POEMS syndrome with undetectable M-protein: a case report and literature review.

BACKGROUND: Polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome is a rare plasma cell (PC) neoplasm with associated paraneoplastic syndrome. According to the current diagnostic criteria, peripheral polyneuropathy and monoclonal PC proliferative disorder represent two mandatory criteria. CASE PRESENTATION: We report a 54-year-old male with peripheral neuropathy of bilateral lower limbs, sclerotic bone lesions, elevated vascular endothelial growth factor (VEGF) levels, splenomegaly, extravascular volume overload, endocrinopathy, and skin hemangiomas. Of note, serum and urine protein electrophoresis (PEP) and immunofixation electrophoresis (IFE) of this patient indicated undetectable M-protein and the normal ratio of free light chains κ and λ (FLC-R (κ/λ)). No monoclonal PCs were found in bone marrow examinations or biopsy of diseased bones. However, his clinical manifestations matched most of the diagnostic criteria. After excluding other diseases that are easily confused with POEMS syndrome, the diagnosis of variant POEMS syndrome with undetectable M-protein was proposed. The patient obtained clinically significant improvement and elevated VEGF returned to normal after 6 months of treatment with lenalidomide plus dexamethasone. CONCLUSIONS: Monoclonal PC dyscrasia (M-protein) while being a mandatory criterion for POEMS syndrome is undetectable in a considerable amount of patients that otherwise demonstrate typical symptoms. Here, we reported a case of variant POEMS syndrome with featured clinical manifestations, elevated VEGF levels, and good response to therapies targeting PCs but no evidence of M-protein. Therefore, negative results in M-protein and monoclonal PCs aren't enough to reject the diagnosis of POEMS syndrome. It is imperative to recognize the variant form of POEMS syndrome.

[A race against time: POEMS syndrome]. / "Verseny az idovel": a POEMS szindróma.

Background - POEMS syndrome is a potentially well manageable disease with an ascendant therapeutic arsenal nowadays. The early recognition of the syndrome is key to prevent serious multiorgan damage, and that is still a big challenge for physicians. With the following two case reports the authors aimed to highlight the consequences of late recognition of the disease and summarize the potential therapeutic options for POEMS syndrome.

Results - We have presented two patients’ cases with a long history of examination and treatment because of uncleared polyneuropathy. Through these cases we could see how serious could be the consequences of late diagnosis and despite multiorgan impairment there are still therapeutic options which could improve the patient’s condition. Although the diagnosis of POEMS syndrome is not easy, it must raise our mind the thought and be prudent when we start a treatment in polyneuropathy.

[POEMS Syndrome].

POEMS syndrome is a multisystem disorder associated with monoclonal plasma cell proliferation and the overproduction of vascular endothelial growth factors. The prognosis of POEMS syndrome has significantly improved owing to anti-myeloma treatments such as thalidomide and autologous stem cell transplantation. Therefore, early diagnosis and appropriate treatment are becoming increasingly important. A thorough and comprehensive evaluation of both systemic symptoms and laboratory abnormalities associated with the disease is essential for early diagnosis. The collaboration between neurology and hematology is indispensable to ensure proper treatment.

Detection of clonal plasma cells in POEMS syndrome using multiparameter flow cytometry.

POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein [M-protein], and skin changes) is a rare systemic disorder characterized by various symptoms caused by underlying plasma cell (PC) dyscrasia. Detection of monoclonal PCs is mandatory for the diagnosis of POEMS syndrome; however, the usefulness of EuroFlow-based next-generation flow cytometry (EuroFlow-NGF) in POEMS syndrome for detecting monoclonal PCs in bone marrow (BM) and the gating strategy suitable for flow cytometry study of POEMS syndrome remain unknown. We employed EuroFlow-NGF-based single-tube eight-color multiparameter flow cytometry (MM-flow) and established a new gating strategy (POEMS-flow) to detect the monoclonal PCs in POEMS syndrome, gating CD38 broadly from dim to bright and CD45 narrowly from negative to dim compared to MM-flow. MM-flow detected monoclonal PCs in 9/25 (36.0%) cases, including 2/2 immunofixation electrophoresis (IFE)-negative cases (100%). However, POEMS-flow detected monoclonal PCs in 18/25 cases (72.0%), including 2/2 IFE-negative cases (100%). POEMS-flow detected monoclonal PCs with immunophenotypes of CD19- in 17/18 (94.4%). In six cases where post-treatment samples were available, the size of the clones was significantly reduced after the treatment (P = 0.031). POEMS-flow can enhance the identification rate of monoclonal PCs in POEMS syndrome and become a valuable tool for the diagnosis of POEMS syndrome.

A case of POEMS syndrome comprising of a complicated diagnostic procedure: Case report.

RATIONALE: This article presents the case of a patient with recurrent chronic diarrhea and cachexia who was misdiagnosed, followed by a literature review to summarize the reasons for misdiagnosis of POEMS syndrome and the treatment strategies. PATIENT CONCERNS: The diagnosis and treatment of this patient suggest that with the improvement of M-protein detection levels, the diagnosis of patients with low M-protein levels, such as those with POEMS syndrome, has been greatly aided. DIAGNOSES: POEMS syndrome requires polyneuropathy and monoclonal plasma cell proliferation as mandatory diagnostic criteria. Therefore, patients presenting with polyneuropathy should routinely undergo M-protein testing and consider the possibility of POEMS syndrome. INTERVENTIONS: The patient, in this case, was treated primarily with relatively conservative immunomodulatory agents. OUTCOMES: During follow-up after treatment, the patient's diarrhea and malnutrition showed significant improvement. LESSONS SUBSECTIONS: POEMS syndrome has low clinical specificity and a high rate of misdiagnosis. However, once a definitive diagnosis is made, the treatment outcome is favorable.

A Multicenter Analysis of Clinical Features and Long-Term Outcomes of POEMS Syndrome in Korea.

BACKGROUND: POEMS syndrome is a rare form of plasma cell dyscrasia characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal proteins, and skin changes. Owing to its low incidence, there are few reports regarding this syndrome. This multicenter study included 84 patients diagnosed with POEMS syndrome in South Korea. METHODS: We retrospectively evaluated 84 patients diagnosed with POEMS syndrome at 8 hospitals in South Korea between January 2000 and October 2022. The clinical characteristics and treatment outcomes were analyzed. RESULTS: The median patient age was 53 years (range, 26-77 years), and 63.1% of the patients were male. All patients had peripheral neuropathy, and 81 (96.4%) had monoclonal plasma cell proliferation. Plasma vascular endothelial growth factor levels were available for 32 patients with a median of 821 pg/mL (range, 26-12,900 pg/mL). Other common features included skin changes (54.2%), volume overload (71.4%), and organomegaly (72.6%). Of the 84 patients, 75 received initial treatment (local radiotherapy, 6 [8.0%]; chemotherapy, 17 [22.7%]; both chemotherapy and local radiotherapy, 9 [12.0%]), upfront autologous stem cell transplantation (ASCT), 43 (57.3%; with induction chemotherapy, n = 12, 16.0%; without induction chemotherapy, n = 31, 41.3%). The median follow-up duration was 40.7 months. The 5-year overall survival (OS) was 78%, and the 5-year progression-free survival (PFS) was 55%. Patients who underwent upfront ASCT and were diagnosed after 2014 had a longer OS and PFS. CONCLUSION: The demographics of Korean patients with POEMS syndrome were similar to those reported previously. Because of the introduction of new treatment agents and the reduced rate of transplant-related mortality related to ASCT, the treatment outcomes of Korean patients with POEMS syndrome have improved in recent years.

What is the best treatment strategy before autologous peripheral blood stem cell transplantation in POEMS syndrome?

Autologous peripheral blood stem cell transplantation (aPBSCT) provides optimal outcomes in POEMS syndrome but the definition of the best treatment before aPBSCT remains to be defined because of the rarity of the disease and the heterogeneity of published case series. We collected clinical and laboratory data of patients with POEMS syndrome undergoing aPBSCT from 1998 to 2020 in ten Italian centers. The primary endpoint of the study was to evaluate the impact of prior therapies and mobilization regimen on outcome. We divided the patients into three groups: patients who did not receive any treatment before transplant (15 patients, group A: front-line), patients pre-treated with other agents (14 patients, group B) and patients treated with cyclophosphamide as their mobilizing regimen (16 patients, group C). The three groups did not show differences in terms of demographic and clinical characteristics. All 45 patients underwent aPBSCT after a high-dose melphalan conditioning regimen, with a median follow-up of 77 months (range, 37-169 months). The responses were not statistically different between the three groups (P=0.38). Progression-free and overall survival rates at 6 years were: 70% (95% confidence interval: 55-85%) and 91% (95% confidence interval: 82-99) 65%, respectively, and did not differ between the three groups. The cumulative incidence of transplant-related mortality and relapse was 4% and 36%, respectively. In conclusion, in a relatively large number of patients with POEMS syndrome, undergoing an autologous transplant, pre-treatment and disease status at transplant did not appear to have an impact on major transplant outcomes.

Regular assessment of serum vascular endothelial growth factor levels to monitor POEMS syndrome.

BACKGROUND: To investigate the utility of regular serum VEGF (sVEGF) levels assessment in the monitoring of POEMS syndrome. METHODS: We retrospectively reviewed data of 30 patients with POEMS syndrome whose sVEGF was tested regularly every 6 months. sVEGF levels after treatment were measured and correlated with disability (Overall Neuropathy Limitations Scale, ONLS), clinical impairment (measured with the modified Clinical Response Evaluation Scale, mCRES), and relapse-free survival. The ability of sVEGF to predict disease flares during remission and refractory disease was also analysed. RESULTS: Patients with normalised serum VEGF levels (< 1000 pg/ml) at 6 months showed prolonged relapse-free survival (at 3-year 94% for complete VEGF response, 57% partial, 0% none, p < 0.001) and greater later clinical improvement (median ΔmCRES complete VEGF response -5 vs partial -4, p = 0.019, and vs no VEGF response -2, p = 0.006). After remission, the sensitivity of 6-month sVEGF monitoring in predicting clinical relapse was 58% with a specificity of 100%. In patients refractory to treatment, the sensitivity in predicting further clinical worsening was 15%. In addition, in 25% of the patients in remission and 16% of those refractory to therapy, sVEGF levels only increased at the time of relapse. CONCLUSIONS: Regular sVEGF assessment is a valid biomarker in the prediction of disease reactivation in POEMS syndrome and was particularly useful during the phase of remission.

Long-Term Outcomes of Autologous Stem Cell Transplantation in Patients with Newly Diagnosed POEMS Syndrome.

POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome is a rare form of plasma cell dyscrasia often treated with high-dose chemotherapy and autologous stem cell transplantation (ASCT). ASCT has resulted in satisfactory and sustained therapeutic outcomes. However, a substantial number of patients eventually experience disease progression, requiring second-line treatment. Therefore, it would be of further benefit to identify patients who will acquire the best long-term survival after ASCT. The aim of this study was to fully reveal the outcomes of patients undergoing ASCT in a large series with long-term follow-up. Long-term outcomes of 239 patients with newly diagnosed POEMS syndrome undergoing ASCT at a single center were evaluated retrospectively. Rates of hematologic complete response (CRH) and vascular endothelial growth factor (VEGF) complete response (CRV) were 57.3% and 68.6%, respectively, with 90.5% of patients achieving an overall clinical response. At a median follow-up of 94 months, the 5-year overall survival (OS) rate was 92.8%, and the 5-year time to next-line treatment (TTNT) rate was 72.2% (median TTNT, 96 months). Patients achieving CRH (5-year TTNT rate, 82.5% versus 60.7%; P < .0001) or CRV (5-year TTNT rate 83.7% versus 54.2%; P < .0001) had better survival outcomes compared to non-CR group patients. Dual hematologic and VEGF complete responses carry further benefit for survival (median TTNT, 129 months versus 68 months; P < .0001). Seven cases of second primary malignancy were recorded, all of which were solid tumors. Front-line ASCT resulted in excellent long-term survival in patients with POEMS syndrome, with the best survival observed in those achieving dual hematologic and VEGF CRs.

Giant papillary hemangioma-A rare tumor with an exceptional size.

Papillary hemangioma (PH) is a recently described vascular tumor with a predilection for the skin of the head and neck. Histopathologically, it is characterized by a bland endothelial proliferation arranged in a papillary configuration, bearing resemblance to glomeruloid hemangioma seen in the context of polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes syndrome. The largest cutaneous PH reported to date measured 1.5 cm in greatest dimension. Here, we report a case of PH with an alarming size of 10 cm. We present this case to add to the limited literature on this rare tumor, highlight the histopathologic differences between PH and its mimics, and emphasize the variable nature of PH tumor size.

POEMS syndrome characterized by bone lesions: A case report.

RATIONALE: POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal paraproteinemia, and skin changes) syndrome is a rare clinical syndrome characterized by multiple peripheral neuropathies, hepatosplenomegaly, endocrine disorders, monoclonal paraproteinemia, and dermatosis. The main manifestations of POMES were nerve and skin changes, and bone disease was not reported. Here, we report a case of POEMS syndrome with the main manifestation of bone lesions. PATIENT CONCERNS: POMES is rare and its clinical manifestations are complex, making it difficult for patients to find the department they should visit. It is easy to miss diagnosis and misdiagnosis, delay the treatment time of patients, and affect the prognosis. DIAGNOSIS INTERVENTIONS: The patient was admitted to the gastroenterology department due to hepatic insufficiency. Multiple osteogenic changes were found by improved enhanced CT due to screening for causes of hepatic insufficiency, and spleen enlargement was indicated by abdominal ultrasound. Due to the involvement of multiple system problems, and follow-up of medical history, it was found that there was a history of discoloration of the distal limb in cold weather in the past 5 years. All things considered, it may be POMES. Further refinement of the bone marrow examination revealed active proliferation of granulocytes and erythrocytes. Bone marrow biopsy showed active hyperplasia, dominated by granulocytes. IFE showed IgA (type λ) and monoclonal myeloma (M) protein bands. To sum up, POMES diagnosis is considered. OUTCOMES: After the diagnosis is clear and the informed consent of the patient and his family is obtained, prednisone acetate is anti-inflammatory, lenalidomide is used to regulate immune function, liver and stomach protection treatment and bile secretion promotion are given. The patient reported improvement in liver function, significant improvement in overall and limb stiffness, and was discharged with improvement. LESSONS: Although bone lesions are not typically the main manifestation of POEMS syndrome, this diagnosis should be considered when this manifestation is combined with organ enlargement, skin changes, and peripheral neuropathy. In addition, the collection of medical history is crucial, when there is a clinical manifestation and auxiliary examination does not match, the idea should be expanded according to the relevant evidence, and finally make the corresponding diagnosis.

Small vessel platelet thrombosis in the peripheral nerves in POEMS syndrome.

INTRODUCTION/AIMS: Vascular thrombosis is prevalent among patients with polyneuropathy, organomegaly, endocrinopathy M-protein, and skin changes (POEMS) syndrome. The endothelial cells in the endoneurium are often hypertrophied and the lumen is frequently occluded. Consequent local hypoxia may increase vascular endothelial growth factor (VEGF), which induces hypercoagulation and vascular permeability. METHODS: This study presents two patients in the fifth decade of life, who had rare nerve biopsy findings of vascular occlusion mainly by platelets. Before the cases presented here, we encountered nine confirmed POEMS patients whose nerve biopsies did not show similar findings. RESULTS: A small artery and a vein were occluded, but no atherosclerotic changes were observed. The endothelial cells that adhered to the packed platelets lost their junctions. DISCUSSION: Platelet aggregation, degranulation, and ischemia may cause a loose endothelial barrier and leak proinflammatory cytokines, such as interleukin-12. This may increase production of VEGF and may cause nerve demyelination. Small vessel platelet thrombosis may contribute to the pathogenesis of this disorder.

POEMS syndrome: an unusual cause of exuberant callus formation.

Several growth factors are expressed in distinct temporal and spatial patterns during fracture repair. Together, they lead to angiogenesis-osteogenesis coupling and hence bone healing by callus formation. Of these growth factors, vascular endothelial growth factor is of particular interest because of its ability to induce neovascularisation (angiogenesis) and osteoclast invasion in soft callus. Hyperplastic callus can be seen in metabolic bone disease, endocrine disease and in patients with traumatic brain injury, but has not been described so far in polyneuropathy, organomegaly, endocrinopathy, M-protein, skin changes (POEMS) syndrome. This report is a case of POEMS syndrome with unusual presentation in the form of exuberant callus formation at fracture sites.

POEMS syndrome: Update on diagnosis, risk-stratification, and management.

DISEASE OVERVIEW: POEMS syndrome is a life-threatening condition due to an underlying plasma cell neoplasm. The major criteria for the syndrome are polyradiculoneuropathy, clonal plasma cell disorder, sclerotic bone lesions, elevated vascular endothelial growth factor, and the presence of Castleman disease. Minor features include organomegaly, endocrinopathy, characteristic skin changes, papilledema, extravascular volume overload, and thrombocytosis. DIAGNOSIS: The diagnosis of POEMS syndrome is made with three of the major criteria, two of which must include polyradiculoneuropathy and clonal plasma cell disorder, and at least one of the minor criteria. RISK STRATIFICATION: Because the pathogenesis of the syndrome is not well understood, risk stratification is limited to clinical phenotype rather than specific molecular markers. Risk factors include low serum albumin, age, pleural effusion, pulmonary hypertension, and reduced estimated glomerular filtration rate. RISK-ADAPTED THERAPY: For those patients with a dominant plasmacytoma, first-line therapy is irradiation. Patients with diffuse sclerotic lesions or disseminated bone marrow involvement should receive systemic therapy. Corticosteroids are temporizing, but alkylators and lenalidomide are the mainstays of treatment, the former either in the form of low-dose conventional therapy or as high-dose conditioning for stem cell transplantation. Thalidomide and bortezomib also have activity, but their benefit needs to be weighed against their risk of exacerbating the peripheral neuropathy. Daratumumab combinations also appear promising based on case series. Prompt recognition and institution of both supportive care measures and therapy directed against the plasma cell result in the best outcomes.

[Identification of transcriptional features and surface markers of plasma cell clones in POEMS syndrome by single-cell RNA sequencing].

POEMS syndrome is a rare monoclonal plasma cell disorder with unique symptoms distinct from other plasma cell neoplasms. To identify and find the transcriptional features of clonal plasma cells in POEMS syndrome (POEMS clones), single-cell RNA sequencing was performed on patient-derived bone marrow plasma cells. POEMS clones were identified in 5 out of 10 patients, and the proportions of POEMS clones in the plasma cells were markedly smaller than that of other plasma cell malignancies such as multiple myeloma and MGUS. The transcriptional features of POEMS clones differed from those of other plasma cell diseases, and representative MM-related oncogenes were not upregulated in POEMS clones. Notably, POEMS clones are negative for CD19 and express significantly lower MHC-II levels than normal plasma cells; thus, CD19- HLA-DRlo is confirmed as a useful marker to identify POEMS clones in patients. These findings unveil the unique features of POEMS clones and contribute to the understanding of the pathogenesis of POEMS syndrome.