Retrospective Review of the Use of High-Dose Cyclophosphamide, Bortezomib, Doxorubicin, and Dexamethasone for the Treatment of Multiple Myeloma and Plasma Cell Leukemia

BACKGROUND

Multiple myeloma (MM) usually follows a clinical course leading to refractoriness and limited treatment options in advanced stages, which might need bridge therapies to either autologous stem cell transplantation or novel therapies. We report our experience with the high-dose chemotherapy mCBAD (modified cyclophosphamide, bortezomib, doxorubicin, and dexamethasone) regimen in newly diagnosed MM (NDMM), relapsed/refractory MM (RRMM), and plasma cell leukemia (PCL) patients.

PATIENTS AND METHODS

We searched our electronic records database for MM patients who received mCBAD from 2010 to 2016 for 28-day cycles of cyclophosphamide 350 mg/m² intravenously (I.V.) twice daily with mesna 400 mg/m² I.V. daily (days 1-4), bortezomib 1.3 mg/m² subcutaneously/I.V. (days 1, 4, 8, 11), doxorubicin 9 mg/m² daily continuous infusion (days 1-4), dexamethasone 40 mg orally daily (on days 1-4, 9-12, 17-20). International Myeloma Working Group (IMWG) criteria were used for response assessment and diagnosis. Descriptive statistics, Fisher exact test, χ², Wilcoxon rank sum, and Kaplan-Meier were used for statistical purposes.

RESULTS

One hundred forty patients met the inclusion criteria. A median of 2 cycles of therapy was administered. The overall response rate was 85% in patients with RRMM (n = 116) and 100% in NDMM (n = 13) and PCL (n = 11) patients. Respective median progression-free survival (mPFS) for NDMM, PCL, and RRMM were 19.61 months (95% confidence interval [CI], 5.26 to not applicable [NA]), 7.56 months (95% CI, 4.7 to NA), and 4.64 months (95% CI, 3.75-6.73). Patients with RRMM who used mCBAD as a bridge to autologous transplant (36.2%) had mPFS (11.48 months; 95% CI, 7.52-15.9 months) compared with those who did not (mPFS: 3.19 months; 95% CI, 2.4-3.75 months). Cytopenias occurred in more than 90% of patients, and febrile neutropenia was noted in 26%. All cases of treatment-related mortality (8%) occurred in patients with RRMM, except for 1 patient with PCL.

CONCLUSION

mCBAD results in high response rates in myeloma and PCL, however, with high treatment-related mortality. Its use in RRMM should be limited to patients who have immediate need for therapy without other treatment options and who have good performance status (score of 0-1) or NDMM if novel agents are not available depending on practice setting. mCBAD can be a treatment option for patients with PCL.

Electroacupuncture for thalidomide/bortezomib-induced peripheral neuropathy in multiple myeloma: a feasibility study

Background

This single-arm study evaluated feasibility, safety, and initial efficacy of electroacupuncture for thalidomide/bortezomib-induced peripheral neuropathy (PN) in cancer patients with multiple myeloma.

Methods

Patients with neuropathy ≥ grade 2 received 20 acupuncture treatments over 9 weeks.

Results

For the 19 evaluable patients, Functional Assessment of Cancer Therapy/Gynecological Oncology Group-Neurotoxicity (FACT/GOG/NTX) mean (SD) scores improved significantly between baseline and week 13 (20.8 [9.6] vs 13.2 [8.5], p = 0.0002). Moderate effect size differences began on week 4, with the largest effect size differences found at week 9 for FACT/GOG/NTX scores, worst pain in the last 24 hours, and pain severity (Cohen’s d = 1.43, 1.19, and 1.08, respectively) and continuing through week 13 (Cohen’s d = 0.86, 0.88, and 0.90, respectively). From baseline to week 13, additional significant improvements were seen as follows: postural stability (1.0 [0.6] vs 0.8 [0.4], p = 0.02); coin test (10.0 [7.4] vs 5.6 [1.9], p < 0.0001); button test (96.1 [144.4] vs 54.9 [47.3], p < 0.0001); and walking test (21.6 [10.0] vs 17.2 [7.7], p = 0.0003). No significant changes were seen with NCS.

Conclusions

Acupuncture may help patients experiencing thalidomide- or bortezomib-induced PN. Larger, randomized, clinical trials are needed.

Trial registration

ClinicalTrials.gov Identifier: NCT00891618.

Value of novel agents and intensive therapy for patients with multiple myeloma

We conducted a retrospective evaluation of response and survival for 293 patients with multiple myeloma treated since June 2000 with primary thalidomide- or bortezomib-based combinations, of whom 207 patients received intensive therapy supported by autologous blood stem cells within the first year. Survival times were calculated after a landmark of 1 year from start of therapy, so that subsequent median survival was 8.9 years for patients with CR, 4.9 years for those with PR and 0.6 year for patients with NR (P<0.001). Multivariate analyses confirmed CR or PR as the major favorable factors with less impact on prognosis for age or disease stage. Both novel agents and high-dose therapy (HDT) resulted in high frequencies of PR or CR, with early HDT useful for many patients with NR or PR in improving response status and subsequent survival.

Bortezomib in combination with thalidomide-dexamethasone for previously untreated multiple myeloma

In a previous trial among 137 previously untreated patients with multiple myeloma, the combination of thalidomide-dexamethasone induced remission in 66% of patients, including complete remission in 13%. In an attempt to induce more frequent remissions, we added bortezomib to this program. Between 7/03 and 3/06, 38 newly diagnosed patients with multiple myeloma received at least one, but no more than 3, courses of bortezomib in a dose of 1.3 mg/m(2) IV x 4; dexamethasone 20 mg/m(2) PO for 4 days beginning on days 1, 9, 17; thalidomide 100 mg PO daily increasing to a maximum of 200 mg. There was rapid onset of remission in 33 patients (87%) including 6 patients with complete remission (16%). Most side effects were preventable, but otherwise were usually mild and reversible. After a median of 4 months, 25 eligible patients received intensive therapy with high-dose melphalan supported by autologous blood stem cells, so that the myeloma was in complete remission in 14 patients (37% of all patients). The combination of bortezomib-thalidomide-dexamethasone was a highly effective primary treatment for newly diagnosed patients with multiple myeloma.

High frequencies of response after limited primary therapy for multiple myeloma

In an effort to maintain high primary response rates against multiple myeloma and without serious toxicity, we assessed 3 different bortezomib combinations in small numbers of patients, with combinations that included cyclophosphamide and lenalidomide in modest doses and for short courses. Remissions occurred in approximately 90% of patients, with rare episodes of serious drug-related adverse effects.

BACKGROUND

Recent bortezomib combinations have induced remission in approximately 90% of patients newly diagnosed, with moderate frequency of adverse effects.

PATIENTS

In an attempt to reduce adverse effects, and to prepare qualified patients for early intensification, we assessed the antimyeloma effect and toxicity of 3 different bortezomib combinations in small numbers of patients.

METHODS

With reduced doses and short durations of exposure, we combined bortezomib with (a) cyclophosphamide/dexamethasone, (b) lenalidomide/dexamethasone/liposomal doxorubicin, and (c) cyclophosphamide/dexamethasone/lenalidomide.

RESULTS

Response rates were high, with rare episodes of severe drug-related toxicity.

CONCLUSIONS

Further study of similar combinations of effective drugs given in limited doses and for short durations would be useful.

Prognostic value of serum lactate dehydrogenase in symptomatic multiple myeloma

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Background: In patients with symptomatic multiple myeloma, the clinical features, responses to treatment, and survival times vary. Well established predictors of survival include the International Staging System (ISS), cytogenetic abnormalities, and response to therapy. Long recognized has been the association of high serum lactate dehydrogenase (LDH) with advanced disease and shorter survival. We focused here on the impact of high LDH on staging and prognosis in order to guide the role of recent advances in therapy. Methods: We evaluated 1,247 patients with newly diagnosed, symptomatic myeloma from 10/74 to 7/11. Our goal was to determine the prognostic value of high LDH (>300 IU/L) in relation to ISS stage. We also compared the frequencies of anemia, hypercalcemia, and response to therapy in patients with high LDH with those of patients with Stage III disease and normal LDH values. Results: All 1,139 patients with normal LDH lived significantly longer than the 108 patients with elevated values (47 vs. 16 months, p <.01). LDH was elevated in 9% of all patients, but in 2%, 6%, and 18% of patients with ISS-I, II, and III disease, respectively. Their survival times were also significantly shorter than those of comparable patients in each stage with normal LDH (table). Among the 108 patients with high LDH, the frequencies of hemoglobin <8.5 g/dl (54 vs. 41%, p=.03), and serum calcium>11.5 mg/dl (41 vs. 27%, p<.01) were significantly higher than those of 292 patients with Stage III disease and normal LDH, and the frequency of response to therapy was less (40 vs. 62%, p<.01). Conclusions: Serum lactate dehydrogenase provides a convenient and dependable prognostic indicator in patients with multiple myeloma. An elevated LDH value indicates a poor prognosis regardless of ISS stage, confirming the report by Gkotzamanidou, Terpos, and Dimopoulos et al, and should be included in the definition of stage III disease. Such patients require rapid control of disease with sequential combinations of effective drugs and intensive therapy in order to improve their outcome. [Table: see text]

Solitary plasmacytomas: outcome and prognostic factors after definitive radiation therapy

BACKGROUND

The objective of this study was to review the outcome of patients with solitary plasmacytoma (SP) after definitive radiation therapy.

METHODS

The authors retrospectively reviewed 84 patients with SP who were diagnosed and treated at The University of Texas MD Anderson Cancer Center during 1988 to 2008. The impact of tumor anatomic site, tumor size, and the presence of serum and urinary paraprotein at diagnosis was assessed on local control, survival, and the risk of developing multiple myeloma (MM).

RESULTS

Fifty-nine patients (70%) had bone SP, and 25 patients (30%) had extramedullary SP. Serum paraprotein was present in 39 patients (46%). The median radiation dose was 45 grays (Gy) (range, 36-53.4 Gy). Local control was achieved in 77 patients (92%). Neither radiation dose nor tumor size predicted local control. The 5-year rate of progression to MM was 47% and was higher for patients with bone SP (56% vs 30% for extramedullary SP; P = .021), and patients who had serum paraprotein detected at diagnosis (60% vs 39%; P = .016). On univariate analysis, patients aged <60 years and men had higher rates of progression to MM, although the differences were not significant (P = .048 and P = .29, respectively). Multivariate analysis revealed that bone location and serum protein at diagnosis were associated statistically with progression to MM. The 5-year overall survival rate for the entire patient cohort was 78%, and no difference was observed between patients who had bone SP versus extramedullary SP (76% vs 85%, respectively; P = .274).

CONCLUSIONS

The current results indicated that definitive radiation therapy for SP can provide excellent local control. Progression to MM remains the main problem and is more common among patients with bone SP and those who have serum paraprotein detected at diagnosis.

Rapid control of previously untreated multiple myeloma with bortezomib-lenalidomide-dexamethasone (BLD)

Between April 2006 and June 2009, 34 newly diagnosed patients with multiple myeloma received one to three courses of bortezomib 1.3 mg/m(2) i.v. four times, lenalidomide 25 mg p.o. daily for 21 days and dexamethasone 20 mg/m(2) p.o. for 4 days beginning on days 1, 9 and 17 (BLD). There was rapid onset of remission in 30 patients (88%) similar to the frequency of 87% induced by a previous combination of bortezomib-thalidomide-dexamethasone (BTD). After a median of 3.6 months, 28 patients received intensive therapy with high-dose melphalan supported by autologous blood stem cells, so that the overall frequency of complete remission (CR) was 44%, similar to the frequency of 37% observed previously. Side effects due to thalidomide with previous BTD were less frequent and severe with BLD. The combination of BLD given for one or two courses was an effective primary treatment for newly diagnosed patients with multiple myeloma.

Treatment of Waldenstrom's Macroglobulinemia with Rituximab: Prognostic Factors for Response and Progression

Recent data have suggested that rituximab is an active agent for the treatment of Waldenstrom's macroglobulinemia (WM). However, the patients that are more likely to benefit have not been clearly defined. In order to address this question we evaluated 52 patients who were treated with single-agent rituximab in the context of prospective studies. Several clinical and laboratory variables were assessed for their correlation with response and time to progression. Twenty-three (44%) patients achieved a partial response after treatment with rituximab. Previously untreated and pretreated patients had the same probability for response. Higher response rates were noted in patients with serum monoclonal protein < 40 g/l, with serum albumin > or = 35 g/l and with kappa light chain. The median time to progression for all patients was 13.8 months. A multivariate analysis indicated that elevated serum monoclonal protein levels and low serum albumin were the dominant variables associated with shorter progression. Presence of two, one or none of these adverse prognostic factors was associated with time to progression of 3.6 months, 11 months and more than 40 months, respectively. We conclude that rituximab is an effective treatment modality for patients with WM. Patients with both low levels of monoclonal protein and normal albumin are the best candidates for treatment with standard dose rituximab.

High-Dose Topotecan, Melphalan and Cyclophosphamide (TMC) with Stem Cell Support: a New Regimen for the Treatment of Multiple Myeloma

The goal of this trial was to assess the toxicity and potential efficacy of high-dose topotecan, melphalan and cyclophosphamide as a preparative regimen for patients with multiple myeloma undergoing autologous stem cell transplantation. Eighteen patients were treated, 8 for first remission consolidation, 4 with relapse sensitive disease, 3 primary refractory and 3 relapsed refractory. The median age was 56 (38 - 65) and the median number of prior regimens was 3 (1 - 8). Patients received cyclophosphamide 1 g/m2/d on days -6, -5, -4; melphalan 70 mg/m2 on days -3, -2 and topotecan 3.0 to 3.5 mg/m2/d on days -6 to -2. Peripheral blood stem cells were infused on day 0. Toxicity (Bearman Toxicity Criteria) was mostly limited to grade 1 - 2 mucositis and grade 1 diarrhea. There were no transplant-related deaths. The overall response rate at 3 months post transplantation was 89% with 17% CR, 2 of those in refractory patients. The overall response rate in refractory patients was 67%. With a median follow up of 12.3 months, 89% of patients are alive. The TMC regimen is well tolerated and produces high response rates. Further evaluation of TMC to fully assess response and survival is ongoing.

Role of autologous stem cell transplant after induction therapy with bortezomib-lenolidomide or bortezomib-thalidomide in newly diagnosed multiple myeloma patients

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Background: The introduction of novel therapeutic options with bortezomib and immunomodulatory agents in the up-front management of multiple myeloma (MM) has significantly improved induction response rates. However, the role of high dose chemotherapy and autologous stem cell transplant (ASCT) after induction with these highly active agents is not known, especially in patients with only a partial response to induction therapy. Methods: We conducted a retrospective review of 95 newly diagnosed MM patients treated with induction bortezomib-lenolidomide-dexamethasone (BLD) or bortezomib-thalidomide-dexamethasone (BTD) prior to ASCT. Responses were graded according to IMWG criteria. Results: 19 patients received BLD and 76 patients received BTD. All patients were conditioned with a melphalan-based regimen. Of the 19 patients who underwent induction with BLD, complete response (CR), very good partial response (VGPR) and partial response (PR) were achieved in 2 (11%), 8 (42%) and 9 (47%) respectively for an overall response rate (ORR) of 19/19 (100%). After ASCT, CR, VGPR and PR were achieved in 9 (47%), 5 (26%) and 5 (26%) respectively for a continued ORR of 21/21 (100%). Notably, 4/8 (50%) of patients with a VGPR after induction therapy with BLD improved to a CR after ASCT. 3/9 (33%) of patients with an initial PR to BLD improved to a CR and 1/9 (11%) with a PR improved to VGPR after ASCT. Of the 76 patients who underwent induction with BTD, CR, VGPR and PR were achieved in 6 (8%), 37 (49%) and 31(41%) respectively for an ORR of 74/76 (97%). 1 patient had stable disease and 1 patient had progressive disease. After ASCT, 27/76 (36%) achieved a CR, 30/76 (39%) a VGPR and 18/76 (24%) a PR for an ORR of 75/76 (99%). Of the patients who initially had a VGPR to BTD 16/37 (43%) improved to a CR while 5/32(16%)of PR patients improved to a CR and 9/32 (28%) of PR patients improved to a VGPR. Conclusions: Of the 40 patients who only achieved a PR after induction therapy with BLD or BTD, 16 (40%) had further improvement to a CR or VGPR after ASCT. Thus there is a significant benefit of ASCT in these patients who initially demonstrate relative resistance to induction therapy with highly active regimens.

[Table: see text]

Chemotherapy for resistant and relapsing multiple myeloma

This report summarizes a broad experience in the treatment of patients with multiple myeloma resistant to standard chemotherapy. The VAD regimen has induced remissions in about 50% of relapsing patients but in only about 25% of previously unresponsive patients. In patients resistant to VAD, high-dose therapies with intravenous melphalan, a CBV combination (cyclophosphamide-BCNU-VP-16) or an EDAP regimen (VP-16 -platinum) produced responses in about 40% of patients. However, these treatments usually required autologous bone marrow or blood stem cell support and the median duration of control was only 6 months. With an even more intensive program using high-dose melphalan and total body irradiation supported by autologous bone marrow, all patients who survived the early treatment period responded for a median duration of about 1 year. Results indicated a dose-response effect of chemoradiotherapy on VAD-resistant myeloma with the potential that such intensive regimens will prolong disease-free survival time.

Updated survival analyses after prolonged follow-up of the phase 2, multicenter CREST study of bortezomib in relapsed or refractory multiple myeloma

The Clinical Response and Efficacy Study of Bortezomib in the Treatment of Relapsing Multiple Myeloma (CREST) demonstrated substantial activity with two dose levels of bortezomib (1.0 and 1.3 mg/m(2)), alone or with dexamethasone, in relapsed or refractory multiple myeloma. We present updated survival analyses after prolonged follow-up (median >5 years). One- and 5-year survival rates were 82% and 32%, respectively, in the 1.0 mg/m(2) group (n = 28), and 81% and 45%, respectively, in the 1.3 mg/m(2) group (n = 26). Notable survival, response, and time-to-progression data suggest that a bortezomib starting dose of 1.3 mg/m(2) is preferred. If bortezomib dose reduction is required, the 1.0 mg/m(2) dose still offers patients a substantial survival benefit.

Current Treatment Strategies for Multiple Myeloma

In recent years, there have been major advances in the treatment of multiple myeloma. Among previously untreated patients, different combinations of dexamethasone, lenalidomide, thalidomide, and bortezomib have produced overall response rates of 80%-90% with complete response rates of 10%-32%, and remissions are often achieved after only 2 cycles of initiating systemic therapy. Subsequent intensification with high-dose chemotherapy supported by autologous stem cell transplantation has enabled younger patients to achieve partial and complete responses with evidence of prolonged survival. Tandem autologous stem cell transplantation and reduced-intensity allogeneic stem cell transplantation are under investigation in attempts to improve outcomes. For patients unable to pursue consolidation therapy with stem cell transplantation, remissions obtained with induction therapy can often be extended with the use of maintenance systemic therapy. Despite available therapies, relapse of disease is inevitable for nearly all patients, and treatment strategies with novel agents and novel combinations of established agents are under study.

Results of a retrospective single institution analysis of targeted skeletal radiotherapy with (166)Holmium-DOTMP as conditioning regimen for autologous stem cell transplant for patients with multiple myeloma. Impact on transplant outcomes

(166)Holmium-DOTMP is a beta-emitting radiophosphonate that localizes specifically to the bone surfaces and can deliver high-dose radiation to the bone marrow. Phase I/II trials showed feasibility and tolerability when combined with high-dose melphalan with or without total-body irradiation (TBI) in patients with multiple myeloma (MM) undergoing autologous stem cell transplantation (ASCT). The purpose of this study was to define the potential impact of (166)Holmium-DOTMP on outcomes in patients with MM undergoing ASCT. Retrospective review of transplant outcomes among patients with MM who received an ASCT between January 1998 to December 2001 with either melphalan 200 mg/m(2) or a (166)Holmium-DOTMP containing regimen as part of their initial therapy. Univariate analysis was performed for response, overall survival (OS), and event free survival (EFS). One hundred four patients were identified, of which 41 received a (166)Holmium-DOTMP containing regimen and 63 received melphalan alone. The (166)Holmium-DOTMP patients were divided into 2 groups according to the dose received (<2400 mCi versus > or = 2400 mCi). The (166)Holmium-DOTMP group had a trend towards a higher complete remission (CR) rate compared to patients receiving melphalan alone (51% versus 32%). The median EFS for the low-dose (166)Holmium-DOTMP, the high-dose (166)Holmium-DOTMP, and melphalan alone was 30, 23, and 19 months, respectively; the OS rate at 5 years for the 3 groups was 61%, 40%, and 43%, respectively. (166)Holmium-DOTMP, in combination with high-dose melphalan, can result in higher CR rates when given in optimal doses (<2400 mCi) when compared to melphalan alone, and should be further tested in phase III trials in patients with MM undergoing ASCT.

International uniform response criteria for multiple myeloma

New uniform response criteria are required to adequately assess clinical outcomes in myeloma. The European Group for Blood and Bone Marrow Transplant/International Bone Marrow Transplant Registry criteria have been expanded, clarified and updated to provide a new comprehensive evaluation system. Categories for stringent complete response and very good partial response are added. The serum free light-chain assay is included to allow evaluation of patients with oligo-secretory disease. Inconsistencies in prior criteria are clarified making confirmation of response and disease progression easier to perform. Emphasis is placed upon time to event and duration of response as critical end points. The requirements necessary to use overall survival duration as the ultimate end point are discussed. It is anticipated that the International Response Criteria for multiple myeloma will be widely used in future clinical trials of myeloma.

Percutaneous vertebroplasty and/or kyphoplasty is an effective and safe treatment for painful vertebral compression fractures in multiple myeloma (MM)

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Background: Painful vertebral compression fractures are a major source of morbidity in MM. Vertebroplasty involves percutaneous injection of polymethylmethacrylate (PMMA) into a vertebral body, while kyphoplasty involves inflation of a balloon for painful kyphotic deformity prior to stabilization with PMMA. Methods: We assessed safety and efficacy of 100 vertebroplasties and/or kyphoplasties in 81 consecutive myeloma patients between 12/2000 and 2/2005. Results: Median age was 63 (range 32–84), with 29% having prior radiotherapy to the vertebra treated. Contraindications included epidural compression of neural elements and failure to localize a symptomatic level. Kyphoplasty was preferred if kyphosis of > 20 degrees contributed to pain, or if the posterior vertebral cortex was disrupted so that controlled delivery of bone cement was difficult. Vertebroplasty was performed when vertebral collapse was either slight or so severe that insertion of balloon device was not possible, or if patient could not tolerate the general anesthesia required for kyphoplasty. The median preoperative visual analog pain score (0–10) was 8(range 2–10); the median postoperative pain score was 3 (range 0–10) (p < 0.01). There were no significant complications . Conclusions: Percutaneous vertebroplasty and kyphoplasty provided rapid and marked pain relief. These procedures are safe and feasible and represent the treatment of choice in selected MM patients with severe refractory pain due to pathologic compression fractures.

No significant financial relationships to disclose.

Frequency, characteristics, and reversibility of peripheral neuropathy during treatment of advanced multiple myeloma with bortezomib

PURPOSE

To determine the frequency, characteristics, and reversibility of peripheral neuropathy from bortezomib treatment of advanced multiple myeloma.

PATIENTS AND METHODS

Peripheral neuropathy was assessed in two phase II studies in 256 patients with relapsed and/or refractory myeloma treated with bortezomib 1.0 or 1.3 mg/m2 intravenous bolus on days 1, 4, 8, and 11, every 21 days, for up to eight cycles. Peripheral neuropathy was evaluated at baseline, during the study, and after the study by patient-reported symptoms using the Functional Assessment of Cancer Therapy Scale/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) questionnaire and neurologic examination. During the study, peripheral neuropathy was also evaluated by investigator assessment. A subset of patients underwent nerve conduction studies (n = 13).

RESULTS

Before treatment, 194 (81%) of 239 patients had peripheral neuropathy by FACT/GOG-Ntx questionnaire, and 203 (83%) of 244 patients had peripheral neuropathy by neurologic examination. Treatment-emergent neuropathy was reported in 35% of patients, including 37% (84 of 228 patients) receiving bortezomib 1.3 mg/m2 and 21% (six of 28 patients) receiving bortezomib 1.0 mg/m2. Grade 1 or 2, 3, and 4 neuropathy occurred in 22%, 13%, and 0.4% of patients, respectively. The incidence of grade > or = 3 neuropathy was higher among patients with baseline neuropathy by FACT/GOG-Ntx questionnaire compared with patients without baseline neuropathy (14% v 4%, respectively). In all 256 patients, neuropathy led to dose reduction in 12% and discontinuation in 5%. Of 35 patients with neuropathy > or = grade 3 and/or requiring discontinuation, resolution to baseline or improvement occurred in 71%.

CONCLUSION

Bortezomib-associated peripheral neuropathy seemed reversible in the majority of patients after dose reduction or discontinuation. Although severe neuropathy was more frequent in the presence of baseline neuropathy, the overall occurrence was independent of baseline neuropathy or type of prior therapy.

Safety of prolonged therapy with bortezomib in relapsed or refractory multiple myeloma

BACKGROUND

Bortezomib, a first-in-class proteasome inhibitor, is active with manageable toxicities in relapsed and/or refractory myeloma.

METHODS

Bortezomib 1.0 or 1.3 mg/m2 was administered Days 1, 4, 8, and 11 every 21 days for up to 8 cycles to patients with relapsed and/or refractory myeloma participating in two Phase II trials. Dexamethasone could be added because of progressive disease after 2 cycles or stable disease after 4 cycles. Continuation of or retreatment with bortezomib was offered to patients who, in the investigator's opinion, would benefit from extended treatment.

RESULTS

Sixty-three patients with relapsed/refractory myeloma treated in this extension trial received a median of 7 additional cycles of therapy, for a total of 14 cycles (range, 7-32) over a median duration of therapy of 45.1 weeks in the parent and extension studies. Seventy-eight percent of patients completed this study at the same or higher bortezomib dose than they started on during this study, and the treatment schedule of twice-weekly administration remained unchanged in 89%. Overall, 75% of patients received dexamethasone in combination with bortezomib for a median of 5 cycles starting either in the parent or extension study. The safety profile was similar between the extension and parent trials, with no evidence of new cumulative toxicity. The most commonly reported Grade 3/4 toxicities were thrombocytopenia (29%), with a consistent pattern of recovery during the rest period of each cycle, diarrhea (11%), anemia (11%), and neutropenia (10%). Neuropathy was reported less frequently.

CONCLUSIONS

Retreatment with or continuation of bortezomib +/- dexamethasone beyond 6 months was safe, and toxicities were manageable, in patients with relapsed and/or refractory myeloma.

Atiprimod blocks STAT3 phosphorylation and induces apoptosis in multiple myeloma cells

Multiple myeloma (MM) accounts for 1 % of all cancer deaths. Although treated aggressively, almost all myelomas eventually recur and become resistant to treatment. Atiprimod (2-(3-Diethylaminopropyl)-8,8-dipropyl-2-azaspiro[4,5] decane dimaleate) has exerted anti-inflammatory activities and inhibited oeteoclast-induced bone resorption in animal models and been well tolerated in patients with rheumatoid arthritis in phase I clinical trials. Therefore, we investigated its activity in MM cells and its mechanism of action. We found that Atiprimod inhibited proliferation of the myeloma cell lines U266-B1, OCI-MY5, MM-1, and MM-1R in a time- and dose-dependent manner. Atiprimod blocked U266-B1 myeloma cells in the G₀/G₁ phase, preventing cell cycle progression. Furthermore, Atiprimod inhibited signal transducer and activator of transcription (STAT) 3 activation, blocking the signalling pathway of interleukin-6, which contributes to myeloma cell proliferation and survival, and downregulated the antiapoptotic proteins Bcl-2, Bcl-X_L, and Mcl-1. Incubation of U266-B1 myeloma cells with Atiprimod induced apoptosis through the activation of caspase 3 and subsequent cleavage of the DNA repair enzyme poly(adenosine diphosphate-ribose) polymerase. Finally, Atiprimod suppressed myeloma colony-forming cell proliferation in fresh marrow cells from five patients with newly diagnosed MM in a dose-dependent fashion. These data suggest that Atiprimod has a role in future therapies for MM.

Prognostic significance of magnetic resonance imaging of bone marrow in previously untreated patients with multiple myeloma

BACKGROUND

Magnetic resonance imaging (MRI) has been a useful technique for the assessment of patients with multiple myeloma (MM). We evaluated the prognostic significance of different MRI patterns in symptomatic patients with MM.

PATIENTS AND METHODS

A total of 142 symptomatic MM patients underwent MRI before treatment. MRI patterns of involvement were correlated with known prognostic variables, including the International Staging System (ISS), response to treatment and survival.

RESULTS

Focal marrow lesions were identified in 50% of patients, diffuse marrow replacement in 28%, a variegated pattern in 14% and normal pattern in 8%. When patients with the diffuse pattern were compared with patients with the other MRI patterns, they had features of more advanced disease such as higher ISS, anemia, hypercalcemia, elevated lactate dehydrogenase and extensive marrow plasmacytosis. Response rate was similar among patients with different MRI patterns. Median survival was 24 months for patients with the diffuse pattern, 51 months for those with the focal pattern, 52 months for those with the variegated pattern and 56 months for patients with the normal pattern (P = 0.001). The presence or absence of a diffuse MRI pattern separated patients with ISS stages I and II into two subgroups with significantly different survival times of 28 months and 61 months, respectively (P = 0.01). Furthermore, a diffuse MRI pattern predicted inferior outcome regardless of whether or not patients had received high-dose therapy with autologous stem cell transplantation.

CONCLUSION

Diffuse marrow replacement on MRI adds to the evaluation of patients with multiple myeloma and their management.

Thalidomide-dexamethasone as primary therapy for advanced multiple myeloma

The value of thalidomide-dexamethasone was assessed in 26 consecutive, previously untreated patients with multiple myeloma of high tumor mass. All showed Hgb < 8.5 g/dL, serum calcium > 11.5 mg/dL, or both. The response rate was 73%, frequency of early death < 3 months was 5%, projected median survival was 30 months, and projected median remission time was 25 months. There were no occurrences of grade 3 or 4 neutropenia or thrombocytopenia, so that serious infection occurred in only 12% of patients. Thalidomide-dexamethasone was useful for these patients with advanced disease because of the high response rate and acceptable survival, with a low frequency of serious complications.

How we treat Waldenström's macroglobulinemia

Waldenström's macroglobulinemia (WM) is a lymphoplasmacytic lymphoma which produces monoclonal immunoglobulin M (IgM). Over the last decade, new treatment modalites have been developed for the management of this disorder. Our objective is to provide treatment recommendations for WM. A review of published reports was facilitated by a MEDLINE computer search and by a manual search of Index Medicus. Other sources included abstracts and conference proceedings. Most patients with WM who are diagnosed by chance without symptoms should not be treated. Initiation of treatment should not be based on level of serum monoclonal protein per se. The presence of cytopenia, significant adenopathy or organomegaly, symptomatic hyperviscosity, severe neuropathy or cryoglobulinemia indicates the need for treatment. The main choices for primary treatment of symptomatic patients with WM include alkylating agents, the nucleoside analogs fludarabine or cladribine and the monoclonal antibody rituximab or combinations of these programs. There are no data from prospective randomized studies to recommend the use of one program over another. Nevertheless, the need for rapid disease control may favor the use of nucleoside analogs, whereas the presence of significant cytopenia may favor rituximab. High dose therapy with autologous stem cell transplantation may induce responses even in patients with resistance to all three class of agents. It may be prudent to avoid nucleoside analogs in patients who are candidates for high dose therapy. Despite the lack of randomized trials, a rational approach to the treatment of patients with WM is possible. Several factors, including the presence of cytopenias, need for rapid disease control, candidacy for autologous stem cell transplantation, age and co-morbid conditions, should be taken into consideration when choosing the most appropriate primary treatment.

Bortezomib in recurrent and/or refractory multiple myeloma

BACKGROUND

Bortezomib is a potent, reversible proteasome inhibitor that has been approved for the treatment of recurrent and/or refractory multiple myeloma, but its activity in patients with renal impairment has not been studied to date.

METHODS

Response rates, safety, and 20S proteasome activity were assessed in relation to baseline creatinine clearance (CrCl) among patients with recurrent and/or refractory myeloma (n = 256 patients) who were treated with bortezomib in 2 Phase II trials. Bortezomib was administered by intravenous bolus on Days 1, 4, 8, and 11 of a 21-day cycle at 2 doses, 1.0 mg/m2 (n = 28 patients) and 1.3 mg/m2 (n = 228 patients).

RESULTS

Of 10 patients with CrCl < or = 30 mL/minute, 7 patients completed the protocol-specified 8 cycles of treatment; 4 patients received the 1.3 mg/m2 bortezomib dose, and 3 patients received the 1.0 mg/m2 bortezomib dose. Using the European Group for Blood and Marrow Transplantation criteria, responses were assigned by an independent committee to 3 of the 10 patients (2 partial responses and 1 minimal response), a response rate similar to that of the overall treated population. Patients with CrCl > 80 mL/minute (n = 105 patients), 51-80 mL/minute (n = 99 patients), and < or = 50 mL/minute (n = 52 patients) had similar rates of discontinuation and similar adverse event profiles. Renal function did not appear to affect the 1-hour postdose proteasome inhibition or its recovery.

CONCLUSIONS

Clinical experience in a limited number of patients with impaired renal function suggests that bortezomib provides clinical benefit with manageable toxicities in this high-risk population.

A phase 2 study of two doses of bortezomib in relapsed or refractory myeloma

In a phase 2 open-label study of the novel proteasome inhibitor bortezomib, 54 patients with multiple myeloma who had relapsed after or were refractory to frontline therapy were randomized to receive intravenous 1.0 or 1.3 mg/m(2) bortezomib twice weekly for 2 weeks, every 3 weeks for a maximum of eight cycles. Dexamethasone was permitted in patients with progressive or stable disease after two or four cycles respectively. Responses were determined using modified European Group for Blood and Marrow Transplantation criteria. The complete response (CR) + partial response (PR) rate for bortezomib alone was 30% [90% confidence interval (CI), 15.7-47.1] and 38% (90% CI, 22.6-56.4) in the 1.0 mg/m(2) (8 of 27 patients) and 1.3 mg/m(2) (10 of 26 patients) groups respectively. The CR + PR rate for patients who received bortezomib alone or in combination with dexamethasone was 37% and 50% for the 1.0 and 1.3 mg/m(2) cohorts respectively. The most common grade 3 adverse events were thrombocytopenia (24%), neutropenia (17%), lymphopenia (11%) and peripheral neuropathy (9%). Grade 4 events were observed in 9% (five of 54 patients). Bortezomib alone or in combination with dexamethasone demonstrated therapeutic activity in patients with multiple myeloma who relapsed after frontline therapy.

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.

Clinical outcomes with intensive therapy for patients with primary resistant multiple myeloma

Clinical outcomes were evaluated in 89 consecutive patients with multiple myeloma that had not responded to dexamethasone-based primary therapy, who received early intensive therapy supported by autologous stem cell transplantation. Results were compared with those of 45 comparable patients who refused or were unable to receive intensive treatment for socioeconomic reasons. Following high-dose therapy, the response rate was 69% including 16% with CR. Survival of 14 patients with CR (median >7.0 years) was significantly longer than those of 47 patients with PR (median 4.5 years) or of 28 patients who remained NR (median 2.2 years). CR occurred in 43% of patients with serum myeloma protein <1.5 gm/dl, in contrast to 7% of those with higher values, a finding similar to that observed previously for patients consolidated in PR. No prognostic factor was associated with PR and, in view of the high frequencies of PR or CR, all patients with primary resistant myeloma should be considered for early intensive therapy. The limited improvement of lifespan and disease-free survival for those in PR indicated the need for further treatment to achieve CR, the major surrogate marker for long survival.

Outcomes of autologous stem cell transplantation in patients with multiple myeloma who received dexamethasone-based nonmyelosuppressive induction therapy

High-dose chemotherapy (HDC) followed by autologous stem cell transplantation (ASCT) improves survival in myeloma (MM). The role of induction therapy on outcomes of ASCT in MM has not been systematically studied. Nonmyelosuppressive (NMS) steroid-based induction can be used in MM, with the potential of reducing neutropenias and other toxic effects prior to ASCT. NMS induction however could be associated with poorer outcomes if disease control or stem cell collection were inadequate. We studied outcomes of 136 MM patients who underwent HDC and ASCT as part of their initial therapy between March 1998 and December 2000. Of these, 46 received HDC and ASCT without any exposure to myelosuppressive agents, 39 received myelosuppressive therapy for disease control and/or stem cell collection, and 51 received alkylating agent-based initial treatment. We compared OS and EFS rates, stem cell collectability, and contamination of the grafts with monoclonal plasma cells. After a median of 33 months, response rates, EFS and OS rates were comparable in the three groups of patients. Adequacy of stem cell collection and plasma cell contamination were similar. Our data support the hypothesis that NMS induction for patients with MM is safe and effective and does not compromise the results of HDC.

Nuclear factor-kappaB and STAT3 are constitutively active in CD138+ cells derived from multiple myeloma patients, and suppression of these transcription factors leads to apoptosis

Chemoresistance is a major problem in the treatment of patients with multiple myeloma (MM). Because of the central role of the nuclear transcription factors nuclear factor-kappaB (NF-kappaB) and signal transducer and activator of transcription 3 (STAT3) in chemoresistance, cell survival, and proliferation, we investigated whether MM cells derived from patients express activated NF-kappaB and STAT3 and if their suppression induces apoptosis. We assayed CD138+ cells from the bone marrow of 22 MM patients and checked for the activated forms of NF-kappaB and STAT3 by immunocytochemistry. We found that MM cells from all the patients expressed the activated forms of NF-kappaB and STAT3 but to a variable degree (NF-kappaB: low, 3 of 22; moderate, 5 of 22; or high, 14 of 22; STAT3: none, 1 of 22; low, 3 of 22; moderate, 5 of 22; or high, 14 of 22). Constitutive activation of NF-kappaB was in some cases also independently confirmed by electrophoretic mobility gel shift assay. In contrast to MM patients, activated forms of NF-kappaB and STAT3 were absent in cells from healthy individuals. Suppression of NF-kappaB and STAT3 activation in MM cells by ex vivo treatment with curcumin (diferuloylmethane) resulted in a decrease in adhesion to bone marrow stromal cells, cytokine secretion, and in the viability of cells. When compared with curcumin, dexamethasone was less effective in suppression of NF-kappaB activation and induction of apoptosis in myeloma cells. Overall, our results indicate that fresh cells from MM patients express constitutively active NF-kappaB and STAT3, and suppression of these transcription factors inhibits the survival of the cells.

Thalidomide with or without dexamethasone for refractory or relapsing multiple myeloma

Both thalidomide and intermittent high-dose dexamethasone are agents with established activity against multiple myeloma. We summarized our experience with thalidomide alone, and then in combination with dexamethasone, for groups of patients with myeloma resistant or relapsing despite standard treatments. Criteria of response were based on greater than 50% reduction of serum myeloma protein and/or greater than 75% reduction of Bence Jones protein for patients treated with thalidomide alone and greater than 75% reduction of serum myeloma protein and/or greater than 90% reduction of Bence Jones protein for those who received thalidomide with dexamethasone. Among patients with resistant or relapsing disease treated with a combination of thalidomide and dexamethasone, 47% of patients achieved remission with significant prolongation of survival for responsive patients. Among patients in stable partial remission after intensive therapy who received the same program, myeloma protein was reduced further by greater than 90% in 52% of patients who had not received prior thalidomide/dexamethasone. Side effects were frequent, mild and reversible, and often preventable. Our program of thalidomide/dexamethasone was a safe and effective combination for patients with resistant or relapsing disease, or as consolidation of partial remission after intensive therapy.

166Ho-DOTMP plus melphalan followed by peripheral blood stem cell transplantation in patients with multiple myeloma: results of two phase 1/2 trials

Holmium-166 1, 4, 7, 10-tetraazcyclododecane-1, 4, 7, 10-tetramethylenephosphonate (166Ho-DOTMP) is a radiotherapeutic that localizes specifically to the skeleton and can deliver high-dose radiation to the bone and bone marrow. In patients with multiple myeloma undergoing autologous hematopoietic stem cell transplantation two phase 1/2 dose-escalation studies of high-dose 166Ho-DOTMP plus melphalan were conducted. Patients received a 30 mCi (1.110 Gbq) tracer dose of 166Ho-DOTMP to assess skeletal uptake and to calculate a patient-specific therapeutic dose to deliver a nominal radiation dose of 20, 30, or 40 Gy to the bone marrow. A total of 83 patients received a therapeutic dose of 166Ho-DOTMP followed by autologous hematopoietic stem cell transplantation 6 to 10 days later. Of the patients, 81 had rapid and sustained hematologic recovery, and 2 died from infection before day 60. No grades 3 to 4 nonhematologic toxicities were reported within the first 60 days. There were 27 patients who experienced grades 2 to 3 hemorrhagic cystitis, only 1 of whom had received continuous bladder irrigation. There were 7 patients who experienced complications considered to be caused by severe thrombotic microangiopathy (TMA). No cases of severe TMA were reported in patients receiving in 166Ho-DOMTP doses lower than 30 Gy. Approximately 30% of patients experienced grades 2 to 4 renal toxicity, usually at doses targeting more than 40 Gy to the bone marrow. Complete remission was achieved in 29 (35%) of evaluable patients. With a minimum follow-up of 23 months, the median survival had not been reached and the median event-free survival was 22 months. 166Ho-DOTMP is a promising therapy for patients with multiple myeloma and merits further evaluation.

A phase 2 study of bortezomib in relapsed, refractory myeloma

BACKGROUND

Bortezomib, a boronic acid dipeptide, is a novel proteasome inhibitor that has been shown in preclinical and phase 1 studies to have antimyeloma activity.

METHODS

In this multicenter, open-label, nonrandomized, phase 2 trial, we enrolled 202 patients with relapsed myeloma that was refractory to the therapy they had received most recently. Patients received 1.3 mg of bortezomib per square meter of body-surface area twice weekly for 2 weeks, followed by 1 week without treatment, for up to eight cycles (24 weeks). In patients with a suboptimal response, oral dexamethasone (20 mg daily, on the day of and the day after bortezomib administration) was added to the regimen. The response was evaluated according to the criteria of the European Group for Blood and Marrow Transplantation and confirmed by an independent review committee.

RESULTS

Of 193 patients who could be evaluated, 92 percent had been treated with three or more of the major classes of agents for myeloma, and in 91 percent, the myeloma was refractory to the therapy received most recently. The rate of response to bortezomib was 35 percent, and those with a response included 7 patients in whom myeloma protein became undetectable and 12 in whom myeloma protein was detectable only by immunofixation. The median overall survival was 16 months, with a median duration of response of 12 months. Grade 3 adverse events included thrombocytopenia (in 28 percent of patients), fatigue (in 12 percent), peripheral neuropathy (in 12 percent), and neutropenia (in 11 percent). Grade 4 events occurred in 14 percent of patients.

CONCLUSIONS

Bortezomib, a member of a new class of anticancer drugs, is active in patients with relapsed multiple myeloma that is refractory to conventional chemotherapy.

Thalidomide and dexamethasone for resistant multiple myeloma

Between November 1998 and April 2000, the combination of thalidomide and dexamethasone was evaluated in 47 consecutive patients with multiple myeloma that was resistant to prior high-dose dexamethasone-based therapies. Remission was observed in 22 patients (47%), including six patients with complete remission. Side-effects were frequent, mild and usually reversible, but deep vein thrombosis occurred in 8% of patients. Survival and remission times were longer among patients treated for previous resistant disease rather than for resistant relapse. This experience supports the use of thalidomide-dexamethasone in myeloma patients with resistant disease and justifies further trials in newly diagnosed patients.

Prognostic markers and criteria to initiate therapy in Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia

This presentation represents consensus recommendations on prognostic markers and criteria to initiate therapy in patients with Waldenstrom's macroglobulinemia (WM), which were prepared in conjunction with the Second International Workshop held in Athens, Greece during September 2002. The panel recommended that initiation of therapy should not be based on the IgM level per se since this may not correlate with the clinical manifestations of WM. The consensus panel agreed that initiation of therapy was appropriate for patients with constitutional symptoms such as recurrent fever, night sweats, fatigue due to anemia, or weight loss. The presence of progressive, symptomatic lymphadenopathy or splenomegaly provide additional reasons to begin therapy. The presence of anemia with a hemoglobin value of <or= 10 g/dL or a platelet count < 100 x 10(9)/L due to marrow infiltration also justifies treatment. Certain complications such as hyperviscosity syndrome, symptomatic sensorimotor peripheral neuropathy, systemic amyloidosis, renal insufficiency, or symptomatic cryoglobulinemia may also be indications for therapy. Recommendations for follow-up of watch-and-wait patients are that those with monoclonal gammopathy of undetermined significance (MGUS) should have serum protein electrophoresis repeated each year. Patients with asymptomatic (smoldering) macroglobulinemia should be evaluated every 6 months. Regarding prognostic markers, hemoglobin and beta(2)-microglobulin levels at diagnosis are important prognostic markers in WM: they influence the timing of treatment and survival. Age is a consistently important prognostic factor for survival. However, the panel felt that current data are inadequate to support the use of any prognostic marker to select the timing and type of therapy, and called for studies on the application of prognostic markers in WM.

2-Chlorodeoxyadenosine alone and in combination for previously untreated Waldenstrom's macroglobulinemia

Treatment for Waldenstrom's macroglobulinemia (WM) has usually been reserved for symptomatic patients and has included alkylating agent-steroid combinations and, more recently, nucleoside analogues. We now describe our experience with 2-chlorodeoxyadenosine (2-CdA) alone and in combination at our center. We treated 90 consecutive, previously untreated patients with symptomatic WM using either 2-CdA alone or in combination with other agents including prednisone (pred), cyclophosphamide (Cy), and rituximab (Rit) as follows: January 1991 to December 1992- 2-CdA 0.1 mg/kg by continuous infusion (CI) over 24 hours for days (16 patients); December 1992 to December 1995-2-CdA 0.1 mg/kg CI over 24 hours for 7 days plus pred 60 mg/m(2) orally daily for 7 days (20 patients); July 1996 to March 1998-2-CdA 1.5 mg/m(2) by subcutaneous injection (SC) every 8 hours for 7 days plus Cy 40 mg/m(2) orally twice daily for 7 days (37 patients); August 1999 to December 2001-2-CdA 1.5 mg/m(2) SC every 8 hours for 7 days plus Cy 40 mg/m(2) orally twice daily for 7 days plus Rit 375 mg/m(2) by intravenous infusion (IV) weekly for 4 weeks (17 patients). For nearly all patients, a second course was repeated after at least 6 weeks. Responding patients were monitored without further treatment until relapse. Overall response (complete [CR] + partial response [PR]) was 94% for 2-CdA alone, 60% for 2-CdA/pred, 84% for 2-CdA/Cy, and 94% for 2-CdA/Cy/Rit. Median overall survival is 73 months for 2-CdA, 41 months for 2-CdA/pred, and has not been reached for 2-CdA/Cy or 2-CdA/Cy/Rit. Cause-specific survival for 2-CdA/pred is 78 months and has not been reached for all other programs. The only poor prognostic factor for cause-specific survival was hemoglobin < 9 g/dL. 2-CdA regimens provide excellent response rates and improve cause-specific survival, with minimal treatment and little toxicity. These observations support the potential role of 2-CdA regimens as the treatment of choice for previously untreated WM.

Asymptomatic Waldenstrom's macroglobulinemia

A study was undertaken to evaluate the frequency and natural history of disease in patients with asymptomatic Waldenstrom's macroglobulinemia (WM). Among 132 consecutive, newly diagnosed patients with monoclonal IgM, 82 (27%) had symptomatic WM indicated by anemia, lymphadenopathy, or splenomegaly. Thirty-one patients had similar clinical features but were asymptomatic and followed without therapy until disease progression. There were 19 patients with monoclonal gammopathy of undetermined significance of IgM type (MGUS). In comparison to overt WM, patients with asymptomatic WM had significantly higher hemoglobin (Hgb) level (median, 12.1 v 9.7 g/dL), lower serum beta(2)-microglobulin (B(2)M) level (median, 2.4 v 3.4 mg/L), and similar IgM peaks (median, 2.2 and 1.8 g/dL). The IgM component was 3.6 g/dL or less in all patients with asymptomatic disease. For asymptomatic WM, median time to disease progression was 6.9 years with rare morbidity. Prognostic factors for early progression were Hgb <11.5 g/dL, B(2)M >or= 3.0 mg/L, and IgM peak >3.0 g/dL. Combinations of these variables defined three risk groups for progression with markedly different median times to progression of >5 years, 2 years, and 0.5 year, respectively. Response rate and survival after institution of treatment were similar to those of patients treated promptly for overt disease. We conclude that, among patients with WM, 27% were asymptomatic with slow disease progression before the need for chemotherapy. Since disease outcomes after treatment were similar to those of patients treated at diagnosis, patients with asymptomatic disease should be identified and followed without treatment for as long as risks of complications remain low.

Thalidomide alone or with dexamethasone for previously untreated multiple myeloma

PURPOSE

To evaluate the activity of thalidomide in patients with asymptomatic multiple myeloma and of thalidomide-dexamethasone in patients with previously untreated symptomatic myeloma.

PATIENTS AND METHODS

Twenty-eight patients with previously untreated asymptomatic myeloma were treated with thalidomide 100 to 200 mg orally (PO) at bedtime (qhs) with serial increments of 50 to 100 mg at weekly intervals, as tolerated to a maximum of 600 mg PO qhs. Forty consecutive previously untreated patients with symptomatic myeloma were also treated as above (maximum dose 400 mg) and received dexamethasone 20 mg/m(2) for 4 days beginning on days 1, 9, and 17; the second and third cycles of repeated dexamethasone were begun on day 30. Both groups of patients were treated for at least 3 months.

RESULTS

The response rate was 36% for patients treated with thalidomide alone and 72% for patients treated with thalidomide-dexamethasone, the latter including complete remission in 16% of patients. The median time to remission was 4.2 months with thalidomide alone and 0.7 months with thalidomide-dexamethasone. Grade 3 toxicity included infections (nine patients) and thrombotic/embolic events (seven patients). Five deaths have occurred as a result of multiple myeloma (two patients), infection (one patient), unknown cause (one patient), and a possible thromboembolic event (one patient).

CONCLUSION

Thalidomide alone was effective in patients with newly diagnosed myeloma. The combination with dexamethasone induced a high frequency of response, rapid onset of remission, and low incidence of serious irreversible toxicity. These observations support further studies of this promising combination for patients with newly diagnosed multiple myeloma.

Fludarabine/melphalan conditioning for allogeneic transplantation in patients with multiple myeloma

The purpose of the study was to determine the feasibility and efficacy of a reduced intensity conditioning regimen of fludarabine and melphalan for allogeneic transplantation in patients with multiple myeloma. From August 1996 to December 2000, 22 patients received a reduced intensity conditioning regimen with fludarabine and melphalan. Median age was 51 years (range, 45-64), median time from initial therapy to transplant was 36 months (range, 3-135 months). Disease phase prior to transplant was primary refractory in two patients, refractory relapse in 11 patients, sensitive relapse in eight patients and initial remission consolidation in one patient. The median number of prior therapies was five (range, 1-7), and median beta 2 microglobulin prior to transplant was 3.0 mg/l (range, 1.0-7.3). All patients received unmanipulated grafts from either HLA matched sibling donors (n = 13) or matched unrelated donors (n = 9). Eighteen patients received fludarabine 30 mg/m(2) for 4 days with melphalan 140 mg/m(2) as a single dose and four patients received fludarabine 25 mg/m(2) for 5 days with melphalan 90 mg/m(2) daily for 2 days. All 21 patients evaluable for engraftment achieved a neutrophil count of >0.5 x 10(9)/l after a median of 12 days (range, 9-24), 18 patients achieved platelet transfusion independence after a median of 14 days (range, 8-47). All engrafting patients had 100% donor cell engraftment. Seven patients achieved a complete remission. Six patients are currently alive with a median follow-up of 15 months (range, 10-47 months). The actuarial survival and progression-free survival is 30 +/- 11% and 19 +/- 9% at 2 years. Non-relapse mortality at 100 days was 19 +/- 10% and 40 +/- 10% at 1 year. Fludarabine/melphalan combinations are feasible and allow consistent engraftment of allogeneic progenitor cells from both related and unrelated donors in patients with multiple myeloma and should be explored in patients with less advanced disease.

Consolidation therapy of multiple myeloma with thalidomide-dexamethasone after intensive chemotherapy

BACKGROUND

After myeloablative therapy for multiple myeloma, progression-free survival is shorter for disease in partial remission rather than complete remission. In an attempt to induce more frequent complete remission, we assessed thalidomide-dexamethasone in patients with stable partial remission after intensive therapy.

PATIENTS AND METHODS

Twenty-one patients with multiple myeloma were identified with disease in stable partial remission after prior intensive therapy. Thalidomide-dexamethasone was given within 15 months after intensive therapy provided myeloma protein production had been reduced by >75% to a constant level for at least 4 months. Thalidomide was begun at a dose of 100 mg each evening, with increments of 50 mg every 7 days to a maximum of 300 mg. Dexamethasone was given concurrently in a dose of 20 mg/m(2) each morning for 4 days on days 1-4, 9-12 and 17-20, with resumption on day 35. The combination was continued for at least 3 months and patients with marked reduction of myeloma were maintained on thalidomide alone until disease progression.

RESULTS

Marked further reduction of myeloma by at least 90% occurred in 12 patients (57%), including four (19%) with disease converted to complete remission. Disease has progressed in six of 21 patients, whose median total remission was 22 months. Common side effects of constipation, fatigue, paresthesias and dry skin were mild, dose-related and reversible.

CONCLUSIONS

The combination of thalidomide-dexamethasone reduced tumor mass markedly in 57% of patients with stable, residual disease after myeloablative therapy. Such an effect may produce longer disease-free survival and/or preserve tumor sensitivity to later retreatment with previously effective drugs.

Persistence of myeloma protein for more than one year after radiotherapy is an adverse prognostic factor in solitary plasmacytoma of bone

BACKGROUND

Prognostic factors for solitary plasmacytoma of bone (SPB), whether measured before or after radiotherapy (RT), have not been established. The authors analyzed multiple factors for myeloma-free survival (MFS) and cause-specific survival (CSS) in SPB patients treated with RT alone.

METHODS

Between 1965 and 2000, 60 patients with carefully staged SPB were treated with RT alone at the M. D. Anderson Cancer Center. Patient ages ranged from 29-77 years (median, 54 years), and 75% of patients had a myeloma (M) protein in the blood and/or urine. No patients showed other lesions on skeletal survey or, in recent years, magnetic resonance imaging (MRI) of the spine; marrow aspirate was normal in all patients. Radiotherapy to the solitary lesion was given to a total dose of 30-70 Gy (median, 46 Gy). The authors analyzed the impact of multiple factors on MFS and CSS, including resolution v. persistence of M protein after RT, secretory v. nonsecretory disease at diagnosis, presence v. absence of an associated soft tissue mass on computed tomography or MRI scan, magnitude of serum M protein elevation at diagnosis, age, spinal v. nonspinal location, Karnofsky performance status, total RT dose, and tumor size.

RESULTS

Median follow-up was 7.8 years (range, 1.0-25.5 years). On multivariate analysis, persistence of M protein more than one year after RT was the only independent adverse prognostic factor for MFS (P = 0.005) and CSS (P = 0.04). Most patients with M protein that persisted for more than one year after RT were diagnosed with multiple myeloma within 2.2 years of treatment.

CONCLUSIONS

Patients with M protein that persists for more than one year after RT should be monitored frequently and considered for standard chemotherapy followed by intensive consolidation therapy when they either develop symptoms or show an increasing M protein level.