Extramedullary myeloma spread triggered by surgical procedures: an emerging entity?

Extramedullary disease in multiple myeloma: a systematic literature review

Extramedullary involvement (or extramedullary disease, EMD) represents an aggressive form of multiple myeloma (MM), characterized by the ability of a clone and/or subclone to thrive and grow independent of the bone marrow microenvironment. Several different definitions of EMD have been used in the published literature. We advocate that true EMD is restricted to soft-tissue plasmacytomas that arise due to hematogenous spread and have no contact with bony structures. Typical sites of EMD vary according to the phase of MM. At diagnosis, EMD is typically found in skin and soft tissues; at relapse, typical sites involved include liver, kidneys, lymph nodes, central nervous system (CNS), breast, pleura, and pericardium. The reported incidence of EMD varies considerably, and differences in diagnostic approach between studies are likely to contribute to this variability. In patients with newly diagnosed MM, the reported incidence ranges from 0.5% to 4.8%, while in relapsed/refractory MM the reported incidence is 3.4 to 14%. Available data demonstrate that the prognosis is poor, and considerably worse than for MM without soft-tissue plasmacytomas. Among patients with plasmacytomas, those with EMD have poorer outcomes than those with paraskeletal involvement. CNS involvement is rare, but prognosis is even more dismal than for EMD in other locations, particularly if there is leptomeningeal involvement. Available data on treatment outcomes for EMD are derived almost entirely from retrospective studies. Some agents and combinations have shown a degree of efficacy but, as would be expected, this is less than in MM patients with no extramedullary involvement. The paucity of prospective studies makes it difficult to justify strong recommendations for any treatment approach. Prospective data from patients with clearly defined EMD are important for the optimal evaluation of treatment outcomes.

Research progress on treatment of extramedullary multiple myeloma

ABSTRACTObjectives: Extramedullary multiple myeloma (EMM) is a relatively less frequent subentity of multiple myeloma (MM) and is generally considered to be a poor prognostic factor. Novel agents and hematopoietic stem cell transplantation (HSCT) have led to a significant improvement in the progression-free survival and overall survival of patients with MM, but outcomes of EMM remain dismal. Little is known regarding the role of novel therapies in this setting. This review summarizes the current available data regarding the roles of proteasome inhibitors, immunomodulators, monoclonal antibodies, chimeric antigen receptor (CAR)-T cell therapy and HSCT in EMM.Methods: A systematic literature review through PubMed was conducted to summarize the published evidence on the therapeutic developments of novel agents and HSCT in EMM. Literature sources published in English were searched, using the terms multiple myeloma, extramedullary and treatment.Results: Long-term outcomes of EMM patients remain dismal despite the utilization of novel agents and HSCT. The standard therapy of EMM has not been established. EMM should be managed as high-risk disease and treated accordingly.Discussion and conclusion: This review will provide an insight on the current and emerging treatment strategies as well as their efficacy in EMM. Further subgroup analyses in large prospective trials focusing on EMM is needed to help optimize the therapy.

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.

Outside the box-Surgery for aggressive plasmacytoma in scar

This report introduces the concept of large-scale surgery and reconstruction when all other medical means of treatment have failed. In select cases, this may act as a mode of buying time and allowing the patient to receive second- or third-line treatments.

Impact of extramedullary disease in patients with newly diagnosed multiple myeloma undergoing autologous stem cell transplantation: a study from the Chronic Malignancies Working Party of the EBMT

We investigated extramedullary disease in newly diagnosed multiple myeloma patients and its impact on outcome following first-line autologous stem cell transplantation. We identified 3744 adult myeloma patients who received up-front single (n=3391) or tandem transplantation (n=353) between 2005 and 2014 with available data on extramedullary involvement at diagnosis. The overall incidence of extramedullary disease was 18.2% (n=682) and increased per year from 6.5% (2005) to 23.7% (2014). Paraskeletal involvement was found in 543 (14.5%) and extramedullary organ involvement in 139 (3.7%). More patients with extramedullary organ involvement had multiple involved sites (≥2; P<0.001). In a comparison of patients with single sites with patients without the disease, up-front transplantation resulted in at least similar 3-year progression-free survival (paraskeletal: P=0.86, and extramedullary organ: P=0.88). In single paraskeletal involvement, this translated less clearly into worse 3-year overall survival (P=0.07) while single organ involvement was significantly worse (P=0.001). Multiple organ sites were associated with worse outcome (P<0.001 and P=0.01). First-line treatment with tandem compared with single transplantation resulted in similar survival in patients with extramedullary disease at diagnosis (P=0.13 for both).

Tooth Extraction Locally Stimulates Proliferation of Multiple Myeloma in a Patient with Mandibular Localizations

OBJECTIVES

Multiple myeloma (MM) is characterized by the occurrence of osteolytic lesions. MM treatment usually involves antiresorptive drugs (mainly bisphosphonates).

CASE REPORT

A patient with an MM presented osteolytic lesions of the mandible. Extraction of teeth 45 and 46 was performed 5 years after the diagnosis of periodontitis. Four months later, osteonecrosis of the jaw (ONJ) was diagnosed at the extraction site. X-ray showed an extension of osteolytic lesions on the right side, close to the extraction site, without modification of the lesions on the left side. Two months later, a curettage was performed because of a painful bone sequestration. X-ray showed an extension of the osteolytic lesions on the right side.

RESULTS

Histological analysis found a vascularized plasmacytoma of the soft tissues around the ONJ. Analysis of the bone showed mixed lesions with osteonecrotic areas and living bone resorbed by active osteoclasts surrounding a plasmacytoma. The surface area of the osteolytic foci has considerably increased only close to the extraction site.

CONCLUSIONS

Tooth extraction triggered an ONJ associated with bisphosphonate treatment. However, it also seemed to induce a considerable proliferation of plasma cells at the extraction site; we hypothesize that it is due to the increase in bone remodeling related to the surgical trauma.

Cytogenetics in multiple myeloma patients progressing into extramedullary disease

BACKGROUND

Extramedullary disease in multiple myeloma patients is an uncommon event occurring either at the time of diagnosis, or during disease progression/relapse. This manifestation is frequently associated with poor outcome and resistance to treatment. We evaluated chromosomal alterations of plasma cells of multiple myeloma patients with extramedullary relapse, either in the bone marrow (BM) or at extramedullary sites, and in previous BM collection by interphase fluorescence in situ hybridization.

MATERIAL AND METHODS

Thirty-one patients [25 BM plasma cells (BMPCs), 18 extramedullary tumor plasma cells], of which 12 had paired samples of BM and extramedullary plasma cells and 14 had previous collection of BM, were investigated for the presence of chromosomal aberrations (CHAs): del(17)(p13), del(13)(q14), 14q32 disruption, t(4;14)(p16;q32), t(14;16)(q32;q23), gain(1)(q21), and hyperdiploidy status.

RESULTS

Overall, in unrelated samples, t(4;14) was more prevalent in extramedullary plasma cells, and hyperdiploidy was more frequent in BMPCs. In paired samples, there was a higher frequency of del(13)(q14) and 14q32 disruption in BMPCs. Frequency of all studied CHAs was higher in BMPCs of extramedullary patients than in their previous sample collection.

CONCLUSION

These data show that plasma cells harbor more aberrations during their transformation into extramedullary form.