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B Barlogie

Publications and source records attributed to B Barlogie.

At least 73 records · Page 4Linked to original sources

Recent advances in the treatment of multiple myeloma.

Multiple myeloma, a clonal B-cell malignancy, accounts for 10% of all hematologic cancers. In patients with multiple myeloma, median survival is approximately 30 to 36 months with conventional therapy, but high-dose chemotherapy resulted in better outcomes in a mature randomized trial. Pamidronate and other bisphosponates, used as supportive therapy, effectively reduce the incidence of skeletal events and decrease pain. They also have a role in disease control. Ongoing trials are now addressing such issues as further intensification with tandem transplantations, timing of transplantation, and decrease of malignant cell reinfusion by positive selection. Important laboratory observations have better defined the malignant clone and its interaction with the microenvironment. These observations will be important for the treatment of myeloma in the future.

Antineoplastic Agents↗

High-dose melphalan with autotransplantation for refractory multiple myeloma: results of a Southwest Oncology Group phase II trial.

PURPOSE: To evaluate high-dose melphalan followed by autologous stem-cell transplantation in patients with refractory multiple myeloma. PATIENTS AND METHODS: Multiple myeloma patients with alkylating agent or vincristine/doxorubicin/dexamethasone-refractory disease were eligible for the phase II multi-institutional Southwest Oncology Group trial S8993. Patients up to age 70 years were enrolled between April 15, 1991, and May 1, 1996. Patients without prior stem-cell collection were primed with high-dose cyclophosphamide (HD-CTX; 6 g/m(2)) and granulocyte-macrophage colony-stimulating factor. After stem-cell procurement, patients received melphalan 200 mg/m(2) with autologous transplantation. Upon recovery from melphalan, patients were to receive interferon alfa-2b until relapse. RESULTS: Seventy-two patients were enrolled onto S8993; five were ineligible and one received no therapy. Of the 66 assessable patients, 56 patients underwent the transplant procedure; 54 were assessable for response and 56 for toxicity. The response to HD-CTX (n = 37) included three complete remissions (CRs; 8%) and five partial remissions (PR; 14%); response to melphalan (n = 54) included 16 CRs (30%) and 19 PRs (35%), for an overall CR and >/= PR (n = 66; intent-to-treat) of 27% and 58%, respectively. Toxicities included six treatment-related deaths: two during HD-CTX and four during transplantation. The median progression-free survival (PFS) and overall survival (OS) durations on an intent-to-treat basis from transplant registration was 11 months and 19 months (95% confidence interval, 14 to 29 months), respectively. The 3-year actuarial PFS and OS rates were 25% and 31%, respectively. CONCLUSION: High-dose therapy with melphalan 200 mg/m(2) is feasible with high response rates (58% overall) and an OS of 19 months in patients with refractory multiple myeloma.

Adult↗

Novel approaches in myeloma therapy.

High-dose melphalan (200 mg/m2) followed by one or more autologous peripheral blood stem cell transplantations is a safe and effective treatment regimen for multiple myeloma. This treatment regimen is as effective as standard therapy for myeloma in older (>65 years) patients and in patients with renal failure. However, advanced age (>50 years), duration of prior standard therapy (> 12 months), and a low CD34 mobilization potential (<20 x 10(6)/kg) are associated with a higher incidence of cytogenetic myelodysplasia. Future efforts directed at curing multiple myeloma should incorporate the best remission induction regimens presently available and should use consolidation/maintenance treatment (eg, idiotype/dendritic cell vaccination and dexamethasone/cyclophosphamide/etoposide/cisplatin combination chemotherapy) to enhance sustained complete remission. Other options to improve the treatment of myeloma include novel adjunctive therapies that target the myeloma cell microenvironment (eg, bisphosphonates, thalidomide, other antiangiogenesis agents) and allogeneic transplantation techniques to induce a graft-versus-myeloma effect.

Animals↗

Identification of new nonrandom translocations in multiple myeloma with multicolor spectral karyotyping.

Multicolor spectral karyotyping (SKY) was performed on bone marrow samples from 50 patients with multiple myeloma (MM) in anticipation of discovering new previously unidentified translocations. All samples showed complex karyotypes with chromosome aberrations which, in most cases, were not fully characterized by G-banding. Patients of special interest were those who showed add(14)(q32), add(8)(q24) and those whose G-banding karyotypes showed poor chromosome morphology. Three new recurring chromosome translocations not previously reported in MM were identified. Two of the translocations involve recurring aberrations at band 14q32.3, the site of the IgH locus, with different exchange partners. The most frequently recurring rearrangement was a subtle translocation at 14q32.3 designated as a t(14;16)(q32;q22 approximately 23), which was identified in six patients. A second and larger translocation at 14q32, identified in two patients, was designated as a t(9;14)(p13;q32), previously associated with Waldenstrom's macroglobulinemia and lymphoplasmacytoid lymphoma. A third translocation, identified in two patients, involved a whole-arm t(6;8)(p10;q10) translocation. The SKY technique was able to refine the designations of over 156 aberrations not fully characterized by G-banding in this study and resolved additional chromosome aberrations in every patient studied except two. The t(14;16)(q32;q22 approximately 23) identified by SKY in this study suggests this may be a frequent translocation in MM associated with complex karyotypes and disease progression. Therefore, the SKY technique provides a useful adjunct to routine G-banding and fluorescence in situ hybridization studies in the cytogenetic analysis of MM.

Chromosomes, Human, Pair 14↗

Primary myeloma cells growing in SCID-hu mice: a model for studying the biology and treatment of myeloma and its manifestations.

Progress in unraveling the biology of myeloma has suffered from lack of an in vitro or in vivo system for reproducible growth of myeloma cells and development of disease manifestations. The SCID-hu mouse harbors a human microenvironment in the form of human fetal bone. Myeloma cells from the bone marrow of 80% of patients readily grew in the human environment of SCID-hu mice. Engraftment of myeloma cells was followed by detectable human Ig levels in the murine blood. Myeloma-bearing mice had high levels of monotypic human Igs, high blood calcium levels, increased osteoclast activity, and severe resorption of the human bones. The human microenvironment was infiltrated with Epstein-Barr virus-negative monoclonal myeloma cells of the same clonality as the original myeloma cells. Active angiogenesis was apparent in areas of myeloma cell infiltration; the new endothelial cells were of human origin. We conclude that the SCID-hu mouse is a favorable host for studying the biology and therapy of myeloma and that a normal bone marrow environment can support the growth of myeloma cells.

Animals↗

Collection, tumor contamination, and engraftment kinetics of highly purified hematopoietic progenitor cells to support high dose therapy in multiple myeloma.

Unfractionated peripheral blood stem cell (PBSC) grafts contain measurable quantities of myeloma cells and are therefore a potential source of relapse posttransplantation. In contrast, fluorescence-activated cell sorting (FACS)-sorted CD34+ Thy1+ Lin- peripheral blood cells are substantially enriched for stem cell activity, yet contain virtually no clonal myeloma cells. A study was performed in patients with symptomatic myeloma, who had received 12 months or less of preceding standard chemotherapy, to evaluate the feasibility of large scale purification of primitive hematopoietic stem cells in order to study engraftment kinetics posttransplantation and the degree of tumor cell contamination of this cell population, based on polymerase chain reaction (PCR) analysis for the patient-specific complementarity-determining region III (CDR III). PBSC were mobilized with high dose cyclophosphamide and granulocyte-macrophage colony-stimulating factor (GM-CSF). A combination of elutriation and chemical lysis was used to deplete PBSC collections of monocytes, granulocytes, erythrocytes, and platelets. Subsequently, CD34+ Thy1+ Lin- progenitor cells were purified with high speed cell sorting. Of the 10 evaluable patients, nine met the required minimum criteria of >/=7.2 x 10(5) cells/kg to support tandem transplants. After high dose melphalan (200 mg/m2) eight engrafted successfully, although granulocyte (absolute neutrophil count [ANC] >0.5 x 10(9)/L, 16 days) and platelet recovery (platelets > 50 x 10(9)/L, 39 days) was substantially delayed when compared with unmanipulated PBSC grafts; one patient required infusion of a reserve graft because of lack of evidence of engraftment by day +28. Three patients proceeded to a second graft with high dose melphalan and total body irradiation; two required infusion of a reserve graft and both died of infectious complications; one showed delayed, but complete, engraftment after this myeloablative regimen. Two of the nine evaluable patients attained a clinical complete remission (CR). The grafts from three patients were tested for tumor contamination and contained no detectable clonal myeloma cells. Larger quantities of purified cells may be required to resolve the problem of delayed engraftment.

Adult↗

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

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

Antineoplastic Agents↗

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

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

Animals↗

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

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

Centromere↗

Long-term follow-up after high-dose therapy for high-risk multiple myeloma.

Between 1985 and 1990, 133 patients with advanced multiple myeloma (MM) (74% resistance; 41% resistant relapse, RR) were treated with five high-dose therapy (HDT) regimens including: melphalan < or =100 mg/m2 (MEL 100) (46 patients); MEL 100 plus GM-CSF (24 patients); MEL 140 plus autologous bone marrow transplantation (ABMT) (eight patients); MEL 140 plus TBI 850 cGy plus ABMT (37 patients); and thiotepa 750 mg/m2 (THIO 750) + TBI 850 cGy plus ABMT (18 patients). The median follow-up of alive patients as of December 1997 was 9 years. Overall, 17% experienced treatment-related mortality within 60 days (TRM) and 12% achieved stringently defined complete remission (CR) with a median duration of 16 months; four of 16 patients (25%) remain in CR at 10 years. The median durations of event-free survival (EFS)/overall survival (OS) were 6/15 months. Superior EFS/OS were noted with MEL 100 plus GM-CSF and the two TBI-containing regimens (9/24 months among 79 patients) compared to the remaining 54 patients receiving MEL < or =100 or MEL 140 plus ABMT (3/5 months) (P = 0.0001/0.0001, respectively). Multivariate regression analyses (MVA) were performed so that, despite patient heterogeneity among the five treatment groups, potentially relevant disease, host, treatment, and supportive care variables could be identified that were associated with TRM, CR, EFS and OS. TRM was higher with creatinine >2.0 mg/dl, absence of ABMT/GM-CSF support and age >50 years; CR was superior with TBI-containing regimens and < or =12 months of prior therapy; EFS and OS both were longer with B2M < or =2.5 mg/l, age < or =50 years, absence of RR and with ABMT/GM-CSF support. In the presence of >2 favorable variables (32 % of patients), median EFS/OS durations of 18/48 months were observed which progressively declined with 2 and <2 favorable parameters to 6/11 months (28% of patients) to 3/5 months (40% of patients) (P = 0.0001/0.0001). At 10 years, 10 and 20% of patients with >2 favorable variables were event-free and alive, which was also true for the 37 patients receiving MEL 140 plus TBI. To appreciate possible long-term contributions of supportive care or treatment intensity, landmark analyses performed at 1, 2, 4 and 6 months revealed virtually identical ranking orders of prognostically favorable variables to those seen pre-HDT; once supportive care was accounted for, regimen intensity with added TBI did not emerge as an independent favorable feature.

Antineoplastic Combined Chemotherapy Protocols↗

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

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

Adult↗

Anti-myeloma activity of pamidronate in vivo.

Two patients with progressive myeloma were treated with pamidronate disodium every 2-4 weeks. Pamidronate therapy resulted in a significant reduction of marrow plasmacytosis and plasma cell labelling index (PCLI), together with durable (> or = 20 months) stabilization of immunoglobulin (Ig) levels and an increase in bone mineral density in the first patient and > 50%, reduction in Ig levels and bone marrow plasmacytosis in the second. This, to our knowledge, is the first report of an anti-myeloma effect of bisphosphonates in humans and provides evidence that a therapeutic intervention largely directed at the myeloma microenvironment may alter the natural history of the disease.

Aged↗

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

PURPOSE: To compare, in the setting of tandem autotransplantations for multiple myeloma (MM), two established methods of peripheral-blood stem-cell (PBSC) procurement with chemotherapy or hematopoietic growth factor alone. PATIENTS AND METHODS: Between June 1994 and July 1995, 44 patients with MM were randomized to PBSC mobilization with either granulocyte colony-stimulating factor (G-CSF) 16 microg/kg (group 1; n = 22) or high-dose cyclophosphamide (HDCTX) 6 g/m2 plus G-CSF 5 microg/kg (group 2; n = 22). All 44 patients received melphalan 200 mg/m2 with their first autograft and 32 patients proceeded to a second transplantation. RESULTS: Group 2 required a significantly longer time interval for completion of PBSC collection than group 1 (median, 22 v 8 days; P = .0001), greater frequency of hospitalization (100% v 32%; P = .0001), and increased transfusion of platelets (86% v 18%; P = .0001) and packed RBCs (86% v 55%; P = .02). Likewise, the incidence of fever and pneumonia/sepsis were higher in group 2 (P = .02 and P = .04, respectively). Surprisingly, despite greater CD34 cell quantities infused in group 2, median recovery times of granulocytes (both > 500/microL and 2,500/microL) and platelets (both > 50,000/microL and > 100,000/microL) were similar (all P > .7). Posttransplant toxicities were also similar. CONCLUSION: Compared with HDCTX plus G-CSF, high-dose G-CSF alone is associated with lower morbidity, shorter duration of PBSC mobilization, and comparable hematopoietic recovery after transplantation, which should result in significant cost reduction. Considering the relatively limited antitumor activity of HDCTX (10% with > or = 50% tumor cytoreduction), PBSC mobilization with HDCTX should be limited to selected patients with persistent MM despite induction chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

Nervous system dysfunction in Waldenström's macroglobulinemia: response to treatment.

A patient presented with a peripheral neuropathy and was found to have Waldenstrom's macroglobulinemia with high serum titers of antibodies to myelin-associated glycoprotein. He developed parkinsonism that was poorly responsive to levodopa. He failed conventional therapy and was treated with autologous bone marrow transplantation, which resulted in improvement of the neuropathy but not his parkinsonism. Critical cytoreduction in the B-cell clone may be necessary for improvement of the neuropathy of Waldenstrom's macroglobulinemia.

Antibodies, Monoclonal↗

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

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

Antineoplastic Agents, Alkylating↗

Biologic and therapeutic determinants of bone mineral density in multiple myeloma.

The net impact of malignancy and anti-tumor therapy on bone resorption in myeloma is poorly understood because conventional skeletal radiographs are relatively insensitive for the diagnosis and monitoring of bone disease. We performed determinations of bone mineral density (BMD) at the lumbar spine, femoral neck and radial diaphysis by dual energy X ray absorptiometry (DEXA) in 168 consecutive patients with myeloma seen at our institution. Follow up studies were performed in 41 of these patients. A detailed analysis of patient and disease characteristics was performed to identify the determinants of BMD. Compared to normal age and sex matched controls, mean (+/- SE) BMD was significantly decreased at the lumbar spine (Z score -0.4 +/- 0.10) and femoral neck (Z score -1.0 +/- 0.10), but was surprisingly above normal at the radial diaphysis (Z score +0.35 +/- 0.10), a cortical bone site devoid of hematopoietic marrow, suggesting a differential bone preserving effect at this site. Lack of correlation between the BMD findings and the presence or extent of radiographically evident osteolytic lesions suggested the presence of a systemic bone disease. On multivariate analysis, duration of disease >12 months (p = 0.003) and female sex (p = 0.01) were independently associated with a lower BMD at the femoral neck/lumbar spine. On follow up DEXA (n = 41), BMD increased at > or = 1 site in 9 of 20 patients receiving bisphosphonates and in only 2 of 21 patients not receiving such therapy (p = 0.02). Similarly a decline in BMD at > or = 1 site was seen in 9 of 21 patients not receiving bisphosphonates, irrespective of the disease response status. Interval pamidronate therapy (p = 0.0007) and a low serum beta-2-microglobulin (< 2.5 mg/l) (p = 0.04) were the two most significant variables associated with an increase in BMD on multivariate analysis. These data suggest that myeloma is associated with a systemic bone disease with progressive generalized cancellous bone loss and a bone preserving effect on the radial cortical bone. The early use of bisphosphonates may improve myeloma related bone disease.

Absorptiometry, Photon↗