Radiotherapy is a definitive treatment for POEMS syndrome with solitary plasmacytoma. However, data on its efficacy and the role of immunochemotherapy are limited. This study evaluated the treatment outcomes for POEMS patients receiving radiotherapy as their primary therapy and compared the results of those treated with adjunctive immunochemotherapy with those without. A retrospective analysis of patients with POEMS syndrome referred to University College London Hospital from 1998 to 2023 was conducted. Amongst 150 POEMS patients, 30 (20%) presented with solitary plasmacytoma. Sixteen patients (53%) received radiotherapy alone, whilst 14 (47%) had combined treatment with radiotherapy and immunochemotherapy, predominantly lenalidomide and dexamethasone (Rd). Treatment responses were greater in the combined treatment group, with clinical, VEGF, haematological, and radiological responses of 100%, 92%, 100%, and 100% respectively, compared to 87%, 92%, 85%, and 79% in patients receiving radiotherapy only. The median follow-up for the entire cohort was 124 months, with a 5-year overall survival (OS) rate of 100% and progression-free survival (PFS) rate of 82%. For those receiving radiotherapy alone, the median follow-up was 124 months with a 3-year PFS rate was 69%. In contrast, no progression was observed amongst patients treated with combined therapy during the follow-up period (range 7-54 months). Six patients experienced disease progression, all having received radiotherapy alone as their first-line treatment. This study demonstrated the high efficacy of radiotherapy in patients with POEMS syndrome and solitary plasmacytoma and highlighted the potential benefits of combining radiotherapy with immunochemotherapy.
Lau et al. (Thu,) studied this question.