this progress has not yet brought any major improvements in therapeutic approaches, which still remain highly unsatisfactory. Autologous and allogenic bone marrow transplantations appear to be the only current treatments that might improve the outcome of patients with PMCL. New additional treatment modalities are currently under investigation.

SUMMARY

This review summarizes all the most recent data published on the biology and treatment of mantle cell lymphoma.