Objective evaluation of the role of vincristine in induction and maintenance therapy for myelomatosis. Medical Research Council Working Party on Leukaemia in Adults

Secondary primary malignancies in multiple myeloma: an old NEMESIS revisited

The treatment of myeloma has undergone extraordinary improvements in the past half century. These advances have been accompanied by a concern for secondary primary malignancies (SPMs). It has been known for decades that extended therapy with alkylating chemotherapy agents, such as melphalan, carries an increased risk of therapy-related myelodysplastic syndrome and/or acute myeloid leukemia (t-MDS/AML), with a cumulative risk as high as 10–15%. High-dose chemotherapy with autologous stem cell support became widely accepted for myeloma in the 1990s. Despite the use of high doses of melphalan, the risk of t-MDS/AML with this procedure is estimated to be less than 5%, with much of this risk attributable to pretransplant therapy. Recently, lenalidomide has come under scrutiny for its possible association with SPMs. It is too soon to declare a causal relationship at this time, but there appears to be an increased number of SPMs in reports from several studies using lenalidomide maintenance. Current studies should be amended and future studies planned to better define the risk of SPMs and the risk factors and mechanisms for its development. Patients should be educated regarding this potential concern but the current use of lenalidomide should not generally be altered until further data are available.

Adjusting for patient crossover in clinical trials using external data: a case study of lenalidomide for advanced multiple myeloma

OBJECTIVES

In some trials, particularly in oncology, patients whose disease progresses under the comparator treatment are crossed over into the experimental arm. This unplanned crossover can introduce bias in analyses because patients who crossover likely have a different prognosis than those who do not cross over; for instance, sicker patients not responding to standard therapy or those expected to benefit the most may be selectively chosen to receive the experimental treatment. Standard statistical methods cannot adequately correct for this bias. We describe an approach designed to minimize the impact of crossover, and illustrate this by using data from two randomized trials in multiple myeloma (MM).

METHODS

The MM-009/010 trials compared lenalidomide and high-dose dexamethasone (Len+Dex) with dexamethasone alone (Dex). Nearly half (47%) of the patients randomized to Dex crossed over to Len with or without Dex (Len+/-Dex) at disease progression or study unblinding. Data from these trials was used to predict survival in an economic model evaluating the cost-effectiveness of lenalidomide. To adjust for crossover, the prediction equations were calibrated to match survival with Dex or Dex-equivalent therapies in trials conducted by the Medical Research Council (MRC) in the United Kingdom. To adjust for differences between the MM and MRC trial populations, a prediction equation was developed from the MRC data and used to predict survival by setting predictors to mean values for patients in the MM-009/010 trials. The expected survival with Dex without crossover was then predicted from the calibrated MM-009/010 equation (i.e., adjusted to match survival predicted from the MRC equation).

RESULTS

The adjusted median overall survival predicted by the MRC equation was 19.5 months (95%CI, 16.6-22.9) for patients with one prior therapy, and 11.6 months (95% CI, 9.5-14.2) for patients with >1 prior therapy. These estimates are considerably shorter than was observed in the clinical trials: 33.6 months (27.1-NE) and 27.3 months (95% CI, 23.3-33.3) as of December 2005.

CONCLUSION

The calibration method described here is simple to implement, provided that suitable data are available; it can be implemented with other types of endpoints in any therapeutic area.

Maintenance treatment of multiple myeloma

In multiple myeloma (MM), low-cost maintenance treatment has some attractions, since maintenance of a small tumor is usually compatible with a fairly healthy state. However, the great majority of the studies of maintenance treatment have failed to show any clinical benefit. Based on simple theoretical consideration, it is shown that in MM response duration and survival are affected primarily by the residual tumor mass after primary treatment, and by the kinetics of the tumor. Continuation of maintenance treatment is likely to have a moderate effect. The main cause of that is identified in the presence or in the development of a substantial proportion of drug-resistant cells. Preliminary data suggest that only alpha-interferon can be useful for maintenance, and that it can act by slowing down the kinetics of the tumor.

Complications of myeloma therapy

The advent of new therapies for multiple myeloma brings new hope for patients but also new side effects. Emerging information about the risks of supportive care therapies, including long-term, high-intensity bisphosphonate use and erythropoiesis-stimulating agents, is examined. As the number of drugs in the myeloma armamentarium grows, so does the list of possible side effects and interactions. With current progress, not only are there more complications to consider but patients are also living longer and the risk for delayed complications is becoming more relevant. The author provides perspective about the risks for the most active and commonly used single-agent and combination myeloma therapies.

Treatment of newly diagnosed multiple myeloma based on Mayo Stratification of Myeloma and Risk-adapted Therapy (mSMART): consensus statement

Multiple myeloma is a neoplastic plasma cell dyscrasia that on a yearly basis affects nearly 17,000 individuals and kills more than 11,000. Although no cure exists, many effective treatments are available that prolong survival and improve the quality of life of patients with this disease. The purpose of this consensus is to offer a simplified, evidence-based algorithm of decision making for patients with newly diagnosed myeloma. In cases in which evidence is lacking, our team of 18 Mayo Clinic myeloma experts reached a consensus on what therapy could generally be recommended. The focal point of our strategy revolves around risk stratification. Although a multitude of risk factors have been identified throughout the years, including age, tumor burden, renal function, lactate dehydrogenase, beta2-microglobulin, and serum albumin, our group has now recognized and endorsed a genetic stratification and patient functional status for treatment.

High-dose chemotherapy with autologous hematopoietic stem cell transplantation in patients with multiple myeloma

Multiple myeloma, for all practical purposes, remains an incurable malignancy; however, 5-year survival has improved substantially during the past 30 years. A major contribution to improved outcome is the use of high-dose chemotherapy and stem cell transplantation. This multifaceted approach to therapy requires an understanding of appropriate induction therapy, techniques for stem cell mobilization, appropriate conditioning and supportive care. Also of importance are prognosis, features that predict outcome, the suitability of transplant candidates, and post-transplantation maintenance therapy.

Melphalan and Prednisone (MP) Regimen for Multiple Myeloma

The increasing complexity of cancer chemotherapy makes it mandatory that pharmacists be familiar with these highly toxic agents. This column focuses on the commercially available and investigational agents used to treat malignant diseases and reviews issues related to the preparation, dispensing, and administration of cancer chemotherapy.

Management of multiple myeloma: a systematic review and critical appraisal of published studies

We have done a systematic review of all randomised studies in myeloma, identified through a comprehensive search. Our aim was to investigate and critically examine the effects of various treatment modalities on outcome in patients with multiple myeloma and address 22 specific clinical questions in the management of this disease. As a result of our analysis we identified two therapeutic advances in the management of myeloma that, according to the evidence, are most important for improving outcome. These advances were: introduction of high dose chemotherapy, which appears to be superior to conventional chemotherapy, and the use of bisphosphonates, which decrease the probability of pathological vertebral fractures. However, the overall quality of the body of evidence for myeloma management was poor. Many trials were done with small sample sizes, and did not include reporting power analysis. The majority of studies had inadequate allocation concealment, and few were analysed according to intention to treat principle. We conclude that the quality of total evidence supporting treatment recommendations in myeloma is modest at best and has an ample scope for improvement.

Impact of early response to sequential high-dose chemotherapy on outcome of patients with advanced myeloma and poor prognostic features

We report the results of a dose-intense chemotherapy regimen designed to rapidly induce remissions in patients with advanced multiple myeloma (MM). Patients received VAD for 3-6 cycles depending on response kinetics. This was followed by three sequential cycles of cyclophosphamide (CTX) at 3 g/m2 every 15 days with G-CSF support. 71% of these patients had stage IIIa, 23% had renal failure. The median age was 58, median beta-2 microglobulin 4.6 and median albumin was 3.5, indicating poor prognosis. Of 35 patients, 66% achieved a complete response (CR) (SWOG). Six patients (18%) had a partial response. Fifty percent of the patients with renal failure recovered their kidney function. High-dose CTX contributed to tumor-mass reduction particularly in patients presenting with high-tumor burden. Tumor-mass reduction following three pulses of dexamethasone (4 days each) is significantly higher than with one pulse (p < 0.005). While high beta-2 microglobulin and LDH levels (p < 0.05) were associated with poor outcome, patients who responded faster to chemotherapy had a longer survival (p = 0.005). We conclude that this regimen is safe and effective. A rapid response may be useful in selecting patients who may benefit from further high dose chemotherapy and stem cell support.

Malignancy: Myeloma - the Elusive Cure

Myeloma accounts for 1% of all malignancies and is characterised by the malignant expansion of plasma cells. It is essentially incurable with a median survival of 6 months untreated. Typically disseminated at presentation, myeloma requires systemic therapy, in those patients with advanced or progressive disease. Of single agent therapies, oral mephalan remains the gold standard, either alone or in combination with steroids. 40% will respond with an increase in median survival from under 1 year to around 36 months. Combination chemotherapy produces an advantage in remission induction but no clear benefit for either survival or remission duration has been shown over standard melphalan and prednisolone. Significant melphalan dose escalation produces increased response rates and increased complete remission rates, however at the expense of increased toxicity. This has been ameliorated to an extent using stem cell support, however, although autografting may be superior to conventional chemotherapy it is not a curative treatment and modifications such as purging or tandem procedures remain to be fully evaluated. Allogeneic transplantation is only an option in a tiny minority of patients and has a high treatment-related mortality. Interferon alpha may improve the relapse free survival but has little effect on overall survival as the majority of patients will relapse. Experimental approaches, such as P-gp inhibition or thalidomide, are appropriate in this poor prognosis group. In many patients palliative care remains the only therapeutic option and close attention should be therefore paid to the prevention and treatment of renal failure, anaemia, infection, hypercalcaemia and bone disease.

Mechanisms of action of and resistance to antitubulin agents: microtubule dynamics, drug transport, and cell death

PURPOSE

To analyze the available data concerning mechanisms of action of and mechanisms of resistance to the antitubulin agents, vinca alkaloids and taxanes, and more recently described compounds.

DESIGN

We conducted a review of the literature on classic and recent antitubulin agents, focusing particularly on the relationships between antitubulin agents and their intracellular target, the soluble tubulin/microtubule complex.

RESULTS AND CONCLUSION

Although it is widely accepted that antitubulin agents block cell division by inhibition of the mitotic spindle, the mechanism of action of antitubulin agents on microtubules remains to be determined. The classic approach is that vinca alkaloids depolymerize microtubules, thereby increasing the soluble tubulin pool, whereas taxanes stabilize microtubules and increase the microtubular mass. More recent data suggest that both classes of agents have a similar mechanism of action, involving the inhibition of microtubule dynamics. These data suggest that vinca alkaloids and taxanes may act synergistically as antitumor agents and may be administered as combination chemotherapy in the clinic. However, enhanced myeloid and neurologic toxicity, as well as a strong dependence on the sequence of administration, presently exclude these combinations outside the context of clinical trials. Although the multidrug resistance phenotype mediated by Pgp appears to be an important mechanism of resistance to these agents, alterations of microtubule structure resulting in altered microtubule dynamics and/or altered binding of antitubulin agents may constitute a significant mechanism of drug resistance.

Expression of adhesion molecules in malignant plasma cells in multiple myeloma: comparison with normal plasma cells and functional significance

Malignant plasma cells in multiple myeloma are predominantly confined to the bone marrow, where they stimulate cytokine production by stromal cells and bone cells leading to osteoclast activation and formation of the characteristic lytic lesions in the skeleton. Adhesion molecules are critically involved in the cellular interactions between myeloma cells and stromal elements and may represent novel therapeutic targets to reduce osteolytic bone disease in multiple myeloma. Here, we review the literature on the adhesion molecule repertoire expressed by malignant plasma cells and discuss the evidence that adhesive interactions between myeloma cells and stromal cells stimulate production of bone-resorbing cytokines.

Diagnosis, prognosis, and standard treatment of multiple myeloma

The diagnosis of multiple myeloma (MM) is often difficult; most patients present with asymptomatic gammopathy. The only findings that confirm a diagnosis of MM are an elevation in the M-component or extension of the lytic bone lesions that are the hallmark of the disease. Tests that delineate plasma cell biology, such as plasma cell proliferation rate, are helpful; magnetic resonance imaging can disclose bone marrow lesions leading to subsequent osteolytic disease. After the diagnosis of MM has been established and prognostic factors identified, the appropriate therapy can be determined. Melphalan and prednisone are no longer considered to be the "gold standard" of therapy. In fact, this approach is suitable for less than half of patients with myeloma. This article presents guidelines for standard treatment options and examines the efficacy of new high-dose chemotherapy approaches.

[Prognosis of multiple myeloma treated with conventional chemotherapy has not improved in 20 years]

The treatment of multiple myeloma has changed over the last 20 years. We investigated the effects of theses changes on patient survival in the current practice of a rheumatology ward. Two hundred and seventy-nine patients were hospitalised between 1972 and 1993: 30 from 1972 to 1976, 70 from 1977 to 1981, 86 from 1982 to 1986, 75 from 1987 to 1991 and 18 from 1992 to 1993. Staging according to Durie and Salmon was I in 8%, II in 29% and III in 65%. In principle, the initial therapy was monochemotherapy in 65% of the cases and polychemotherapy in 35%. At the time of the present study, 197 patients have died. The actuarial curves of survival were similar in all historical classes defined by the date of first admission. Curves of median of follow-up and of floating means were level between 1972 and 1990. No correlation was found between the date of first admission and survival in the 174 patients who died between 1972 and 1987. The following parameters were associated with longer survival: achievement of an objective response on chemotherapy, lower patient's age, high haemoglobin, low creatinine, low stage according to Durie and Salmon, low number of plasma cells in bone marrow, low calcemia and low levels of IgA, monoclonal component. The comparison of prognosis factors in historical classes showed a difference only for haemoglobin which was lower in the earlier class. The type of the first chemotherapy regimen varied widely between historical classes. The number of responders was significantly greater after polychemotherapy than after monochemotherapy but no correlation was observed between the type of chemotherapy and survival. The frequencies of early death, and the causes of death in general, were not different in the historical classes. The lack of improvement of survival over the last 20 years shows that the efficacy of current chemotherapies is limited, a conclusion which warrants the exploration of other therapeutic avenues.

Experience with poorly myelosuppressive chemotherapy schedules for advanced myeloma. The Cooperative Group of Study and Treatment of Multiple Myeloma

In a multicentre study, 83 patients with advanced and previously uniformly treated multiple myeloma (MM) were randomised between cyclophosphamide (600 mg m-2) and epirubicin (70 mg m-2), administered every 3 weeks for three courses and both associated with prednisone and interferon-alpha2b. Both regimens were administered on an outpatient basis and had low haematological toxicity. Clinical results were similar. Overall response rate (43%) and median response and survival (5.9 and 14.1 months respectively) compare well with those obtained with more aggressive chemotherapy schedules.

Myeloma during a decade: clinical experience in a single centre

One hundred and fifty-six patients with multiple myeloma were treated over a period of 12 years at St. Bartholomew's Hospital. The progress of the disease was affected in 96/156 patients (61%). Response was defined as achieving a plateau of M component. A partial or complete response was seen in 68/120 patients treated conventionally (56.5%), and in 28/36 patients treated with high-dose therapy (77.7%). The median survival of the group as a whole was 20 months, with a 2-year survival of just over 40%. In the 36 patients treated with high-dose therapy, median survival was 6 years, and in a small group who have had maintenance Interferon therapy, the median has not yet been reached. In a univariate analysis, age, intensity of therapy, haemoglobin and creatinine levels were significant, but multivariate analysis showed that only age and intensity of therapy were independent predictors for survival. The outlook for relapsed patients who showed progression of disease remains poor, but palliation was best achieved by steroid and Interferon in combination. Patients who achieve complete responses and are maintained on Interferon appear to be doing better both in terms of freedom from symptoms and in survival, and methods to enable an elderly population to tolerate this form of therapy need to be explored.

Treatment of multiple myeloma according to the extension of the disease: a prospective, randomised study comparing a less with a more aggressive cystostatic policy. Cooperative Group of Study and Treatment of Multiple Myeloma

The purpose of the study was to ascertain whether the prognostic significance of staging in multiple myeloma (MM) is influenced by the aggressiveness of effective induction treatment and/or by continuing or discontinuing maintenance chemotherapy. Patients with untreated stage I MM (defined according to Durie and Salmon) were randomised between being followed without cytostatics until the disease progressed and receiving six courses of melphalan and prednisone (MP-P) just after diagnosis; stage II patients were uniformly treated with MPH-P and stage III patients were randomised between MPH-P and four courses of combination chemotherapy with Peptichemio, vincristine and prednisone (PTC-VCR-P). Within each stage, responsive patients were randomised between receiving additional therapy only until maximal tumour reduction was reached (plateau phase) and continuing induction therapy indefinitely until relapse. With resistant, progressive or relapsing disease, patients originally treated with MPH-P for induction received combination chemotherapy and vice versa. The overall first response rate was 43.8% (42.2% in 206 stage I, II and III patients treated with MPH-P and 48.0% in 75 stage III patients treated with combination chemotherapy, P = NS). Combination chemotherapy was more myelotoxic than MPH-P and, in particular, caused more non-haematological side-effects. Both the less and the more aggressive induction policies gave the same disease control. Progression of disease was statistically similar in stage I patients who were initially left untreated and in t hose who received MPH-P just after diagnosis; median duration of first response was similar in stage III patients receiving MPH-P and in those on combination chemotherapy. In all stages, discontinuing or continuing maintenance did not alter the median duration of first response. The overall second response rate was 28.5% (34.0% to MPH-P and 25.3% to combination chemotherapy, P = NS). Median survival was greater than 78 months in stage I, was 46.3 months in stage II and was 24.3 months in stage III patients, still independent of both induction and post-induction policies. In MM, the significance of staging for survival is independent of both the aggressiveness of induction and of continuing or discontinuing maintenance chemotherapy after the maximal tumor reduction has been achieved. Both MPH-P and and the association of PTC, VCR and P are effective in inducing first response and also second response in patients failing on the alternative regimen, but PTC-VCR-P causes more side effects. Thus, the overwhelming majority of patients with MM can safely be given MPH-P as first therapy, and this treatment may be delayed in early diseases.

Timed-sequential high-dose cyclophosphamide and vincristine in the treatment of multiple myeloma

BACKGROUND

This study was designed to examine the efficacy and toxicity of high-dose cyclophosphamide (CY), and to evaluate the potential added effect of vincristine (VCR) given at a theoretic time of malignant cell stimulation in a group of patients with multiple myeloma, refractory to or relapsing after, treatment with standard doses of chemotherapy.

METHODS

Patients were randomly assigned to receive CY 2400 mg per M2 as a single-day dose and VCR 1.4 mg per M2 given on Day 1 or Day 9 after the CY.

RESULTS

There were 108 cases suitable for analysis. No difference in objective response (17.6%, 23.5%), subjective response, remission duration, or survival was observed in the two treatment arms.

CONCLUSIONS

The authors conclude that a single, high dose of cyclophosphamide is more toxic and provides equal or less response than the equivalent dose given over 4 consecutive days and that no improved effect was detected using timed-sequential therapy with VCR.

Multiple myeloma presenting as an acute abdomen

We report a case of myeloma which presented as an acute abdomen with an associated pancreatic mass. This clinical picture has not been reported previously.

Combined chemotherapy with ABCM versus melphalan for treatment of myelomatosis. The Medical Research Council Working Party for Leukaemia in Adults

Both melphalan and cyclophosphamide increase life expectancy in patients with myelomatosis, but few large randomised studies have compared combination chemotherapy regimens with these single agents. In the Vth MRC myelomatosis trial, the survival of 314 patients randomised to receive ABCM (adriamycin, BCNU, cyclophosphamide, and melphalan) as first-line treatment was significantly longer than that of 316 patients given intermittent melphalan (M7) (p = 0.0003). The 75%, median, and 25% survivals were 7, 24, and 42 months, respectively, with M7 and 10, 32, and 56 months, respectively, with ABCM. Stable disease with few symptoms (plateau) was achieved by 61% of patients given ABCM and 49% of those given M7 (p = 0.004). Myelotoxicity was comparable between regimens. Cross-trial analysis suggests that M7 is comparable to melphalan and prednisone or melphalan, prednisone, and vincristine; that the efficacy of ABCM in the Vth trial and VIth MRC trials is comparable; and that ABCM gave better survival than intermittent melphalan regimens in the prognostic groups analysed. The results indicate that ABCM is an acceptable regimen that is more effective than melphalan, with or without prednisone, for first-line treatment of myelomatosis.

Phase I-II trial of high-dose melphalan in previously untreated stage III multiple myeloma: Cancer and Leukemia Group B study 8512

To study the efficiency of high-dose melphalan in previously untreated patients with advanced myeloma, we performed a Phase I-II trial. Twenty-eight patients were treated at dose level of 60-140 mg/m2. Each patient was first treated with a priming dose of cyclophosphamide (300 mg) followed by high-dose melphalen 1 week later. One course of therapy was given. Patients were then followed without further therapy until relapse. Clinical and laboratory features of the 28 patients in this study included: median age 63, performance status 0-2, hypercalcemia 21%, bone pain 82%, paraprotein types: IgG 76%, Iga 20%, and paraproteinuria 71%. Because none of the patients achieved complete remission (CR) at 60 mg/m2, despite life-threatening toxicity in all patients, the dose level was rapidly increased to 140 mg/m2, a dose previously reported to induce a high percentage of CR. At this dose, CR was achieved in only 1 of 11 patients (9%). This patient had multiple plasmacytomas without generalized bone marrow involvement. One additional patient at 100 mg/m2 achieved CR. Of the whole group, 12 achieved PR. Durations of remissions were generally short: CR 6.3 and 18+ months and PR 2.3-18 month, median 6.9 months. Life-threatening myelosuppression was universal with prolonged pancytopenia. Treatment-related deaths from sepsis were observed in 29% of patients. The median survival of the entire group was 15.6 months. Older patients in this trial did not tolerate high-dose melphalen therapy well; this resulted in a high proportion of toxic deaths and poor overall survival.

Second and third responses to the same induction regimen in relapsing patients with multiple myeloma

From September 1975 to December 1986, 115 consecutive previously untreated patients with multiple myeloma (MM) were treated with combination chemotherapy consisting of BCNU, cyclophosphamide, melphalan, vincristine, and prednisone (M-2). No patients were excluded or lost during follow-up. Forty-three percent of the patients were Stage I plus II, and 57% were Stage III. Thirty-eight patients (33%) had blood urea nitrogen greater than or equal to 40 mg/dl (substage B). Reaching an objective response treatment was stopped, generally after 1 year, and restarted at relapse. After induction therapy, 94 patients (82%) responded and had a median duration of response (MDR) of 22 months. After first relapse, 26 of 38 patients (69%) responded again to the same regimen and had an MDR of 11 months. This response rate and MDR are significantly lower than the ones achieved in induction chemotherapy. After second relapse, 7 of 16 patients (44%) again responded with an MDR of 3.5 months. The median survival time (MST) was 50.5 months for all patients. The most relevant side effect was leukopenia. No case of secondary leukemia was noticed. The authors conclude that patients with MM can be treated safely without maintenance therapy after reaching remission because a high response rate can be obtained in first and even second relapse. The planned treatment pause at remission does not adversely affect the survival time. Secondary leukemia is infrequent after this policy. Quality of life improves during the treatment pause.

Natural killer cell activity in monoclonal gammopathies: relation to disease activity

Natural killer (NK) activity and NK-related cell surface markers (CD16, CD56, CD57) of peripheral blood lymphocytes were studied in patients with multiple myeloma and MGUS (monoclonal gammopathy of undetermined significance). A strong correlation (p less than 0.0001) was found between the numbers of cells positive for the different NK cell surface markers. The proportion of CD16+ cells correlated highly to the lytic capability (lytic units/10(6) cells) of K562 cells (p less than 0.0001). High NK activity and high numbers of cells with NK-related cell surface markers were found in patients with a low tumor burden compared to controls, whereas low values were seen in patients with an advanced disease. The results indicate that NK cells might be involved in the disease process in monoclonal gammopathies, perhaps by exerting a regulatory function on the proliferating B-cell clone.

Initial treatment in multiple myeloma: no advantage of multidrug chemotherapy over melphalan-prednisone. The Myeloma Group of Western Sweden

From October 1983 until December 1986, 164 patients with multiple myeloma stage II-III were included in a prospective randomized multi-centre study comparing melphalan-prednisone (MP) with multidrug chemotherapy (MDC). The patients comprised 77% of all newly diagnosed myeloma stage II-III cases reported from 18 hospitals covering the entire Health Care Region of Western Sweden (1.5 million inhabitants). Patients randomized to MP (29 stage II and 55 stage III patients) were given oral melphalan and prednisone every 6 weeks. For patients randomized to MDC, stage II patients (n = 25) were given VMCP every 4 weeks and stage III patients (n = 53) VBAP and VMCP alternately every 4 weeks. For stage II patients, the response rate for MP compared to VMCP was 69 versus 56% and the median survival 46 versus 33 months. For stage III the response rate for MP compared to VBAP/VMCP was 58 versus 57% and the median survival 26 versus 24 months. No statistically significant differences were seen. The time to response and remission duration were also similar in both treatment arms. The dose intensity index (cumulative given/planned dose of myelosuppressive drugs) was greater than or equal to 0.8 in 89% of the MP patients and 81% of the MDC patients. Patients with index values less than 0.8 had the same response rate as patients with index greater than or equal to 0.8. This study has not demonstrated any advantage of MDC over traditional MP in multiple myeloma stage II-III.

Bulky extramedullary plasmacytomata: rare mode of relapse in myelomatosis

In two cases of myelomatosis relapse was accompanied by the development of bulky extramedullary plasma cell tumours, which created serious management problems. In both cases the histology was of a poorly differentiated plasmacytoid tumour with frequent mitoses. In one case paraprotein had completely disappeared from the serum and urine after six months' treatment with melphalan alone but did not correlate with improved survival. It is concluded that extramedullary spread of myelomatosis in the form of bulky tumour deposits is a rare and ominous mode of tumour progression or relapse. Rises in serum and urinary paraprotein concentrations are not the inevitable signs of relapse.

Selective induction of light chain synthesis in cultures of blood lymphocytes from patients with IgG myelomatosis

In the present study evidence is provided that neoplastic B cells from the blood from four of 24 patients with myelomatosis were activated selectively with polyclonal B cell mitogens. In three of these patients the activated cells produced light chains without heavy chains; of these, two patients had IgGK paraproteins and one had free lambda light chain disease. The ratio of kappa-expressing to lambda-expressing B cells in the initial blood B cell preparations was within the range for healthy controls for all four patients where neoplastic B cells were selectively activated. It is concluded that in some patients with myelomatosis the neoplastic clone is a mosaic of: (1) cells capable of synthesizing both light and heavy chains with (2) cells producing light chains only.

Multiple myeloma treated with high dose intravenous melphalan

High dose melphalan (HDM, 140 mg/m2 i.v.) has been evaluated in 58 patients under 63 years with multiple myeloma. Among previously untreated patients 11/41 (27%) entered a complete remission (CR: no measurable myeloma protein and a normal bone marrow) and 21 (51%) entered a partial remission (more than 50% reduction in myeloma protein and improvement in all other features). Median duration of remission is 19 months. Two patients who had responded to previous conventional treatment entered CR after HDM. Among 15 patients who had failed on previous chemotherapy the response rate was 66% including two CRs. However, in this group all patients have relapsed within 1 year. Profound myelosuppression, moderate nausea, vomiting, mucositis and diarrhoea with reversible alopecia occurred in all patients. There were 10 deaths within 2 months of treatment mainly due to sepsis and haemorrhage. In a subsequent study, high dose methyl prednisolone (1 g/m2 daily for 5 d) has been added to HDM. Response rates are similar with 6/22 (27%) CR, 13/22 (59%) PR and 2/22 NR but there was only one early death, reflecting improvements in medical management. The high CR rate is an encouraging feature of this approach which is now to be the basis of a prospective trial sponsored by the Medical Research Council in which HDM, with and without steroids, is compared to the best available conventional therapy (the MRC VI Myelomatosis trial).

Multiple myeloma in central Norway 1981-1982: a randomized clinical trial of 5-drug combination therapy versus standard therapy

67 previously untreated patients with multiple myeloma were entered on a randomized clinical trial to determine whether the use of combination chemotherapy including vincristine, carmustine, alkylating agents, and prednisone was more effective than conventional therapy with melphalan and prednisone. The treatment groups did not show significant differences with respect to major prognostic factors. With the 2-drug combination therapy and 5-drug combination therapy, 67 and 74% of the patients achieved remission, respectively. Moreover, no significant difference was found between the two treatment schedules in terms of median survival (30+ months). The survival curves for stage III patients treated with the two regimens did not differ significantly. After 12 months, patients who had achieved remission were randomized to have treatment discontinued or to have maintenance treatment. 7 of 15 patients on maintenance therapy relapsed, whereas 9 of 14 patients who had their therapy discontinued relapsed, and the survival of the two groups was similar.