Abstract：
BACKGROUND: Multiple myeloma is a common plasma cell neoplasia usually accompanied by the formation of osteolytic foci, whereas osteosclerotic myeloma is a very rare form of plasma cell dyscrasia. When osteosclerotic myeloma is detected, osteosclerotic foci are usually part of the POEMS syndrome. Osteosclerotic myeloma without other manifestations of the POEMS syndrome is an unusual finding.
METHODS: In a 46-year-old woman, osteosclerotic changes of the temporoparietal region caused soft tissue induration over this lesion, which initiated further investigation. Imaging studies subsequently showed multiple osteosclerotic foci in the skull. Examination of blood proteins revealed 8 g/L of IgG-lambda monoclonal immunoglobulin, subclass IgG1. In search of the cause of the osteosclerotic changes, FDG-PET/CT was performed, which revealed no FDG accumulation, i.e., no other tumor (breast or stomach cancer). Low-dose CT showed irregular bone structure, but not significant osteolytic or osteosclerotic foci. To map the extent of osteosclerotic changes, NaF-PET/CT imagination followed, which revealed multiple spots with high fluoride accumulation. A parietal bone biopsy showed osteosclerosis with minor clonal plasma cell infiltration. Trepanobioptic bone marrow sampling revealed an infiltration of bone marrow with atypical plasma cells in 8%. Flow-cytometric examination of bone marrow showed 0,37% of plasma cells, however predominantly (91%) clonal with lambda expression. MRI of the brain identified asymptomatic meningeal thickening. There was no evidence of POEMS syndrome in the patient; thus, we concluded the diagnosis as monoclonal gammopathy of clinical significance with osteosclerosis which was previously termed osteosclerotic multiple myeloma.
CONCLUSIONS: Monoclonal gammopathy of clinical significance (MGCS) with osteosclerotic skeletal changes, documented on CT and multiple foci with intensive osteoneogenesis, documented on NaF-PET/CT without evidence of POEMS syndrome, is an extremely rare form of plasma cell dyscrasia. This publication documents the unique clinical manifestations of IgG-lambda type plasma cell proliferation without signs of POEMS syndrome and the role of NaF-PET/CT imaging. Classification of this disease as MGSC with osteosclerotic manifestations is more consistent with the indolent nature of the disease with a significantly better prognosis, compared with multiple myeloma.
METHODS: In a 46-year-old woman, osteosclerotic changes of the temporoparietal region caused soft tissue induration over this lesion, which initiated further investigation. Imaging studies subsequently showed multiple osteosclerotic foci in the skull. Examination of blood proteins revealed 8 g/L of IgG-lambda monoclonal immunoglobulin, subclass IgG1. In search of the cause of the osteosclerotic changes, FDG-PET/CT was performed, which revealed no FDG accumulation, i.e., no other tumor (breast or stomach cancer). Low-dose CT showed irregular bone structure, but not significant osteolytic or osteosclerotic foci. To map the extent of osteosclerotic changes, NaF-PET/CT imagination followed, which revealed multiple spots with high fluoride accumulation. A parietal bone biopsy showed osteosclerosis with minor clonal plasma cell infiltration. Trepanobioptic bone marrow sampling revealed an infiltration of bone marrow with atypical plasma cells in 8%. Flow-cytometric examination of bone marrow showed 0,37% of plasma cells, however predominantly (91%) clonal with lambda expression. MRI of the brain identified asymptomatic meningeal thickening. There was no evidence of POEMS syndrome in the patient; thus, we concluded the diagnosis as monoclonal gammopathy of clinical significance with osteosclerosis which was previously termed osteosclerotic multiple myeloma.
CONCLUSIONS: Monoclonal gammopathy of clinical significance (MGCS) with osteosclerotic skeletal changes, documented on CT and multiple foci with intensive osteoneogenesis, documented on NaF-PET/CT without evidence of POEMS syndrome, is an extremely rare form of plasma cell dyscrasia. This publication documents the unique clinical manifestations of IgG-lambda type plasma cell proliferation without signs of POEMS syndrome and the role of NaF-PET/CT imaging. Classification of this disease as MGSC with osteosclerotic manifestations is more consistent with the indolent nature of the disease with a significantly better prognosis, compared with multiple myeloma.
摘要：
背景：多发性骨髓瘤是一种常见的浆细胞瘤，通常伴有溶骨灶的形成，而骨硬化性骨髓瘤是一种非常罕见的浆细胞发育不良。当检测到骨硬化性骨髓瘤时，骨硬化灶通常是POEMS综合征的一部分。没有POEMS综合征的其他表现的骨硬化性骨髓瘤是一个不寻常的发现。
方法：在一名46岁的女性中，颞顶区域的骨硬化改变导致该病变的软组织硬结，展开了进一步调查。影像学检查随后显示颅骨有多个骨硬化灶。血液蛋白检查显示8g/L的IgG-lambda单克隆免疫球蛋白，IgG1亚类。为了寻找骨硬化变化的原因，进行FDG-PET/CT,这表明没有FDG积累，即，没有其他肿瘤（乳腺癌或胃癌）。低剂量CT显示骨结构不规则,但无明显溶骨或骨硬化灶。为了绘制骨硬化变化的程度，NaF-PET/CT想象力随之而来，揭示了多个高氟化物积累的斑点。顶骨活检显示骨硬化伴少量克隆浆细胞浸润。视神经骨髓取样显示骨髓浸润，非典型浆细胞占8％。流式细胞术检查骨髓显示有0.37%的浆细胞,然而，主要（91％）克隆与λ表达。脑部MRI发现无症状脑膜增厚。患者没有POEMS综合征的证据；因此，我们得出结论，诊断为具有临床意义的单克隆丙种球蛋白病，骨硬化以前称为骨硬化性多发性骨髓瘤。
结论：具有临床意义的单克隆丙种球蛋白病（MGCS）伴有骨硬化性骨骼改变，记录在CT和多个病灶与密集的骨生成，在NaF-PET/CT上记录，没有POEMS综合征的证据，是一种极其罕见的浆细胞发育不良。该出版物记录了IgG-λ型浆细胞增殖的独特临床表现，没有POEMS综合征的迹象以及NaF-PET/CT成像的作用。将该疾病分类为MGSC并伴有骨硬化表现，与该疾病的惰性性质更一致，预后明显更好。与多发性骨髓瘤相比。
方法：在一名46岁的女性中，颞顶区域的骨硬化改变导致该病变的软组织硬结，展开了进一步调查。影像学检查随后显示颅骨有多个骨硬化灶。血液蛋白检查显示8g/L的IgG-lambda单克隆免疫球蛋白，IgG1亚类。为了寻找骨硬化变化的原因，进行FDG-PET/CT,这表明没有FDG积累，即，没有其他肿瘤（乳腺癌或胃癌）。低剂量CT显示骨结构不规则,但无明显溶骨或骨硬化灶。为了绘制骨硬化变化的程度，NaF-PET/CT想象力随之而来，揭示了多个高氟化物积累的斑点。顶骨活检显示骨硬化伴少量克隆浆细胞浸润。视神经骨髓取样显示骨髓浸润，非典型浆细胞占8％。流式细胞术检查骨髓显示有0.37%的浆细胞,然而，主要（91％）克隆与λ表达。脑部MRI发现无症状脑膜增厚。患者没有POEMS综合征的证据；因此，我们得出结论，诊断为具有临床意义的单克隆丙种球蛋白病，骨硬化以前称为骨硬化性多发性骨髓瘤。
结论：具有临床意义的单克隆丙种球蛋白病（MGCS）伴有骨硬化性骨骼改变，记录在CT和多个病灶与密集的骨生成，在NaF-PET/CT上记录，没有POEMS综合征的证据，是一种极其罕见的浆细胞发育不良。该出版物记录了IgG-λ型浆细胞增殖的独特临床表现，没有POEMS综合征的迹象以及NaF-PET/CT成像的作用。将该疾病分类为MGSC并伴有骨硬化表现，与该疾病的惰性性质更一致，预后明显更好。与多发性骨髓瘤相比。
