Intensive treatment of multiple myeloma and criteria for complete remission

Tumor Reduction in Multiple Myeloma: New Concepts for New Therapeutics

The development of new resources for a more accurate diagnosis and response assessment in multiple myeloma has been a long process for decades, mainly since the middle of the 20th century. During this time, the succession of technical advances has run parallel to the better knowledge of disease biology and the availability of novel therapeutic strategies. The cornerstone of standardized criteria to uniformly evaluate the disease response in myeloma dates back to the 1990s when the key role of complete remission was established. Since then, different updates have been implemented according to available scientific evidences not always without certain controversies. The progressive improvements in survival results of myeloma patients and the growing quality of responses due to the novel therapies have led to the need of developing new tools for better monitoring of tumor burden. In this way, the concept of minimal residual disease and its key value based on the prognostic significance and the clinical relevance has been consolidated during the last years, overcoming the value of conventional response criteria or classical adverse prognosis markers. Nevertheless, its precise role in the clinical management of myeloma patients to detect early treatment failure and trigger early rescue strategies is still pending to be defined. In this review, we revisit the major milestones in the understanding of tumor reduction in multiple myeloma until the most recent imaging techniques or liquid biopsy approaches, including a critical view of conventional response criteria, whose backbone has remained unchanged during the last 20 years.

"I took the road less traveled, and that has made all the difference": Making a case for high-dose therapy and autologous stem cell transplantation in elderly patients with newly diagnosed multiple myeloma

LAY SUMMARY

Elderly patients with myeloma derive benefits from transplantation similar to those for younger patients. Age should not be the sole criterion for determining transplant eligibility. Performance status assessment and other tools for assessing comorbidities such as the Charlson comorbidity score may potentially help in determining transplant eligibility and will allow us to move away from our heavy reliance on numerical age.

Busulfan, melphalan, and bortezomib compared to melphalan as a high dose regimen for autologous hematopoietic stem cell transplantation in multiple myeloma: long term follow up of a novel high dose regimen

Melphalan at a dose of 200 mg/m² (MEL200) remains the standard high dose therapy before autologous stem cell transplantation (ASCT) for multiple myeloma (MM). Intensifying the high dose regimen has shown promising results. We report here 7-year follow up of our novel high dose regimen of busulfan and melphalan followed by bortezomib (BuMelVel). Forty-three MM patients received BuMelVel high dose therapy with pharmacokinetic adjusted busulfan. Outcomes were compared to a matched control cohort from the CIBMTR database (n = 162) receiving MEL200. The primary endpoint was progression free survival. Five year PFS was 47% v 30% (95% CI; 32-62) in favor or the BuMelVel group (95% CI; 23-37) (p = 0.05). In multivariate analysis for PFS, BuMelVel (HR 0.65; 95% CI 0.44-0.97)(p = 0.036) was predictive. Similar to recent reports of double alkylator therapy, although depth of response was similar between the BuMelVel group and MEL200, the BUMELVEL group experienced an improved PFS.

Autologous stem cell transplant in older patients (age ≥ 65) with newly diagnosed multiple myeloma: A systematic review and meta-analysis

OBJECTIVE

While autologous stem cell transplant (ASCT) is a standard of care for newly-diagnosed younger patients with multiple myeloma, its role in older patients remains controversial. We conducted a systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs) assessing the efficacy and toxicity of ASCT in older patients (age ≥ 65 years) with newly-diagnosed myeloma.

METHODS

We searched Medline, Embase, and the Cochrane database through February 2, 2018. The primary outcome was overall survival; secondary outcomes included progression-free survival, response rates and toxicity. The Grading of Recommendations Assessment, Development and Evaluation criteria (GRADE) method was used to assess certainty in evidence.

RESULTS

Of 8614 abstracts screened, six observational studies and two RCTs were included in the systematic review. For overall survival, pooled observational data favored ASCT (Hazard Ratio [HR] 0.44, 95% Confidence Interval [CI] 0.34-0.58, p < .0001), while the impact of the RCT data was uncertain (HR 0.94, 95% CI 0.25-3.54, p = .93). Observational data showed higher complete response rates with ASCT (odds ratio 5.06, 95% CI 2.60-9.88, p < .0001). Progression free survival benefit from the RCTs was uncertain (HR 1.05, 95% CI 0.36-3.12, p = .93). Data were insufficient to pool for toxicity.

CONCLUSION

For older patients with newly diagnosed multiple myeloma, ASCT may improve the overall survival and complete response rates based upon observational data although the quality of this evidence is very low. The role of ASCT in improving overall survival based upon RCT data remains uncertain with low quality of evidence. Our study highlights the urgent need for well-conducted studies to understand the role of ASCT in older patients.

Novel Treatments for Multiple Myeloma: What Role Do They Have in Older Adults?

Multiple myeloma is a malignant plasma cell disease, which typically affects older patients, with a median age at diagnosis of 70 years. The recent introduction of novel drugs and ongoing improvements in supportive care have significantly contributed to overall better management and outcomes for patients with multiple myeloma. Autologous stem-cell transplantation has been a standard part of therapy for myeloma patients for many years, first in younger patients and increasingly in older, and may still be considered in selected older patients with myeloma. In addition, in both newly diagnosed patients and in the relapsed/refractory setting, a number of novel agents tested in large phase III trials have yielded improvements in overall outcomes. As clinical trials under-enrol older patients and have stringent exclusion criteria, the data and results from them may not be generalizable to all older adults. In this review, we examine the treatment options for older adults with myeloma with a specific focus on the currently available data on novel agents in this cohort. The clinical efficacy and unique toxicity profile of each novel agent must be considered prior to the treatment plan in older adults.

Treatment of Multiple Myeloma with Autologous Blood Stem Cell Transplantation. Preliminary Results of an Italian Multicentric Pilot Study

Starting from May, 1991, 35 untreated myeloma patients entered a multicentric pilot study to evaluate the feasibility of a program of PBSC transplantation for previously untreated myeloma patients. The schedule was as follows: 2 cycles of VAD followed by CY, 7 g/mq + G-CSF (Granulokine, Roche) for 14 days, to increase and collect PBSC. The subsequent conditioning regimen was Melphalan + Busulfan followed by G-CSF. As maintenance R alpha-2 IFN was given, until relapse. The median follow-up is 14 months (4-22). On April 1993, 34 patients received at least 2 cycles of VAD, 27 were submitted to PBSC collection, 22 received conditioning regimen plus PBSC and 16 of them are in the maintenance treatment with IFN. Considering 28 patients for an intention to treat evaluation (35 -7 in treatment), responding patients are 71% with 46% who achieved CR. White cells and platelets raised to > 1000/mmc and >50,000/mmc after a median period of 10 and 13 days, from CY, and 11 and 14 days from transplant, respectively. Two patients relapsed, 2 others died while in PR because of CMV epatitis and candida pneumonia. The median number of CD34+ cells and CFU-GM was 24.75 x 106/kg b.w. and 28.1 x 104/kg b.w. respectively. In conclusion this treatment seems to be feasible and with low toxicity, but a longer follow-up is needed to evaluate the progression free survival of the high proportion of responding patients that we observed.

The Evolution of Prognostic Factors in Multiple Myeloma

Multiple myeloma (MM) is a heterogeneous hematologic malignancy involving the proliferation of plasma cells derived by different genetic events contributing to the development, progression, and prognosis of this disease. Despite improvement in treatment strategies of MM over the last decade, the disease remains incurable. All efforts are currently focused on understanding the prognostic markers of the disease hoping to incorporate the new therapeutic modalities to convert the disease into curable one. We present this comprehensive review to summarize the current standard prognostic markers used in MM along with novel techniques that are still in development and highlight their implications in current clinical practice.

Autologous haematopoietic cell transplantation in elderly patients with multiple myeloma

High-dose chemotherapy with melphalan followed by autologous haematopoietic cell transplantation (AHCT) is a standard of care in young patients (<65 years) with multiple myeloma. Most myeloma patients, however, are older than 65 years at the time of diagnosis, and the findings of numerous single-centre and registry studies provide evidence that AHCT can be a feasible and effective treatment option in these patients. Nevertheless, AHCT is not generally recommended as standard treatment in the elderly, due to the fact that a benefit of AHCT over conventional-dose therapy has not been demonstrated by prospective randomized trials. Yet, the use of AHCT has increased substantially in older patients in recent years, and an increasing number of reports suggest comparable outcomes for older and younger patients after AHCT. In this review we summarize the results of AHCT for elderly patients with multiple myeloma.

Content of endothelial progenitor cells in autologous stem cell grafts predict survival after transplantation for multiple myeloma

Multiple myeloma (MM) is considered an incurable B cell malignancy, although many patients can benefit from high-dose therapy with autologous stem cell transplantation (ASCT) as a first-line treatment. In non-Hodgkin lymphoma (NHL), ASCT is usually performed after relapse with curative intent. Disease progression is often associated with increased angiogenesis, in which endothelial progenitor cells (EPC) may have a central role. Here, we investigated the clinical impact of EPC levels in peripheral blood stem cell (PBSC) autografts for MM and NHL patients who received ASCT. EPC were identified by flow cytometry as aldehyde dehydrogenase(hi) CD34(+) vascular endothelial growth factor receptor 2(+) CD133(+) cells in both MM and NHL autografts. In MM, there was a positive correlation between EPC percentage and serum (s)-β2-microglobulin levels (r(2) = .371, P = .002). Unlike for NHL patients, MM patients with high numbers of infused EPC (EPC cells per kilogram) during ASCT had significant shorter progression-free survival (PFS) (P = .035), overall survival (P = .044) and time to next treatment (P = .009). In multivariate analysis, EPC cells per kilogram was a significant independent negative prognostic indicator of PFS (P = .03). In conclusion, the presence of high number of EPC in PBSC grafts is associated with adverse prognosis after ASCT in MM.

Re-use of the original infusional induction chemotherapy as salvage therapy in myeloma patients relapsing after one autograft

If standard infusional therapy (IC) has been used to treat myeloma at presentation, it is a matter of debate whether patients should receive the original induction therapy or a different drug combination in first relapse. Instinctively, most clinicians may switch treatment, particularly since the advent of new drugs for the treatment of myeloma. Hitherto, there has been no data on the efficacy of repeating standard IC in the salvage setting. We studied 62 myeloma patients whose initial treatment consisted of C-VAMP and a single high dose melphalan procedure and who were retreated with C-VAMP at the time of first relapse. Response to salvage C-VAMP was seen in 50% (95% confidence interval = 0.37-0.62) but we were unable to identify any predictors for response to salvage C-VAMP. Only patients resistant to salvage C-VAMP benefited from a second autograft. The survival of patients who responded to salvage C-VAMP was not prolonged by a second transplant. In conclusion, our data supports the use of C-VAMP for patients with myeloma in first relapse and suggest that only patients resistant to salvage C-VAMP should be offered a second autograft.

Allogeneic hematopoietic stem cell transplantation for multiple myeloma: curative but not the standard of care

PURPOSE OF REVIEW

Despite the curative potential of allogeneic hematopoietic stem cell transplantation (allo HSCT) for patients with multiple myeloma, and reduction of transplant-related mortality with nonmyeloablative transplant approaches, rates of acute and chronic graft-versus-host disease and disease progression remain high. It is unclear if nonmyeloablative transplants are more effective than autologous (auto). Novel promising drugs and maintenance treatment strategies following auto SCT may also delay allo transplantation. In this review, we summarize the emerging data on allo HSCT and provide suggestions for its optimal role in the treatment of myeloma.

RECENT FINDINGS

Large cooperative group studies comparing allo HSCT with auto SCT as frontline therapy have been performed with reduced intensity conditioning regimens using unmanipulated peripheral blood stem cells from human leukocyte antigen (HLA)-compatible donors and standard calcineurin inhibitor graft-versus-host disease prophylaxis. Two recent reports show conflicting data. Although the Blood and Marrow Transplant Clinical Trials Network 0102 study demonstrated no progression-free or overall survival advantage at 3 years, a European study demonstrated superior 5-year outcome after auto/HLA-matched sibling allo HSCT compared with tandem auto SCT in previously untreated multiple myeloma patients. The advent of maintenance therapy could potentially improve outcomes of both transplant types.

SUMMARY

High rates of acute and chronic graft-versus-host disease currently limit the implementation of nonmyeloablative allo HSCT. Novel approaches are required so that patients with myeloma can undergo allo HSCT before resistance develops to standard drug combinations.

Detection of clonal immunoglobulin gene rearrangements in the peripheral blood progenitor cells of patients with multiple myeloma: the potential role of purging with CD34 positive selection

Aims-To determine the extent of clonal cell contamination of peripheral blood progenitor cell (PBPC) collections in patients with multiple myeloma (MM) and to assess the purging efficacy of CD34 positive selection.Methods-PBPC collections from 29 patients with MM were analysed for the presence of clonal immunoglobulin heavy chain (IgH) gene rearrangements with a fluorescence based PCR technique. In addition, the PBPC from eight of the 29 patients were "purged" by selection of CD34 positive haematopoietic progenitors with an avidin-biotin immunoabsorption column (Ceprate). In each case the unmanipulated PBPC, CD34 positive and waste fractions were all assessed for the presence of clonal IgH rearrangements.Results-Clonal IgH rearrangements (identical with those demonstrated in diagnostic bone marrow samples) were demonstrated in 10 (35%) of 29 cases and seemed to be confined to those with significant residual bone marrow disease. Clonal rearrangements were evident in the PBPC of two of the eight patients who underwent CD34 selection; in both instances a "clonal purge" was seen as it was not possible to demonstrate the clonal rearrangement in the CD34 positive fraction. In four of the six remaining cases the normal polyclonal fingerprint could not be demonstrated in the CD34 positive fraction, which is consistent with a significant reduction in contaminating B cells.Conclusions-Clonal cells contaminate PBPC collections in a significant proportion of patients with MM and may be eliminated by CD34 positive selection.

The role of complete response in multiple myeloma

In multiple myeloma (MM), the impact of complete response (CR) could be shown only after introduction of high-dose therapy plus autologous stem cell transplantation (ASCT). In the context of ASCT, achieving CR (negative immunofixation and normal bone marrow) or at least very good partial response is associated with longer progression-free survival and in most studies longer survival. With novel agents, high CR rates are achieved and this prognostic impact of CR is being shown as well, both in relapsed and in newly diagnosed MM. However the benefit of CR achievement depends on the type of treatment and is not identical for all patients. In elderly patients, treatments inducing more CR may be more toxic. Although CR achievement is necessary in patients with poor-risk disease, it might not be as critical for long survival in more indolent MM. CR achievement is not the only objective of treatment because it is possible to further improve the depth of response and the outcome by continuing treatment after CR achievement. Finally, there are several levels of CR and in the future it will be necessary to confirm the prognostic impact of immunophenotypic or molecular CR or of CR defined by imaging procedures.

Influence of pre- and post-transplantation responses on outcome of patients with multiple myeloma: sequential improvement of response and achievement of complete response are associated with longer survival

PURPOSE

Complete response (CR) is considered an important goal in most hematologic malignancies. However, in multiple myeloma (MM), there is no consensus regarding whether immunofixation (IF)-negative CR, IF-positive near-CR (nCR), and partial response (PR) are associated with different survivals. We evaluated the prognostic influence on event-free survival (EFS) and overall survival (OS) of these responses pre- and post-transplantation in newly diagnosed patients with MM.

PATIENTS AND METHODS

We analyzed 632 patients from the prospective Grupo Español de Mieloma 2000 protocol who were uniformly treated with vincristine, carmustine, cyclophosphamide, melphalan, and predisone/vincristine, carmustine, adryamcine, and dexamethasone induction followed by high-dose therapy and autologous stem-cell transplantation.

RESULTS

Post-transplantation response markedly influenced outcomes. Patients achieving CR had significantly longer EFS (median, 61 v 40 months; P < 10(-5)) and OS (medians not reached; P = .01) versus patients achieving nCR, who likewise had somewhat better outcomes compared with patients achieving PR (median EFS, 34 months, P = .07 v nCR; median OS, 61 months, P = .04). EFS and OS and influence of response were similar among older (age 65 to 70 years) and younger (age < 65 years) patients. Similar findings were observed with pretransplantation response, with trends toward EFS (P = .1; P = .05) and OS (P = .1; P = .07) benefit in patients achieving CR versus nCR and PR, respectively. Post-transplantation response was markedly influenced by pretransplantation response; improvements in response were associated with prolonged survival.

CONCLUSION

Quality of response post-transplantation, notably CR, is significantly associated with EFS and OS prolongation in newly diagnosed patients with MM. There were trends toward similar associations with pretransplantation response status.

Pulmonary embolism in a patient with multiple myeloma receiving thalidomide-dexamethasone therapy

Massive pulmonary embolism is an uncommon complication of multiple myeloma treated with thalidomide-dexamethasone regimen. In 2006, multiple myeloma was diagnosed in a 72-year-old man, who received thalidomide-dexamethasone therapy. In January 2007, echocardiography and computerized tomography identified massive pulmonary embolism in the pulmonary arteries and a deep vein thrombus of the right leg. The patient also had an elevated concentration of B-type natriuretic peptide. After heparinization and warfarin therapy, the patient's condition improved. This is the first report of a patient with a rare complication of pulmonary embolism from thalidomide-treated multiple myeloma.

The role of high-dose chemotherapy supported by hematopoietic stem cell transplantation in patients with multiple myeloma: implications for nursing

Multiple myeloma (MM), a neoplastic proliferation of plasma cells originating from the B-cell line, is associated with deleterious complications and poor outcomes. The failure of conventional combination chemotherapies to improve the overall survival of patients with MM has led to the use of high-dose chemotherapy supported by stem cell transplantation (SCT). Although several novel therapies have emerged since the late 1990s, their survival benefits are undetermined. High-dose chemotherapy with SCT provides better response rates compared to conventional chemotherapy and yields a trend toward greater survival benefits, especially with the use of a tandem (two successive) transplantation strategy. This article discusses standard SCT in patients with MM and some of the new transplantation strategies, including tandem autologous SCTs and reduced-intensity nonmyeloablative allogeneic SCT, and their implications for nursing.

The evolving background for high-dose treatment for myeloma

In the constantly evolving field of myeloma, this special issue is slanted towards how the newer targeted treatments fit in with various transplantation strategies. High-dose treatment for myeloma with autologous stem cell transplantation started 25 years ago, with the consequence of producing complete remissions and a doubling of survival. Since then, its role has been refined and it has been accepted as standard treatment. The current challenge is to optimize its use into a background of the development, availability and regulatory approval of newer targeted therapies such as Thalidomide, Revlimid (Lenalidomide) and Velcade (Bortezomib). This special issue addresses these problems, and gives particular emphasis on the attainment of very long-term survival, with normal quality of life for patients with myeloma who do not necessarily need to be cured of their molecular disease, that is, they are 'operationally cured.' It is hoped that the reader will find the information in this issue useful in the day-to-day management of patients and we hope that this will also inspire new research directions designed to improve the outcome of patients with myeloma.

Absence of veno-occlussive disease in a cohort of multiple myeloma patients undergoing autologous stem cell transplantation with targeted busulfan dosage

BACKGROUND

Plasma concentrations of oral busulfan (BU) were measured in multiple myeloma (MM) patients undergoing autologous peripheral blood stem cell transplantation (ASCT) with a double alkylating conditioning protocol in order to individualise doses of BU based on individual pharmacokinetic parameters and to reduce toxicities related to BU exposure.

PATIENTS AND METHODS

Forty-four consecutive patients with MM participating in the co-operative Spanish protocol were prospectively evaluated. Conditioning regimen prior to autologous infusion consisted of BU followed by melphalan. BU pharmacokinetic parameters were estimated for each patient after the first dose based on measured concentrations and subsequent doses were modified as necessary to achieve target exposure.

RESULTS

Mean BU exposure (AUCss) (+/-DS) before dosage modification range from 3192 to 12 180 ng h/mL. Twenty-six out of 44 (59%) patients required dose adjustment. None of the patients developed hepatic veno-occlusive disease (VOD). Grade > or = II oropharyngeal mucositis was observed in the majority of patients (95%) and the severity of mucositis increased with increasing average steady-state BU plasma concentration. There were four treatment-related deaths: two patients died from multiorgan failure and two of respiratory infections. Of the remaining 40 patients, 15 were in complete remission with negative immunofixation, 21 in partial remission and four in stable disease 3 months after ASCT.

CONCLUSIONS

The results of the present study show the variability in BU pharmacokinetic parameters and suggest the possible relationship between toxicities and BU exposure. Individualising BU dosage in MM patients undergoing ASCT we observed the absence of VOD.

An elective single autograft with high-dose melphalan: single-center study of 451 patients

In all, 451 myeloma patients, 51% previously untreated, underwent elective single autotransplantation after 200 mg/m(2) melphalan between 1985 and 2001 at the Royal Marsden Hospital. The therapy sequence was: Induction (vincristine, doxorubicin, methylprednisolone+/-cyclophosphamide), marrow or filgrastim-mobilized blood stem cell harvest, autograft, and interferon-alpha2b maintenance. A total of 27 (6%) died of transplant-related toxicity, all within 3 months. Complete or near-complete remission was seen in 59% with an overall response rate of 91%. Subsequent disease progression was seen in 285, and 17 died of unrelated causes. In all, 206 patients were alive at the last follow-up, 6 months to 17.7 years post-transplant (median 65 months); 122 without disease progression at 6 months to 17.7 years (median 58 months). The median overall (OS) and event-free (EFS) survivals were 5.9 and 2.4 years, with 10-year OS and EFS probabilities of 31.4 and 16.5%, respectively. In Cox analysis, it was seen that significantly longer OS occurred for patients who had beta-2-microglobulin <3.5 mg/l (P<0.0001), age <60 years (P=0.001) and albumin > or =35 g/l (P=0.009). EFS was also longer if beta-2-microglobulin was <3.5 mg/l (P=0.0056) and patients were <60 years of age (P=0.033). We conclude that with a single planned autograft, patients with myeloma have an excellent outcome.

Long-term outcomes of previously untreated myeloma patients: responses to induction chemotherapy and high-dose melphalan incorporated within a risk stratification model can help to direct the use of novel treatments

Induction chemotherapy followed by high-dose melphalan (HDM) is the standard treatment for fitter patients with myeloma. The place of bortezomib and the thalidomide analogues within this treatment paradigm is yet to be established. We sought to identify patients who may benefit from the introduction of novel agents during their initial management. An intention-to-treat analysis was performed on 383 patients with newly diagnosed myeloma eligible for HDM to determine whether the extent of response to induction therapy and HDM correlated with long-term survival. Early response [complete response (CR) and partial response (PR)] to induction therapy was predictive of overall survival (OS) [median OS, 7.47 years for responders (CR and PR) versus 4.89 years for non-responders; P = 0.035]. The attainment of CR at 3 months post-HDM correlated with a prolonged progression-free survival (PFS) (median PFS, 7.4 years in CR group versus 5.3 years in non-CR group; P = 0.023). This data suggests that, at every stage of treatment, the aim should be to achieve CR. Patients with suboptimal responses could be offered alternative therapy. We propose a multiparametric risk-adapted model that includes response to induction chemotherapy and HDM, for identifying patients who may benefit from novel approaches to treatment.

Prospective randomised trial of amifostine cytoprotection in myeloma patients undergoing high-dose melphalan conditioned autologous stem cell transplantation

In this prospective multicentre trial, 90 patients undergoing autologous stem cell transplantation (ASCT) were randomised to receive (n=43) or not receive (n=47) amifostine 910 mg/m(2) prior to melphalan 200 mg/m(2). Patients were monitored for regimen-related toxicity, engraftment, supportive care, response and survival. Both groups underwent ASCT at a median of 8 months from diagnosis and were matched for disease characteristics, prior therapy and pre-ASCT disease responsiveness. Amifostine infusional side-effects were frequent, occurring in 65% of patients, but of mild severity. Amifostine use was associated with a reduction in the median grade of oral mucositis (1 vs 2, P=0.01) and the frequency of severe (WHO grades 3 or 4) mucositis (12 vs 33%, P=0.02), but no reduction in the requirement for parenteral nutrition or analgesic use. Conversion to complete remission post-ASCT occurred in 30 and 14% of the amifostine and control groups, respectively (P=0.09). With a median follow-up of 35 months, there was no statistically significant difference between the median progression-free or overall survival times for the two groups. We conclude that amifostine can be safely administered prior to high-dose melphalan and significantly reduces the frequency and severity of therapy-induced oral mucositis.

Extramedullary vs medullary relapse after autologous or allogeneic hematopoietic stem cell transplantation (HSCT) in multiple myeloma (MM) and its correlation to clinical outcome

Risk-adapted treatment of multiple myeloma (MM) includes autologous (auto-) and allogeneic (allo-) hematopoietic stem cell transplantation (HSCT). Case reports on extramedullary (EM) compared to bone marrow (BM) relapse after HSCT suggest a dismal prognosis. We compared the outcome of 78 MM patients relapsing after auto- (group A: n = 53) or allo- (group B: n = 25) HSCT, stratified into BM (64 patients) vs EM (14 patients) relapse. The relapse-specific groups were also compared with respect to risk factors, including age, beta2-microglobulin, pretreatment, cytogenetics and stage. EM relapse sites were lungs (5), soft tissue (4), pericardium (2), bone (1), skin (1) and CNS (1). As of May 2004, the overall (OS) and progression-free (PFS) survival after HSCT in patients relapsing from EM sites was not significantly different from BM relapse patients, both after auto- and allo-HSCT. Although MM patients relapsing from EM sites after allo-HSCT used to be regarded as having few therapeutic options, we observed encouraging responses to donor lymphocyte infusions (DLI). Treatment responses to DLIs were observed in 5/9 (56%) BM relapse patients, and in 3/4 (75%) EM relapse patients. These observations suggest that EM relapse after HSCT is common and needs an individualized diagnostic and therapeutic approach in MM during clinical follow-up after HSCT.

Serum syndecan-1, basic fibroblast growth factor and osteoprotegerin in myeloma patients at diagnosis and during the course of the disease

Neovascularisation and bone resorption are related to myeloma disease activity.

OBJECTIVES

To investigate the possible prognostic importance of serum syndecan-1, basic fibroblast growth factor (bFGF) and osteoprotegerin (OPG) levels, the relationship between them, with parameters of disease activity and the effect of treatment on their levels.

PATIENTS AND METHODS

Twenty-seven patients were studied from diagnosis and an additional five from remission, for a median follow-up of 40 months. Twenty-three patients received chemotherapy plus bisphosphonates and nine only bisphosphonates. Sera from 11 healthy individuals (HI) were used as controls. Cytokines were determined by commercially available enzyme-linked immunosorbent assays (ELISA) kits.

RESULTS

In HI, median syndecan-1 was 40 ng/mL (28-75), bFGF 8 pg/mL (7-30), OPG 35 pg/mL (4-100). Pretreatment median serum syndecan-1 was 177.5 ng/mL (34-3500), bFGF 11.5 pg/mL (8-65) and OPG 100 pg/mL (4-1000). Pretreatment syndecan-1, bFGF and OPG serum levels were increased in patients compared with HI (P = 0.001, 0.03 and 0.01, respectively). Syndecan-1 and bFGF levels were correlated with stage (P = 0.004 and 0.03, respectively). Both syndecan-1 and OPG levels were correlated with beta2M (P = 0.04 and 0.01, respectively). Patients with elevated syndecan-1 and bFGF serum levels had shorter survival than patients with normal levels (P = 0.01 and 0.05, respectively). After chemotherapy syndecan-1 and OPG levels were found to be decreased in responders and syndecan-1 level was reduced in patients receiving bisphosphonates alone.

CONCLUSIONS

Pretreatment syndecan-1, bFGF and OPG levels were found to be increased at diagnosis. Syndecan-1 and OPG fluctuated according to MM activity. Elevated serum syndecan-1 and bFGF levels predicted short survival.

Single versus double autologous stem-cell transplantation for multiple myeloma

BACKGROUND

We conducted a randomized trial of the treatment of multiple myeloma with high-dose chemotherapy followed by either one or two successive autologous stem-cell transplantations.

METHODS

At the time of diagnosis, 399 previously untreated patients under the age of 60 years were randomly assigned to receive a single or double transplant.

RESULTS

A complete or a very good partial response was achieved by 42 percent of patients in the single-transplant group and 50 percent of patients in the double-transplant group (P=0.10). The probability of surviving event-free for seven years after the diagnosis was 10 percent in the single-transplant group and 20 percent in the double-transplant group (P=0.03). The estimated overall seven-year survival rate was 21 percent in the single-transplant group and 42 percent in the double-transplant group (P=0.01). Among patients who did not have a very good partial response within three months after one transplantation, the probability of surviving seven years was 11 percent in the single-transplant group and 43 percent in the double-transplant group (P<0.001). Four factors were significantly related to survival: base-line serum levels of beta2-microglobulin (P<0.01) and lactate dehydrogenase (P<0.01), age (P<0.05), and treatment group (P<0.01).

CONCLUSIONS

As compared with a single autologous stem-cell transplantation after high-dose chemotherapy, double transplantation improves overall survival among patients with myeloma, especially those who do not have a very good partial response after undergoing one transplantation.

High-dose chemotherapy with hematopoietic stem-cell rescue for multiple myeloma

BACKGROUND

High-dose therapy with supporting autologous stem-cell transplantation remains a controversial treatment for cancer. In multiple myeloma, first-line regimens incorporating high-dose therapy yield higher remission rates than do conventional-dose treatments, but evidence that this translates into improved survival is limited.

METHODS

In this multicenter study, the Medical Research Council Myeloma VII Trial, we randomly assigned 407 patients with previously untreated multiple myeloma who were younger than 65 years of age to receive either standard conventional-dose combination chemotherapy or high-dose therapy and an autologous stem-cell transplant.

RESULTS

Among the 401 patients who could be evaluated, the rates of complete response were higher in the intensive-therapy group than in the standard-therapy group (44 percent vs. 8 percent, P<0.001). The rates of partial response were similar (42 percent and 40 percent, respectively; P=0.72), and the rates of minimal response were lower in the intensive-therapy group than in the standard-therapy group (3 percent vs. 18 percent, P<0.001). Intention-to-treat analysis showed a higher rate of overall survival (P=0.04 by the log-rank test) and progression-free survival (P<0.001) in the intensive-therapy group than in the standard-therapy group. As compared with standard therapy, intensive treatment increased median survival by almost 1 year (54.1 months [95 percent confidence interval, 44.9 to 65.2] vs. 42.3 months [95 percent confidence interval, 33.1 to 51.6]). There was a trend toward a greater survival benefit in the group of patients with a poor prognosis, as defined by a high beta2-microglobulin level (more than 8 mg per liter).

CONCLUSIONS

High-dose therapy with autologous stem-cell rescue is an effective first-line treatment for patients with multiple myeloma who are younger than 65 years of age.

Idarubicin containing regimen in multiple myeloma: preliminary results of a pilot study using a modified "TANDEM" transplant program

Tandem autologous transplant actually represents a challenge in multiple myeloma treatment, but the best conditioning regimen is still under investigation. With the aim of evaluating the feasibility of a modified tandem transplant strategy, we treated 10 multiple myeloma patients after conventional first line chemotherapy with a two step conditioning regimen consisting of high-dose melphalan (200 mg/m2) followed by high-dose melphalan (180 mg/m2) together with indarubicin (15 mg/sqm2 c.i. x 3 days) both with peripheral stem cell support. At first transplant, the median age wasyears, performance status was good and disease status was CR in 2 patients and PR in the rest. At the end of the first transplant, 70% of patients achieved CR and only mild toxicity was observed. After the second transplant further improvement of the response rate was obtained with 90% CR. However, we observed three toxic early infection-related deaths from CMV and legionella pneumonia at day + 17, +26, +54 after transplantation. Although this schedule seems to be effective in terms of response rate, the 30% TRM imposes an anthracycline dose-reduction with careful patient selection. This approach could reduce the toxic effects and maintain the efficacy of therapy at the same time.

Peripheral blood stem cell contamination evaluated by a highly sensitive molecular method fails to predict outcome of autotransplanted multiple myeloma patients

To evaluate the clinical impact of minimal residual disease in multiple myeloma, apheretic products from 51 autotransplanted patients were tested by fluorescent (GeneScan) polymerase chain reaction (PCR). Sixty-nine per cent of harvests were contaminated when evaluated for IgH rearrangement. Forty-six patients responded to transplant, with 52.9% achieving complete response (CR). The clinical response of patients was significantly influenced by the number of re-infused CD34+ cells. Positive PCR results of re-infused harvests were not significantly related to patient outcome. Median overall survival (OS) was 33 months, and a significant advantage for patients transplanted by 12 months from diagnosis was observed. Moreover, OS was longer for patients receiving PCR-negative stem cells, with 72% of patients surviving to 70 months in the group receiving PCR-negative harvests vs 48% in the group transplanted with contaminated precursors (not statistically significant). Ex vivo purging caused a reduction of contamination of up to 3 logs; nevertheless, 80% of purged harvests remained PCR-positive and the purging procedure did not alter response or survival rates. Thus, the failure of a predictive role for this highly sensitive molecular method could be explained by the assumption that in vivo persisting malignant cells are the true source of relapse in MM.

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

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

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

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

A pilot study on feasibility and efficacy of amifostine preceding high-dose melphalan with autologous stem cell support in myeloma patients

To evaluate feasibility and potential efficacy of amifostine (AMI) in the prevention of toxicities associated with high-dose melphalan (MEL), ten myeloma patients received AMI 910 mg/m2 in 15 min infusion preceding MEL 200 mg/m2 followed by stem cell infusion (AMI group). Hematologic and extra-hematologic toxicities as well as the need for supportive care observed in the AMI group were compared with ten myeloma patients treated in an identical protocol but without AMI. Hypotension was the most important adverse event of AMI infusion. No differences were observed in the time of engraftment between the AMI group and the control group neither was there any difference in the need for supportive care. Oral mucositis grade >2 was observed in 30% of the patients in both groups. Diarrhea grade >2 occurred only in two AMI patients but in five control patients. AMI preceding high-dose MEL is feasible, although adverse events are observed in some patients. Whether AMI could reduce the gastrointestinal toxicity associated with high-dose MEL can be reliably assessed only in prospective randomized trials.

Thalidomide for the treatment of refractory multiple myeloma: association of plasma concentrations of thalidomide and angiogenic growth factors with clinical outcome

Recent reports showed that thalidomide has anti-angiogenic activity and is effective for the treatment of refractory multiple myeloma (MM). We examined the relationship between the clinical efficacy and adverse effects of thalidomide and the plasma concentrations of this drug as well as angiogenic growth factors in refractory MM. Ten out of twenty-four evaluable patients (42%) showed more than 25% reduction of M-protein, and eight (33%) achieved more than 50% reduction. These changes were associated with restoration of anemia and recovery of normal immunoglobulin level. Somnolence and headache, constipation, peripheral neuropathy and skin rash were frequently observed, but were well tolerated. However, grade 2 - 4 severe neutropenia was also observed in nine cases. These adverse effects other than neutropenia occurred more frequently in the patients with higher plasma concentrations of thalidomide (2.0 microg/ml at 12 h after the last administration) and were readily alleviated by dose reduction. In contrast, neutropenia developed regardless of the plasma concentration. Plasma concentrations of angiogenic growth factors were frequently elevated before treatment. After thalidomide treatment, these growth factor levels tend to decrease to near-normal ranges in responders but were still high in most non-responders. After thalidomide treatment, plasma vascular endothelial growth factor (VEGF) level was significantly reduced in responders (P = 0.025), but not in non-responders (P = 0.37). Reduction of plasma VEGF level might be an important indicator for anti-myeloma effect of thalidomide.

Management of multiple myeloma

There has been no improvement in the treatment of multiple myeloma (MM) during the last decades and two meta-analyses of randomized trials recorded no significant survival benefit for combination chemotherapy compared to the classic melphalan-prednisone combination. However the past 15 years has seen several innovative strategies which have dramatically modified the management of MM. In younger patients, high-dose therapy with autologous stem cell transplantation is considered to be superior to conventional chemotherapy and is used as part of front-line therapy. A number of issues have been addressed in recent trials in order to improve the results of autologous transplantation (source of stem cells, conditioning regimen, impact of double transplants, maintenance therapy). Bisphosphonates reduce the incidence of skeletal-related events and improve the quality of life. Recombinant erythropoietin reduces red blood cell transfusion need and improves the quality of life. Thalidomide has been introduced more recently. Phase II studies with thalidomide alone or combined with dexamethasone have shown impressive response rates and this drug is currently being evaluated as part of front-line therapy. Finally, analysis of prognostic factors such as beta 2 microglobulin and cytogenetics define subgroups of patients with a completely different outcome and help the process of selecting therapeutics strategies.

Methylation is an inactivating mechanism of the p16 gene in multiple myeloma associated with high plasma cell proliferation and short survival

In order to gain further insights into the role of the p16 gene in cell cycle regulation and the prognostic implications of its inactivation, we investigated the methylation status of the p16 gene in 98 untreated patients using a polymerase chain reaction assay based on the inability of some restriction enzymes to digest methylated sequences. Forty-one patients showed a p16 methylated gene (42%). The percentage of S-phase plasma cells (PC) in these patients was almost three times higher than in those with an unmethylated p16 gene (4.16% +/- 3.37%vs 1.5% +/- 1.41%, P < 0.001). The presence of p16 methylation also correlated with both elevated beta2-microglobulin serum levels and high C-reactive protein values. Patients with a p16 methylated gene had shorter overall and progression-free survival than those patients without p16 methylation. However, this feature did not retain independent prognostic influence on multivariate analysis, probably due to its association with the S-phase PC, which had more potent statistical significance in the Cox model. These findings showed methylation of the p16 gene was a frequent event inMM patients at diagnosis, and was associated with an increased proliferative rate of plasma cells and a poor prognosis, indicating an important role for p16 gene in the cell cycle regulation of multiple myeloma tumour cells, and thus in the clinical outcome of the disease.

Minimal residual disease monitoring in multiple myeloma

Traditionally, response to treatment in multiple myeloma has been measured by the serum or urinary paraprotein and the percentage of plasma cells in the bone marrow. The use of allogeneic and autologous transplantation has increased the complete response rate and overall survival in patients with myeloma, and in order to assess the effects of such treatments accurately more sensitive methods for assessing residual disease have been introduced. The aim of this chapter, therefore, is to describe the available techniques to assess response, monitor residual disease and predict relapse in myeloma. The traditional techniques of paraprotein measurement using electrophoresis and immunofixation are compared with more sensitive approaches involving the polymerase chain reaction for detecting rearrangements of the immunoglobulin heavy-chain region and flow cytometry for detecting malignant plasma cells. Emphasis is placed on the advantages and disadvantages of each method and its utility in the clinical setting.

Meningeal relapse after double peripheral blood stem cell transplantation in IgD myeloma

A 54-year-old man diagnosed with IgD myeloma (stage IIIA) in complete remission (CR) received peripheral blood stem cell transplantation (PBSCT) twice with an interval of 4 months using high-dose melphalan 200mg/m2. However 9 months after the second PBSCT, he was readmitted because of lumbago, lower left hemiparesis, speech disturbance and left facial nerve palsy. A lumbar puncture revealed myeloma cells in the cerebrospinal fluid (CSF). The patient did not respond to any salvage chemotherapy and died of sepsis 27 months after the initial diagnosis. The findings in this patient suggest that another treatment modality including prophylactic intrathecal injection of an anti-cancer drug as well as allogeneic cell therapy is probably necessary in patients with high-risk IgD myeloma.

Myeloablative treatments for multiple myeloma: update of a comparative study of different regimens used in patients from the Spanish registry for transplantation in multiple myeloma

After a previous analysis that did not detect clear differences in the results of three conditioning regimens used for autologous stem cell transplantation (ASCT) in patients from the Spanish Registry for Transplant in Multiple Myeloma (MM), we have updated the registry, including a larger number of cases and a fourth conditioning regimen with a longer follow-up. We evaluate 472 MM patients treated with 200 mg/m2 melphalan (MEL200), 135 patients treated with 140 mg/m2 melphalan plus total body irradiation [(MEL140 + TBI)], 186 patients treated with 12 mg/kg busulphan plus 140 mg/m2 melphalan (BUMEL) and 28 patients treated with 14 mg/kg busulphan followed by cyclophosphamide 120 mg/kg (BUCY). There were no significant differences in respect to either transplant related death or haematological recovery, regardless of growth factor use, between the four conditioning programs. Nevertheless, hospitalization time with MEL200 was less than with BUMEL when growth factors were used (19+/-9 vs. 25+/-9 days, P = 0.009) and less than with MEL140 + TBI without growth factors (20+/-8 days vs. 27+/-9 days, P = 0.002). In patients with measurable disease at ASCT (non-complete remission [CR]), BUMEL achieved a 51% CR vs. 43%-31% in the other groups (P = 0.007). The response rate for patients in partial remission (PR) at ASCT was 100% with BUMEL vs. 93%-86% in the other groups (P between 0.02 and 0.0007). The median overall survival (OS) for the BUMEL group was 57 months (95% confidence interval [CI]: 51-78) as compared to 45 (CI: 36-64) months for the MEL200 group and 39 (CI: 28-72) months for the MEL140 + TBI and BUCY groups. The median event free survival (EFS) was longer in the BUMEL group [30 (CI: 22-44) mo] than in the MEL200 [22 (CI: 18-26) mo], BUCY [23 (CI: 11-50) mo] or MEL140 + TBI groups [20 (CI: 15-29) mo]. Nevertheless, the differences in OS and EFS did not reach statistical significance in either the univariate analysis or the multivariate analysis adjusted with other high prognostic weight factors. As in the initial study, differences in regards to the anti-myeloma effect of the conditioning regimens are not conclusive. However, the better response rates associated with the favorable tendency in outcome achieved with BUMEL, continue to justify further prospective studies.

Some early phase II trials in previously untreated multiple myeloma: The Royal Marsden experience

Multiple myeloma is at a stage today where acute leukemia was in the 1960s and 1970s when the aim was to attain complete remission (CR), which would translate into prolonged overall survival (OS) and a cure. The Royal Marsden group was the first to establish a dose-response effect for melphalan leading to CR in patients with myeloma. Since then, different strategies have been developed to improve the results of high-dose therapy, including alternating conditioning regimens, peripheral blood stem cells (PBSC) as a source of stem cells, purging techniques to decrease graft contamination by the myeloma cell, increased dose intensity by means of tandem transplants, and finally, allogeneic matched or unmatched stem cell transplantation. Components of treatment offered at Royal Marsden since 1980 are upfront high-dose melphalan (HDM) 140 mg/m(2), induction infusional chemotherapy followed by consolidation with HDM with autotransplantation, and maintenance with interferon-alpha2b (IFN) (collectively termed sequential therapy). Each of these components has shown benefits in selected studies and together they have dramatically improved the outlook for patients with myeloma.

Comparison of new patients with Bence-Jones, IgG and IgA myeloma receiving sequential therapy: the need to regard these immunologic subtypes as separate disease entities with specific prognostic criteria

Of the 61 newly diagnosed patients with Bence-Jones (BJ) myeloma presenting to our centre between May 1986 and December 1997, 53 received sequential therapy (ST) comprising infusional chemotherapy (IC) followed by high-dose therapy and autotransplantation with interferon-alpha2b maintenance. The outcome was compared with 153 IgG and 39 IgA similarly treated myeloma patients. Response to IC and high-dose was comparable between the three subtypes but a significantly higher proportion of patients with BJ myeloma failed to receive high-dose compared to IgG (P = 0.003) and IgA (P = 0.04) myeloma. Median overall survival (OS) of patients with BJ myeloma (2.8 years) and event-free survival (EFS, 1.2 years) was significantly shorter than for patients with IgG myeloma (4.5 years, P = 0.03 and 2.1 years, P = 0.03, respectively). However, among those patients who achieved complete remission there was no difference in OS and EFS between IgG and BJ myeloma. In distinction to IgG myeloma where age and beta2M were significant, Cox analysis on presentation features identified performance status and urine total protein as having significant impact on OS. We conclude that achieving CR is an important treatment aim in patients with BJ myeloma, conferring a similar outlook on survival as in patients with the IgG subtype, and there is a need to consider different subtype-specific staging systems when evaluating the results of published or ongoing therapeutic trials.

Thiotepa, busulfan, cyclophosphamide (TBC) and autologous hematopoietic transplantation: an intensive regimen for the treatment of multiple myeloma

The study was designed to evaluate the efficacy and safety of an intensive, tri-alkylator conditioning regimen, consisting of thiotepa, busulfan and cyclophosphamide (TBC), prior to autologous hematopoietic cell transplantation in patients with multiple myeloma (MM) and to analyze factors associated with outcome. One hundred and twenty patients with MM received high-dose chemotherapy with TBC followed by autologous bone marrow (n = 24) or peripheral blood stem cell (PBSC) transplantation (n = 96). Fifty-four patients had chemosensitive disease and 66 had refractory disease at the time of transplantation. The overall response rate was 81% and the complete remission (CR) rate was 26%. Patients with chemosensitive disease had a CR rate of 52% vs 5% for patients with refractory disease. Multivariable analysis determined disease status at transplant as the factor most likely associated with long survival. Estimated median survival was 48, 35 and 9 months for patients with chemosensitive, primary refractory or disease in refractory relapse, respectively. Short interval from diagnosis to transplant among patients with primary refractory disease and younger age were also favorable prognostic factors for survival. Patients with refractory disease pre-transplant who achieved remission criteria rapidly after treatment had a worse outcome than the slow responders. Treatment-related mortality with the introduction of PBSC and better supportive care was 4.8%. In conclusion, TBC is an effective and relatively well-tolerated intensive conditioning regimen in patients with MM. A more favorable outcome was observed in patients with chemosensitive disease and with early treatment for primary refractory disease. TBC merits further study in these subgroups and comparison with alternative regimens in prospective studies is warranted.

The impact of attaining a minimal disease state after high-dose melphalan and autologous transplantation for multiple myeloma

Initial studies with high-dose therapy (HDT) in myeloma suggest some beneficial effects of attaining a complete response (CR); however, the effect on survival is difficult to assess owing to inconsistencies in the definition of response between studies. We have analysed 96 newly diagnosed patients aged less than 65 years who received HDT and assessed the effect of response on survival using electrophoresis, immunofixation and fluorescent IgH polymerase chain reaction (PCR) to define CR. Patients received induction chemotherapy with C-VAMP (adriamycin, vincristine, methylprednisolone, cyclophosphamide) followed by melphalan 200 mg/m2 and reinfusion of peripheral blood stem cells. There was a high response to C-VAMP [CR = 24%, partial response (PR) = 64%], with all but one patient improving the depth of response after HDT (CR = 69%, PR = 31%). The progression-free survival (PFS) and overall survival (OS) were excellent at a median of 46.4 months and 72+ months. There was a trend towards an improved PFS in patients with an immunofixation-negative CR compared with patients with a PR (49.4 months, 41.14 months; P = 0.26). This was not evident when electrophoresis was used to define CR. The method used to define CR did not impact on the overall survival and fluorescent IgH PCR failed to add any additional prognostic information. This study supports the widespread use of the European Bone Marrow Transplantation group (EBMT) response criteria and suggests that immunofixation should be performed on all patients who become electrophoresis negative.

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

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

Remission status defined by immunofixation vs. electrophoresis after autologous transplantation has a major impact on the outcome of multiple myeloma patients

We have retrospectively analysed 344 multiple myeloma (MM) patients (202 de novo patients) treated in a non-uniform way in whom high-dose therapy and autologous stem cell transplantation (ASCT) response was simultaneously measured by both electrophoresis (EP) and immunofixation (IF). Patients in complete remission (CR) by EP were further subclassified as CR1 when IF was negative and CR2 when it remained positive. Partial responders (PR) were also subclassified as PR1 (very good PR, > 90% reduction in M-component) or PR2 (50-90% reduction). CR1 patients showed a significantly better event-free survival (EFS) [35% at 5 years, 95% confidence interval (CI) 17-53, median 46 months] and overall survival (OS) (72% at 5 years, CI 57-86, median not reached) compared with any other response group (univariate comparison P < 0.00000 to P = 0. 004). In contrast, comparison of CR2 with PR1 and with PR2 did not define different prognostic subgroups (median EFS 30, 30 and 26 months respectively, P = 0.6; median survival 56, 44 and 42 months respectively, P = 0.5). The non-responding patients had the worst outcome (5-year OS 8%, median 7 months). Multivariate analysis confirmed both the absence of differences among CR2, PR1 and PR2 and the highly discriminatory prognostic capacity of a three-category classification: (i) CR1 (ii) CR2 + PR1 + PR2, and (iii) non-response (EFS P < 0.00000; OS P < 0.00000; both Cox models P < 0.00000). In the logistic regression analysis, the factors significantly associated with failure to achieve CR1 were the use of two or more up-front chemotherapy lines, status of non-response pre-ASCT and inclusion of total body irradiation (TBI) in the preparative regimen. Tandem transplants or the use of multiple agents (busulphan and melphalan) in the preparative regimen resulted in a higher CR1 level; none of the biological factors explored influenced the possibility of achieving CR1. These results confirm that, in MM patients undergoing ASCT, achieving a negative IF identifies the patient subset with the best prognosis; accordingly, therapeutic strategies should be specifically designed to achieve negative IF.

Conditioning regimens in autologous stem cell transplantation for multiple myeloma: a comparative study of efficacy and toxicity from the Spanish Registry for Transplantation in Multiple Myeloma

High-dose chemoradiotherapy conditioning regimens for autologous stem cell transplantation (ASCT) are generally held to give similar results in multiple myeloma (MM), but no specific comparative study has been published. We addressed this issue by comparing the main high-dose chemoradiotherapy regimens used in the Spanish Registry. Patient cohorts included 315 cases treated with 200 mg/m2 melphalan (MEL200), 127 patients with 140 mg/m2 melphalan plus total body irradiation (MEL140 + TBI) and 121 cases with 12 mg/kg busulphan plus 140 mg/m2 melphalan (BUMEL). After ASCT, granulocyte and platelet recovery time was similar in all conditioning groups. There were no differences in transplant-related mortality. All regimens yielded a similar response in reference to pre-ASCT MM status, although BUMEL produced a slightly better overall response when compared with the other regimens (97% vs. 89% and 92%, P = 0.003). The 5-year overall survival (OS) with BUMEL was 47% [95% confidence interval (CI) 26-68] compared with 43% (CI 31-54) for MEL140 + TBI and 37% (CI: 18-56) for MEL200. The median survival for the BUMEL group was 64 months compared with 45 and 37 months for the MEL200 and MEL140 + TBI groups respectively. These differences were non-significant (P = 0.2). The median event-free survival (EFS) was better for BUMEL (32 months) than for MEL200 (22 months) or for MEL140 + TBI (20 months). The differences in EFS between BUMEL and the other conditioning regimens reached statistical significance (P = 0.01). Nevertheless, the adjusted multivariate analysis for OS and EFS revealed that the conditioning regimens had no independent prognostic value. We concluded that three different conditioning regimens, commonly used for ASCT in MM, have a similar antimyeloma effect. However, the trend for better results observed in our series with BUMEL requires a prospective trial.