Extramedullary progression despite a good response in the bone marrow in patients treated with thalidomide for multiple myeloma

Advances in the treatment of extramedullary disease in multiple myeloma

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Extramedullary multiple myeloma results in an adverse prognosis.

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Novel agents such as bortezomib, lenalidomide, pomalidomide, isatuximab and selinexor showed efficacy and were recommended to treat EMD.

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For EMD at special sites, marizomib has advantages in the treatment of CNS-MM; Daratumumab combining with intrapleural bortezomib administration is active in treating myelomatous pleural effusion.

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Based on treatment experience of EMD in our department, we summarized treatment approach for EMD.

Extramedullary disease (EMD) is characterized by plasma cells outside of bone marrow in multiple myeloma (MM) patients, which results in an adverse prognosis. The cornerstone of treatment consists of combination therapy including proteasome inhibitors, immunomodulatory agents, steroids, followed by consolidative autologous hematopoietic stem cell transplantation in eligible patients. This review summarized the recent advances in the treatment of EMD. Bortezomib based therapy showed efficacy and was recommended to treat EMD. Marizomib had advantages in the treatment of central nervous system-multiple myeloma (CNS-MM) because of its good central nervous system penetrability. Immunomodulatory drugs such as lenalidomide and pomalidomide have been reported to be effective. Isatuximab and selinexor were also active. Based on the treatment experience of EMD in our department, we summarized treatment approach for EMD. However, the benefits of patients with EMD from the new era of novel drugs were limited. Novel drugs combination, monoclonal antibody, molecular targeted therapy, cellular immunotherapy and autologous stem cell transplantation (ASCT) are under investigation. Therapeutic studies and clinical trials specifically target EMD should be conducted. Hopefully, these treatment options for EMD will be demonstrated efficacy in the future.

Expert review on soft-tissue plasmacytomas in multiple myeloma: definition, disease assessment and treatment considerations

In this review, two types of soft-tissue involvement in multiple myeloma are defined: (i) extramedullary (EMD) with haematogenous spread involving only soft tissues and (ii) paraskeletal (PS) with tumour masses arising from skeletal lesions. The incidence of EMD and PS plasmacytomas at diagnosis ranges from 1·7% to 4·5% and 7% to 34·4% respectively. EMD disease is often associated with high-risk cytogenetics, resistance to therapy and worse prognosis than in PS involvement. In patients with PS involvement a proteasome inhibitor-based regimen may be the best option followed by autologous stem cell transplantation (ASCT) in transplant eligible patients. In patients with EMD disease who are not eligible for ASCT, a proteasome inhibitor-based regimen such as lenalidomide-bortezomib-dexamethasone (RVD) may be the best option, while for those eligible for high-dose therapy a myeloma/lymphoma-like regimen such as bortezomib, thalidomide and dexamethasone (VTD)-RVD/cisplatin, doxorubicin, cyclophosphamide and etoposide (PACE) followed by SCT should be considered. In both EMD and PS disease at relapse many strategies have been tried, but this remains a high-unmet need population.

Comparison of Whole-Body DWI and 18F-FDG PET/CT for Detecting Intramedullary and Extramedullary Lesions in Multiple Myeloma

OBJECTIVE. The purpose of this study was to compare the ability of whole-body (WB) DWI and ¹⁸F-FDG PET/CT in detecting intramedullary and extramedullary lesions in multiple myeloma. MATERIALS AND METHODS. The study included 49 patients with multiple myeloma who had undergone WB DWI and PET/CT. Intramedullary lesions for each region were scored by a scoring system using WB DWI and PET/CT separately. Extramedullary lesions seen separately on WB DWI and PET/CT per patient were recorded. Patients with diffuse lesions of the whole spine seen using both modalities were defined as group A, and those with such lesions seen on WB DWI only were defined as group B. The mean scores assigned to intramedullary lesions using the two modalities, the numbers of extramedullary lesions detected by WB DWI and PET/CT, and the mean percentages of plasma cells in the two patient groups were compared. RESULTS. Scores were higher for WB DWI than for PET/CT in all regions of the body (p < 0.05) except the skull, both in patients with a new diagnosis of multiple myeloma and in previously treated patients. Mean (± SD) percentages of plasma cells were significantly higher in group A than group B (50.458% ± 16.036% vs 18.682% ± 15.524%; p = 0.00). The mean number of extramedullary lesions detected by WB DWI was slightly higher than the mean number detected by PET/CT, although there was no statistical difference (4.48 ± 6.70 vs 4.39 ± 6.46 lesions; p = 0.86). CONCLUSION. For detecting intramedullary lesions, WB DWI is more sensitive than PET/CT in all regions except the skull, both in patients with a new diagnosis and previously treated patients and especially in patients with a low percentage of plasma cells. For detecting extramedullary lesions, WB DWI has sensitivity equivalent to that of PET/CT. The use of both modalities may offer complementary information.

Pomalidomide-dexamethasone for treatment of soft-tissue plasmacytomas in patients with relapsed / refractory multiple myeloma

OBJECTIVE

The presence of plasmacytomas (Ps) in patients with multiple myeloma (MM) is associated with a poor outcome, both in patients treated conventionally and in patients treated with novel agents. Two types of plasmacytomas have being recognized: paraskeletal plasmacytomas (PPs) and extramedullary plasmacytomas (EMPs), being the incidence of EMPs lower but with worse prognosis. Our aim has been to analyze the efficacy of the pomalidomide-dexamethasone combination in this patient profile.

METHOD

In the present study, the efficacy of pomalidomide and dexamethasone in 21 patients from nine hospitals of Catalonia (Spain), with relapsed or refractory MM and Ps, was analyzed. For this purpose, we describe the evolution of paraprotein in serum and urine and the size of plasmacytomas during treatment with pomalidomide-dexamethasone.

RESULTS

While 34% of the patients achieved a paraprotein response, only two patients with PPs (9%) responded (RC and PR). There were no responses among patients with EMPs. The median progression-free survival from the start of treatment with pomalidomide/dexamethasone was only 1.7 months and the median overall survival of 4.5 months.

CONCLUSION

In conclusion, pomalidomide and dexamethasone has limited efficacy in patients with advanced MM and soft-tissue plasmacytomas.

How We Manage Patients with Plasmacytomas

PURPOSE OF REVIEW

To discuss the diagnostic approach, treatment options, and future considerations in the management of plasmacytomas, either solitary or in the context of overt multiple myeloma (MM).

RECENT FINDINGS

Advanced imaging techniques such as whole-body magnetic resonance imaging and positron emission tomography/computerized tomography are essential for the diagnostic workup of solitary plasmacytomas (SP) to rule out the presence of other disease foci. The role of flow cytometry and clonal plasma cell detection is currently under study together with other prognostic factors for the identification of patients with SP at high risk of progression to overt MM. Solitary plasmacytomas are treated effectively with local radiotherapy whereas systemic therapy is required at relapse. Clonal plasma cells that accumulate at extramedullary sites have distinct biological characteristics. Patients with MM and soft tissue involvement have poor outcomes and should be treated as ultra-high risk. A revised definition of SP that distinguishes between true solitary clonal PC accumulations and SP with minimal bone marrow involvement should be considered to guide an appropriate therapeutic and follow-up approach. Future studies should be conducted to determine optimum treatment approaches for patients with MM and paraskeletal or extramedullary disease.

Clinical features of multiple myeloma patients with isolated extramedullary relapse

This study sought to analyze the clinical features and prognosis of multiple myeloma with isolated extramedullary relapse and with the absence of systemic progression. The clinical features and outcome were retrospectively analyzed in six multiple myeloma patients. These patients had secretory multiple myeloma at diagnosis. When relapsed, the dissociation between medullary and extramedullary response was detected. The serum or urine monoclonal component was extremely low or absent. The plasma cells in bone marrow were <5%. All patients received new targeted therapies (thalidomide or bortezomib) before extramedullary relapse. It is difficult to achieve second remission for them. Even in those showing response, the duration of response was extremely short. The median of overall survival from diagnosis and from extramedullary relapse was 19 months and 6 months, respectively. The overall survival was significantly shorter compared to the patients without extramedullary involvement (84 months, P=0.001). These patients exhibited a special and rare relapse pattern. Patients with this relapse pattern were resistant to current therapies, including novel targeted agents and associated with poor prognosis.

Extramedullary Involvement of Lymph Nodes in Multiple Myeloma

Myeloma multiplex is a malignant disease of bone marrow plasma cells. It is usually confined to the bone marrow, but in rare cases, patients can develop extramedullary disease. The involvement of lymph nodes is rare and can be a diagnostic challenge. Here, we describe a 36-year-old male patient who presented with abdominal pain and discomfort initially. An abdominal ultrasound followed by computed tomography (CT) revealed retroperitoneal and mesenteric lymph node enlargement. Biopsies of the abdominal lymph node and infiltrated colon showed a plasma cell infiltrate positive for CD79α, CD38, CD138, kappa light chain and VEGF2. Multiple myeloma with extramedullary localization was diagnosed. After six cycles of chemotherapy consisting of doxorubicin, dexamethasone and thalidomide followed by autologous haematopoietic cell transplantation, the patient achieved complete remission. Specifically, a CT scan after therapy showed enlarged lymph nodes in the abdomen, but PET CT scans did not detect any metabolically active foci. Thee years after the completion of therapy, the patient remains in remission. This case illustrates a rare presentation of extramedullary myeloma involving the abdominal lymph nodes, which could have been potentially mistaken for a lymphoid malignancy.

Extramedullary progression of multiple myeloma despite concomitant medullary response to multiple combination therapies and autologous transplant: a case report

INTRODUCTION

Extramedullary myeloma that occurs during the clinical course of multiple myeloma is rare but is an independent poor prognostic factor with mortality of 73% and median survival of 12 months despite aggressive therapies including novel agents. The clinicopathological aspects, biology and management of extramedullary myelomas are poorly understood. Our case highlights the pathobiological aspects of this important but rare entity, and the repercussions of modern therapies.

CASE PRESENTATION

A 60-year-old Caucasian man initially presented with an anterior rib fracture. Subsequent workup revealed stage IIIB immunoglobulin G lambda multiple myeloma. A bone marrow biopsy showed sheets of plasma cells, harboring unfavorable cytogenetics including deletion of 17p and t(4;14). He achieved near complete remission and resolution of karyotypic abnormalities with three cycles of induction doxorubicin, thalidomide, and dexamethasone (clinical trial). This was followed by high-dose melphalan and autologous stem cell transplant. He relapsed 1 year later. His bone marrow at that time showed only a few scattered polyclonal plasma cells. He received three cycles of bortezomib and tanespimycin (clinical trial) and achieved very good partial response. He again relapsed 1 year later with multiple large peripheral soft tissue masses and lymph nodes. Biopsies of the peripheral lesions were consistent with extramedullary myeloma, but repeat bone marrow biopsy continued to show no evidence of intramedullary disease.

CONCLUSIONS

This is one of the few cases reported that illustrates the differential response of extramedullary compared to intramedullary myeloma to multiple standard combination therapies including novel therapeutics and transplant, resulting in a very short survival. Several mechanisms for intra-to-extra medullary migration and hence the differential treatment response have been hypothesized. Physicians should be aware of this problem during treatment with immunomodulatory drugs and proteasome inhibitors not only in relapsed but also in front-line setting. In such cases, there is a potential role for evolving targeted therapeutics as we continue to better understand the tumor biology.

Myeloma in scar tissue--an underreported phenomenon or an emerging entity in the novel agents' era? A single center series

Tumor relapse in scar tissue is uncommon in cancer patients. Likewise, extramedullary plasmacytoma (EMP) relapse in scar tissue in the setting of multiple myeloma (MM) has been rarely reported. We report a series of 3 patients whose disease progressed as EMP at the site of a wound from previous invasive procedures. All 3 patients were treated for the relapsed disease with different treatment modalities, but failed to respond adequately and died several months after relapse. At original MM diagnosis, all had advanced-stage disease. They were treated with novel agents with or without autologous hematopoietic stem cell transplantation and achieved either a complete or very good partial response. We suggest that these treatments, which have become the standard of care in MM, may permit a predominance of myeloma subclones which are independent of the bone marrow microenvironment. These myeloma subclones then gain a survival advantage in the active scar-tissue niche, allowing for their uncontrolled proliferation. This case series might represent an underreported phenomenon and therefore may indicate an emerging and difficult-to-treat disease in the era of targeted therapies in MM. Physicians treating MM should be aware of this phenomenon, especially when referring their patients for invasive procedures.

Role of dynamic contrast-enhanced sonography for characterization and monitoring of extramedullary myeloma: comparison with serologic data

OBJECTIVE

To measure blood perfusion in extramedullary myeloma by contrast-enhanced sonography, correlate it with specific hematologic parameters, and determine their utility for local and systemic response monitoring.

METHODS

Twenty-five consecutive patients (14 male and 11 female; median age, 68 years) with extramedullary myeloma were included. After intravenous administration of 2.4 mL of sulfur hexafluoride, extramedullary myeloma masses were examined for 60 seconds. All patients underwent contrast-enhanced sonography at baseline, and 15 were monitored additionally (3 weeks during therapy). Average peak perfusion, regional blood flow (RBF), and regional blood volume (RBV) were calculated. Baseline perfusion parameters were compared with short-term follow-up sonographic data and serologic biomarkers (M gradient). For validation of extramedullary myeloma and systemic myeloma, patients underwent midterm (<3 months) imaging and serologic diagnosis.

RESULTS

Patients with baseline β2-microglobulin (B2M) greater than 3.5 mg/L (n = 17) showed higher perfusion parameters compared with baseline B2M less than 3.5 mg/L (n = 8). At short-term follow-up, patients were classified by serologic criteria as responders (n = 9) and nonresponders (n = 6) and by sonographic criteria as responders (n = 10) and nonresponders (n = 5). In sonographic responders, mean peak, RBV, and RBF dropped from 59.13, 1446.09, and 71.52 (artificial units) at baseline to 29.30, 364.19, and 34.64 at follow-up (P < .05), whereas in nonresponders, perfusion parameters increased from 33.18, 789.82, and 36.92 at baseline to 51.14, 1491.06, and 65.34 at follow-up (P > .05). Prediction of a midterm course of systemic myeloma using serologic data yielded sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 0.66, 0.77, 0.66, and 0.77, whereas sonographic results (judged by RBV) yielded values of 0.66, 0.55, 0.5, and 0.71. Separate prediction of a local (extramedullary myeloma) response by sonography yielded sensitivity, specificity, PPV, and NPV of 0.8, 1.0, 1.0, and 0.71.

CONCLUSIONS

Contrast-enhanced sonography is a valuable tool for short-term monitoring of the treatment response in extramedullary myeloma.

Incidence, clinical features, laboratory findings and outcome of patients with multiple myeloma presenting with extramedullary relapse

Extramedullary plasmacytomas constitute a rare and not well studied subset of multiple myeloma (MM) relapses. We report the incidence, clinical-laboratory features and outcome of patients with MM and extramedullary relapse (ExMeR). A total of 303 patients with symptomatic MM were recorded in a 13-year period in two institutions. Twenty-eight cases of ExMeR (9%) were recorded. There was an increased frequency of elevated lactate dehydrogenase (LDH) (p = 0.026), bone plasmacytomas (p = 0.001) and fractures (p = 0.002) at diagnosis, in patients with ExMeR compared to the others. ExMeR was associated with an ominous outcome, high LDH, constitutional symptoms and a statistically significant decrease of monoclonal paraprotein compared to levels at diagnosis (p = 0.009). Prior treatment with bortezomib was associated with a decreased hazard of ExMeR (p = 0.041). Overall survival (OS) was decreased in patients with ExMeR compared to the others (38 vs. 59 months, p = 0.006). Patients with MM with ExMeR have a lower OS and their clinical and laboratory features differ from those without.

Abdominal manifestations of extraosseous myeloma: cross-sectional imaging spectrum

Extraosseous myeloma, defined as the myelomatous involvement outside the skeleton system, is rare and often associated with advanced multiple myeloma. There has been a recent increase in the clinicoradiological incidence of this entity, possibly secondary to increased survival of patients and frequent use of imaging. This has led to the development of new clinical staging guidelines for multiple myeloma, which include the use of imaging modalities positron emission tomography/computed tomography and magnetic resonance imaging for accurate detection and optimal management. The aims of this review were to discuss the significance of identification of extraosseous disease, to describe the spectrum and common sites of extraosseous involvement in the abdomen, and to review the imaging findings of extraosseous myeloma in the abdomen.

Response to low-dose bortezomib in plasma cell leukemia patients with malignant pleural effusion and ascites: a case report and a review of the literature

Pleural effusion or ascites complicating plasmacytoma is rare and has a poor prognosis. A 70-year-old man was diagnosed as plasma cell leukemia and one course of ranimustine-vindesine, melphalan, and prednisolone followed by melphalan and prednisone (MP) maintained a very good partial response. After MP he was diagnosed to have pleural effusion and ascites as a complication of the plasmacytoma. Low-dose bortezomib caused disappearance of the malignant effusion. The malignant effusions recurred after the end of the second course of bortezomib. High-dose dexamethasone vincristine, doxorubicin, cyclophosphamide, and prednisone yielded no benefit, the patient died of Aspergillus pneumonia.

Soft-Tissue Plasmacytomas in Multiple Myeloma: Incidence, Mechanisms of Extramedullary Spread, and Treatment Approach

We provide an overview on soft-tissue extramedullary plasmacytomas (EMPs) in multiple myeloma (MM). We reviewed the incidence of EMPs in MM, myeloma bone marrow homing, possible mechanisms of extramedullary spread, and prognosis and response to therapy. The incidence of EMPs is 7% to 18% at MM diagnosis and up to 20% at relapse. The current notion that EMPs are more frequent after treatment with novel agents remains to be proven, especially considering that different patterns of disease recurrence can emerge as patients live longer in the era of novel drugs. Bone marrow genetic abnormalities are not associated with extramedullary spread per se, which also suggests that microenvironmental interactions are key. Possible mechanisms of extramedullary spread include decreased adhesion molecule expression and downregulation of chemokine receptors. EMPs usually show plasmablastic morphology with negative CD56 expression. High-dose therapy with autologous stem-cell transplantation (ASCT) can overcome the negative prognostic impact of extramedullary disease in younger selected patients. EMPs do not typically respond to thalidomide alone, but in contrast, responses to bortezomib have been reported. The incidence of EMPs in patients with MM is high and is associated with poor outcome in patients treated conventionally. A potential first-line treatment option seems to be a bortezomib-containing regimen followed by ASCT, whenever possible. Experimental studies on the mechanisms of myeloma cell adhesion, myeloma growth at extramedullary sites, and drug sensitivity are priorities for this area of continuing therapeutic challenge.

Incidence, presenting features and outcome of extramedullary disease in multiple myeloma: a longitudinal study on 1003 consecutive patients

BACKGROUND

There are few data on the incidence and prognosis of extramedullary (EM) multiple myeloma (MM). There are concerns about a possible increase of EM relapses with the expanding use of high-dose therapy (HDT) and biological agents.

PATIENTS AND METHODS

The incidence of EM disease, its relationship with prior exposure to HDT or novel agents, and its prognostic impact were analyzed in 1003 MM patients. Based on the different therapies available, three periods were considered: 1971-1993, conventional-dose chemotherapy; 1994-1999, HDT for younger patients; and 2000-2007, introduction of novel agents.

RESULTS

Overall, 13% of patients had EM disease, 7% at diagnosis and 6% later. In the 2000-2007 period, there was a significant increase of EM involvement, at diagnosis (P = 0.02) and during follow-up (P = 0.03). The risk of EM spread was not significantly increased after HDT [hazard ratio (HR 0.6)], bortezomib (HR 1.62), or thalidomide/lenalidomide (HR 1.07). EM disease was associated with shorter overall (HR 3.26, P < 0.0001) and progression-free (HR 1.46, P = 0.04) survival.

CONCLUSIONS

The incidence of EM disease has increased, probably due to the availability of more sensitive imaging techniques and the prolongation of patients' survival. HDT or novel agents seem not to increase the risk of EM disease. EM involvement confers a poor prognosis.

Clinicopathological features of extramedullary recurrence/relapse of multiple myeloma

Extramedullary relapses of multiple myeloma (MM) during the course of disease are rare. We report a series of six patients with primary intramedullary MM that were treated with immunomodulatory therapy and/or stem cell transplant, and that later developed extramedullary relapses at various body sites. These six cases represent 3.9% of the 156 patients treated for MM at our institution over a 9-yr period (1999-2007). Five (83.3%) of the six cases showed immature/high-grade histology in the extramedullary relapses as compared with their antecedent MM. The neural cell adhesion molecule, CD56, was immunohistochemically demonstrable in 75% (three of four) of the original myelomas tested, but was absent in 83.3% (five of six) of their extramedullary relapses. The disease typically behaved aggressively and was rapidly fatal in all six patients even when therapy was administered. The median time of progression to extramedullary relapse was 29 months (range 9-64 months), and the median survival after diagnosis of the relapses was only 38 d (range 1-106 d). Our case series shows that extramedullary relapse of MM is characterized by high-grade histology, loss of CD56 expression, frequent resistance to current therapeutic regimens, aggressive biological behavior, and very short survival.

Extramedullary disease and targeted therapies for hematological malignancies—is the association real?

During the past years targeted therapies have gained a major role in the treatment of cancer patients, including those with hematological malignancies. Extramedullary involvement is a rare manifestation of acute and chronic leukemias and of multiple myeloma. Nevertheless, with the expanding use of targeted treatments there is an impression that the incidence of extramedullary relapses is increasing. We reviewed the reports on this phenomenon in patients treated with all-trans-retinoic acid and arsenic trioxide for acute promyelocytic leukemia, thalidomide and bortezomib for multiple myeloma and imatinib for chronic myeloid leukemia. The pathogenetic mechanisms suggested are: life prolongation by these treatments allowing for disease progression arising from dormant cells; poor penetration of the drugs to sanctuary sites like the central nervous system; the requirement of some of these drugs, especially thalidomide, for the marrow microenvironment to exert their action; and finally, a possible active role for some of the drugs, like all-trans-retinoic acid. Since the use of these targeted therapies is expanding we should be aware of this association.

Long-term results of thalidomide in refractory and relapsed multiple myeloma with emphasis on response duration

OBJECTIVE

Thalidomide administered as a single agent produces a response rate of about 40% in patients with refractory or relapsed multiple myeloma (MM). The aim of our study was to determine the quality and duration of such responses.

PATIENTS AND METHODS

Forty-two consecutive patients with refractory (20) or relapsed (22) MM were given thalidomide as a single agent at our institution. Most of them (70%) had previously received two or more lines of therapy, and 38% had undergone autologous stem cell transplantation.

RESULTS

Eighteen patients (43%) responded to thalidomide [11 minimal responses (MR) and seven partial responses (PR)] according to the European Marrow Transplant Registry (EBMT) criteria. The median time to response was 3 months and the median duration of therapy in responding patients was 9 months. Treatment was discontinued because of toxicity in 10 responding patients. The toxicity mainly led to peripheral neuropathy and fatigue. At the time of this analysis, all responding patients had progressed except one who remains in continued stable PR. The median time to progression was 15.6 months (range 1.3 to 70+), with a trend towards a longer duration for patients who achieved PR vs. MR (21.2 vs. 11.2 months, P = 0.11). The median duration of response was 12.4 months (range: 0.3-67+) (17.2 months for PR vs. 9.7 months for MR, P = 0.11).

CONCLUSION

These results show that the effect of thalidomide in refractory/relapsed MM can be sustained, particularly in patients who achieve a greater degree of response, and support the finding that this drug can be used for maintenance therapy.

Bortezomib: an effective agent in extramedullary disease in multiple myeloma

Bortezomib is a potent and selective proteasome inhibitor recently introduced in the treatment of multiple myeloma (MM). This drug produces significant responses in about one-third of patients with relapsed/refractory disease. We first recognized the lack of efficacy of thalidomide in soft-tissue plasmacytomas. There is little information on the effect of bortezomib on extramedullary myeloma. Four of 23 patients treated with bortezomib at our institution had extramedullary involvement at the time of relapse. In three of these patients large soft-tissue plasmacytomas disappeared. This indicates that bortezomib may be useful in clinical situations of extramedullary disease in which other agents, such as thalidomide, may not be effective.

Afectación cutánea específica en pacientes con mieloma múltiple. Estudio clínico-patológico, inmunohistoquímico y citogenético de 40 casos

INTRODUCTION

Specific cutaneous involvement in patients with multiple myeloma is very rare. When it does occur, it is in patients with advanced stages of multiple myeloma and with a large tumorous mass. In this study, we analyzed 40 patients with specific cutaneous involvement from multiple myeloma, with no bony lesions underlying the skin lesions, and we reviewed the related literature.

OBJECTIVES

We were particularly interested in the clinical course of these patients, including survival once skin metastases had developed and the possible influence of the different treatments administered.

MATERIAL AND METHODS

The study was completed by determining the histopathological pattern, the immunohistochemical profile, the type of immunoglobulin and immunoglobulin light chain produced by the neoplastic plasma cells that infiltrated the skin, as well as the cytogenetic characteristics of these cells.

RESULTS

From a clinical standpoint, the skin lesions consisted of multiple nodules or plaques with erythematous or violaceous coloration, and variable location. Histopathologically, two patterns were seen: nodular and diffuse interstitial. The plasma cells showed cytological atypia, and in one case they displayed a spindle shape, giving the lesion a sarcomatoid appearance. Immunohistochemically, these neoplastic plasma cells were strongly positive for CD79a, CD138, and EMA, while the immunoexpression of CD38 and CD43 was less intense and constant. In 39 of the 40 patients, the type of monoclonal immunoglobulin produced by the neoplastic plasma cells in the skin lesions was determined: 18 patients had IgA myeloma (5 IgAkappa and 13 IgAlambda), 19 patients had IgG myeloma (15 IgGkappa and 4 IgGlambda) and 2 patients had IgDlambda myeloma. The 22 cases in which immunoglobulin heavy chain gene rearrangement studies by PCR were carried out for the JH gene showed monoclonal rearrangement, while viral studies to try to identify genetic material of the HHV-8 virus and the Epstein-Barr virus gave negative results in all cases. These 22 cases studied using FISH showed the deletion of the rb-1 retinoblastoma gene in the neoplastic plasma cells that infiltrated the dermis. Despite aggressive chemotherapy, all of the patients died a few months after the skin lesions developed.

CONCLUSIONS

In our series, a perfect correlation was seen between the findings of serum electrophoresis and the immunohistochemistry of the skin lesions with regard to the type of immunoglobulin and the immunoglobulin light chain restriction produced by the neoplastic plasma cells. Patients with multiple myeloma have a very short survival period once specific skin lesions appear, regardless of the therapy administered. The deletion of the rb 1 gene may be a prognosis marker to identify those patients with especially aggressive forms of multiple myeloma.

Unusual cutaneous involvement during plasma cell leukaemia phase in a multiple myeloma patient after treatment with thalidomide: a case report and review of the literature

We report the case of a 54-year-old African-American male with IgG multiple myeloma (MM) with disease resistant to multiple chemotherapy regimens and immunomodulatory treatment with thalidomide. In spite of achieving a partial remission of short duration, his disease accelerated to peripheral plasmacytosis and subsequent development of cutaneous plasmacytomas. The malignant plasma cells derived from the dermal lesions were CD45+, CD38+, CD138+ and matched the immunophenotype of the plasmacytes during the leukaemic phase. Occurrence of extramedullary lesions in the setting of MM treated with thalidomide is of concern, although currently there are very few reports describing this association. We discuss the possible relationship between the patient's unusual disease course and the administered chemo- and immunotherapy. The significance of the changes in adhesion molecules, especially CD138 and CD56, relevant to the development of cutaneous plasmacytomas is discussed.

Hepatic Plasmacytosis as a Manifestation of Relapse in Multiple Myeloma Treated With Thalidomide

Thalidomide and its analogs have been extensively studied in patients with multiple myeloma. We present the case of a 58-year-old female patient with immunoglobulin GA-kappa multiple myeloma who was receiving thalidomide after failing an autologous transplant. She presented with profound asthenia and several space-occupying hepatic lesions, one of which was shown by a CT-guided percutaneous biopsy to be plasmacytoma. The patient then received bortezomib and had a transient response. Because thalidomide may also increase the expression of cytoadhesion molecules in myeloma cells and in the bone marrow microenvironment, it is possible that some patients with multiple myeloma who relapse on thalidomide may present with extramedullary plasmacytomas, as seen in this case. Therefore, whenever symptoms arise in patients with multiple myeloma who are receiving thalidomide, extramedullary plasmacytomas should be considered.

The oral combination of thalidomide, cyclophosphamide and dexamethasone (ThaCyDex) is effective in relapsed/refractory multiple myeloma

We evaluate the efficacy of the oral combination of thalidomide, cyclophosphamide and dexamethasone (ThaCyDex) in 71 refractory/relapsed multiple myeloma patients, including a prognostic analysis to predict both response and survival. Patients received thalidomide at escalating doses (200-800 mg/day), daily cyclophosphamide (50 mg/day) and pulsed dexamethasone (40 mg/day, 4 days every 3 weeks). On an intention-to-treat basis and using the EBMT response criteria, 2% patients reached complete response (CR), 55% partial response (PR) and 26% minor response (MR) yielding a total response (CR+PR+MR) rate of 83% after 3 months of therapy. After 6 months of therapy, responses were maintained including a 10% CR. The 2-year progression free and overall survival were 57 and 66%, respectively. A favorable response was associated with beta2 microglobulin < or =4 mg/dl, platelets >80 x 10(9)/l and nonrefractory disease. Regarding survival, low beta2 microglobulin (< or =4 mg/dl), age (< or =65 years) and absence of extramedullary myelomatous lesion were associated with a longer survival. Major adverse effects included constipation (24%), somnolence (18%), fatigue (17%) and infection (13%). Only 7% of patients developed a thrombo-embolic event. ThaCyDex is an oral regimen that induces a high response rate and long remissions, particularly in relapsing patients with beta2 microglobulin < or =4 mg/dl and < or =65 years.

Treatment of plasma cell dyscrasias with thalidomide and its derivatives

PURPOSE

In 1999, investigators reported promising results of a phase II study of thalidomide in patients with resistant multiple myeloma (MM). Since then, various trials of thalidomide alone and in combination with other agents have been tested in patients with resistant and, more recently, untreated MM. In addition, preliminary results of phase I studies of the immunomodulatory derivatives (IMiDs) of thalidomide have been recently reported.

DESIGN

We reviewed and report the results of clinical trials of thalidomide and the IMiDs, as well as the pharmacology, mechanism of action, and toxicity of these agents.

RESULTS

Thalidomide has demonstrated significant activity in both resistant and previously untreated multiple myeloma. Combination therapy with dexamethasone increases response rate, even in patients previously resistant to both drugs given as single agents. More recent studies of thalidomide with dexamethasone in previously untreated patients are highly encouraging. The addition of chemotherapy to thalidomide and dexamethasone may further increase response rates, but its effect on patient survival has not been clarified. Preliminary results of trials of IMiD-3 indicate that this agent is active in resistant myeloma and has a toxicity profile different from that of thalidomide.

CONCLUSION

Many studies have confirmed the activity of thalidomide in MM, as well as an improved response with dexamethasone. Newer thalidomide derivatives with reduced toxicity (neuropathy, teratogenicity) are also promising. Thalidomide with dexamethasone may now represent the treatment of choice for previously untreated patients. Further studies with these and other novel agents early in the course of myeloma may improve complete remission rates and frequency of long-term control.