High-dose melphalan and autologous bone marrow transplantation as consolidation in previously untreated myeloma

DNA Adducts in Cancer Chemotherapy

DNA adducting drugs, including alkylating agents and platinum-containing drugs, are prominent in cancer chemotherapy. Their mechanisms of action involve direct interaction with DNA, resulting in the formation of DNA addition products known as DNA adducts. While these adducts are well-accepted to induce cancer cell death, understanding of their specific chemotypes and their role in drug therapy response remain limited. This perspective aims to address this gap by investigating the metabolic activation and chemical characterization of DNA adducts formed by the U.S. FDA-approved drugs. Moreover, clinical studies on DNA adducts as potential biomarkers for predicting patient responses to drug efficacy are examined. The overarching goal is to engage the interest of medicinal chemists and stimulate further research into the use of DNA adducts as biomarkers for guiding personalized cancer treatment.

Optimizing high dose melphalan

Melphalan, has been a major component of myeloma therapy since the 1950s. In the context of hematopoietic cell transplantation (HCT), high dose melphalan (HDM) is the most common conditioning regimen used due to its potent anti-myeloma effects and manageable toxicities. Common toxicities associated with HDM include myelosuppression, gastrointestinal issues, and mucositis. Established approaches to reduce these toxicities encompass dose modification, nausea prophylaxis with 5HT3 receptor antagonists, cryotherapy, amifostine use, and growth factors. Optimization of melphalan exposure through personalized dosing and its combination with other agents like busulfan, or bendamustine show promise. Propylene glycol-free melphalan (Evomela) represents a novel formulation aiming to enhance drug stability and reduce adverse effects. This review explores strategies to enhance the efficacy and mitigate the toxicity of HDM in multiple myeloma. Future directions involve exploring these strategies in clinical trials to improve the safety and efficacy of HDM, thereby enhancing outcomes for multiple myeloma patients undergoing autologous HCT.

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.

Autologous Stem Cell Transplantation in Multiple Myeloma with Renal Failure: Friend or Foe?

Autologous stem cell transplantation (ASCT) is a standard treatment for multiple myeloma (MM), but the clinical response and renal curative effect in MM patients with renal failure (RF) remain controversial. The myeloma kidney disease has different types, and most are due to the direct toxic effects of light chain. Although ASCT can effectively clear the light chain, the data of renal function improvement are still limited. We reviewed the published literatures, focusing on the prospective studies, the retrospective analysis studies, and the case reports. RF patients who received ASCT displayed a low survival rate (OS: HR 1.95, 95% CI 1.020 to 3.720; I² = 64.9%, P = 0.014) and a shorter EFS/PFS (EFS/PFS: HR 1.53, 95% CI 1.090 to 2.140; I² = 0%, P = 0.669). However, ASCT was feasible and could have the similar clinical response outcomes compared with the normal renal function (CR: OR 1.013, 95% CI 0.569 to 1.804; I² = 48.5%, P = 0.101; PR: OR 1.013, 95% CI 0.342 to 1.226; I² = 46.3%, P = 0.144). Moreover, MM with RF after ASCT had a good improvement of renal function and melphalan is still an important factor affecting the treatment of ASCT.

Differences in Transplant-Related Complications between Hematologic Malignancies and Solid Tumors Receiving High-Dose Chemotherapy and Autologous Peripheral Blood Stem Cell Transplantation

Multiple factors contribute to transplant-related complications after high-dose chemotherapy followed by autologous peripheral blood stem cell transplantation, including conditioning regimens, number of infused stem cells and clinical characteristics of patient at transplant. We compared the transplant-related complications of 141 patients affected with hematological malignancies with those of 109 patients with solid tumors. The total number of peripheral blood stem cell transplantations performed was 339. High-dose chemotherapy mainly consisted of melphalan-, busulphan- or thiotepa-based regimens. Despite the equal number of infused CD34+ cells, patients with a hematological malignancy showed a slower absolute neutrophil count (days to neutrophils >0.5 x 109/L, 10.6 ± 3.6 for hematological malignancies versus 9.1 ± 1.2 for solid tumors, P <0.0001) and platelet recovery (days to platelets >20 x 109/L, 16.4 ± 9.8 for hematological malignancies versus 12.3 ± 4.1 for solid tumors, P <0.0001) than patients with a solid tumor. A significantly higher requirement of red blood cell (3.3 ± 4.1 versus 2.0 ± 1.9, P <0.0029) and platelet units (7.5_± 10.4 versus 4.2 ± 3.4, P <0.0001) was observed for hematological malignancies than for solid tumors. Five graft failures were documented exclusively in patients with a hematological malignancy. Moreover, such patients displayed a longer duration of mucositis (P <0.0028) and hospital stay (P <0.0001), but no difference was observed in terms of febrile episodes. Transplant-related mortality was similar between the two groups. In conclusion, patients with a hematological malignancy overall have more complications than those with a solid tumor.

Cost of Treatment of Multiple Myeloma in a Public Sector Tertiary Care Hospital of North India

Multiple myeloma (MM) is a neoplastic disorder, which accounts for 13% of all hematological malignancies globally. While, conventional chemotherapy used to be the mainstay treatment for the disease, the landscape of treatment witnessed a paradigm shift with the introduction of high-dose chemotherapy and autologous stem cell transplant (ASCT). In this paper, we present a cost analysis of various services provided to multiple myeloma patients, using either of the two modalities of treatments i.e. conventional chemotherapy or ASCT. Bottom-up costing methodology was used to collect data on all health system resources, i.e. capital or recurrent, which were used to provide various services to MM patients. Capital costs were annualized for their useful life using a discount rate of 5%. Out of pocket expenditure on treatment was also ascertained. Cost was assessed for various services, including outpatient consultation, bed day hospitalization in general ward, high dependency unit intensive care setting and bone marrow transplant unit. Unit costs were calculated from both health system and patient perspective. The overall cost per patient for ASCT (including high dose chemotherapy) and conventional chemotherapy from societal perspective was INR 395,527 (USD 6085) and INR 62,785 (USD 966) respectively. Estimates on cost from our study could be used for planning health services, and evaluating cost effectiveness of different modalities of care for multiple myeloma.

Canine Cutaneous Plasmacytosis: 21 Cases (2005-2015)

BACKGROUND

Cutaneous plasmacytosis (CP) is a syndrome of multiple cutaneous plasma cell tumors, in the absence of multiple myeloma. Although rare in both humans and dogs, treatment recommendations are usually extrapolated from multiple myeloma protocols. To date, no case series of CP have been described in the veterinary literature.

HYPOTHESIS/OBJECTIVES

To describe clinical presentation, determine treatment response rates and duration, and report overall survival of dogs with CP.

ANIMALS

Twenty-one client-owned dogs with CP.

METHODS

Medical records of 21 dogs with CP were reviewed. Diagnosis was based on histopathologic evaluation of at least 1 representative cutaneous or subcutaneous lesion in dogs with ≥3 lesions. Dogs with suspicion of multiple myeloma were excluded.

RESULTS

The most commonly affected breeds were the golden (5/21) and Labrador retriever (3/21). Fourteen of 21 dogs had >10 lesions, with some having >100. Lesions commonly were described as round, raised, pink-to-red, and variably alopecic or ulcerated. The most commonly used drug protocol was combined melphalan and prednisone, with an overall response rate (ORR) of 73.7% (14/19 dogs). Single-agent lomustine was associated with a similar ORR of 71.4% (5/7 dogs). For all treatments combined, the median progression-free interval after the first treatment was 153 days. The median survival time from the first treatment was 542 days.

CONCLUSIONS AND CLINICAL IMPORTANCE

Alkylating agents were effective in inducing remission of CP; corticosteroids, melphalan, and lomustine were the most commonly used drugs. Survival times were similar to those reported in dogs with multiple myeloma treated with alkylating agents.

Palonosetron, aprepitant, and dexamethasone for prevention of nausea and vomiting after high-dose melphalan in autologous transplantation for multiple myeloma: A phase II study

Chemotherapy-induced nausea and vomiting (CINV) is a significant side effect in multiple myeloma (MM) patients receiving high-dose melphalan treatment followed by autologous stem cell transplantation (ASCT). We evaluated the efficacy and safety of a triple antiemetic combination of palonosetron, aprepitant, and low-dose dexamethasone in 24 MM patients who received melphalan conditioning (100 mg/m² on days 1-2) before ASCT (on day 4). Intravenous palonosetron (0.75 mg on day 1), oral aprepitant (125 mg on day 1; 80 mg on days 2-4), and intravenous dexamethasone (6.6 mg on days 1-4) were administered for prevention of CINV. Complete response (no emesis and no rescue antiemetic) and complete control (no emesis, no rescue antiemetic, and no more than mild nausea) rates were 75 and 68% during the overall phase (0-120 h), while they were 88 and 86% in the acute phase (0-48 h), 75 and 68% in the delayed phase (48-120 h), and 67 and 59% in the extended phase (120-168 h), respectively. There were no serious adverse events related to the antiemetic therapy. In conclusion, the three-antiemetic regimen consisting of palonosetron, aprepitant, and dexamethasone was safe and effective for controlling CINV due to high-dose melphalan treatment, especially during the delayed phase.

Interaction of natural killer cells with neutrophils exerts a significant antitumor immunity in hematopoietic stem cell transplantation recipients

Autologous hematopoietic stem cell transplantation (HSCT) can induce a strong antitumor immunity by homeostatic proliferation (HP) of T cells and suppression of regulatory T cells following preconditioning‐induced lymphopenia. However, the role of innate immunity including natural killer (NK) cells is still not understood. Here, first, we examined whether NK cells exert an antitumor effect after syngeneic HSCT in a murine colon cancer model. Flow cytometry showed that NK cells as well as T cells rapidly proliferated after HSCT, and the frequency of mature NK cells was increased in tumor during HP. Furthermore, NK cells undergoing HP were highly activated, which contributed to substantial tumor suppression. Then, we found that a large number of neutrophils accumulated in tumor early after syngeneic HSCT. It was recently reported that neutrophil‐derived mediators modulate NK cell effector functions, and so we examined whether the neutrophils infiltrated in tumor are associated with NK cell‐mediated antitumor effect. The depletion of neutrophils significantly impaired an activation of NK cells in tumor and increased the fraction of proliferative NK cells accompanied by a decrease in NK cell survival. The results suggested that neutrophils in tumor prevent NK cells from activation‐induced cell death during HP, thus leading to a significant antitumor effect by NK cells. This study revealed a novel aspect of antitumor immunity induced by HSCT and may contribute to the development of an effective therapeutic strategy for cancer using HSCT.

Flow cytometric sensitivity and characteristics of plasma cells in patients with multiple myeloma or its precursor disease: influence of biopsy site and anticoagulation method

Flow cytometry has increasing relevance for prognosis in myeloma and precursor disease (monoclonal gammopathy of unknown significance/smoldering myeloma), yet it has been reported that plasma cell enumeration by flow varies depending on the quality of marrow aspirate and field biopsied in patchy disease. We demonstrated increased sensitivity of flow over immunohistochemistry in abnormal-plasma cell detection in monoclonal gammopathy (n = 59)/smoldering myeloma (n = 87). We prospectively evaluated treatment-na ve smoldering myeloma (n = 9)/myeloma (n = 11) patients for the percentage of abnormal plasma cells/total plasma cell compartment, plasma cell viability/infiltration and flow immunophenotype depending on anticoagulant use, biopsy site and pull sequence in uni-and-bilateral bone marrow biopsies and aspirates. We found no statistical difference regarding the percentage of abnormal plasma cells, their immunophenotype or number/distribution in marrow samples even when obtained by different sequence in aspirates, or anticoagulants (p > 0.05). Our results show that plasma cell enumeration and immunophenotyping by flow cytometry is consistent under different conditions in these populations.

Importance of achieving stringent complete response after autologous stem-cell transplantation in multiple myeloma

PURPOSE

To study the impact of achieving stringent complete response (sCR), an increasingly attainable goal, after autologous stem-cell transplantation (ASCT) in patients with multiple myeloma (MM).

PATIENTS AND METHODS

Maximal response rates were determined in 445 consecutive patients who underwent ASCT within 12 months of diagnosis of MM. The patients achieving varying degrees of complete response (CR) are the focus of our study.

RESULTS

One hundred and nine patients (25%) achieved sCR after ASCT. The median overall survival (OS) rate from the time of transplantation for patients attaining sCR was not reached (NR), in contrast to those patients achieving conventional complete response (CR; n = 37; OS, 81 months) or near CR (nCR; n = 91; OS, 60 months; P < .001). Five-year OS rates were 80%, 53%, and 47% for sCR, CR, and nCR, respectively. The median time to progression (TTP) from ASCT of patients achieving sCR was significantly longer (50 months) than TTP of patients achieving CR or nCR (20 months and 19 months, respectively). On multivariable analysis, post-ASCT response of sCR was an independent prognostic factor for survival (hazard ratio, 0.44; 95% CI, 0.25 to 0.80; versus CR; P = .008), in addition to proliferation rate, pre-ASCT cytogenetics, and performance status. OS rates of patients attaining sCR continued to remain superior at 2-year landmark (median, NR v 70 months for conventional CR group; P = .007).

CONCLUSION

Improved long-term outcome is seen after ASCT with achievement of sCR when compared with lesser degrees of responses. Myeloma trials reporting the response rates should identify patients achieving sCR and CR separately, owing to markedly disparate outcomes of the two categories.

Total marrow irradiation as part of autologous stem cell transplantation for Asian patients with multiple myeloma

To compare the outcomes of melphalan 200 mg/m² (HDM200) and 8 Gy total marrow irradiation (TMI) delivered by helical tomotherapy plus melphalan 140 mg/m² (HDM140 + TMI 8 Gy) in newly diagnosed symptomatic multiple myeloma (MM) Asian patients. Between 2007 and 2010, nine consecutive myeloma patients who were scheduled to undergo autologous stem cell transplantation (ASCT) were studied. The patients received three cycles of vincristine-adriamycin-dexamethasone (VAD) regimen as induction chemotherapy, and if they had a partial response, peripheral blood stem cells were collected by dexamethasone-etoposide-cyclophosphamide-cisplatin (DECP). In arm A, six patients received the HDM200. In arm B, three patients received HDM140 + TMI 8 Gy. In arm B, the neutropenic duration was slightly longer than in arm A (P = 0.048). However, hematologic recovery (except for neutrophils), transfusion requirement, median duration of hospitalization, and the dose of G-CSF were similar in both arms. The median duration of overall survival and event-free survival was similar in the two arms (P = 0.387). As a conditioning regiment, HDM140 + TMI 8 Gy provide another chance for MM Asian patients who were not feasible for HDM200.

Autologous transplant in multiple myeloma with an augmented conditioning protocol

We compared the tolerability and anti-myeloma effect of two conditioning regimens for autologous stem cell transplant (auto-SCT) in consecutive groups of patients. Protocol 1 was the earlier, and consisted of the combination of three agents in a sequential manner, including etoposide, thiotepa and melphalan (n = 29), while protocol 2 employed melphalan alone (n = 34). The two groups were comparable (other than younger age in protocol 1). Conditioning with protocol 1 seemed more toxic, as expressed by the higher number of febrile days and higher demand for parenteral nutrition. This was not expressed with longer admission time. With 108 and 60 months' median follow-up, respectively, the median survival in patients treated by protocol 2 (melphalan 200 mg/m(2)) was reached at 59 months, while the median survival was not yet reached in patients treated with protocol 1 (p = 0.039). The time to progression was significantly longer with protocol 1 (median 44 months vs. 17 months with protocol 2, p = 0.033). Confounded by the small number of patients, conditioning with melphalan augmented by etoposide and thiotepa in a sequential manner is slightly more toxic than melphalan alone and may benefit patients with myeloma undergoing auto-SCT.

Myeloid neoplasms secondary to plasma cell myeloma: an intrinsic predisposition or therapy-related phenomenon? A clinicopathologic study of 41 cases and correlation of cytogenetic features with treatment regimens

We describe 41 cases of myeloid neoplasms (MNs) secondary to plasma cell myeloma (PCM). The types of MN included myelodysplastic syndrome (MDS) in 34 (82.9%), acute myeloid leukemia (AML) in 4 (9.8%), and myeloproliferative neoplasm (MPN) or MDS/MPN in 3 (7.3%) cases. The latency from treatment to diagnosis of MN ranged from 9 to 384 months, with a median of 60 months. Of 37 cases with cytogenetic studies, complex abnormalities were detected in 22 (59.5%), -5(q)/-7(q) in 4 (10.8%), other abnormalities in 8 (21.6%), and normal karyotype in 3 (8.1%) cases. Complex abnormalities and -5(q)/-7(q) correlated directly with multiple chemotherapeutic regimens, particularly with combined melphalan/cyclophosphamide. Moreover, the features of cytogenetic abnormalities in our series were significantly different from those with concomitant PCM/MN who had significantly lower complex abnormalities. The latency, skewed proportion of MDS, and bias toward complex cytogenetic abnormalities/unbalanced aberrations of chromosomes 5/7 suggested an alkylating mutagenic effect on pathogenesis of secondary MN. Kaplan-Meier survival analysis demonstrated a median survival of 19 months, which was better than that for therapy-related (t)-MDS/AML. In contrast to t-MDS, the survival in our patients appeared to depend on subtypes of MDS as seen in de novo diseases.

Phase I trial of bortezomib during maintenance phase after high dose melphalan and autologous stem cell transplantation in patients with multiple myeloma

We enrolled 15 patients in this phase I dose de-escalation trial. Twelve patients are evaluable. The primary objective was to determine the safest and best tolerated maintenance dosing (MD) of bortezomib (B). The secondary endpoints were to evaluate complete response (CR), overall response (OR) and response duration. All patients receiving autologous stem cell transplant (ASCT) were eligible and registered between D+30 to D+120 after ASCT. A maximum number of 8 cycles of B was planned. Two evaluable patients in level (L) 1 received therapeutic dose of B 1.3 mg/m(2) intravenously on days (D) 1, 4, 8, and 11 in a 21 day cycle. Both these patients experienced dose limiting toxicities (DLTs). Four evaluable patients were then enrolled in dose L2 utilizing B 1.3 mg/m(2) on D 1, 4, 8, and 11 in a 28 day cycle. Two patients in L2 developed DLTs. Six evaluable patients were thereafter enrolled in L3 utilizing B 1 mg/m(2) on D 1, 8, and 15 in a 28 day cycle. Median 8 cycles of B were administered (2-8). No DLTs were observed in L3. The median duration of follow up for the entire cohort is 33 months (12-62). The median duration of response in L3 is 29.1 months (12-33). We conclude that B 1 mg/m(2) administered intravenously and may be subcutaneously on D 1, 8, and 15 in a 28 day cycle is the best tolerated MD and can be safely given beginning around D+100 post-ASCT.

Induction therapy and stem cell mobilization in patients with newly diagnosed multiple myeloma

Autologous stem cell transplantation (ASCT) is considered the standard therapy for younger patients with newly diagnosed symptomatic multiple myeloma (MM). The introduction into clinical practice of novel agents, such as the proteasome inhibitor bortezomib and the immunomodulatory derivatives (IMiDs) thalidomide and lenalidomide, has significantly contributed to major advances in MM therapy and prognosis. These novel agents are incorporated into induction regimens to enhance the depth of response before ASCT and further improve post-ASCT outcomes. Between January 2000 and November 2011, 65 patients with MM were transplanted in the Department of Biomedical Science and Clinical Oncology at the University of Bari. According to Durie-Salmon, 60 patients had stage III of disease and 5 stage II. Only 7 patients were in stage B (renal failure). Induction regimens that were administered in two or more cycles were VAD (vincristine, adriamycin, and dexamethasone), Thal-Dex (thalidomide, dexamethasone), Len-Dex (lenalidomide, dexamethasone), Vel-Dex (bortezomib, dexamethasone), VTD (bortezomib, thalidomide, and dexamethasone), and PAD (bortezomib, pegylated liposomal doxorubicin, and dexamethasone). In mobilization procedure, the patients received cyclophosphamide and granulocyte colony-stimulating factor (G-CSF). The number of cells collected through two or more leukapheresess, response after induction, and toxicity were evaluated to define the more adequate up-front induction regimen in transplantation-eligible MM patients.

New developments in conditioning regimens before auto-SCT in multiple myeloma

The current standard conditioning regimen before auto-SCT in patients with multiple myeloma is melphalan 200 mg/m(2). Several attempts have recently been made to improve this aspect of the high-dose therapy procedure. The scope of this review article is to summarize current knowledge on conditioning regimens in this setting.

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.

Post-transplant outcomes of induction therapy for myeloma: thalidomide and dexamethasone versus doxorubicin, vincristine, and dexamethasone prior to high-dose melphalan with autologous stem cell support

High-dose melphalan with autologous stem cell support improves survival as part of initial therapy for myeloma. Previous studies of pre-transplant induction regimens have compared paraprotein response rates but not long-term outcomes after transplant. We reviewed the records of all patients with multiple myeloma who received an autologous stem cell transplant at the University of Pennsylvania Medical Center. We compared outcomes for 69 patients who received high-dose melphalan conditioning after January 1, 2003 as part of initial therapy for myeloma, including 41 patients who received anthracycline-based induction (VAD or DVD) and 28 patients who received thalidomide and dexamethasone induction. Baseline characteristics in these two groups were not different, though potentially clinically important differences were apparent in assignment to post-transplant consolidation and maintenance therapy. Despite similar response rates during induction therapy, thalidomide and dexamethasone induction was associated with better progression-free survival (hazard ratio 0.18, P = 0.011) after transplant. This effect persisted in multivariable regression models including baseline characteristics and post-transplant treatment. Overall survival was not different between the two groups. These results suggest that the use of thalidomide during induction therapy may lead to improved long-term outcomes after transplant. Future trials comparing induction therapies should examine progression-free and overall survival after transplant to confirm this benefit.

Melphalan: old and new uses of a still master drug for multiple myeloma

The treatment of multiple myeloma has seen significant changes from the initial use of melphalan to the introduction of stem cell transplantation and, most recently, to the era of novel targeted agents. Melphalan still remains as a reference drug for combination regimens, including emerging newer therapeutic options, either used at a standard dose for initial or salvage treatments in patients who are not eligible for more intensive therapies, or in conjunction with new molecules within high-dose chemotherapy programs. In this review, the authors analyze old and novel regimens, including melphalan for the treatment of newly diagnosed or relapsed/resistant patients with multiple myeloma in the clinical settings of standard chemotherapy, as well as autologous or allogeneic stem cell transplantation.

Melphalan and its role in the management of patients with multiple myeloma

Melphalan is an alkylating agent approved for the treatment of multiple myeloma and ovarian cancer. The combination of oral melphalan and prednisone was first introduced in the 1960s and remains the standard therapy for elderly multiple myeloma patients. High-dose melphalan followed by autologous stem cell support became the standard treatment for younger patients since the 1990s. The occurrence of drug resistance is the major limiting factor for the long-term success of this therapy, and relapse always occurs. In recent years, advances in the understanding of the pathogenesis of myeloma and the mechanism of drug resistance have led to the development of novel targeted therapies that are able to overcome resistance and show additive or synergistic effects with melphalan. Thalidomide, its immunomodulatory derivative lenalidomide and the proteasome inhibitor bortezomib, in combination with oral melphalan in the elderly and with intravenous melphalan in younger patients, are changing the traditional treatment paradigm of multiple myeloma.

High-dose melphalan versus busulfan, cyclophosphamide, and etoposide as preparative regimens for autologous stem cell transplantation in patients with multiple myeloma

High-dose chemotherapy (HDC) with autologous stem cell transplant (ASCT) has improved response rates and survival for patients with multiple myeloma (MM). We report a single-institution experience using two conditioning regimens, busulfan, cyclophosphamide, and etoposide (BCV) or high-dose melphalan (HDM). Between July 1992 and August 2003, 110 patients with MM (median age=56.1) underwent HDC with ASCT using either BCV (n=62) or HDM (n=48) in sequential cohorts as the preparative regimen. Overall response rates, progression-free survival, and median overall survival were similar. BCV and HDM confer similar long-term outcomes with similar toxicity profiles as conditioning regimens prior to autologous stem cell transplant in patients with MM.

Serum M-spike and transplant outcome in patients with multiple myeloma

High dose therapy with autologous stem cell transplantation (HDT-ASCT) has prolonged survival in patients with multiple myeloma. Patients who achieve a complete response (CR) benefit the most from this form of therapy. Thus, achieving a CR is an important goal of therapy and it will be beneficial if the probability of achieving CR can be determined for any patient before transplant. Here we report that pretransplant monoclonal protein level (M-spike) was found to be an important predictor. Thus, we used knowledge of the rate of M-protein production by myeloma cells together with the clearance of the protein to estimate the pretransplant disease burden. We show that the pretransplant disease burden, based on the M-spike, is the only predictor for achieving CR. A simple function that describes this probability is presented. We also provide an estimate of the rate of tumor regrowth in patients who obtain a CR and in patients who only get a partial response with HDT-ASCT. The significant expansion of myeloma cells after HDT-ASCT is clearly evident. Clinical trials must be designed that take into account these kinetic aspects of the disease.

The first 2 years of clinical experience with peripheral blood stem cell transplantation for various hematological malignancies: results from a single Baskent University Center

Autologous stem cell transplantation is the current standard approach for patients with multiple myeloma and relapsed or refractory lymphoma. Nonmyeloablative allogeneic stem cell transplantation has been applied worldwide. We analyzed the results of transplantation activity from 2004 to 2006. Seven evaluable patients younger than 65 years old with stage II/III multiple myeloma were treated with high-dose melphalan therapy (140 mg/m(2)) plus autologous peripheral blood stem cell transplantation. Complete responses or tumor reductions of more than 75% were obtained in all patients. At a median follow-up of 10 months, all patients remained disease-free. Four patients with acute myeloblastic leukemia underwent nonmyeloablative allogeneic peripheral stem cell transplantation. Their median age was 30 years. One patient was refractory and the others were in hematological remission. The patients received fludarabine-based preparative regimens. All patients received fully matched blood from a related donor 2 days after chemotherapy in conjunction with graft-versus-host disease prophylaxis. One refractory patient with >90% engraftment had late autologous reconstitution at 3 months with evidence of relapse. All other patients in remission remained with >90% donor cell engraftment. These patients are disease-free at 13, 10, and 2 months. Toxicity was minimal. These results showed promise due to the minimal toxicity observed with the conditioning regimens which indicated the feasibility of these procedures.

In vivo and in silico studies on single versus multiple transplants for multiple myeloma

High-dose therapy and autologous stem cell transplantation (HDT-ASCT) have significantly improved survival in multiple myeloma (MM). However, patients are not cured, responses are variable and only about 40% of patients achieve a complete response (CR). Optimal timing of the procedure and knowledge of the relapse kinetics may assist physicians when they consider this therapeutic modality for their patients. We analyzed myeloma tumor burden and kinetics before and after HDT-ASCT in a cohort of 265 patients. Disease burden was estimated from serial M-spike measurements and the data fitted to the Gompertz function to determine the general parameters for all patients. Functions that couple disease burden and kinetics with time to progression (TTP) were derived and used to determine the optimal timing of transplantation. Patients who achieve CR with the first episode of HDT-ASCT should not be routinely offered tandem transplantation but carefully monitored and transplanted at an optimal disease burden. If CR is not achieved with a first trial of HDT-ASCT, the probability of CR after a tandem second trial is approximately 10%. TTP after tandem transplants (with its higher associated mortality) cannot be superior to TTP achieved with optimally timed serial transplants. Individualized HDT-ASCT for patients with MM is possible and may optimize results.

Risk factors for relapse after complete remission with high-dose therapy for multiple myeloma

Complete remission (CR) is an important surrogate for long-term survival for patients with multiple myeloma. However, most patients achieving CR eventually relapse and die from their disease. To better define the predictors of relapse, we conducted a retrospective review of outcomes for patients who achieved CR after autografting at our institution. From January 1990 to December 2002, among >400 patients transplanted, 81 (54 males and 27 females) achieved CR. With a median follow up of 58 months for all surviving patients, the 5-year progression-free survival (PFS) was 33% [95% confidence interval (CI) = 23 - 44] and 5-year overall survival (OS) was 67% (95% CI = 54 - 77). Median PFS was 37 months and median OS has not yet been reached. On multivariate analysis, high tumor mass at diagnosis emerged as a predictor of poor outcome. We conclude that high tumor mass at diagnosis predicts a significantly shorter remission duration for myeloma patients undergoing autografting.

Cyclophosphamide mobilization does not improve outcome in patients receiving stem cell transplantation for multiple myeloma

PURPOSE

Patients with multiple myeloma who undergo autologous stem cell transplantation (ASCT) and exhibit a complete response (CR) have a superior overall survival and time to progression (TTP). High-dose cyclophosphamide is often used before ASCT for mobilization of hematopoietic stem cells. We hypothesized that cyclophosphamide might further improve CR rates in patients undergoing ASCT. We searched the Mayo Clinic myeloma transplantation database for patients who had stem cell mobilization with hematopoietic growth factor alone or cyclophosphamide and growth factor. The impact of cyclophosphamide on CR rates and TTP was evaluated.

PATIENTS AND METHODS

A cohort of 201 patients was identified: 127 mobilized with cyclophosphamide and growth factor and 74 with growth factor alone. There were no statistically significant differences between the 2 cohorts in regard to age, sex, b2-microglobulin level, plasma cell labeling index, cytogenetics, conditioning regimen, or disease status at time of transplantation.

RESULTS

Complete response rates were 37.4% and 41.3% (P = 0.6115) for patients mobilized with cyclophosphamide combined with growth factor and growth factor alone, respectively, and TTPs were 19.9 months and 20.9 months (P = 0.59). In a multivariate analysis for TTP, cytogenetics and CR rates were the only independent variables (P = 0.0012 and P < 0.0001, respectively).

CONCLUSION

We conclude that high-dose cyclophosphamide does not increase overall CR rates or improve TTP for patients with myeloma undergoing ASCT.

High-dose idarubicin, busulphan and melphalan for autologous stem cell transplantation in multiple myeloma responsive to DAV chemotherapy: comparison with a historical control

Since 1997, 32 newly diagnosed multiple myeloma patients responsive to DAV chemotherapy were autografted with idarubicin-intensified busulphan-melphalan (ida-bu-mel). Main endpoints of the study were transplant-related toxicity, overall survival (OS) and progression-free survival (PFS). The results were compared with a historical control group of 38 patients treated with the 'standard' bu-mel regimen. Concerning time to engraftment, no significant difference was observed between the two groups, while toxicity was significantly higher in the intensive conditioning group, regarding grade IV mucositis, duration of profound neutropenia, incidence of infections and platelet requirement. Five-year OS and PFS are 73 versus 78% and 37 versus 48% for the intensive and standard regimen, respectively (p value not significant). The ida-bu-mel schedule appears to be a feasible and effective regimen for newly diagnosed multiple myeloma patients; nevertheless, no apparent benefit in OS and PFS arises from the comparison with a historical control treated with standard bu-mel, which is better tolerated and at least equally effective.

Stem-cell transplantation in multiple myeloma

In patient with newly diagnosed multiple myeloma (MM), randomized studies have shown that autologous stem-cell transplantation (ASCT) is superior to conventional chemotherapy, and ASCT is now standard care, at least for younger patients. The best conditioning regimen is melphalan 200 mg/m2, and the best stem-cell source is unselected peripheral progenitor cells. Recent results of the IFM94 trial show that double ASCT is superior to single ASCT, at least in patients who do not achieve a 90% response after one transplant. By combining biologic markers (beta2-microglobulin, albumin) and genetic markers (hypodiploidy, chromosome 13 deletion) it is possible to accurately predict prognosis after ASCT. The results of allogeneic SCT remain disappointing due to a high transplant mortality. Strategies combining ASCT and reduced-intensity allogeneic SCT are currently being studied.

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.

Cardiac toxicity of high-dose chemotherapy

Cardiac toxicity is an uncommon but potentially serious complication of high-dose (HD) chemotherapy and little is known about incidence, severity and underlying mechanisms. We have systematically reviewed the literature of the last 30 years to summarize and appraise the published evidence on cardiac toxicity associated with HD chemotherapy. HD cyclophosphamide-containing regimens have been most commonly associated with cardiac toxicity, with a progressively decreasing incidence over time. Dosage, application regimens and coadministration of other chemotherapeutic agents emerged as risk factors. While cardiac toxicity has been rarely associated with other cytotoxic drugs, an unexpected incidence of severe cardiotoxicity resulted from reduced-intensity conditioning regimens containing melphalan and fludarabine. Predictive value of cardiologic examination of patients is limited, and patients with a slight depression of cardiac performance could tolerate HD chemotherapy. Clinical examination, resting electrocardiography and dosage adjustment in overweight patients remain the mainstay of prevention, with bidimensional echocardiography (2D echo) for patients with a history of anthracycline exposure. Strategies to decrease the long-term negative impact of anthracycline administration on cardiac performance are being investigated. New 2D echo-based techniques and circulating markers of cardiac function hold promise for allowing identification of patients at high risk for and early diagnosis of cardiac toxicity.

Double autologous stem cell transplantation for multiple myeloma: a Korean single center study

BACKGROUND

Although high dose chemotherapy coupled with an autologous stem cell transplantation (ASCT) is widely accepted as effective therapy for multiple myeloma (MM), few reports are available in Korea, especially in the area of double ASCT. We present the results of an institutional retrospective study of 12 patients with MM treated by double ASCT.

METHODS

Eligible patients received induction therapy using vincristine, adriamycin, dexamethasone (VAD), and mobilization was performed using cyclophosphamide plus lenograstim. High-dose melphalan (total 200 mg/m2) was used to condition the ASCT.

RESULTS

The median interval from diagnosis to ASCT was 6 months (range, 1.8-15.3 months). The median interval between the 1st and 2nd ASCT was 4.4 months (range 2.1-48.7 months). The median follow up was 18.3 months (range 8.1-50.5 months) for the nine surviving patients. No therapy-related mortality occurred. Following induction chemotherapy, two patients experienced CR. Following double ASCT, eight patients experienced CR. The 5 year OS was 59%. The median duration of event free survival was 2.13 years (95% CI, 0.84-3.42).

CONCLUSION

Although the results of study did not demonstrate the advantage of double ASCT, this is the first report to outline the outcome of double ASCT for Korean MM patients.

A meta-analysis on data from 575 patients with multiple myeloma randomly assigned to either high-dose therapy or conventional therapy

Long-term results of high-dose therapy followed by autologous stem cell transplantation (HDT-ASCT) as the first-line treatment for patients with myeloma are still poorly reported. To gain further insight in the long-term benefits of first-line HDT-ASCT compared with conventional therapy in myeloma, we performed a meta-analysis of individual patient data. We selected randomized trials evaluating HDT-ASCT in patients with previously untreated myeloma from 1990 to 1998, all with a median follow-up of 5 years or more. Individual data of the 3 selected trials were obtained from the study authors. Outcomes were survival, treatment-related mortality, and time without symptoms of disease or toxicity of treatment (TWiST). Five hundred seventy-five patients were analyzed, including 435 deaths (104 months of median follow-up). Compared with conventional therapy and adjusting for prognostic covariates, HDT-ASCT did not significantly prolong long-term survival (stratified hazard ratio, 0.887; 95% confidence interval, 0.735-1.072). This was not modified by accounting for heterogeneity in baseline risks, in treatment of relapse, or in outcomes across trials. There was no evidence of interaction between treatment effect on survival and presentation features. In contrast, a mean gain of 14.5 months (95% confidence interval, 9.9-19.1 mo) in TWiST was observed in the HDT-ASCT group compared with conventional therapy. In conclusion, we showed only a trend toward a long-term survival benefit of HDT-ASCT over conventional therapy for first-line treatment of myeloma. However, HDT-ASCT clearly delayed time to relapse, with a resulting 14.5 months benefit in mean TWiST.

Health related quality of life in patients with multiple myeloma undergoing a double transplantation

OBJECTIVES

To investigate the subjective well-being of patients with newly diagnosed multiple myeloma who were treated in a tandem transplantation programme.

METHODS

Fifty-one patients participated in the prospective, longitudinal questionnaire study. The EORTC QLQ-C30 and the EuroQol-5D were administered 2 wk after completion of vincristine, adriamycin and dexamethason/vincristine, adriamycin and methyl prednison (VAD/VAMP) chemotherapy, both at hospital discharge after treatment with high-dose melphalan (HDM) and 1 month after this hospital discharge, at hospital admission, at the day of hospital discharge for peripheral stem cell transplantation (PSCT) and at 6 and 12 months following discharge after PSCT.

RESULTS

Overall, patients' functioning improved during treatment and follow-up, with significant decreases shortly following PSCT. Shortly after HDM and PSCT, patients reported a considerable increase in levels of soreness in the mouth (+26/+36 points on a scale ranging form 0 to 100; P < 0.01), change of taste (+23/+21 points; P < 0.05/NS), nausea/vomiting (+26/+27 points; P < 0.01/< 0.05), appetite loss (+40/+43 points; P < 0.001) and diarrhoea (+25/+36 points; P < 0.01). However, none of these symptoms persisted during follow-up.

CONCLUSION

The intensive treatment programme was subjectively being well tolerated by the majority of patients. The duration of declined quality of life after administration of HDM seemed to be short. The duration of subjective recovery after PSCT remained uncertain, but in any case was present at the 6 month follow-up. Together with the rather good results in survival, the evaluation of quality of life invites further exploration of double transplantations in multiple myeloma.

A phase I study of 153Sm-EDTMP with fixed high-dose melphalan as a peripheral blood stem cell conditioning regimen in patients with multiple myeloma

Despite response rates of 30% after high-dose chemotherapy with autologous hematopoietic stem cell transplant, patients with multiple myeloma are not cured. 153Samarium ethylenediaminetetramethylenephosphonate (153Sm-EDTMP; Quadramet) is a short-range, beta-emitting therapeutic radiopharmaceutical with avid skeletal uptake. In total, 12 patients were treated with escalating doses of 153Sm-EDTMP (N=3/group; 6, 12, 19.8, and 30 mCi/kg) and a fixed dose of melphalan (200 mg/m(2)). No dose limiting toxicity was seen. To better standardize the marrow compartment radiation dose, the study was modified such that an additional six patients were treated at a targeted absorbed radiation dose to the red marrow of 40 Gy based on a trace labeled infusion 1 week prior to the therapy. Despite rapid elimination of unbound radiopharmaceutical via kidneys and bladder, no episodes of nephrotoxicity, hemorrhagic cystitis, or delayed radiation nephritis were observed with a median follow-up of 31 months (range 8.5-44). Median times to ANC>0.5 and platelet >20 x 10(6)/l were 12 and 11 days, respectively, with no graft failures. Overall response rate was 94% including seven very good partial responses and five complete responses. Addition of 153Sm EDTMP to melphalan conditioning appears to be safe, well-tolerated and worthy of further study.

Progressive myeloma after thalidomide therapy in a patient with immature phenotype of myeloma (plasma) cells

In our experience with thalidomide treatment for refractory multiple myeloma (MM), most patients with progressive disease (PD) did not show an increase in M-protein despite the tumor burden of myeloma cells. This finding led us to suspect that proliferation of immature myeloma cells showing MPC-1(-)/CD49e(-) phenotype may be a sign of PD. We report the results of consecutive analysis of the phenotype of myeloma (plasma) cells in an MM patient with PD during treatment with thalidomide. The myeloma cells decreased by thalidomide therapy were mature (MPC-1(+)/CD49e(+)) and intermediate (MPC-1(+)/CD49e(-)) types. When the patient was in the PD state, extramedullary plasmacytoma was recognized without proliferation of myeloma cells in the bone marrow (BM). The phenotype of myeloma (plasma) cells in both of these locations was that of immature myeloma cells (MPC-1(-)/CD49e(-)), and they showed decreased intensity of CD38 expression. The level of immunoglobulin G (IgG) in serum was decreased, and myeloma (plasma) cells in BM did not increase in PD. Although these clinical features may not be specific to MM patients in PD undergoing treatment with thalidomide, we suggest that immature myeloma cells may be resistant to thalidomide.

Comparison of high-dose melphalan with a more intensive regimen of thiotepa, busulfan, and cyclophosphamide for patients with multiple myeloma

BACKGROUND

High-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) as part of the initial treatment regimen improves progression-free survival (PFS) and overall survival (OS) for patients with multiple myeloma. The optimal preparative regimen for patients with multiple myeloma has yet to be defined. In the current study, the authors compared the outcomes associated with high-dose melphalan (HDM) and a more intensive regimen of thiotepa, busulfan, and cyclophosphamide (TBC) in patients with multiple myeloma.

METHODS

One hundred eighty-six patients with newly diagnosed multiple myeloma (median age, 51 years) received HDC with ASCT for consolidation of first remission (n = 108) or for treatment of primary refractory disease (n = 78). Seventy patients had a large tumor mass at the time of diagnosis. The preparative regimen consisted of TBC for 97 patients and HDM for 89 patients. Patients in the TBC group were younger and had more advanced disease stage at diagnosis and at the time of ASCT compared with patients in the HDM group.

RESULTS

The response rates (complete response [CR] and partial response [PR]) were similar in the TBC group (overall response rate, 66%; CR rate, 17%; PR rate, 49%) and the HDM group (overall response rate, 69%; CR rate, 28%; PR rate, 41%). PFS and OS were similar in both groups. A proportional hazards regression model revealed that Durie-Salmon disease stage at diagnosis and having received three or more previous treatment regimens were the only factors that predicted PFS; the type of preparative regimen did not influence outcome.

CONCLUSIONS

The results of the current study indicate that the use of a more intensive regimen did not improve results compared with HDM in patients with multiple myeloma. HDM should continue to be considered the standard preparative regimen for patients with myeloma.