Elevated risk of venous but not arterial thrombosis in Waldenström macroglobulinemia/lymphoplasmacytic lymphoma

BACKGROUND

Many malignancies, including multiple myeloma and its precursor, monoclonal gammopathy of unknown significant, are associated with an elevated risk of thromboembolism. There is limited information on the risk of thrombosis in patients with Waldenström macroglobulinemia (WM) and lymphoplasmacytic lymphoma (LPL).

OBJECTIVES

To assess the risk of venous and arterial thrombosis in WM/LPL patients in a large population-based cohort study in Sweden.

PATIENTS/METHODS

A total of 2190 patients with WM/LPL and 8086 matched controls were identified through Swedish registers between 1987 and 2005. Information on occurrence of venous and arterial thrombosis after the diagnosis of WM/LPL was obtained through the centralized Swedish Patient Register, with follow-up to 2006. Cox regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Patients with WM/LPL had a significantly increased risk of venous thrombosis and the highest risk was observed during the first year following diagnosis (HR = 4.0, 95% CI 2.5-6.4). The risk was significantly elevated 5 (HR = 2.3, 95% CI 1.7-3.0) and 10 years after diagnosis (HR = 2.0, 95% CI 1.6-2.5). There was no increased risk of arterial thrombosis during any period of follow-up time (10-year HR = 1.0, 95% CI 0.9-1.1).

CONCLUSIONS

Venous thrombosis is a significant cause of morbidity in patients with WM/LPL. The potential role of thromboprophylaxis in WM/LPL, especially during the first year after diagnosis and in patients treated with thrombogenic agents, needs to be assessed to further improve outcome in WM/LPL patients.

Bone morphogenetic protein-9 suppresses growth of myeloma cells by signaling through ALK2 but is inhibited by endoglin

Multiple myeloma is a malignancy of plasma cells predominantly located in the bone marrow. A number of bone morphogenetic proteins (BMPs) induce apoptosis in myeloma cells in vitro, and with this study we add BMP-9 to the list. BMP-9 has been found in human serum at concentrations that inhibit cancer cell growth in vitro. We here show that the level of BMP-9 in serum was elevated in myeloma patients (median 176 pg/ml, range 8–809) compared with healthy controls (median 110 pg/ml, range 8–359). BMP-9 was also present in the bone marrow and was able to induce apoptosis in 4 out of 11 primary myeloma cell samples by signaling through ALK2. BMP-9-induced apoptosis in myeloma cells was associated with c-MYC downregulation. The effects of BMP-9 were counteracted by membrane-bound (CD105) or soluble endoglin present in the bone marrow microenvironment, suggesting a mechanism for how myeloma cells can evade the tumor suppressing activity of BMP-9 in multiple myeloma.

New drugs and novel mechanisms of action in multiple myeloma in 2013: a report from the International Myeloma Working Group (IMWG)

Treatment in medical oncology is gradually shifting from the use of nonspecific chemotherapeutic agents toward an era of novel targeted therapy in which drugs and their combinations target specific aspects of the biology of tumor cells. Multiple myeloma (MM) has become one of the best examples in this regard, reflected in the identification of new pathogenic mechanisms, together with the development of novel drugs that are being explored from the preclinical setting to the early phases of clinical development. We review the biological rationale for the use of the most important new agents for treating MM and summarize their clinical activity in an increasingly busy field. First, we discuss data from already approved and active agents (including second- and third-generation proteasome inhibitors (PIs), immunomodulatory agents and alkylators). Next, we focus on agents with novel mechanisms of action, such as monoclonal antibodies (MoAbs), cell cycle-specific drugs, deacetylase inhibitors, agents acting on the unfolded protein response, signaling transduction pathway inhibitors and kinase inhibitors. Among this plethora of new agents or mechanisms, some are specially promising: anti-CD38 MoAb, such as daratumumab, are the first antibodies with clinical activity as single agents in MM. Moreover, the kinesin spindle protein inhibitor Arry-520 is effective in monotherapy as well as in combination with dexamethasone in heavily pretreated patients. Immunotherapy against MM is also being explored, and probably the most attractive example of this approach is the combination of the anti-CS1 MoAb elotuzumab with lenalidomide and dexamethasone, which has produced exciting results in the relapsed/refractory setting.

Pharmacokinetics of thalidomide in patients with impaired renal function and while on and off dialysis

There is a renewed interest in thalidomide for use in malignancies and systemic inflammatory diseases. Reduced renal function is not uncommon among patients with these disease states but the pharmacokinetics has not been fully investigated. The aim of this study was to investigate the pharmacokinetics of thalidomide in haemodialysis patients while on and off dialysis and in myeloma patients with varying degrees of renal function.

Two studies were performed. To establish the pharmacokinetics of thalidomide in patients with mild to moderate renal failure, blood samples were taken over 12 weeks from 40 patients with multiple myeloma. A second study was performed in six patients with end-stage renal disease both on a non-dialysis day and before and during a haemodialysis session. Thalidomide concentration was determined by HPLC. A one-compartment open model with first-order absorption and elimination was used to fit total thalidomide concentration to population pharmacokinetics and statistical models using the NONMEM program. Clearance and volumes were slightly below 10 L h−1 and 1 L kg−1, respectively, in both patient groups. The inter- and intra-patient variability was low. Clearance was doubled during dialysis. There was no correlation between thalidomide clearance and renal function. In conclusion, the pharmacokinetics of thalidomide in patients with renal failure are very similar to values reported by others for patients with normal renal function. Although clearance during dialysis is doubled, thalidomide dose need not be changed for patients with decreased kidney function. There is also no need for a supplementary dose due to haemodialysis.

gammaH2AX and cleaved PARP-1 as apoptotic markers in irradiated breast cancer BT474 cellular spheroids

Chemo- and radiotherapy induce apoptosis in tumours and surrounding tissues. In a search for robust and reliable apoptosis markers, we have evaluated immunostaining patterns of gammaH2AX and cleaved PARP-1 in paraffin-embedded cellular spheroids. Breast cancer BT474 cells were grown as cell spheroids to diameters of 700-800 microm. The spheroids contained an outer cell layer with proliferative cells, a deeper region with quiescent cells and a central area with necrosis. They were irradiated with 5 Gy and the frequency of apoptotic cells was determined at several time points (0-144 h) and distances (0-150 microm) from the spheroids surface. gammaH2AX and cleaved PARP-1 were quantified independently. Apoptotic frequencies for the two markers agreed both temporally and spatially in the proliferative regions of the spheroids. The gammaH2AX signal was stronger and had lower background compared to cleaved PARP-1. The central necrotic region was intensely stained with cleaved PARP-1, whereas no gammaH2AX could be detected. The apoptotic frequency increased with distance from surface for all time points. However, apoptotic frequencies, above unirradiated control levels, could only be detected for the last time point, 144 h after irradiation. We have shown that the spheroid model is a practical system for evaluation of staining patterns and specificities of apoptosis markers. Also, the radial gradient provides the opportunity to study apoptosis under a range of physiological conditions within the same system. We have further shown that gammaH2AX and cleaved PARP-1 are applicable markers for apoptosis in the proliferative regions of the spheroids. However, the more intense and clear staining patterns of gammaH2AX suggests that this marker is preferable for quantification of apoptosis in spheroids and similar paraffin-embedded materials.

International myeloma working group (IMWG) consensus statement and guidelines regarding the current status of stem cell collection and high-dose therapy for multiple myeloma and the role of plerixafor (AMD 3100)

Multiple myeloma is the most common indication for high-dose chemotherapy with autologous stem cell support (ASCT) in North America today. Stem cell procurement for ASCT has most commonly been performed with stem cell mobilization using colony-stimulating factors with or without prior chemotherapy. The target CD34+ cell dose to be collected as well as the number of apheresis performed varies throughout the country, but a minimum of 2 million CD34+ cells/kg has been traditionally used for the support of one cycle of high-dose therapy. With the advent of plerixafor (AMD3100) (a novel stem cell mobilization agent), it is pertinent to review the current status of stem cell mobilization for myeloma as well as the role of autologous stem cell transplantation in this disease. On June 1, 2008, a panel of experts was convened by the International Myeloma Foundation to address issues regarding stem cell mobilization and autologous transplantation in myeloma in the context of new therapies. The panel was asked to discuss a variety of issues regarding stem cell collection and transplantation in myeloma especially with the arrival of plerixafor. Herein, is a summary of their deliberations and conclusions.

Preleukemic syndrome simulating SLE. A case report

A 70-year-old man presented with symmetrical arthritis and arthralgias, Raynaud's phenomenon, pleurisy, fever, maculopapular erythema, leuko- and thrombocytopenia, anemia, antinuclear antibodies and hypocomplementemia. His bone marrow morphology was normal. During therapy with corticosteroids he developed pulmonary tuberculosis which responded well to tuberculostatic treatment. Approximately one year after onset of his initial symptoms, myeloblasts were seen in the blood and a few weeks later the bone marrow showed a myeloblastic leukemia. The patient did not respond to cytostatic treatment and died six weeks later. Although this patient presented symptoms suggesting the diagnosis of SLE, in retrospect his condition probably represented an unusual type of preleukemic syndrome.

Non-secretory or low-secretory myeloma with intracellular kappa chains. Report of six cases and review of the literature

This report concerns six cases of multiple myeloma characterized by either no demonstrable monoclonal immunoglobulin in plasma or urine or by trace amounts (less than or equal to 0.1 g/l) of monoclonal kappa chains in the urine. In all cases there was an infiltration of the bone marrow by plasma cells containing kappa chains but no heavy chains. A retrospective analysis was made of 126 consecutive cases of Bence Jones myeloma. The number of kappa and lambda cases was approximately the same. All cases secreting less than or equal to 0.1 g light chains per 1 urine were of kappa type. This contrasts with a kappa/lambda ratio of 1.4-1.9 among reported series of M-components containing both heavy and light chains. A review of reported cases of non-secretory myeloma revealed a preserved capacity for Ig synthesis in the majority of cases and among these a preponderance of kappa chain producing clones. These observations might be explained by a higher tendency for kappa chain producing cells to mutate to low secretors or to cells producing abnormal light chains which are catabolized rapidly. The clinical data from our patients do not indicate a more pessimistic prognosis in non- or low-secretory myeloma, than in other cases of multiple myeloma.

Immunofluorescent demonstration of the presence of protein HC on the surface of human lymphocytes

Indirect immunofluorescence was used to demonstrate the presence of protein HC on the surface of a large percentage of normal human peripheral blood lymphocytes. Protein HC is a recently described charge heterogeneous, complex-forming glycoprotein normally present in human plasma, urine and cerebrospinal fluid. The synthesis of protein HC by lymphocytes was indicated by the removal of the glycoprotein from the cell surfaces on trypsinization of the cells followed by the reappearance of the protein on continued cultivation of the cells.

Distribution of immunoglobulin-containing cells in bone marrow and lymphoid tissues in patients with monoclonal gammapathy

Cell suspensions of bone marrow and lymphoid tissue from 85 patients with monoclonal gammapathy were investigated by a direct immunofluorescence procedure for the detection of intracellular immunoglobulin alpha, mu, gamma, kappa and lambda chains. Serum Ig levels were determined and daily syntheric rates estimated. In all cases the majority of Ig-containing bone marrow cells contained the same Ig class as that of the M-component in serum or urine indicating a diffuse distriubtion of these clones in the bone marrow. This was observed not only in myeloma but also in benign monoclonal gammapathy (BMG) and lymphoma with an M-component. The M-component producing clone could be traced to extramedullary lymphoid tissue in myeloma but usually not in BMG. A positive correlation was found between the calculated synthetic rate of the M-component and the number of Ig-containing cells in the bone marrow and some indication was found that the synthetic rate per cell might be lower in IgM and IgG than in IgA monoclonal gammapathy. The depressed level of polyclonal Ig in myeloma and to some extent in BMG was parallelled by a diminished number of Ig-containing cells in the bone marrow.

Predominant B-lymphocyte deficiency in a case with lymph node disease resembling angioimmunoblastic lymphadenopathy

A case with clinical and histological features resembling angioimmunoblastic lymphadenopathy, but with a very marked decrease in B-lymphocytes instead of T-lymphocytes is presented.

Distribution of immunoglobulin-containing cells in human bone marrow and lymphoid tissues

Cell suspensions of human bone marrow, spleen, lymph nodes and palatine tonsils have been investigated for the presence of intracellular immunoglobulins by a direct immunofluorescence technique, using monospecific antisera against human Ig heavy chains alpha, mu and gamma and light chains kappa and lambda. Serum Ig levels were determined and the number of positive cells was compared with the concentration and calculated synthetic rate of serum Ig in each individual. The 28 patients studied covered a wide range of diagnoses and included those with normal as well as pathologically decreased or increased serum Ig levels. There was a high correlation between the calculated synthetic rate of each Ig class and the percentage of cells positive for the same Ig class in the bone marrow but not in the spleen, lymph nodes or tonsils. The Ig-containing cells constituted a much larger proportion of the total lymphoid cell population in the bone marrow than in the peripheral lymphoid organs. The estimated total number of Ig-containing cells was also much larger in the bone marrow than in the other organs investigated. It is concluded that in man the bone marrow is the major site of serum Ig synthesis and that the average synthetic rate per cell is the same regardless which of the three major Ig classes is produced. The role played by different lymphoid organs in humoral immunity is discussed in the light of the present results and reported data regarding lymphocyte and plasma cell kinetics in mammals.

An international field study of the reliability and validity of a disease-specific questionnaire module (the QLQ-MY20) in assessing the quality of life of patients with multiple myeloma

AIM

To test the reliability, validity and sensitivity of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-MY24 questionnaire, designed to assess the quality of life of myeloma patients with the QLQ-C30.

METHODS

The study was carried out through the EORTC Quality of Life Group using clinical trials in seven countries. All trials used the QLQ-C30 and QLQ-MY24 at baseline and a follow-up timepoint.

RESULTS

Two hundred and forty patients participated. The questionnaires were acceptable to patients. The hypothesised scale structure (disease symptoms, side-effects, body image and future perspective) was confirmed by multi-trait scaling, internal consistency and correlation analysis. Most scales demonstrated sensitivity to change and discriminated between clinically different patients. The social support scale (4 items) was removed due to observed ceiling effects.

CONCLUSION

The final questionnaire contains 20 items, QLQ-MY20, and is a reliable and valid instrument recommended for use with the QLQ-C30 in myeloma patients.

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.

Time factor for acute tissue reactions following fractionated irradiation: a balance between repopulation and enhanced radiosensitivity

Experimental data for acute radiation-induced skin reactions are reviewed. These show that for dose fractionation schedules with gaps, repopulation is initiated after a lag period. After this lag period, the isoeffective dose for a given level of skin reaction first increases rapidly, but then slows. The timing of the lag period is related to the total turnover time of the tissue under investigation and, for example, is shorter in rodent skin than in pig or human skin. At the point when accelerated repopulation is initiated, there is a major shortening of the turnover time of the target cell population. At this time, there is evidence, for a short period, for an increase in radiosensitivity of the surviving stem cells in a number of acutely responding normal tissues. This effect is clearly illustrated by the results of experiments using sequential dose fractionation schedules. Prolongation of the schedule from 'short' to schedules that include irradiation over the period when the cell turnover is accelerated is associated with a marked increase in tissue radiosensitivity. Clinically, this is best illustrated by a comparison of the effects of accelerated fractionation schedules, involving multiple fractions/day, with daily fractionation schedules. The increase in radiosensitivity produced by the prolongation of the treatment from 2 to 4-5 weeks was equivalent to > or =1 Gy day(-1). Comparable findings were obtained from animal studies. In the oral mucosa of mice, the initiation of accelerated cell proliferation in surviving cells is associated with the loss of dose sparing by subsequent dose fractionation due to the loss of the capacity to repair sublethal damage. Studies in pig and human skin have indicated that increased radiosensitivity is associated with a loss of cells in the G1 phase of the cell cycle. A collation of these two sets of findings suggests that the repair of sublethal damage takes place over this phase of the cell cycle. One clinical implication of these findings is that the alpha/beta ratio for acute skin reaction changes with the length of the overall treatment time; it is approximately 4.0 Gy for 'short' fractionation schedules that avoid any shortening of the cell cycle time. This increases to 11.2-13.3 Gy for schedules given in 3-4 weeks and to approximately 35 Gy for schedules given in 5-6 weeks. Results for pig skin were in total agreement with those for human skin.

No benefit from adding GM-CSF to induction chemotherapy in transforming myelodysplastic syndromes: better outcome in patients with less proliferative disease

In this prospective randomized multicenter trial 93 patients, median age 72 years, with RAEB-t (n=25) and myelodysplastic syndrome (MDS)-AML (n=68) were allocated to a standard induction chemotherapy regimen (TAD 2+7) with or without addition of granulocyte-macrophage-CSF (GM-CSF). The overall complete remission (CR) rate was 43% with no difference between the arms. Median survival times for all patients, CR patients, and non-CR patients were 280, 550, and 100 days, respectively, with no difference between the arms. Response rates were significantly better in patients with serum lactate dehydrogenase (S-LDH) levels </=9.5 microkat/l, bone marrow cellularity </=70%, and WBC counts <4.0 x 10(9)/l, but S-LDH was the only variable independently associated with response by logistic regression analysis. Cox's regression analysis identified four significant prognostic factors for survival: bone marrow cellularity, S-LDH, cytogenetic risk group (International Prognostic Scoring System), and age. Only bone marrow cellularity (P=0.01) and S-LDH (P=0.0003) retained statistical significance in the log-rank test. Severe adverse events were significantly more common in the GM-TAD arm (P=0.01). Thus, addition of GM-CSF to chemotherapy showed no clinical benefit in terms of response but carried an increased risk for side effects. We present a clinically useful tool to predict response to chemotherapy and survival in elderly patients with transforming MDS, favoring patients with features of less proliferative disease.

Cytogenetic features of multiple myeloma: impact of gender, age, disease phase, culture time, and cytokine stimulation

Relatively little is known about the cytogenetic features of multiple myeloma (MM) when compared to other hematologic malignancies. The reasons for this are most likely manifold, and include a low mitotic index of the malignant cells and the presence of cytogenetically cryptic abnormalities as well as of complex karyotypes with poor chromosome morphology. In the present study, we have investigated whether various culture conditions may influence the yield of abnormal metaphases in MM and, in the related plasma cell dyscrasias, monoclonal gammopathy of undetermined significance (MGUS) and plasmacytomas (PC). In addition, the possible impact of age, gender, and disease phase on the cytogenetic features has been analyzed. A total of 95 samples from 74 cases (68 MM, three PC, and three MGUS patients) were obtained for cytogenetic analysis. The samples were cultured either in conventional medium or in medium containing IL-6 and GM-CSF, and the culture times varied from 24 to 120 h. In total, 186 cultures were analyzed. Metaphase fluorescence in situ hybridization analysis using probes specific for 14q32, i.e. IGH rearrangements, could be performed in 57 of the 74 cases, and revealed 14q32 aberrations in 10 cases not seen by conventional G-banding. Abnormal karyotypes were detected in 77 (41%) of the 186 cultures, 46 (48%) of the 95 samples, and in 41 (55%) of the 74 patients, revealing a total of 20 chromosomal aberrations previously not reported in plasma cell dyscrasias. We found no evidence that gender, age, disease phase, culture time, or cytokine stimulation significantly influences the karyotypic features of MM.

Normal tissue response to low doses of radiotherapy assessed by molecular markers--a study of skin in patients treated for prostate cancer

The aim of this study was to evaluate normal tissue response by molecular markers to multifraction low doses of ionizing radiation, with the focus on changes in repopulation, estimated using Ki-67 as the proliferation marker, and on expressions of the p53 and p21 proteins, identified as key proteins in the DNA damage checkpoint. Repeated skin biopsies were taken from patients treated for prostate cancer with radiotherapy. The expressions of Ki-67, p53 and p21 of the keratinocytes in the basal cell layer of the epidermis were quantified immunohistochemically. The dose to the basal layer was 1.1 Gy per fraction, given five times per week for seven weeks. The indices of the three markers were determined over the whole period. A significant suppression of the Ki-67 index was observed during the first weeks, followed by a significant gradual increase in the Ki-67 index over the last weeks. The p53 and p21 protein levels were almost zero in the unirradiated skin. Upon irradiation, both the p53 and p21 index increased in a pattern very congruent to the Ki-67 index. In conclusion, daily fractions of about 1 Gy to the skin resulted in, for the keratinocytes in the basal layer, a cell growth arrest for a couple of weeks and a subsequent acceleration in repopulation during the following weeks of irradiation. The present findings also provided novel insights into the role of the p53/p21 pathway in the response of a normal epithelium to ionizing radiation as it is applied in radiotherapy.

Health-related quality of life in multiple myeloma patients receiving high-dose chemotherapy with autologous blood stem-cell support

In a population-based study, the Nordic Myeloma Study Group found a survival advantage for high-dose melphalan with autologous blood stem-cell support compared to conventional chemotherapy in myeloma patients under 60 yr of age (risk ratio: 1.62; confidence interval [CI] 1.22-2.15; p = 0.001). A study of health-related quality of life (HRQoL) was integrated in the trial, using the EORTC QLQ-C30 questionnaire. Of the 274 patients receiving intensive therapy 221 (81%) were compared to 113 (94%) of 120 patients receiving conventional melphalan-prednisone treatment. Prior to treatment, there were no statistically significant differences in any HRQoL score between the two groups. One month after the start of induction chemotherapy, the patients on intensive treatment had more sleep disturbance than the control patients. At 6 mo, corresponding to a mean of 52 d after high-dose melphalan, the patients on intensive treatment had moderately lower scores for global QoL and role and social functioning and there was also a significantly higher score for appetite loss. At 12 and 24 mo, the HRQoL was similar to that of the control patients. At 36 mo, there was a trend toward less fatigue, pain, nausea, and appetite loss in the intensive-treatment group. Thus, the 18 mo of prolonged survival seem to be associated with a good health-related quality of life. Despite the moderate HRQoL reduction associated with the early intensive chemotherapy phase, this treatment modality must be regarded as an important step forward in the care of multiple myeloma.

Low-dose hypersensitivity: current status and possible mechanisms

PURPOSE

To retain cell viability, mammalian cells can increase damage repair in response to excessive radiation-induced injury. The adaptive response to small radiation doses is an example of this induced resistance and has been studied for many years, particularly in human lymphocytes. This review focuses on another manifestation of actively increased resistance that is of potential interest for developing improved radiotherapy, specifically the phenomenon in which cells die from excessive sensitivity to small single doses of ionizing radiation but remain more resistant (per unit dose) to larger single doses. In this paper, we propose possible mechanisms to explain this phenomenon based on our data accumulated over the last decade and a review of the literature.

CONCLUSION

Typically, most cell lines exhibit hyper-radiosensitivity (HRS) to very low radiation doses (<10 cGy) that is not predicted by back-extrapolating the cell survival response from higher doses. As the dose is increased above about 30 cGy, there is increased radioresistance (IRR) until at doses beyond about 1 Gy, radioresistance is maximal, and the cell survival follows the usual downward-bending curve with increasing dose. The precise operational and activational mechanism of the process is still unclear, but we propose two hypotheses. The greater amount of injury produced by larger doses either (1) is above a putative damage-sensing threshold for triggering faster or more efficient DNA repair or (2) causes changes in DNA structure or organization that facilitates constitutive repair. In both scenarios, this enhanced repair ability is decreased again on a similar time scale to the rate of removal of DNA damage.

[High-dose melphalan with stem cell support is now an established myeloma therapy. Treatment of myeloma from a 30-year perspective]

Melphalan and prednisone have been the backbone in myeloma therapy for more than 40 years. New developments in chemotherapy and supportive therapy, achieved during the two decades which preceded the use of high-dose chemotherapy with stem cell rescue, have not changed the overall prognosis. A study of high-dose melphalan with autologous stem cell support on 274 patients < 60 years, performed by the Nordic Myeloma Study Group, has shown a prolongation of the median survival by 1.5 years. The results confirm that this therapy is a major step forward in myeloma therapy. Cost-utility and quality-of-life studies show that high-dose therapy has acceptable costs and leads to a favorable long-term quality-of-life.

A microradiographic investigation of cancellous bone healing after irradiation and hyperbaric oxygenation: a rabbit study

PURPOSE

To analyze the effect of irradiation on cancellous bone healing at different times after irradiation and to study if hyperbaric oxygen therapy (HBO) would affect the bone healing capacity, when delivered directly after irradiation.

METHODS AND MATERIALS

Rabbits were given a single dose of 15 Gy (60)Co radiation to one hind leg, the other hind leg serving as control. A standardized defect through the femoral metaphysis of the rabbits was created by a trephine drill biopsy at different times after irradiation. New bone formation in the defect was evaluated by a new biopsy through the previous defect after a healing time of 8 weeks. The mineral contents of the biopsies were analyzed by microradiography and microdensitometry.

RESULTS

There was a large variation in the bone-forming capacity expressed as bone mineral content between the animals. No statistically significant differences could be detected regarding the effect of irradiation, HBO, or delayed surgery. Qualitative histology revealed more pronounced inflammation, fibrosis, and bone resorption in the irradiated bone.

CONCLUSIONS

No definite conclusions can be drawn from the results of this study, however it might be hypothesized that cancellous bone recovers faster than cortical bone from radiation trauma.

Frequent good partial remissions from thalidomide including best response ever in patients with advanced refractory and relapsed myeloma

Twenty-three patients with advanced and heavily pretreated myeloma were treated with thalidomide. Starting dose was 200 mg/d, and 20 patients had dose escalations up to 400 (n = 5), 600 (n = 12) or 800 mg/d (n = 3), usually in divided doses. Nineteen patients were refractory to recent chemotherapy, and four had untreated relapse after prior intensive therapy. Ten out of 23 patients (43%) achieved partial response (PR; nine with refractory and one with relapsed disease), six patients had minor response or stabilization of the disease and four had disease progression. Another three patients died early from advanced myeloma at less than 3 weeks of thalidomide therapy. Of the 10 patients with PR, seven had a better response than after any prior therapy, despite vincristine-doxorubicin-dexamethasone (VAD)-based treatment in all but one and high-dose melphalan with autologous stem cell support in four. Time to achieve PR was rapid in patients receiving thalidomide in divided doses (median 31 d). Responses also included reduced bone marrow plasma cell infiltration and improved general status. Normalized polyclonal gammaglobulin levels were seen in four cases. Six out of 10 patients with PR remained in remission with a median time on treatment of 23 weeks (range 15-50 weeks). Sedation was common but usually tolerable, and some patients continued full- or part-time work. Four patients had skin problems, three patients had pneumonia, one hypothyrosis, one sinus bradycardia and one minor sensory neuropathy. Thalidomide may induce good partial remissions in advanced refractory myeloma with tolerable toxicity, and should be evaluated in other settings for myeloma patients. Divided thalidomide doses seem to reduce time to achieve remission and may improve response rate.