VAD-based regimens as primary treatment for multiple myeloma

Relapsed multiple myeloma

The treatment of relapsed multiple myeloma remains a challenge for clinicians. Most salvage therapies result in transient responses, with median survival from relapse ranging from 6 to 18 months. No randomized trials comparing salvage therapies have been performed. In the absence of a "gold standard" salvage therapy, relapsed patients should be considered for clinical trials. In light of the recent observation that thalidomide alone brings about a 30% to 35% response rate with manageable toxicities, this is the most promising single agent available to treat relapsed disease. The maximum effective dose appears to be 400 mg/d; virtually all responses are evident within 2 months of starting therapy. Combination therapy of thalidomide with pulse dexamethasone or other chemotherapeutic agents has shown promise in pilot trials. Even with thalidomide-responsive disease, the response duration is brief, ranging from 3 to 6 months. Therefore, the authors recommend that patients under the age of 78 years who have acceptable physiologic organ function, chemotherapy-sensitive disease, third-party financial coverage, and adequate hematopoietic stem cells be considered for high-dose therapy with autologous hematopoietic stem cell transplant. High-dose therapy with hematopoietic stem cell transplant provides the highest response rate, response duration, and survival compared with historical controls treated with conventional therapy. Patients under the age of 70 years who have human leukocyte antigen-compatible donors should be considered for immune-based therapy using nonmyeloablative preparative regimens with allogeneic hematopoietic stem cell transplant.

Solitary plasmacytoma treated with radiotherapy: impact of tumor size on outcome

PURPOSE

Solitary plasmacytoma (SP) is a rare presentation of plasma cell neoplasms. In contrast to multiple myeloma, long-term disease-free survival and cure is possible following local radiotherapy (RT), particularly for soft tissue presentations. In this study, we attempt to identify factors that predict for local failure, progression to multiple myeloma, and disease-free survival (DFS) in patients mainly managed with local RT.

METHODS AND MATERIALS

We identified 46 patients referred to the Princess Margaret Hospital between 1982 and 1993. The median age was 63 years (range 35-95), with a male:female ratio of 1.9:1. All patients had biopsy-proven SP (osseous: 32, soft tissue: 14). M-protein was abnormal in 19 patients (41%). All patients were treated with local RT (median dose 35 Gy), with 5 patients (11%) also receiving chemotherapy. Maximum tumor size pre-RT ranged from 0 to 18 cm (median 2.5).

RESULTS

The 8-year overall survival, DFS, and myeloma-free rates were 65%, 44%, and 50%, respectively. The local control rate was 83%. Factors predictive of progression to myeloma (and poorer DFS) included bone presentation and older age. However, these two factors did not influence local control, which was affected by tumor size. All tumors < 5 cm in bulk (34 patients) were controlled by RT. Anatomic location did not predict outcome; however, 3 of the 5 tumors arising in paranasal sinuses did not achieve local control. Lower RT dose (< or =35 Gy) was not associated with a higher risk of local failure.

CONCLUSION

Solitary plasmacytomas are effectively treated with moderate-dose RT, although osseous tumors have a high rate of recurrence as systemic myeloma. Large tumor bulk locally (> or =5 cm) predicts for local failure. Combined chemotherapy and RT should be investigated in these high-risk patients to increase the local control rate and the cure rate.

Impact of complete remission with intensive therapy in patients with responsive multiple myeloma

Clinical outcomes were assessed in 68 consecutive patients with multiple myeloma of high or intermediate tumor mass that had responded to VAD or dexamethasone-based therapy and were consolidated with early intensive therapy and autologous stem cell transplantation. Results were compared with those of 50 comparable patients who refused or were unable to receive intensive treatment for socioeconomic reasons. Following high-dose therapy, the rate of CR increased from 6 to 37%, with median survival prolonged by 10 months. Survival of 21 patients with disease converted from PR to CR (median 8.3 years) was significantly longer than that of similarly-treated patients who remained in PR (median 5.0 years). CR of myeloma represents the major surrogate marker of long survival and the primary goal of myeloablative treatment for patients in PR. Twelve of 18 patients with rapid reduction of myeloma protein (T(1/2) < 0.5 months), and myeloma protein reduction to <1.0 g/dl after primary therapy achieved CR (67%), identifying pretransplant features favorable to intensive therapy. Among 35 patients with slower reduction or higher residual myeloma protein, CR occurred in eight patients (23%) (P < 0.01), for whom other treatments should be considered. The kinetics of response to initial therapy should be considered in selecting patients more likely to achieve CR and consequent long survival after intensive treatment.

Cyclophosphamide, adriamycin and dexamethasone (CAD) is a highly effective therapy for patients with advanced multiple myeloma

BACKGROUND

Patients with advanced multiple myeloma (stage III or progressive myeloma) received the CAD protocol every three weeks: cyclophosphamide 200 mg/m2 i.v./orally days 1-4, adriamycin 30 mg/m2 i.v. on day 1 and dexamethasone 40 mg p.o. days 1-4.

PATIENTS AND METHODS

Forty-six patients with a median age of sixty years (range 34-84 years) were enrolled. According to Durie-Salmon 44 patients were in stage III, 2 in stage II; 6 patients had renal insufficiency (stage B). Twenty-three patients were pre-treated at least with melphalane/prednisone.

RESULTS

Remission rates were as follows: complete remission 4%, partial remission 70%, minimal change 11%, no change 11%, progressive disease 4%. After an observation time of 14 months the median progression free interval for 33 patients not treated with subsequent high-dose chemotherapy with stem-cell support was more than 14 months. Overall, treatment was well tolerated. After 209 cycles given febrile neutropenia occurred in 11% of cycles including one fatal outcome. Neutropenia or thrombocytopenia grade 3-4 WHO was recorded in 18% and 6% of the cycles, respectively.

CONCLUSIONS

This study shows that CAD is an effective regimen with an overall remission rate of 74%. The CAD protocol should be further evaluated in prospective trials.

Chemotherapy and granulocyte colony stimulating factor-mobilized blood cell infusion followed by interferon-alpha for relapsed malignancy after allogeneic bone marrow transplantation

BACKGROUND

Interferon-alpha (IFN) is known to promote graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (allo BMT). This property may also be used to enhance a graft-versus-leukaemia effect (GVL) after donor leucocyte infusion (DLI), a mode of therapy increasingly offered to patients relapsing after allo BMT.

AIM

The aims of the present study were to examine the efficacy and toxicity of IFN therapy administered after granulocyte colony-stimulating factor (G-CSF)-stimulated blood cells given as DLI in patients with acute myeloid leukaemia (AML), chronic myeloid leukaemia (CML), acute lymphoblastic leukaemia (ALL), acute undifferentiated leukaemia (AUL) and multiple myeloma relapsing after allo BMT.

METHODS

Between October 1996 and September 1999, 27 patients (16 AML, four ALL, three CML, three multiple myeloma, one AUL) who relapsed after allo BMT were treated with chemotherapy followed by DLI, collected after G-CSF stimulation in all but two cases. Subsequently, IFN was given to patients without significant GVHD or rapidly progressive disease. The outcome after DLI with regard to remission rate, disease-free survival and GVHD was analysed.

RESULTS

Eighteen patients received IFN following DLI, 14 of whom developed significant GVHD (grade II-IV acute or extensive chronic); thereafter, GVHD resolved with cessation of IFN alone in four patients, but 10 required systemic immunosuppression. Twenty-three patients were given chemotherapy and DLI as initial treatment of relapse; 10 achieved complete remission (CR), in four patients this was only after the onset of GVHD. The other four patients received chemotherapy and DLI as a consolidation of a chemotherapy-induced remission. The CR was durable only in patients with CML (3 of 3) and AML (4 of 8).

CONCLUSIONS

Treatment with IFN induced GVHD in the majority of patients receiving DLI. The induction of GVHD and GVL by this approach produced excellent results in patients with CML and modest results in AML, but appeared to be less effective in myeloma and ALL.

Randomized trial of alpha-interferon or dexamethasone as maintenance treatment for multiple myeloma

In order to assess the role of alpha-interferon or dexamethasone as maintenance therapy for multiple myeloma, 172 consecutive, previously untreated patients with disease of low or intermediate tumor mass received primary therapy with oral melphalan and intermittent, high-dose dexamethasone (MD), repeated monthly. Within 5 months, 84 responding patients were assigned at random to maintenance treatment with alpha-interferon (3 mU s.c. 3 x weekly) or dexamethasone (20 mg/m2 p.o. each morning for 4 days) repeated monthly until relapse. Upon relapse, MD was resumed for 2 cycles and second responses were maintained with 4-day courses of melphalan-dexamethasone until second relapse. Initial response was achieved in 88 patients (51%) after a median 0.7 month and no more than 3 courses of MD, a frequency of response similar to that observed previously with dexamethasone alone. There were identical median remissions of 10 months with interferon or dexamethasone, both maintenance regimens being associated with infrequent, mild, and reversible side effects. Significantly more patients responded again to resumption of MD after disease relapse to interferon (82%) than to dexamethasone (44%) (P = 0.001). The median remission from randomization to melphalan-resistant second relapse was 32 months for patients maintained initially on interferon compared to 19 months for those on dexamethasone (P = 0.01). These findings supported an advantage for interferon in remission maintenance by increasing the frequency of tumor recontrol with later treatment that included dexamethasone.

Management of renal complications in patients with advanced multiple myeloma

Although the kidney is frequently involved in malignant monoclonal gammopathy, the clinical outcome of the patients varies considerably. We retrospectively assessed the clinical course in seventeen patients with acute and chronic renal failure suffering from multiple myeloma, and analyzed their case history focusing on the therapeutic management, the possible clinical improvement as well as the patients' outcome. Treatment included chemotherapy (n = 17), forced diuresis (n = 3), hemodialysis (n = 11, 7 chronic, 4 intermittent) and plasmapheresis (n = 3). Renal function improved in five patients, and was stabilized compensated in four. Seven patients developed end-stage renal disease, one refused further treatment and was lost for follow up. In addition to renal failure, the most frequent complications included local bone destruction (all), anemia (n = 12), low platelet count (n = 11), and bacterial infections (n = 9). One year survival rate after admission to the nephrology department was 76 percent. Chemotherapy in combination with renal replacement therapy may improve the clinical course even in MM patients with serum creatinine levels above 3.0 mg/dL or end-stage renal disease.

Safety of autologous hematopoietic stem cell transplantation in patients with multiple myeloma and chronic renal failure

Patients with multiple myeloma (MM) and chronic renal failure have generally been excluded from myeloablative therapy programs followed by hematopoietic stem cell support because of the potential increase in transplant-related morbidity and mortality. We here report our experience treating six MM patients with moderate to severe renal insufficiency, with autologous stem cell transplantation. One of these patients required chronic hemodialysis since the diagnosis of MM was made. Peripheral blood stem cell collection was performed with either cyclophosphamide 5.5-7 g/m2 + G-CSF, 5 microg/kg/day (patients 1-3, 5 and 6) or G-CSF, 15 microg/kg/day alone (patient No. 4). Four patients (Nos 1-4) received autotransplant as front-line therapy, while the last two patients were treated in relapse, which occurred following prior autologous stem cell transplantation in support of melphalan, 200 mg/m2 (No. 5) or maintainance therapy with alpha-interferon (No. 6). High-dose chemotherapy administered as preparation to transplant included busulfan 12 mg/kg + melphalan 80 mg/m2 (patients 1-3 and 6) or melphalan 80 mg/m2 alone (patients 4 and 5) in order to reduce mucosal damage. Following transplant, prompt and sustained recovery of hematopoiesis was documented in all the patients; 500 PMN/microI and 20000 platelets/microI were reached after a median of 13 and 14 days, respectively. None of the patients suffered from WHO grade 3-4 infectious complications. Transplant-related toxicity included grade 3-4 oral mucositis (patients 1, 4 and 5) and veno-occlusive disease (patient No. 3). Renal function either improved or remained stable throughout the transplant period. All the patients but one responded to therapy, three of them are progression free after 2, 15 and 26 months; two relapsed after 16 and 4 months and one died from cholangiocarcinoma 7 months after transplant, while still in remission. Although our experience is limited so far, these results appear promising and support the investigational use of myeloablative therapy in MM patients with chronic renal failure.

Transplantation with selected autologous peripheral blood CD34+Thy1+ hematopoietic stem cells (HSCs) in multiple myeloma: impact of HSC dose on engraftment, safety, and immune reconstitution

OBJECTIVE

The aims of our study performed in myeloma were to evaluate the performance and the safety of Systemix's high-speed clinical cell sorter, to assess the safety and efficacy of deescalating cell dose cohorts of CD34+Thyl+ hematopoietic stem cells (HSCs) as autologous grafts by determining engraftment, and to assess the residual tumor cell contamination using polymerase chain reaction (PCR) amplification assays of patient-specific complementarity determining region III (CDR III) analysis for residual myeloma cells.

MATERIALS AND METHODS

The clinical trial was performed in 31 multiple myeloma patients, using purified human CD34+Thyl+ HSCs mobilized from peripheral blood with cyclosphosphamide and granulocyte-macrophage colony-stimulating factor to support a single transplant after high-dose melphalan 140 mg/m2 alone (cohort 1) and with total body irradiation (TBI) (cohorts 2-5) after an HSC transplant cell dose de-escalation/escalation design.

RESULTS

Twenty-three patients were transplanted. Engraftment data in the melphalan + TBI cohorts confirmed that HSC doses above the threshold dose of 0.8 x 10(6) CD34+Thy1+ HSCs/ kg provided prompt engraftment (absolute neutrophil count >0.5 x 10(9)/L day 10; platelet count >50 x 10(9)/L day 13). A higher rate of infections was observed in the early and late follow-up phases than usually reported after CD34+ selected or unselected autologous transplantation, which did not correlate with the CD34+Thy1+ HSC dose infused. Successful PCR for CDR III could only be performed in five patients on initial apheresis product and final CD34+Thy1+ HSC product and showed a median tumor log reduction >3.12.

CONCLUSIONS

CD34+Thy1+ HSCs are markedly depleted or free of detectable tumor cells in multiple myeloma and are capable of producing fast and durable hematopoietic reconstitution at cell doses >0.8 x 10(6) CD34+Thy1+ HSCs/kg. The delayed immune reconstitution observed is not different from that described in unselected autologous bone marrow and peripheral blood mononucleated cells transplants in multiple myeloma and may be corrected by addition of T cells either to the graft or to the patient in the posttransplant phase.

Cyclophosphamide, etoposide, vincristine, adriamycin, and dexamethasone (CEVAD) regimen in refractory multiple myeloma: an International Oncology Study Group (IOSG) phase II protocol

A 4- day continuous intravenous (CIV) infusion of vincristine and doxorubicin with high-dose dexamethasone (VAD) regimen is a standard refractory multiple myeloma (MM) regimen. A Phase II study of a CEVAD regimen, i.e., VAD plus etoposide administered as a 96-hr continuous infusion, was carried out with IV bolus cyclophosphamide. Thirty-six patients were treated on study and received a total of 114 cycles of CEVAD: median 2 cycles (range 1-8). No patient achieved a CR. The overall rate of PR was 15/36 (42%). Patients achieved maximal response after a median of 4 (range 3-6) courses. PR rates were 40% (4/10) in patients with primary refractory disease, 48% (11/23) in patients with secondary refractory disease, 31% (6/19) in patients who had failed previous VAD therapy, and 50% (7/14) in patients receiving 2nd or subsequent relapse therapy. Three patients died during their initial cycle of therapy from rapidly progressive disease and sepsis. Overall median survival was 24 weeks with a 1-year survival of 33.3% ¿95% confidence interval of 20-46%¿. Myelosuppression was the most frequent adverse event with NCI grade 2 neutropenia and/or thrombocytopenia in 15% of first cycles, grade 3 in 20%, and grade 4 in 65%. Two-thirds of patients had at least one episode of grade 3 or 4 sepsis. In 15% of septic episodes positive blood cultures were obtained. Overt cardiotoxicity was seen in two patients. CEVAD as used in this study was not more effective than VAD in terms of overall response rate or survival.

Clinical course of solitary extramedullary plasmacytoma

BACKGROUND AND PURPOSE

Solitary extramedullary plasmacytoma (EMP) represents a rare category of malignant disease on which there are limited data in regard to diagnosis, staging and natural history. This study attempted to clarify the clinical course of solitary extramedullary plasmacytoma after radiation or surgical therapy given with curative intent.

MATERIALS AND METHODS

The diagnosis was based on a mass of clonal plasma cells separate from bone or bone marrow without evidence of occult disease elsewhere. Between 1963 and 1996, 22 previously untreated patients with an EMP were diagnosed. Disease presented in the head or neck in 86%, usually in the nasal cavity (NC) or maxillary sinus (MS), and in these areas local bone destruction was found in 10 of 11 patients. Among all patients, serum myeloma protein was present in three patients (14%) and Bence Jones protein alone was found in two patients (9%). Radiation therapy was the sole treatment for 18 of 22 patients, and the median radiotherapy dose was 50 Gy (range, 40-60 Gy); five of seven patients with an EMP of oral cavity (OC), oropharynx (OP), nasopharynx (NP), parotid or larynx also received elective neck irradiation. Two patients underwent surgery plus postoperative irradiation of a plasmacytoma of the sigmoid colon or pleura, and two patients had resection alone of a plasmacytoma of the colon or cervical lymph node.

RESULTS

Local control was achieved in 21 of 22 patients (95%), and disease never recurred in regional nodes. Disappearance of myeloma protein occurred in three of five patients with an evaluable abnormality. Multiple myeloma developed in seven patients (32%), all within 5 years. The 5-year rate of freedom from progression to multiple myeloma was 56% and the median survival was 9.5 years.

CONCLUSION

Radiation therapy achieved excellent locoregional control of EMP with an approximate cure fraction of 50%.

[Standard treatment of multiple myeloma]

INTRODUCTION

About 50% of patients with multiple myeloma are older than 65 years and are not eligible for high-dose therapy, which has proved to be more efficacious than standard-dose chemotherapy in young patients.

CURRENT KNOWLEDGE AND KEY POINTS

Apart from high-dose therapy, no clear therapeutic advance has been achieved in the past 20 years, and melphalan-prednisone combinations remain reference treatments for many patients with multiple myeloma. Despite a great number of clinical trials, the use of interferon alpha is still controversial. The role of high-dose dexamethasone has been recently established and we are currently comparing dexamethasone alone, melphalan-dexamethasone and dexamethasone-interferon alpha treatments in a multicenter randomized trial (IFM 95-01). Bisphosphonates have also emerged as an efficacious and well tolerated adjuvant treatment. Optimal use of recently released bisphosphonates at various stages of the disease will possibly lead to a clear therapeutic advantage.

FUTURE PROSPECTS AND PROJECTS

Other drugs, such as erythropoietin or interferon gamma require further evaluation. The recent implication of metalloproteinases in multiple myeloma and the efficacy of metalloproteinase inhibitors in animal models and phase I/II clinical studies in solid tumors provide a strong rationale for the clinical evaluation of these agents in multiple myeloma.

Current drug therapy for multiple myeloma

Recent years have witnessed tremendous advances in the molecular pathogenesis and management of multiple myeloma. Standard chemotherapy (melphalan and prednisone; MP) has been the mainstay of treatment of multiple myeloma for about 3 decades. However, it is no longer considered the 'gold standard', particularly for those patients who will subsequently undergo intensive chemotherapy with autologous or allogeneic peripheral blood stem cell (PBSC) or bone marrow transplantation (BMT), or for patients with refractory myeloma. A variety of induction combination chemotherapy regimens have been developed, some of which have demonstrated an improved response rate and duration and a superior 5-year survival rate when compared with standard chemotherapy. The early use of high dose chemotherapy with autologous PBSC support or BMT has significantly increased the complete remission rate, and has prolonged event-free sur vival and overall survival. Allogeneic bone marrow or PBSC transplantation may be a good option for selected patients with poor prognostic features. The role of interferon-alpha in multiple myeloma is still inconclusive despite many years of clinical evaluation. The clinical application of chemosensitising agents that can inhibit P-glycoprotein (P-gp) expression and function, and particularly the development of more potent P-gp modulators such as valspodar (PSC 833) and elacridar (GF120918) has made it possible to reverse multidrug resistance in some refractory patients and to enhance the efficacy of chemotherapeutic agents. Immunotherapeutic approaches to purging of autologous bone marrow or PBSC, or as adjuvant therapy for minimal residual disease, show great promise. Finally, a number of new therapies specifically designed to treat many of the complications of multiple myeloma are improving clinical outcomes and quality of life for these patients.

Dexamethasone plus retinoids decrease IL-6/IL-6 receptor and induce apoptosis in myeloma cells

Interleukin 6 (IL-6) is the most important known growth factor for multiple myeloma, and IL-6 signalling pathways are potential targets for therapy. We hypothesized that interfering with the IL-6 signalling pathway at more than one level would be more effective than a single block in inhibiting proliferation of myeloma cells. Accumulating data support the concept that glucocorticoids down-regulate IL-6, whereas retinoic acid derivatives (RA) down-regulate IL-6R in myeloma. We found that all-trans RA (ATRA), 13-cis-RA and 9-cis-RA each similarly inhibited growth of RPMI 8226 myeloma cells and that addition of dexamethasone (DEX) added to RA growth inhibition. The major effects of retinoids were to reduce the proliferative fraction and induce apoptosis whereas DEX increased the apoptotic fraction. When combined, apoptosis was enhanced. Effects of RA + DEX were also least able to be overcome by exogenous IL-6. RA decreased IL-6R levels and addition of DEX to RA delayed recovery of IL-6R levels compared with RA alone. Since RPMI 8226 cells have undetectable IL-6, we investigated U266B1 cells and found that RA and DEX decreased both IL-6 secretion and IL-6 RNA levels. Mechanistically, IL-6R down-regulation by RA was enhanced by DEX, whereas IL-6 protein and RNA levels were reduced by DEX and by RA. In summary, combinations of RA + DEX were not only more effective in inhibiting myeloma cells growth by the dual mechanisms of decreasing proliferative fraction and increasing apoptotic fraction, but were also less able to be overcome by IL-6.

Solitary bone plasmacytoma: outcome and prognostic factors following radiotherapy

PURPOSE

To clarify the natural history of solitary plasmacytoma of bone (SBP) after radiation treatment.

METHODS AND MATERIALS

Between 1965-1996, we identified 57 previously untreated patients with a SBP. A serum myeloma protein was present in 33 patients (58%) and Bence Jones proteinuria was present in an additional eight patients (14%). The median radiotherapy dose was 50 Gy (range, 30-70 Gy). Overall survival, cause-specific survival, and freedom from progression to multiple myeloma were calculated actuarially.

RESULTS

Local control was achieved in 55 of 57 patients (96%). For those 29 patients (51%) who subsequently developed multiple myeloma, the median time to progression was 1.8 years. There was a direct correlation between persistence of abnormal protein following radiotherapy and the likelihood of developing multiple myeloma. Among 11 patients with disappearance of myeloma protein, only two developed multiple myeloma after 4 and 12 years, in contrast to progression in 57% of patients with a persistent protein peak and 63 % of those with nonsecretory disease (p = 0.02). Among 23 patients with thoracolumbar spine disease, 7 of 8 patients staged with plain radiographs alone developed multiple myeloma in comparison with 1 of 7 patients who also had magnetic resonance imaging (MRI) (p = 0.08). For all patients, the median survival from radiotherapy was 11.0 years. The median cause-specific survival of patients with disappearance of myeloma protein was significantly longer than that of the remaining patients (p = 0.004).

CONCLUSION

Results supported the importance of precise staging that includes MRI of the spine for optimum patient selection and the application of definitive radiotherapy. Those patients with myeloma protein that disappears following radiotherapy represent a category with a high likelihood of cure.

Management of Myeloma: Current and Future Approaches

BACKGROUND: The treatment of multiple myeloma, relatively stagnant for many years, appears to be entering a promising era for improvement. This paper reviews treatment interventions available for patients with multiple myeloma to indicate a standard approach and to evaluate the spectrum of current standard therapy. METHODS: The author reviews published literature on the treatment of multiple myeloma. Both journal articles and papers presented at national and international meetings are utilized. RESULTS: Intensive combination chemotherapy offers relatively modest improvement over standard melphalan plus prednisone, but the use of interferon for maintenance therapy lengthens response duration and possibly survival. High-dose chemotherapy with stem-cell transplantation is a relatively safe and effective treatment modality for patients under 70 years of age at first relapse. Studies in progress will determine its role in first response consolidation. Use of hematopoietic growth factors, prophylactic antibiotics, and bisphosphonate treatment of lytic bone disease has diminished disease morbidity. CONCLUSIONS: While cure of multiple myeloma remains elusive and 10-year survival is still uncommon, newer treatment approaches offer better control of disease manifestations and perhaps a real opportunity to prolong functional life. Future treatments that will address minimal residual disease may improve long-term survival.

Anthracyclines in haematology: pharmacokinetics and clinical studies

The activity of anthracyclines in the treatment of a wide spectrum of haematological malignancies has long been established. Differences in the pharmacokinetic and pharmacodynamic properties of these drugs have resulted in the selection of individual compounds for particular indications while the recent reformulation of anthracyclines in liposomal preparations seems likely to significantly alter their range of activity and toxicity. The problems related to cumulative cardiotoxicity secondary to anthracycline exposure can be ameliorated by the use of dexrazoxane and a number of agents may prove to have a role in altering their cellular resistance to their cytotoxic actions.

Therapeutic management of hematological malignancies in elderly patients. Biological and clinical considerations. Part IV: Multiple myeloma and Waldenström's macroglobulinemia

Following recent data on multiple myeloma (MM) in the literature, a possible model of myeloma development, involving different cytokine signals, is advanced, and the prognostic significance of two principle staging systems is evaluated. Different therapeutic approaches to MM have been employed, consisting of either treatment with only melphalan and prednisone, or combination chemotherapy, especially in patients with a poor prognosis. However, for the initial therapy, melphalan plus prednisone in doses that compensate for individual variation in drug absorption still appears the best choice in the vast majority of MM patients. The main clinical and hematological features which distinguish Waldenström's macroglobulinemia from MM are described, as are the criteria which should be used in choosing the most appropriate treatment based, when necessary, on chemotherapy with standard alkylating agents, as well as on the new nucleoside analogues, and repeated courses of plasmapheresis.

Treatment of multiple myeloma in elderly patients. New developments

The median of survival among patients with multiple myeloma (MM) is about 30 months from the onset of treatment. Tumour burden and a range of other parameters, such as C-reactive protein levels, the plasma cell labelling index and beta2-microglobulin levels, can be used to assign patients to favourable and unfavourable prognostic groups. Conventional chemotherapy consists of melphalan and prednisone, and is as effective as moderately intensive cytotoxic drug regimens. Although second-line chemotherapy is initially effective, all patients eventually die. Maintenance therapy will interferon-alpha prolongs the plateau phase of the disease, but its effects on overall survival are minimal. One of the promising developments in the treatment of MM has been the introduction of high dosage chemotherapy, which can now be safely administered when stem cells are used for haematological recovery. Autologous bone marrow transplantation has been shown to produce a significant improvement in survival compared with conventional therapy. Several studies are under way that are examining the effects of multiple courses of high dosage chemotherapy together with peripheral stem cell support. Purging of autologous stem cell harvests will be performed in the near future to minimise contamination with myeloma cells. It is now feasible to use high dosage chemotherapy, with the support of granulocyte colony-stimulating factor-stimulated whole blood, in selected elderly patients. Besides the promising development of intensive therapy, a number of other treatment strategies have emerged, including treatment with monoclonal antibodies against interleukin-6 and multidrug resistance-modulating agents. Better supportive care can be provided for some patients by using epoetin (recombinant human erythropoietin), and the sequelae of lytic bone lesions can be ameliorated through the use of bisphosphonates.

Maintenance therapy with alpha-interferon following first-line VAD in multiple myeloma

The aim of this study was to evaluate the response characteristics of vincristine, adriamycin and dexamethasone (VAD) as a first-line chemotherapy and to determine the efficacy of maintenance alpha-interferon (alpha-IFN) in multiple myeloma (MM). Between January 1985 and December 1994, a prospective trial was performed in stage II and III MM patients. The study population received only VAD with no maintenance therapy before 1990 (n=31), and those recruited after 1990 (n=33) were planned to be maintained with alpha-IFN (5 mU, 3 times per wk) during the plateau to a maximum of 2 yr. Median follow-up duration (44 vs. 39 months), time to response (3.4 vs. 3.5 months) and rate of objective response (61.3%, 19/31 and 63.6%, 21/33) were similar in VAD-only and VAD+IFN groups, respectively. The survival analyses revealed higher median progression-free (39.6 vs. 12 months) and overall survival (65+ vs. 24 months) durations in VAD+IFN group compared to VAD-only group. VAD regimen was well tolerated and IFN-related side effects were reversible. These findings denote that IFN maintenance prolongs the duration of response obtained by VAD.

Allogeneic stem cell transplantation for multiple myeloma

High-dose chemotherapy (with or without total body irradiation) followed by allogenic marrow transplantation is curative for some patients with advanced multiple myeloma. A relatively high transplant-related mortality, however, limits the wider application of this approach. The challenge for future studies will be to develop less toxic preparative regimens, more efficient ways to prevent infection and graft-versus-host disease, and methods to enhance the graft-versus-leukemia effect of allografts.

Diagnosis, prognosis, and standard treatment of multiple myeloma

The diagnosis of multiple myeloma (MM) is often difficult; most patients present with asymptomatic gammopathy. The only findings that confirm a diagnosis of MM are an elevation in the M-component or extension of the lytic bone lesions that are the hallmark of the disease. Tests that delineate plasma cell biology, such as plasma cell proliferation rate, are helpful; magnetic resonance imaging can disclose bone marrow lesions leading to subsequent osteolytic disease. After the diagnosis of MM has been established and prognostic factors identified, the appropriate therapy can be determined. Melphalan and prednisone are no longer considered to be the "gold standard" of therapy. In fact, this approach is suitable for less than half of patients with myeloma. This article presents guidelines for standard treatment options and examines the efficacy of new high-dose chemotherapy approaches.

Maintenance therapy with interferon-alpha (IFN-alpha) versus IFN-alpha plus chemotherapy in multiple myeloma (MM). The Greek Myeloma Study Group

Results of studies using IFN-alpha treatment for maintaining remission and prolonging survival in multiple myeloma (MM) are in conflict and trials seeking optimum use for this biological response modifier are continuing. Between 1989 and 1993 a prospective randomized multicentre trial was undertaken to evaluate the role of the combination of IFN-alpha with chemotherapy (CT) in maintenance treatment of MM. For remission induction, in patients 65 yr or younger, we used VAD (group A) and for the remaining Melphalan and Prednisone (MP) (group B). For maintenance, patients were randomized to receive IFN-alpha 3 x 10(6) i.u. s.c. t.i.w. (group I) or alternating monthly cycles of IFN-alpha and CT. The CT cycles were also alternated (VAD, MP, CP) in an effort to prevent the development of multidrug resistance. Median survival of the two maintenance groups from randomization (36 months for group I and 31 months for group II, p = 0.3) as well as response duration (13 months in group I and 15 months in group II, p = 0.95) were similar. Toxicities were more pronounced both with VAD induction and in the combination maintenance arm. The addition of chemotherapy to the IFN maintenance regimen in MM did not have an advantage over IFN alone.

Hematopoietic stem cell transplants for multiple myeloma

Standard chemotherapy with melphalan-prednisone or a combination of alkylating agents has not extended the overall survival of patients with multiple myeloma during the last 30 years and strictly defined complete remissions (CR) are exceedingly rare. The early mortality with conventional therapy varies between 2 and 10 percent. A substantial increase in the dose of melphalan (100-140 mg/m2) has resulted in a 30-45% CR rate in newly diagnosed patients and an overall survival advantage of approximately 1 year. However, treatment related morbidity and mortality, due to prolonged cytopenia was unacceptably high. Based on these findings the dose intensity was further increased by either escalating melphalan to 200 mg/m2 or by adding total body irradiation, while at the same time providing stem cell support to shorten the duration of cytopenia. Autologous transplants, especially with peripheral blood stem cells and hematopoietic growth factors, can now be performed safely up to the age of 70 with a low transplant-related mortality (2-10%). A CR is attained in approximately 50% of previously untreated patients and 10-20% of refractory cases. Overall survival of newly diagnosed and refractory patients treated with autotransplants appears superior to that of patients receiving conventional chemotherapy. Therefore, autotransplantation should be considered as a treatment option in all patients with multiple myeloma at least up to the age of 65. Despite these encouraging findings, most myeloma patients ultimately relapse and the survival curves do not suggest that autotransplantation as currently performed is a curative approach in a substantial proportion of patients. Further improvement with autotransplants should be achieved by providing tumor-free grafts and by introducing post-transplantation manipulations, aimed at eradicating minimal residual disease.

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

Interferon (INF) has been incorporated as part of maintenance therapy after high dose treatment in order to make remissions more durable. In this study we have compared peripheral blood stem cell transplant (PBSCT) versus autologous bone marrow transplant (ABMT) with respect to INF tolerance. Thirty nine PBSCT patients have been compared to 37 ABMT patients for INF tolerance. This is followed by a comparison of 15 PBSCT patients versus 21 ABMT patients for engraftment details, response and survival. INF was started at a median of 61 days in the PBSCT and 58 days in the ABMT patients (P = NS). It was well tolerated in both groups without a significant difference in toxicity in the two arms. Engraftment was more rapid in the PBSCT patients with platelet recovery being significantly faster. Response and survival showed a favourable trend for ABMT patients though statistical significance was not reached and the cost of PBSCT was 12% cheaper. We were thus able to conclude that PBSCT grafts were as durable and could tolerate INF just as well as ABMT. Engraftment was more rapid and the procedure of PBSCT was also cheaper. Further studies with a larger group of patients will be required before comments on the efficacy of treatment can be made.

The role of chemotherapy in the treatment of multiple myeloma

Plasma cell neoplasms often present in an asymptomatic, stable phase. Treatment should not be started until manifestations, such as bone pain, increased susceptibility to infections, renal failure, anaemia and weight loss, announce that the disease has progressed to the MM phase. Conventional therapy with melphalan and prednisone results in objective improvement in about 50% of patients and improves median survival to about 32 months from the start of treatment. Induction therapy should be continued until the M-protein reaches a stable plateau that lasts for at least 4 months. Maintenance therapy with melphalan prolongs the duration of the initial response, but does not improve overall survival, in comparison with patients receiving no maintenance therapy, because survival following relapse is shortened in those receiving maintenance melphalan. In two randomized clinical trials, maintenance treatment with interferon alpha prolonged remissions durations and overall survival of MM patients who responded to induction chemotherapy. Second-line treatment for MM patients who are primary refractory to melphalan, and for those who respond initially and then relapse with refractory disease, is outlined. Although long-term control is possible for a minority of patients, it is unlikely that MM can be cured with currently available chemotherapeutic agents. We need to learn more about the basic biology of the disease.

Both early and committed haemopoietic progenitors are more frequent in peripheral blood than in bone marrow during mobilization induced by high-dose chemotherapy + G-CSF

Haemopoietic growth factor administration following high-dose chemotherapy markedly amplifies progenitor cell pool in the peripheral blood (PB). Collection and reinfusion of these cells enable rapid haemopoietic reconstitution following autograft. Less is known on engraftment potentiality of bone marrow (BM) cells taken under analogous conditions. To investigate this tissue, PB and BM were evaluated simultaneously during maximal mobilization in a series of 14 patients undergoing the HDS chemotherapy programme. A significantly higher growth of committed progenitors was found from PB rather than from BM (663 +/- 123 v 267 +/- 40 CFU-GM/10(5) MNC, respectively). Also, significantly more CFU-GM could be collected by a median of three leukaphereses, compared to those harvested from BM (158 +/- 31 v 16 +/- 4 x 10(4) CFU-GM/kg, respectively). Most mobilized CFU-GM were phenotypically immature (CD15-); in addition, circulating cells included primitive progenitors, as assessed by LTC-IC assay, or by evaluation of non-proliferating pre-CFU-GM, selected by an anti-CD71 immunotoxin. The amount of pre-CFU-GM determined by both techniques was consistently higher in PB than in BM. Moreover, a direct correlation could be established between circulating CFU-GM and primitive precursors. Thus, during optimally induced mobilization, PB contains many more haemopoietic progenitors, of both committed and primitive stages, than does BM. Under such conditions, PB is probably the best source of material for graft purposes.

Primary plasma cell leukaemia

Among 750 previously untreated patients with multiple myeloma, 27 (4%) presented with plasma cell leukaemia. All but one patient had high tumour mass and, when compared with comparable patients without leukaemia, more frequent extraosseous involvement, thrombocytopenia, high serum lactate dehydrogenase and hypodiploid plasma cells. Most patients also had complex cytogenetic abnormalities. Treatment with standard melphalan-prednisone was ineffective, with a median survival of 2 months, but more intensive chemotherapy induced responses in approximately one-half of the patients, with a median survival of 20 months. Primary plasma cell leukaemia usually results from the proliferation and extramedullary expansion of immature plasma cells and requires prompt and intensive chemotherapy.

Intensive chemotherapy with blood progenitor transplantation for primary resistant multiple myeloma

This study assessed the feasibility and effect of blood progenitors as the only source of haemopoietic support for myeloablative therapy for patients with primary resistant multiple myeloma and markedly infiltrated bone marrow. 17 patients with advanced, primary resistant myeloma received a priming regimen of cyclophosphamide (3 g/m2) and etoposide (900 mg/m2) with GM-CSF. During haematological recovery, at least 2 x 10(6) CD34+ mononuclear cells/kg were collected from each patient with 4-12 leukaphereses. High-dose chemotherapy was then given which consisted of thiotepa (750 mg/m2), busulfan (10 mg/kg) and cyclophosphamide (120 mg/kg) followed by reinfusion of the blood progenitors. Haemopoietic reconstitution was rapid with recovery of granulocytes to > 1.0 x 10(9)/l after a median of 10 d and of platelets to 50 x 10(9)/l after a median of 29 d. The myeloma responded in 10/17 patients for a projected median duration of at least 12 months. Survival was prolonged significantly in comparison with the outcome of control patients who did not receive intensive treatment. Blood progenitors, assessed from the number of CD34+ cells, produced early haemopoietic recovery after myeloablative therapy that induced sustained control of advanced and resistant multiple myeloma.

Multiple myeloma in the elderly

While multiple myeloma is an incurable disease for nearly all patients, current chemotherapy and supportive care can result in significant disease control and improved duration of survival and quality of life. With the average age of patients about 70, most of the high-dose curative strategies exclude the bulk of patients affected by the disease. Recent advances in understanding the biology and pathophysiology of myeloma have led to novel therapies aimed at altering drug resistance, improving duration of the plateau phase, interrupting the cytokine growth stimulation, and improving management of common complications including infections, anemia, and bone lesions. These latter approaches are not restricted to younger patients, and early evidence indicates that elderly patients are also likely to benefit.

Recent progress in multiple myeloma

Multiple myeloma is recognized as a neoplasm of phenotypically mature plasma cells which produces a variety of clinical symptoms related both to tumour infiltration of the bone marrow and cytokine production. The latter results in bone disease and a complex interactive network between plasma cells, marrow stromal cells and other hematopoietic cells. This serves to sustain the myeloma proliferative pool and promote maturation and secretion of monoclonal immunoglobulin. Whereas the recognizable tumour cells in myeloma are the most mature B cells, early lymphoid cells are involved in the disease and probably represent the proliferative pre-plasma cell compartment. The definition of the myeloma 'stem cell' remains controversial, but our understanding of early pre-plasma cell differentiation in multiple myeloma has been aided by studies on normal non-neoplastic equivalents. Techniques like high resolution flow cytometry, flow cytometric DNA analysis and improvements in our ability to obtain karyotypic data in multiple myeloma will improve our understanding of myeloma cell biology, hopefully yielding new prognostic information. Finally, improvements in assessing prognosis will help identify patients whose survival with standard therapy is limited and who may require innovative or aggressive treatment protocols. These individuals must be separated from patients who either require no initial therapy or who are likely to have good outcomes with standard approaches.

Multiple myeloma

Multiple myeloma occurs in over 2000 new patients in England and Wales each year. It presents most frequently as bone pain and patients tend to become dehydrated and may develop renal failure. No available treatment is curative, but about two thirds of patients achieve a stable response with low dose combination chemotherapy. Combination chemotherapy including doxorubicin and carmustine with the alkylating agents cyclophosphamide and melphalan achieve a higher stable response rate than conventional treatment with melphalan and prednisone without additional haematological toxicity. These responses are associated with loss of bone pain and patients remain symptom free for months without further treatment. Relapse occurs on average in a little under two years and, though second responses are frequently obtained, the disease eventually becomes refractory. This paper looks at who should be treated and the benefits that may be expected from the treatments available.

Hematopoietic stem cell autografts in support of myeloablative therapy for multiple myeloma

This paper reports the experience of a single investigator team on the use of autografting in support of myeloablative therapy for multiple myeloma. This demonstrates continued progress toward decreased morbidity, and virtual elimination of mortality, as a result of rapid hematopoietic recovery, due to the use of peripheral blood stem cell grafts in newly diagnosed patients receiving several non-cross-resistant induction regimens followed by two autologous transplants, complete remission rates in excess of 50% can be achieved. Prognostic factors have also been identified for event-free and overall survival.

Multiple myeloma treated with mitoxantrone in combination with vincristine and prednisolone (NOP regimen) versus melphalan and prednisolone: a phase III study. Nordic Myeloma Study Group (NMSG)

One-hundred-and-fifty-one patients with previously untreated multiple myeloma were allocated to treatment with either NOP regimen (mitoxantrone 16 mg/m2 and vincristine 2 mg day 1 and prednisolone 250 mg day 1-4 and 17-20) or M+P regimen (melphalan 0.25 mg/kg and prednisolone 100-200 mg/day day 1-4). Both regimens were repeated every 4 weeks and were scheduled for 1 year. Seventy-seven patients were treated with NOP and 74 patients with M+P. No major clinical differences were recorded between the groups before treatment. Sixty percent of the patients responded (CR+PR) to NOP versus 64% to M+P (NS). The time to progression was 16 months (95% C.L. 14-51) in the NOP group versus 21 months (95% C.L. 15-27) in the M+P group (NS). The median survival was 14 months (7-21) in the NOP group and 31 months (21-43) in the M+P group (p = 0.02). NOP was significantly more toxic than M+P. Seven patients treated with NOP died due to infection and neutropenia and 1 patient died of cardiac toxicity, in contrast to 1 death due to infection and neutropenia in the M+P group. Gastrointestinal toxicity was acceptable in both groups. In conclusion, NOP was inferior to M+P as primary treatment of multiple myeloma.

Recombinant human erythropoietin and the anemia of multiple myeloma

The anemia of multiple myeloma (MM) is multifactorial, including physical replacement of normal hemopoiesis by tumor cells, renal failure and cytokines which contribute to the blunted erythropoietin (EPO) response observed in anemias of chronic disease. Recombinant EPO has been evaluated in anemic patients with stable multiple myeloma (< or = 10g% hemoglobin). Responses (> or = 2g% hemoglobin increase) were observed in 78% of 41 patients in two separate studies. Responses were associated with an increase in bone marrow erythropoietic cell compartment and reticulocytosis. Evaluation of potential parameters affecting response identified prolonged cytotoxic therapy for > 12 months, especially with alkylating agents and pre-treatment EPO levels > 100 U/L, both of which seemed to decrease the likelihood of EPO response. EPO is a safe and effective treatment for the anemia associated with MM.

Risk of disease progression in asymptomatic multiple myeloma

PURPOSE

In recent years, increasing numbers of patients with asymptomatic multiple myeloma have been diagnosed by chance and followed without any therapy. Those at risk for early or late disease progression should be distinguished in order to prevent complications. This study defined prognostic factors that would predict the need for early treatment.

PATIENTS AND METHODS

We followed 95 patients with asymptomatic multiple myeloma without chemotherapy between 1974 and 1991. Magnetic resonance imaging (MRI) of the spine was conducted in 23% of patients with normal radiographs. An increase in serum myeloma protein to more than 50 g/L or new lytic bone lesions justified the institution of chemotherapy. Response to treatment and survival were assessed, and prognostic factors were defined for early or late disease progression by standard techniques.

RESULTS

The median time to progression in all patients was 26 months. The 25 patients with either a lytic bone lesion, or both serum peak greater than 30 g/L and Bence Jones proteinuria, had the shortest median time to progression of 10 months; the 27 patients without any harmful factor remained stable for a median of 61 months. MRI confirmed bone or marrow disease in half of the patients with normal radiographs and may assist in the prognostic staging. Despite the markedly different times of disease stability, the response rates and survival after chemotherapy were similar for all groups of patients.

CONCLUSION

Among asymptomatic patients with multiple myeloma, the extent of disease at diagnosis and the subsequent rate of disease evolution were major factors in the total survival time. These patients are a markedly heterogeneous group who may benefit from different approaches to treatment according to defined risk factors.

Modified adriamycin-vincristine-dexamethasone (m-VAD) in primary refractory and relapsed plasma cell myeloma: an NCI (Canada) pilot study. The National Cancer Institute of Canada Clinical Trials Group

The purpose of this single arm phase II study was to test a modified version of the three drug combination vincristine, adriamycin and dexamethasone (m-VAD), in which intravenous vincristine (0.4 mg/d) and adriamycin (9 mg/m2 per day) infusions are administered for only 2 h on days 1-4 of each 28 d cycle, in patients with refractory multiple myeloma. In addition, only two 4 d courses of dexamethasone 40 mg/d was given during each cycle. The entry criteria for 44 patients included plasma cell myeloma and a measurable monoclonal peak, either refractory to initial treatment with melphalan and prednisone, or resistant to melphalan and prednisone after initially responding (resistant relapsed disease, 27 patients). Patients treated previously with chemotherapy other than melphalan and prednisone were excluded. There were no complete responses. Of the 41 evaluable patients who completed at least one course of therapy 11 had a partial response (27%, 95% C.I. 14-40%). The response rates were 19% for primary refractory disease patients, and 32% for those with resistant relapsed disease. The median duration of response was 4 months. The median survival for all 44 patients was 7.6 months (5.5 months for primary refractory patients, and 10 months for relapsed resistant disease patients). Episodes of documented bacterial infection occurred in 12 patients, and 10 patients had minor viral infection. The dexamethasone dose was reduced in 12 patients. The median neutrophil nadir was 1.2 x 10(9)/l, and median platelet nadir was 147 x 10(9)/l. Five deaths were judged as treatment related and occurred during marrow cytopenia. The results of this modified form of VAD are inferior to that reported previously for 4 d continuous infusions of vincristine and doxorubicin. This could be related to either patient selection factors, or to a reduction of the efficacy of the drug combination produced by either the shortened intravenous infusions and/or omission of one 4 d course of dexamethasone.

Modulation of multidrug-resistant multiple myeloma by cyclosporin. The Leukaemia Group of the EORTC and the HOVON

Resistance to chemotherapy in refractory multiple myeloma is frequently associated with expression of multidrug resistance (MDR). In resistant cells, intracellular accumulation of doxorubicin and vincristine does not occur because the MDR-1 gene product, a membrane glycoprotein (PgP), is an energy-dependent efflux pump. Cyclosporin is one of several non-cytotoxic drugs that can block the function of PgP. In a prospective study, we assessed the possibility that cyclosporin could be used clinically to modulate MDR. We studied 21 patients with multiple myeloma; disease had progressed during primary chemotherapy in 6 and was resistant to VAD (vincristine, doxorubicin, dexamethasone) in 15. The patients received cyclosporin by continuous infusion during VAD treatment; there were three cyclosporin dosage groups (5, 7.5, 10 mg/kg daily). Serum cyclosporin concentrations adequate for MDR modulation were reached in all patients receiving 7.5 or 10 mg/kg daily. 47% (7) of the VAD-refractory patients and 48% (10) of the whole group responded to VAD. Before treatment, MDR-1 expression was present in 12 patients. After VAD plus cyclosporin, no MDR-1-positive plasma cells were present in 6 of 8 patients tested. The response rate in MDR-1-positive patients was 58% compared with 33% in all our patients. Toxic effects were mild and reversible and did not include nephrotoxic or serious cardiovascular side-effects. 12 months after the start of treatment, survival was 85%, and disease-free survival at a median of 9 months after the response was 65%. Thus, in multiple myeloma clinical resistance to VAD can be circumvented by cyclosporin, which enables the cytotoxic drugs to eliminate resistant myeloma cells.

Les traitements du myélome multiple en 1992

In 1992, the Melphalan-Prednisone (M. P.) protocol remains a standard treatment of multiple myeloma even if a lot of new ways have been investigated during the last years. Polychemotherapies may appear better than M.P. for high tumor mass myeloma. Interferon is useful as maintenance treatment after chemotherapy. Combinations of interferon and chemotherapy, during the induction phase, are under evaluation. Because of their toxicity, heavier treatments, with stem cells reinfusion, are being developed mainly with younger patients. Thanks to these approaches the response's rate is increasing but any improvement of survival is still to be demonstrated. Other recent investigations have concerned diphosphonates and immunoregulators. Larger use of these new treatments requires more informations about prognostic factors and their integration in therapeutic strategy of myeloma.