Comparison of interferon tolerance after autologous bone marrow or peripheral blood stem cell transplants for myeloma patients who have responded to induction therapy

Future challenges

Treatment for patients with myeloma has changed unrecognisably over the last two decades and now includes a sequence of treatments including chemotherapy, biological targeted therapy with or without consideration for high-dose therapy (autologous and allogeneic stem cell transplantation for younger and fit patients). As patients can now expect a doubling of median survival and a 20-30% chance of surviving longer than 10 years, the focus of treatment is shifting to long-term quality of life. This article focuses on future challenges facing clinicians treating myeloma and how best we may optimize our resources.

The role of cytotoxic therapy with hematopoietic stem cell transplantation in the therapy of multiple myeloma: an evidence-based review

Evidence supporting the role of hematopoietic stem cell transplantation (SCT) in the therapy of multiple myeloma (MM) is presented and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published medical literature and for grading the quality of the evidence, the strength of the evidence, and the strength of the treatment recommendations. Treatment recommendations based on the evidence presented in the review were made unanimously by a panel of MM experts. Recommendations for SCT as an effective therapy for MM include the following: SCT is preferred to standard chemotherapy as de novo therapy; SCT is preferred as de novo rather than salvage therapy; autologous peripheral blood stem cell transplantation (PBSCT) is preferred to bone marrow transplantation (BMT); and melphalan is preferred to melphalan plus total body irradiation as the conditioning regimen for autologous SCT. Recommendations that SCT is not effective include the following: current purging techniques of bone marrow. Recommendations of equivalence include the following: PBSCT using CD34+ selected or unselected stem cells. No recommendation is made for indications or transplantation techniques that have not been adequately studied, including the following: SCT versus standard chemotherapy as salvage therapy, tandem autologous SCT, autologous or allogeneic SCT as a high-dose sequential regimen, allogeneic BMT versus PBSCT, a preferred allogeneic myeloablative or non-myeloablative conditioning regimen, and maintenance therapy post-autologous SCT with interferon alpha post-SCT. The priority area of needed future research is maintenance therapy posttransplantation with nothing versus interferon alpha versus other agents such as corticosteroids or thalidomide or its derivatives.

Response to induction chemotherapy is not essential to obtain survival benefit from high-dose melphalan and autotransplantation in myeloma

Two hundred and twenty-two myeloma patients autografted after 200 mg/m(2)melphalan were studied to examine the relationship between response to induction chemotherapy and outcome. Induction comprised cyclophosphamide, vincristine, doxorubicin and methylprednisolone (C-VAMP) every 3 weeks for one cycle beyond maximum response. 81% responded to C-VAMP (chemosensitive) with 40 complete (CR) and 139 partial (PR) remissions, and 43 did not respond (NR; <50% reduction in paraprotein; primary refractory). Overall, 130 patients (59%) attained or remained in CR post-transplant; including 40% of NR, 53% of PR, and 97% of CR after C-VAMP (P < 0.0001). Amongst these 130 patients, the 5-year OS was independent of response to C-VAMP (NR 79%, PR 74%, CR 60%; P = 0.69). Similarly, among the 69 patients in PR post-transplant, the 5-year OS was independent of response to C-VAMP. In Cox analysis, lack of response to C-VAMP did not affect outcome significantly. These data show that lack of response to induction therapy does not automatically predict poor long-term outcome in myeloma, since a substantial proportion of these patients attain CR after autograft and enjoy extended survival. Myeloma patients should not be disqualified from an autograft based upon lack of response to induction chemotherapy.

Delayed stem cell transplantation for the management of relapsed or refractory multiple myeloma

The optimal timing of stem cell transplantation for multiple myeloma is controversial. Late stem cell collection is undesirable because of the inability to mobilize stem cells. We report on 64 recipients of stem cells collected within 1 year after diagnosis, none of whom had transplantation in plateau phase of their disease. Patients seen within 12 months after diagnosis received four cycles of standard vincristine, doxorubicin, and dexamethasone (VAD) chemotherapy and then had stem cells mobilized. Patients were then placed on maintenance vincristine, BCNU, melphalan, cyclophosphamide, and prednisone or melphalan and prednisone chemotherapy for 12 cycles. At the sign of first progression, transplantation occurred. Fourteen patients were refractory to VAD chemotherapy, 20 relapsed on maintenance chemotherapy, and 30 relapsed off chemotherapy. The time to platelet engraftment was not affected by the duration of stem cell cryopreservation or extent of chemotherapy exposure after mobilization. The complete response rate was 34%. The actuarial median survival from initial diagnosis, from transplant day 0, and post-transplant progression-free survival was 51, 20 and 11.4 months, respectively. The patient status at transplantation and percentage of plasma cells circulating in the blood at apheresis influenced post-transplant survival; circulating plasma cells, status at transplantation and plasma cell labeling index influenced progression-free survival. Response duration was shorter in patients relapsing on chemotherapy.

Acute lymphoblastic leukaemia-type intensive chemotherapy to eliminate minimal residual disease after high-dose melphalan and autologous transplantation in multiple myeloma - a phase I/II feasibility and tolerance study of 17 patients

Aiming to target the minimal residual disease in patients with multiple myeloma, a phase I/II single centre study was undertaken for feasibility and tolerance of intensive acute lymphoblastic leukaemia consolidation chemotherapy (ALL-IC) as part of a strategy for post-transplant consolidation targeted at pre-B cells. Seventeen newly diagnosed patients with myeloma (median age 55 years; 30-65) were initially treated with courses of infused cyclophosphamide, vincristine, adriamycin and methylprednisolone (C-VAMP) followed by melphalan 200 mg/m2(HDM) and peripheral blood stem cell rescue (PBSC). Forty-seven percent were in CR and the rest in PR after HDM. ALL-IC consisted of vincristine, daunorubicin, etoposide, cytarabine, 6-thioguanine and prednisolone given over 5 days. All patients became neutropenic (<0.5 x 109/l) at a median of 10 days (4-18) and one of the 17 patients (5.8%) died 15 days post ALL-IC of sepsis. A further four have died of relapse with an overall survival (OS) of 67% at 4 years. Two of nine patients in PR at the time of ALL-IC achieved CR. Matched-pair analysis of 34 control patients shows no difference for OS and event-free survival between ALL-IC and controls. We conclude that ALL-IC given to myeloma patients after HDM/PBSC is as safe as when used in ALL and warrants further assessment in randomised trials for myeloma.

Comparison of marrow vs blood-derived stem cells for autografting in previously untreated multiple myeloma

Sixty-three new untreated patients with multiple myeloma under the age of 70 years received C-VAMP induction treatment followed by high-dose intravenous melphalan (200 mg m(-2)) and autologous stem cell transplant, either with marrow [autologous bone marrow transplants (ABMT), n = 26] or with granulocyte colony-stimulating factor (G-CSF)-mobilized stem cells from the blood [peripheral blood stem cell transplants (PBSCT), n = 37]. This was a sequential study and the two groups were not significantly different for all known prognostic variables. The complete remission (CR) rate after high-dose treatment was the same for both groups [ABMT 84% and PBSCT 70%; P = not significant (NS)]. Neutrophil recovery to 0.5 x 10(9) l(-1) occurred at a median of 22 days in the ABMT patients compared with 19 days for the PBSCT patients (P = NS). Platelet recovery to 50 x 10(9) l(-1) was significantly faster in PBSCT patients (19 days vs 33 days; P = 0.0015), and the PBSCT patients spent fewer days in hospital (median 20 vs 27 days; P = 0.00001). There was no difference in the two groups with respect to starting interferon (58 days for ABMT vs 55 days for PBSCT), and tolerance to interferon was identical. The median overall survival (OS) and progression-free survival (PFS) for the PBSCT patients has not yet been reached. The OS in the ABMT patients at 3 years was 76.9% (95% CI 60-93%) compared with 85.3% (95% CI 72-99%) in the PBSCT patients (P = NS), and the PFS at 3 years in the ABMT patients was 53.8% (95% CI 34-73%) and in the PBSCT patients was 57.6% (95% CI 34-81%) (P = NS). The probability of relapse at 3 years was 42.3% in the ABMT arm compared with 40% in the PBSCT patients (P = NS). Thus, PBSCT patients had a faster engraftment and a shorter stay in hospital than ABMT; the survival outcome and probability of relapse was the same for both groups.