2019/06/18 by Oliver Tomkins, Stephen Keddie, Michael P. Lunn +1 · 2 citations
Medicine · #Peripheral Neuropathies and Disorders #Platelet Disorders and Treatments #Autoimmune Bullous Skin Diseases
paper · pdf · doi:10.1111/bjh.16057
POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes) is a rare paraneoplastic phenomenon secondary to plasma cell dyscrasia. Treatment is aimed at the underlying plasma cell clone and its survival factors. Autologous stem cell transplantation (ASCT) is selected for patients who have multifocal skeletal disease and/or bone marrow involvement with adequate performance status (Dispenzieri, 2017). Because of the rarity of the disease, there are relatively few papers describing outcomes following ASCT. This analysis seeks to add further to the emerging evidence and elucidate prognostic factors. All patients attending the University College London Hospitals (UCLH) Centre for POEMS who had previously undergone ASCT were reviewed. Forty-two patients had undergone ASCT between 1998 and July 2018. Details are shown in Table 1. Disease status on admission for ASCT was used as the baseline. Response assessment was carried out at 3, 6 and 12 months, with a tailored frequency thereafter. The time to maximal vascular endothelial growth factor (VEGF), haematological, radiological and clinical responses were calculated, using previously published definitions (D’Souza et al, 2012). Anonymised data collection was covered by local policies. Median (range) follow-up time was 62·2 (6–226) months. Clinical response was observed in 38 patients. Three patients died and one patient did not have a discernible clinical response within the follow-up period. Haematological response was evaluable in 33 patients: 14 (33·3%) patients achieved complete response (HRCR,), seven (16·7%) patients achieved very good partial response (HRVGPR), three of whom could not be classified as HRCR because they had not undergone repeat bone marrow examination. Three (7·1%) patients achieved partial response (HRPR), whereas nine patients were classified as haematological non-responders (HRNR). Of the patients who were not assessable by haematological criteria, seven had solitary plasmacytomas and hence did not have bone marrow involvement, and two died before having repeat bone marrow examination. Regarding VEGF response, 23 of the 36 evaluable patients achieved complete response (VEGFCR), five patients partial response (VEGFPR) and seven patients had no response (VEGFNR). Average pre-ASCT VEGF was 4959 pg/ml, with values available for 29 patients. VEGF showed a significant reduction, to means of 489·5 pg/ml at 6 months and 330 pg/ml at 12 months post-ASCT (P < 0·001). Ten of 17 patients with fluorodeoxyglucose -avid disease underwent repeat scans. Seven patients achieved complete response (RCR) and three patients achieved partial radiological response (RPR). Neurological and functional responses were achieved in all but two patients during follow-up. Two deaths occurred before reassessment was possible. Median time to first observed clinical improvement was four months, with continued improvement sometimes seen for several years. Three patients were bed-bound prior to ASCT; all experienced a marked improvement in their mobility following therapy. One was able to mobilise with ankle foot orthoses only. There was a significant improvement in overall neuropathy limitation scores (Graham & Hughes, 2006), with a median pre-ASCT score of 6 (range 0–12) and post-ASCT score of 2 (range 0–8) (P < 0·01). Thirty-nine patients (92·9%) were still alive at the time of review. The one-year survival rate was 95·4% and five-year survival rate was 89·5% (Fig 1). Three patients (7·1%) had died. The first patient did not survive to discharge following ASCT and died from progressive POEMS features and recurrent hospital acquired pneumonia within two months of transplantation. The second patient died of unknown cause within two months of ASCT, following discharge and a period of uneventful recovery. Transplant-related mortality was therefore calculated as 2·4% (n = 2). The third patient developed worsening features of POEMS two years after transplantation and was treated with cyclophosphamide followed by melphalan. They subsequently developed myelodysplastic syndrome, a known complication (Przepiorka et al, 2007), which resulted in death at 6 years. Six patients relapsed (median time 39·2 months, range 9–78 months.). Progression-free survival (PFS) was 80·1%, with three deceased patients and five patients currently undergoing further systemic therapy. One-year and five-year PFS was 81·6% and 76·9% respectively (Fig 1). Of the patients who had a clinical relapse, all developed worsening neuropathy with recurrence of oedema. All but two patients received lenalidomide and dexamethasone for their relapse. One patient received carfilzomib and dexamethasone due to a myelomatous phenotype and a higher marrow burden. Univariate analysis of relapsed versus non-relapsed patients showed absence of HRCR to be significant (P = 0·027). No patients who achieved HRCR following ASCT subsequently relapsed, whereas those with persisting monoclonal plasma cells or monoclonal protein had a 31·6% relapse rate. Age, VEGF, albumin and functional status were not statistically different between patients in remission and those who had relapsed. To our knowledge, this is the first paper detailing the experience of ASCT for POEMS syndrome at a UK centre. This analysis confirms high rates of overall survival and PFS following transplantation (Karam et al, 2015; Kourelis et al, 2016a; Cook et al, 2017; Ohwada et al, 2018; D'Souza et al, 2012). Our experience confirms that attainment of HRCR following ASCT in POEMS syndrome is associated with a significantly lower rate of relapse (Kourelis et al, 2016b; Wang et al, 2017; Ohwada et al, 2018). The median time to confirmed HRCR was 5·5 months, demonstrating that the success of ASCT can often be determined soon after therapy and allows for early relapse risk stratification. Our work carries the limitations of retrospective analysis and is susceptive to some inter-rater variation in terms of clinical response. Further work is required to ascertain whether maintenance following ASCT has a role in patients who do not achieve HRCR. Prolonged disease remission and substantial recovery is possible in the majority of cases post-ASCT, but its optimisation is critical to improve outcomes for more patients. More informative, readily applicable tools are needed to guide therapeutic decision-making, specifically the optimum depth of response before and after ASCT and biomarkers that have prognostic significance. In the current era of emerging novel therapies, clinical trials of alternative or adjuvant approaches to ASCT would be of considerable benefit to patients affected by POEMS syndrome. MPL is supported by the Biomedical Research Centre of University College London Hospitals NHS Foundation Trust. SK is supported by the Association of British Neurologist and the Guarantors of Brain [grant number 541665]. OT and SK collected data. OT analysed data and drafted the letter. All authors were responsible for interpretation of results, and revisions and edits. All authors agreed to be accountable for the work and provided final approval.