Pathological Fracture Caused by Vascular Endothelial Cell Hemangioma-like Hyperplasia in POEMS Syndrome

POEMS syndrome is a rare paraneoplastic syndrome secondary to plasma cell dyscrasia. Osteosclerotic bone lesion is a characteristic change seen in POEMS syndrome, whereas pathological fracture is rare. Monoclonal l plasmacytoma may be the main pathological change responsible for bone lesions in patients with POEMS syndrome. In this study, we describe a patient who presented with a pathological fracture. Bone pathology indicated hemangioma-like vascular endothelial cell hyperplasia. To the best of our knowledge, this is the second report of pathological fracture caused by POEMS syndrome and the first report of pathological fracture caused by hemangioendothelioma-like changes in a patient with POEMS syndrome. A 55-year-old woman was hospitalized in August 2013 for severe pain in her left leg. An x-ray revealed a pathological fracture with an osteolytic lesion on the distal left femur and a sclerotic lesion on the proximal right femur (Figure 1A). Splenomegaly, ascites, skin hyperpigmentation and hemangiomas, multiple enlarged lymph nodes and elevated serum creatinine (228 mmol/L, normal range, 70–110 mmol/L) were found. Serum immunoglobulin assay yielded the following results: immunoglobulin A (IgA), 2.23 g/L (normal range, 0.82–4.53 g/L); IgG, 9.63 g/L (normal range, 7.51–15.6 g/L) and IgM, 1.37 g/L (normal range, 0.4–2.74 g/L). The monoclonal M-protein (IgA, l) was detected on serum immunofixation, but not through serum electrophoresis and urine immunofixation. Endocrine investigations revealed an increase in thyroid-stimulating hormone (11.9 mIU/L, normal range, 0.34–5.6 mIU/L) and a decrease in free triiodothyronine (3.38 pmol/L, normal range, 4.36–6.23 pmol/L). Bone marrow biopsy and aspiration were negative for plasma cells. The patient exhibited no symptoms of peripheral neuropathy, but electromyography examination showed symmetric peripheral nerve defects in both lower extremities. Pathology of lymph nodes indicated hyaline-vascular type Castleman’s disease (CD). Biopsy of the distal left femur revealed dramatic glomeruloid-like vascular endothelial cell hyperplasia, which was similar to the pathological changes observed in hemangiomas (Figure 1; panels B1, B2 and B3). No plasmacyte infiltration was found. Immunohistochemical findings were positive for the presence of human soluble adhesion molecules (SMA), CD34 and negative for CD38 and CD138. Kidney pathology showed diffuse mesangial cell and capillary proliferation in the glomerulus, with eosinophilic material deposits. Plasma vascular endothelial growth factor (VEGF) was higher than normal (898 pg/mL, normal level ,145 pg/mL). POEMS syndrome was diagnosed. Interlocking intramedullary nail internal fixation of the fracture was performed and chemotherapy was given (lenalidomide, 15 mg/d, days 1–21; dexamethasone, 40 mg, once weekly in a 28-day