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

Abstract

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 1Á7% to 4Á5% and 7% to 34Á4% 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.

Multiple Extramedullary-Bone Related and/or Extramedullary Extraosseous Are Independent Poor Prognostic Factors in Patients With Newly Diagnosed Multiple Myeloma

“…Due to the lack of prospective research data, there is no standard recommended treatment for EMM patients at present; however, it is speculated that a combination of drugs with different mechanisms of action [such as lenalidomide-bortezomib-dexamethasone (RVD)] and ASCT might be an optimal approach ( 2 , 3 ). Patients with EMM should avoid the use of suboptimal induction therapy while focusing on adequate supportive care, especially in elderly patients.…”

“…The incidence of EMB is 6-35%, and the incidence of EME is 0.5-3.5%. Currently, there is not a precise definition of EMD and a lot of controversies (2,3); also, periods, inspection methods, and the detection rates of each report were different (2,(4)(5)(6)(7). In addition, there were limited data on the baseline characteristics of EMM, such as prevalence, clinical and laboratory characteristics, and the efficacy of new drugs.…”

Extramedullary Plasmacytomas of the Oral Cavity: A Case Report and Review of the Literature

“…In lesions where access for biopsy is not possible, magnetic resonance imaging or fluorodeoxyglucose (FDG)-positron emission tomography/CT (FDG-PET/CT) is recommended to assess the extent of soft-tissue disease. [2] In this case report, the patient had progression of his multiple myeloma despite multiple lines of therapy. The presence of multiple extramedullary plasmacytomas of the skin and oral cavity, revealing the haematogenous spread of clonal plasma cells, represented relapse of his disease and an overall poor prognosis.…”

Choosing the Right Therapy for Patients with Relapsed/Refractory Multiple Myeloma (RRMM) in Consideration of Patient-, Disease- and Treatment-Related Factors

“…In patients with known extramedullary disease or soft tissue plasmocytomas upon initiation of treatment, imaging-preferably via FDG-PET or MRI-is useful as a key diagnostic procedure [28,29]. Patients presenting with pain, neurological or other symptoms indicating the occurrence of, e.g., spinal cord compression by extramedullary disease or fractured osteolytic bone lesions need to receive immediate imaging.…”