Oligoclonal protein bands and Ig isotype switching in multiple myeloma treated with high-dose therapy and hematopoietic cell transplantation

Multiple myeloma (MM) is usually characterized by production of a single serum monoclonal protein of constant isotype and light-chain restriction. Multiple Ig isotypes and isotype switches, which are rare in untreated patients, are reported to be more common in patients undergoing myeloablative therapy. These additional protein bands, detected by immunofixation electrophoresis (IFE), could be due to altered paraprotein production by the malignant plasma cell clone or oligoclonal Ig production during recovery of B-cell function after myeloablative therapy. We analyzed abnormal protein bands (APB), distinct from the presenting paraprotein, in 550 patients receiving high-dose therapy with autologous hematopoietic cell transplantation at a single institution. Fifty-five patients (10%) had APB, 48 had oligoclonal bands (OB), and 23 had an apparent isotype switch (IS) on IFE (16 had both OB and IS). Morphologic and flow cytometric examination of bone marrow in 17 patients with IS showed no evidence of a clonal plasma cell isotype switch. Patients with APB had significantly higher complete response to therapy (67% v 37%, P = .001). To assess the independent prognostic relevance of APB, a multivariate analysis was performed among 471 patients surviving at least 12 months from first transplant (all patients developing APB had done so by 12 months from first transplant). APB (in 50 patients) was a favorable feature for both event-free (rank 3, P = .004) and overall survival (rank 3, P = .0005). We propose that OB and IS are likely to be due to recovery of Ig production rather than alterations in the biology of the malignant plasma cell clone.

Salvage autologous or allogeneic transplantation for multiple myeloma refractory to or relapsing after a first-line autograft?

Forty-two patients allografted for multiple myeloma after not having attained at least a partial remission (n = 19) or after having experienced disease progression (n = 23) following one autograft were compared with 42 pair-matched controls who underwent salvage autotransplantation under identical conditions. Autografted controls were matched closely for albumin, C-reactive protein, creatinine, disease sensitivity, duration of standard therapy prior to the first transplant, Ig isotype, karyotype, LDH, and response to the first transplant, but, in comparison to allografted patients, were older, had higher beta2-microglobulin, and had a shorter interval between the two transplants. The complete remission rate was 41% after allogeneic and 33% after autologous transplantation (P = NS). The 3-year probability of event-free survival was comparable for the two groups (25 +/- 8% after autografting and 20 +/- 8% after allografting). The 3-year probability of survival was significantly higher after autologous transplantation (54 +/- 8% vs 29 +/- 9%; P = 0.01). Twenty-one patients in the autograft group were alive 11-59 months (median 32) following the second transplant, while 15 patients in the allograft group were alive at 10-53 months (median 20). The 3-year probability of disease progression was significantly lower after allogeneic transplantation (31 +/- 10% vs 72 +/- 9%, P = 0.03). The 1-year probability of transplant-related mortality was significantly higher after allografting (43 +/- 8% vs 10 +/- 5%; P = 0.0001). We conclude that while autografting appears to be superior to allografting for salvage therapy of myeloma persisting or relapsing after one previous autotransplant in terms of overall survival, event-free survival is comparable due to significantly lower disease progression after allografting. Reduction in allograft-related toxicity can potentially improve the results of allogeneic transplantation significantly.

Syndecan-1 is a multifunctional regulator of myeloma pathobiology: control of tumor cell survival, growth, and bone cell differentiation

Multiple myeloma is characterized by an accumulation of malignant plasma cells in the bone marrow coupled with an altered balance of osteoclasts and osteoblasts, leading to lytic bone disease. Although some of the cytokines driving this process have been characterized, little is known about the negative regulators. We show that syndecan-1 (CD 138), a heparan sulfate proteoglycan, expressed on and actively shed from the surface of most myeloma cells, induces apoptosis and inhibits the growth of myeloma tumor cells and also mediates decreased osteoclast and increased osteoblast differentiation. The addition of intact purified syndecan-1 ectodomain (1 to 6 nmol/L) to myeloma cell lines in culture leads to induction of apoptosis and dose-dependent growth inhibition, with concurrent downregulation of cyclin D1. The addition of purified syndecan-1 in picomolar concentrations to bone marrow cells in culture leads to a dose-dependent decrease in osteoclastogenesis and a smaller increase in osteoblastogenesis. In contrast to the effect on myeloma cells, the effect of syndecan-1 on osteoclastogenesis only requires the syndecan-1 heparan sulfate chains and not the intact ectodomain, suggesting that syndecan's effect on myeloma and bone cells occurs through different mechanisms. When injected in severe combined immune deficient (scid) mice, control-transfected myeloma cells (ARH-77 cells) expressing little syndecan-1 readily form tumors, leading to hind limb paralysis and lytic bone disease. However, after the injection of syndecan-1-transfected ARH-77 cells, the development of disease-related morbidity and lytic bone disease is significantly inhibited. Taken together, our data demonstrate, both in vitro and in vivo, that syndecan-1 has a significant beneficial effect on the behavior of both myeloma and bone cells and therefore may represent one of the central molecules in the regulation of myeloma pathobiology.

Comparable engraftment kinetics following peripheral-blood stem-cell infusion mobilized with granulocyte colony-stimulating factor with or without cyclophosphamide in multiple myeloma

PURPOSE

To compare, in the setting of tandem autotransplantations for multiple myeloma (MM), two established methods of peripheral-blood stem-cell (PBSC) procurement with chemotherapy or hematopoietic growth factor alone.

PATIENTS AND METHODS

Between June 1994 and July 1995, 44 patients with MM were randomized to PBSC mobilization with either granulocyte colony-stimulating factor (G-CSF) 16 microg/kg (group 1; n = 22) or high-dose cyclophosphamide (HDCTX) 6 g/m2 plus G-CSF 5 microg/kg (group 2; n = 22). All 44 patients received melphalan 200 mg/m2 with their first autograft and 32 patients proceeded to a second transplantation.

RESULTS

Group 2 required a significantly longer time interval for completion of PBSC collection than group 1 (median, 22 v 8 days; P = .0001), greater frequency of hospitalization (100% v 32%; P = .0001), and increased transfusion of platelets (86% v 18%; P = .0001) and packed RBCs (86% v 55%; P = .02). Likewise, the incidence of fever and pneumonia/sepsis were higher in group 2 (P = .02 and P = .04, respectively). Surprisingly, despite greater CD34 cell quantities infused in group 2, median recovery times of granulocytes (both > 500/microL and 2,500/microL) and platelets (both > 50,000/microL and > 100,000/microL) were similar (all P > .7). Posttransplant toxicities were also similar.

CONCLUSION

Compared with HDCTX plus G-CSF, high-dose G-CSF alone is associated with lower morbidity, shorter duration of PBSC mobilization, and comparable hematopoietic recovery after transplantation, which should result in significant cost reduction. Considering the relatively limited antitumor activity of HDCTX (10% with > or = 50% tumor cytoreduction), PBSC mobilization with HDCTX should be limited to selected patients with persistent MM despite induction chemotherapy.

Jumping translocations of chromosome 1q in multiple myeloma: evidence for a mechanism involving decondensation of pericentromeric heterochromatin

Karyotypes in multiple myeloma (MM) are complex and exhibit numerous structural and numerical aberrations. The largest subset of structural chromosome anomalies in clinical specimens and cell lines involves aberrations of chromosome 1. Unbalanced translocations and duplications involving all or part of the whole long arm of chromosome 1 presumably occur as secondary aberrations and are associated with tumor progression and advanced disease. Unfortunately, cytogenetic evidence is scarce as to how these unstable whole-arm rearrangements may take place. We report nonrandom, unbalanced whole-arm translocations of 1q in the cytogenetic evolution of patients with aggressive MM. Whole-arm or "jumping translocations" of 1q were found in 36 of 158 successive patients with abnormal karyotypes. Recurring whole-arm translocations of 1q involved chromosomes 5,8,12,14,15,16,17,19,21, and 22. A newly delineated breakpoint present in three patients involved a whole-arm translocation of 1q to band 5q15. Three recurrent translocations of 1q10 to the short arms of different acrocentric chromosomes have also been identified, including three patients with der(15)t(1;15)(q10;p10) and two patients each with der(21)t(1;21)(q10;p13) and der(22)t(1;22) (q10;p10). Whole-arm translocations of 1q10 to telomeric regions of nonacrocentric chromosomes included der(12)t(1;12) (q10;q24.3) and der(19)t(1;19)(q10;q13.4) in three and two patients, respectively. Recurrent whole-arm translocations of 1q to centromeric regions included der(16)t(1;16)(q10;q10) and der(19)t(1;19)(q10;p10). The mechanisms involved in the 1q instability in MM may be associated with highly decondensed pericentromeric heterochromatin, which may permit recombination and formation of unstable translocations of chromosome 1q. The clonal evolution of cells with extra copies of 1q suggests that this aberration directly or indirectly provides a proliferative advantage.

Collection of more hematopoietic progenitor cells with large volume leukapheresis in patients with multiple myeloma

Reinfusion of mobilized peripheral blood stem cells (PBSC) after high dose chemotherapy accelerates hematopoietic recovery. Because of the relatively low content of hematopoietic progenitors in the peripheral blood even after mobilization, multiple leukapheresis procedures are necessary to reach the required target number of CD34 cells to ensure prompt engraftment post-transplantation. Our previous studies have shown that the highest proportions of hematopoietic progenitors cells (CD34) are collected during the first three days of apheresis, whereas peak levels of myeloma cells are observed during subsequent days. Therefore, large volume leukapheresis (LVL), defined as processing of greater than 3 blood volumes or a total of at least 15 liters, was explored in 23 myeloma patients, undergoing 91 procedures; 14 patients were mobilized with high dose cyclophosphamide (6g/m2) and hematopoietic growth factors and 9 with G-CSF only. CD34 yields were measured separately for the first and last two hours of collection. We observed no decrease in CD34 cells/kg during the last two hours of collection and when the LVL collections were compared to historical matched controls, mobilized with the same regimen, the median quantity of CD34 cells/kg/liter collected remained equivalent during all days of apheresis. When compared to G-CSF only, mobilization with high dose cyclophosphamide appeared to result in superior hematopoietic stem cell collections. Interestingly, the G-CSF group experienced a progressive decrease in platelets during consecutive days of LVL, while the opposite was seen in the cyclophosphamide group. LVL procedures were not associated with a higher complication rate than standard volume apheresis. We conclude that LVL procedures allow collection of more CD34 cell per session while not jeopardizing progenitor cell collections during subsequent sessions. Since more CD34 cells are collected, fewer days are required to attain the optimal target of progenitor cells. This should result in PBSC grafts with less tumor contamination.

Advances in therapy of multiple myeloma: lessons from acute leukemia

This paper traces the lack of progress, until recently, in the treatment of multiple myeloma (MM) to having ignored the principles that led to cure in acute leukemia more than 2 decades ago. Only in the mid-1980s did investigation begin to consider complete remission (CR) a research objective, representing a necessary first step toward cure. The experience with autologous and allogeneic stem cell-supported high-dose therapy is reviewed, demonstrating, in both historically controlled and randomized studies, the validity of the dose-response concept in MM in terms of increased CR rates as well as extended event-free (EFS) and overall survival (OS). Avoidance of hematopoietic stem cell-damaging agents, especially melphalan, nitrosoureas, and ionizing radiation to marrow-containing sites, assures the ability of peripheral stem cell collection of high quality and quantity, providing rapid engraftment so that mortality is well under 5% following high-dose melphalan (200 mg/m2). This treatment can be applied safely to patients even >70 years of age and in the presence of renal failure. Tandem autotransplants after multiregimen induction have yielded CR rates in the 40% range with median durations of EFS and OS of 43 and 62 months, respectively. Certain chromosomal abnormalities (11 and 13; and translocations) represent the dominant adverse prognosticator for EFS and OS, confirmed in over 500 patients including those with prior therapy. Allogeneic transplants, possible in less than 10% of MM patients, are associated with a 50% mortality during the first year and, unfortunately, late relapses; thus, this approach should be reserved for patients with high-risk disease early in their management. A risk-based treatment algorithm that matches a patient's disease risk with the risk of intervention is presently used, followed by bisphosphonate therapy, not only to delay the onset of MM-related bone disease but also to induce tumor cell apoptosis, indirectly or directly, by down-regulation of cytokines with antiapoptotic activities. Although many patients relapse, this author subscribes to his mentor's motto: "Be Prepared for Success!".

Elevated levels of shed syndecan-1 correlate with tumour mass and decreased matrix metalloproteinase-9 activity in the serum of patients with multiple myeloma

Sera from 20 myeloma patients and 12 normal controls were analysed for the presence of syndecan-1 and matrix metalloproteinase-9 (MMP-9). The level of syndecan-1 in the serum was elevated in 7/20 (3 5%) myeloma patients whilst 6/19 patients (31%) had decreased serum MMP-9 activity. The presence of increased syndecan-1 was associated with decreased serum MMP-9. Both elevated syndecan-1 and decreased MMP-9 were associated with higher marrow plasmacytosis, serum beta-2 microglobulin and paraprotein levels. These data provide evidence that the syndecan-1 ectodomain is shed in vivo. Quantitation of serum syndecan-1 may be a useful measure of tumour mass and may have important implications for myeloma biology.

Incidence and impact of light chain associated (AL) amyloidosis on the prognosis of patients with multiple myeloma treated with autologous transplantation

Little is known about the incidence of clinically occult AL amyloid in patients with multiple myeloma and its impact on prognosis of these patients. To address these issues, subcutaneous fat pad aspirates (SAFA) and bone marrow biopsies were evaluated for the presence of amyloid in a cohort of newly diagnosed patients with multiple myeloma prior to enrollment on a phase II study including tandem transplants. Organ directed biopsies were performed when clinically indicated. Presence of amyloid at > or = 1 site was noted in 32 patients (38%). SAFA was positive in 25 (31%), bone marrow in 8 patients (10%) and other organ sites in 7 patients. Patients with and without amyloid did not differ in disease characteristics, in particular no lambda predominance was observed in patients with amyloid. Event free survival (59+ vs 52 months; p = .9) and overall survival (59+ vs 66+ months; p = .9) were similar in both groups. Even the seven patients with symptomatic organ involvement with AL amyloid had a median overall survival of 38+ months. In conclusion, AL amyloidosis occurs more often than previously reported, but its presence does not influence the outcome of these patients after transplantation.

Treatment of AL-amyloidosis with dexamethasone plus alpha interferon

Current therapy for primary systemic (AL) amyloidosis has only modest efficacy (response rate 25%) and because it includes alkylating agents, it has a significant leukemogenic potential (actuarial risk 21% at 3.5 years). We treated 9 consecutive patients with biopsy proven AL amyloidosis seen at our institution with pulse dexamethasone induction (40 mg on days 1-4, 9-12, 17-20 repeated q 35 days) for 3-6 cycles followed by maintenance alpha interferon 3-6 million units thrice weekly. Three patients also received maintenance dexamethasone (40 mg/day x 4 days q 4-8 weeks) for the first year. Improvement in > or = 1 AL organ involvement was seen in 8 of 9 patients. Of 7 patients with nephrotic range proteinuria, 6 had > or = 50% reduction in nonspecific proteinuria with a median time to response of 4 months (range 3-9 months). Marked improvement in organ function was also seen in 4 patients with gastrointestinal, hepatic and neuropathic involvement. However, none of the 2 patients with congestive heart failure improved. This dexamethasone plus alpha interferon regimen, devoid of leukemogenic potential, may lead to rapid and durable improvement in organ function in a significant proportion of patients with AL amyloidosis and deserves further evaluation as front line therapy.

Feasibility and cost-effectiveness of outpatient autotransplants in multiple myeloma

This report summarizes 2 years experience in performing 336 autotransplant procedures in 251 consecutive patients with multiple myeloma, using high-dose melphalan at 200 mg/m2 in the context of a tandem transplant program. A total of 91 patients received 118 transplants as outpatients while the remaining 160 patients received 218 transplants as inpatients. Outpatients were more often younger, with better stem cell products, normal serum albumin and beta-2-microglobulin levels as well as chemotherapy-sensitive disease compared to inpatients. There were no differences in hematopoietic recovery and non-hematologic toxicities between outpatient and inpatient transplant recipients. Post-transplant febrile neutropenia and most other post-transplant toxicities were managed successfully in an ambulatory setting. Although liberal criteria were developed for hospitalization of outpatients, including clinical parameters as well as patient desire and physician/nurse judgement, only 21% of outpatients required admission after transplantation. Median hospital stay for these outpatients was 9 days, while inpatients were hospitalized for a median of 15 days (P = 0.0001). After adjusting for differences in disease and host features, our study showed outpatient management resulted in significant financial savings due to lower pharmacy (42%), hospitalization (50%) and pathology/laboratory charges (36%). We conclude that outpatient transplants should facilitate access to myeloablative therapy, thereby improving complete remission rates and survival of myeloma patients.

Advances in the treatment of multiple myeloma

Conventional chemotherapy for multiple myeloma results in low complete response rates, and disease progression usually occurs within a couple of years. High-dose chemotherapy with autotransplantation, which has been shown to result in encouraging complete remission rates over several years in phase II studies, was recently shown in a randomized study to be superior to conventional therapy. Eventual tumor recurrence is a problem after autografting, and the development of novel maintenance chemotherapy or immunotherapy strategies is necessary to eliminate minimal residual disease. Although allogeneic transplantation cures a small proportion of patients, high transplant-related mortality and relapse rates hamper survival. Development of novel conditioning regimens and means to harness the graft-versus-myeloma effect without the associated morbidity of graft-versus-host disease are necessary to improve success rates. Supportive therapy, mainly bisphosphonates to delay progression of bone disease and improve bone density and erythropoietin to improve hemoglobin levels, also plays an important role in the overall management. This article reviews therapeutic advances in multiple myeloma from the 1996 literature.

High-dose chemotherapy with carboplatin, cyclophosphamide and etoposide and autologous transplantation for multiple myeloma relapsing after a previous transplant

Eighteen extensively pre-treated patients (35-73 years, median 46) with relapsed multiple myeloma received salvage chemotherapy with 6 g/m2 cyclophosphamide, 800 mg/m2 carboplatin, and 1800 mg/m2 etoposide (CCV) as a 96-h continuous infusion followed by autologous peripheral blood stem cells. The median number of prior chemotherapy regimens was five (range 4-10), including at least one autograft. Four patients died of toxicity, and one developed dialysis-dependent renal failure, while the others tolerated CCV well. Three of six patients with pre-transplant creatinine of > 1 mg/dl died of toxicity compared with one of 12 with creatinine < or = 1 mg/dl (P = 0.083, Fisher's exact test). Three of four patients treated with four previous regimens showed > 50% reduction in tumor compared with one of 14 treated with > 4 regimens (P = 0.02, Fisher's exact test). At the last follow-up, five patients were alive at 8-24 months (median 13) with stable (n = 1) or progressive (n = 4) disease, and nine had died of progressive disease at 2.5-15 months (median 7). We conclude that CCV chemotherapy with autografting is tolerated well by extensively pre-treated myeloma patients provided the pre-transplant creatinine is normal, but toxicity in patients with abnormal renal function is high. The efficacy in multiply relapsed disease is poor, with response in only 22% of patients. CCV may deserve further evaluation early in the course of myeloma in patients with normal renal function.

Peripheral stem cell mobilization and engraftment in patients over age 60

Data from 225 multiple myeloma (MM) patients, undergoing peripheral stem cell (PBSC) mobilization with high-dose cyclophosphamide and hematopoietic growth factors, were analyzed for median CD34+ cell count and median time to post-transplant neutrophil (ANC > 500/microliters) and platelet (> 50,000/microliters) recovery according to age groups (20-49, 50-59 and > or = 60 years) and duration of prior therapy (< or = 12, 13-24, or > 24 months). Fifty-seven of the 225 patients were > or = 60 years. No difference in either the median number of CD34+ cells collected or time to engraftment occurred between age groups, when adjusted for duration of prior therapy. These data support the concept that autotransplants can be performed safely in patients > or = 60 years and that these patients should not be excluded from the most effective treatment modalities.

Unique role of cytogenetics in the prognosis of patients with myeloma receiving high-dose therapy and autotransplants

PURPOSE

Although important predictors of survival in myeloma patients have been identified, it is well recognized that better prognostic factors for this disease are needed. Because cytogenetics play a dominant role in the outcome of patients with acute leukemia, their prognostic value was evaluated in a large group of newly diagnosed and previously treated myeloma patients receiving autotransplants.

METHODS

A total of 427 either newly diagnosed (26%) or previously treated patients (74%) received tandem transplants, supported by mobilized peripheral-blood stem cells. Numerous variables, including cytogenetics, were analyzed for their impact on complete remission, event-free survival (EFS), and overall survival (OS).

RESULTS

Abnormal karyotypes were detected in 37% of our patients and were very complex, irrespective of the duration of standard therapy before the first autotransplant. In addition to previously recognized unfavorable implications of partial or complete deletion of chromosome 13 and 11q abnormalities, we now observed that the presence of any translocation likewise portended poor outcome (unfavorable karyotypes). On multivariate analysis, the absence of an unfavorable karyotype was the most favorable variable for both EFS (P = .0001) and OS (P = .0001). Other favorable factors were duration of standard therapy and a low beta-2 microglobulin (B2M) level before the first autotransplant. A risk-based classification system was developed according to the number of these favorable variables present, showing highly significant differences in event-free and overall survival.

CONCLUSION

Cytogenetics play a dominant role in myeloma and were independent of previously recognized important prognostic factors, such as B2M and duration of prior standard therapy.

Autotransplants in multiple myeloma: pushing the envelope

Substantial progress has been made in understanding the role of autotransplants in multiple myeloma. High dose therapy consistently induces a higher remission rate, longer remission duration, and overall survival. This article summarizes the results of several major studies to illustrate the above conclusions. Feasibility of autotransplants in patients with renal failure, utility of stem cell selection, and prognostic factors are also discussed. Autotransplants should be part of the overall treatment strategy for newly diagnosed myeloma patients under 70 years of age.

Thymidine kinase (TK) gene-transduced human lymphocytes can be highly purified, remain fully functional, and are killed efficiently with ganciclovir

A graft-versus-leukemia (GVL) effect has been considered a major factor responsible for cures in patients with hematologic malignancies undergoing allogeneic bone marrow transplantation; however, associated graft-versus-host disease (GVHD) results in significant morbidity and mortality. T-cell depletion reduces the incidence and severity of GVHD but eliminates, at least partially, the GVL effect. Reinfusion of donor T lymphocytes at relapse posttransplantation can induce a potent antitumor response, but GVHD still occurs in the majority of patients. Prior transduction of T lymphocytes with the suicide gene, the viral thymidine kinase (TK), permits specific cell kill on administration of ganciclovir (GCV). Therefore, infusion of TK-transduced T lymphocytes may induce GVL effect and allow for their subsequent selective elimination in case GVHD develops. To evaluate the efficacy and feasibility of this promising approach, anti-CD3-stimulated primary human lymphocytes cultured in interleukin-2 were TK-transduced by a retroviral vector carrying both TK and neomycin-resistance genes. After selection in G418, more than 90% of the cells contained the TK gene as shown by a semiquantitative polymerase chain reaction. In addition, 1 to 5 days of GCV exposure, at clinically achievable concentrations of 20 to 50 micromol/L, induced > or = 90% killing of G418-selected cells without affecting nontransduced cells. Correlation of the extent of T-cell kill and the proportion of TK-gene-transduced cells is consistent with the absence of a bystander effect. Transduced cells were CD3+ and either CD8+ or CD4+ and retained functional properties of untransduced cells. In vivo administration of GCV prevented tumor development after subcutaneous injection of TK-transduced murine myeloma cells (MOPC-11), whereas such an effect was not observed on injection of untransduced cells into the opposite flank. Our studies provide critical information that (1) adequate numbers of TK-transduced lymphocytes can be selected efficiently with > or = 90% purity, (2) selected cells remain functional, (3) 24 hours of exposure to GCV at clinically achievable concentration effects > or = 90% killing of selected cells, and (4) GCV is effective in vivo in killing TK-transduced cells. Based on these data, a clinical study has been initiated in patients with multiple myeloma with persistent or relapsing disease after T-cell-depleted allogeneic transplants.

Superiority of tandem autologous transplantation over standard therapy for previously untreated multiple myeloma

Virtually no progress has been made during more than 2 decades of clinical trials for multiple myeloma (MM) involving standard therapy (ST). Recent studies suggest that dose intensification requiring hematopoietic stem cell support results in higher complete response (CR) rates and extended disease control. "Total Therapy" (TT) consisting of noncross-resistant induction regimens, followed by a double autotransplant (AT) procedure, was administered to 123 untreated patients with symptomatic MM. Upon hematologic recovery, interferon (IFN) maintenance (3 million units [MU]/m2 subcutaneously thrice weekly) was given until disease recurrence/progression. Results were compared with the outcome of untreated patients receiving ST according to Southwest Oncology Group (SWOG) trials. One hundred sixteen pair mates were selected from both TT and among 1,123 patients to match for the major prognostic features. TT induced CR in 40% of all 123 patients (intent-to-treat). By 12 months, 7% had died, including 4% from treatment-related complications. With a median follow-up of 31 months, median durations of event-free survival (EFS) and overall survival (OS) are 49 and 62+ months, respectively. Abnormalities of chromosomes 11q and 13 were associated with inferior outcome, whereas CR within 6 months after induction was a favorable prognostic feature for both EFS and OS. In comparison to ST, TT induced higher PR rates (85% v 52%, P < .0001) (CR rates not available on SWOG trials) and extended EFS (49 v 22 months, P = .0001) and OS (62+ v 48 months, P = .01). Compared to ST, dose intensification with double AT markedly augments tumor cytoreduction, effecting not only higher CR rates but also significantly extending EFS and OS in previously untreated patients with MM.

Biology and therapy of multiple myeloma in 1996

Since the introduction of melphalan-prednisone for the treatment of multiple myeloma (MM) three decades ago, the prognosis of patients has not been improved by the addition of other agents, probably due to marked resistance of tumor cells, even at diagnosis, to commonly employed cytotoxic drugs. The biological basis for drug resistance is reviewed and current methods of diagnosis and staging delineated. The overview on treatment focuses on recurrent advances with myeloablative therapy demonstrating, in randomized and historically controlled trials, that high-dose therapy increases the incidence of true complete remission (CR) from 5% to approximately 40%, with an extension of median event-free (EFS) and overall (OS) survival durations to 3.5 and > or = 5 years, respectively. It is concluded that high-dose therapy should be offered to all patients with symptomatic meyloma, and current therapeutic research explores posttransplant immunotherapy.

Preceding standard therapy is the likely cause of MDS after autotransplants for multiple myeloma

Myelodysplastic syndromes (MDS) and acute myeloid leukaemia (AML) have been reported after autologous transplantation (AT) for lymphoma. It is not clear whether myeloablative therapy used in conjunction with autologous transplantation contributes to the development of MDS/AML or whether the conventional chemotherapy preceding the transplant, and administered over a prolonged period, causes these secondary malignancies. To address this issue, we examined 188 patients with multiple myeloma (MM) who had received AT. 71 patients with no more than one cycle of standard chemotherapy were enrolled in our Total Therapy program, designed to avoid exposure to alkylating agents prior to peripheral blood stem cell mobilization (group 1). The median duration of pretransplant therapy in group 1 was 7.6 months and significantly shorter than the 24 months of 117 patients (group 2) with more prolonged conventional therapy (P = 0.0001). All seven patients developing MDS post-transplantation belonged to group 2 (P = 0.02); the median durations from initial therapy and first transplant were 66 months (range 38-86) and 24 months (range 9-39), respectively. Our findings provide evidence that prolonged standard-dose alkylating agent therapy prior to transplantation, rather than autotransplant-supported myeloablative treatment, is associated with development of MDS/AML. Stem cell damaging alkylator treatment should be avoided, not to compromise PBSC collection, but also to reduce the risk of treatment-related MDS/AML.

Autotransplants in multiple myeloma: what have we learned?

Of 496 consecutive patients with multiple myeloma (MM) enrolled in clinical trials of tandem transplants with peripheral blood stem cells support, 470 (95%) completed the first autotransplant with melphalan 200 mg/m2 (MEL 200) and 363 (73%) completed the second transplant with either MEL 200 (40%), MEL 140 mg/m2 (MEL 140) with total-body irradiation (17%), or a combination of alkylating agents (16%), depending on the response status prior to the second transplant; 31 patients up to age 60 years received an allograft as the second transplant. The median interval from first to second transplant was 5 months. Treatment-related mortality during the first year after transplantation was 7%, and complete remission (CR) was obtained in 36%; the median durations of event-free survival (EFS) and overall survival (OS) after transplant were 26 and 41 months, respectively. Low beta 2-microglobulin ([B2M] < or = 2.5 mg/L) and C-reactive protein ([CRP] < or = 0.4 mg/dL) were the most significant standard parameters associated with both prolonged EFS and OS. Median OS exceeded 5.5 years in the one third of patients with both low B2M and CRP. When cytogenetics were included in the analysis, the presence of 11q abnormalities and/or complete or partial deletion of chromosome 13 ("unfavorable karyotype") became a dominant negative feature for both EFS and OS. In addition to these pretransplant parameters, attainment of CR and application of two transplants within 6 months both significantly extended EFS and OS. The group of patients (7%) with high B2M and CRP with either IgA isotype or unfavorable karyotype had the worst prognosis (EFS, < or = 10 months; median OS, < or = 12 months) and will require novel therapy. We conclude that tandem transplants are feasible in the majority of patients up to age 70 years, effecting CR in one third of all patients. Median OS was greater than 5.5 years, regardless of pretransplant features, if the first transplant was applied within 12 months of initial treatment and the second transplant no more than 6 months later.