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.

UNASSIGNED: Multiple myeloma is a plasma cell neoplasm that is commonly associated with lytic bone lesions; however, osteosclerotic multiple myeloma is a rare entity. Osteosclerotic multiple myeloma has been reported in association with POEMS syndrome.
UNASSIGNED: A 60-year-old female patient presented to us with low back pain for 2 months. The investigations revealed that the patient had multiple osteosclerotic lesions in the axial skeleton with a L4 ivory vertebra. The serum immunoelectrophoresis was negative. Positron emission tomography scan was done which showed multiple skeletal lesions in the right iliac bone, left femoral neck, thoracic vertebrae T1, T6, T12, and lumbar vertebra L4. Biopsy and immunohistochemistry of the lesion showed plasma cell proliferation; producing lambda light chains. However, there were no features of POEMS syndrome including polyneuropathy, organomegaly, endocrinopathy, and skin changes. The patient was started on chemoradiation and achieved clinical remission and was asymptomatic at 12 months follow-up.
UNASSIGNED: Osteosclerotic myeloma without the features of POEMS syndrome is an extremely rare entity. This case reports documents a unique clinical scenario of osteosclerotic non-secretory light chain myeloma without POEMS syndrome.

Polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes (POEMS) syndrome, a form of osteosclerotic myeloma, is a multisystem disease related to a monoclonal plasma cell proliferative disorder. Osseous lesions are most commonly sclerotic on radiographs and computed tomography (CT), demonstrate low T1 and T2 signal intensity on magnetic resonance imaging (MRI), and have variable degrees of avidity on positon emission tomography (PET) imaging using 18-fluorodeoxyglucose (18F-FDG). We present three cases of POEMS syndrome manifesting as osteolytic lesions with indolent features, including well-defined thin sclerotic rims, no cortical disruption or periosteal reaction, no associated soft-tissue mass, and a periarticular location, all features that could lead to misinterpretation as benign bone lesions. We also report increased T1 signal and diffuse solid enhancement of these lesions on MRI, features previously unreported. POEMS syndrome should not be discounted as a diagnostic consideration in the setting of osteolytic lesions with non-aggressive imaging characteristics on radiographs or CT, especially in the presence of other supportive clinical features.

POEMS syndrome is a paraneoplastic disorder secondary to an underlying plasma cell dyscrasia. By definition, all patients with POEMS syndrome must display polyneuropathy and monoclonal plasma cell disorder. In addition, at least one major criterion (Castleman\'s disease, sclerotic bone lesions, or vascular endothelial growth factor elevation) and one minor criterion (organomegaly, extravascular volume overload, endocrinopathy, skin changes, papilledema, thrombocytosis, or polycythemia) are required for diagnosis. Treatment is based on extent of the disease. Radiotherapy is used for localized disease. Systemic therapy is required for disseminated disease, with bone marrow involvement by clonal plasma cells, or in patients who progress shortly after radiation. Upfront autologous stem cell transplantation is the treatment of choice for transplant-eligible patients. Outcomes are typically superior to that of standard myeloma. Herein, using a case vignette, we outline the latest evidence regarding the prognostication and management of POEMS syndrome, with a focus on its relapsing-remitting course.

Castleman disease (CD) most commonly affects lymphoid tissues in the thorax, abdomen, pelvis, and neck. Extralymphatic tissues, such as lacrimal glands, lung, pancreas, larynx, parotid, meninges, and even muscles, have also been reported as sites. The etiology is unknown and its incidence has not been reported in the literature. Castleman disease can be classified clinically into a unicentric or multicentric form, depending on the number of lymph nodes involved, and histologically into a hyaline vascular variant, plasma cell, mixed cellular, or plasmablastic variant. The disease has a predominantly inflammatory background, reflected in high levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6). The role of cytokines in CD explains the clinical presentation. The clinical scenario varies widely, based mainly on the histologic type. Unicentric CD usually presents without symptomatology, whereas multicentric manifests with fatigue, abdominal or thoracic pain, cytopenias, and/or B- symptoms (10% weight loss in the last six months, nocturnal diaphoresis, and fever). The endocrinopathy has a wide range of manifestations, affecting either the pituitary or other target organs. Achieving the diagnosis is complicated and there is no laboratory or imaging pathognomonic for this disease. The gold standard is an excisional biopsy from an affected lymph node. The treatment depends on the type of CD. Unicentric CD has a good response to excisional surgery. However, in multicentric CD (MCD), surgery may provide transient relief of symptoms but with a rebound effect, so it is not considered a good method. The use of chemotherapy, monoclonal antibodies, glucocorticoids, and thalidomide has shown some improvement in MCD.

BACKGROUND: POEMS syndrome, a rare paraneoplastic disease, is related to multiple organs, multiple systems, and multiple disciplines and can be mistaken for other disorders. Consequently, the diagnoses are often delayed. In this work we studied the clinicopathologic characteristics of the POEMS syndrome to improve early diagnosis to prevent irreversible damage.
METHODS: We conducted a clinicopathologic analysis of 9 cases of POEMS and made a differential diagnosis with related diseases.
RESULTS: The patients with POEMS syndrome were shown to have complicated clinical characteristics, including peripheral neuropathy, organomegaly, endocrinopathy, monoclonal plasma proliferative disorder, skin changes, extravascular volume overload, sclerotic bone lesions, thrombocytosis, and Castleman disease. POEMS syndrome shared many elements with other diseases and the key way to differentiate them was to determine whether there were other fundamental POEMS syndrome symptoms or signs. The level of M-protein in serum and plasma cells in bone marrow of POEMS patients was lower than that of patients with multiple myeloma (MM). Sclerotic bone lesions were a distinctive feature in patients with POEMS, compared with in those with MM.
CONCLUSIONS: Some unique clinicopathologic characteristics of POEMS syndrome can be used for differential diagnosis. This study provides increased awareness of POEMS syndrome.

OBJECTIVE: To assess the feasibility of volumetric intensity-modulated arc radiotherapy (VMAT) in patients with limited polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome.
METHODS: A 70-year-old male with histologically confirmed osteosclerotic myeloma was treated in our department in July 2010 with VMAT. Fourty-six Gray in 23 fractions were given on three bone lesions. Doses delivered to target volume and critical organs were compared with a tridimensional conformal radiotherapy (3D-RT) plan. Treatment was well tolerated without any side effects.
RESULTS: VMAT improved dose homogeneity within the target volume, as compared to 3D-RT (standard deviations: 2.9 Gy and 1.6 Gy for 3D and VMAT, respectively). VMAT resulted in a better sparing of critical organs. Dose delivered to 20% of organ volume (D20) was reduced from 22 Gy (3D-RT) to 15 Gy (VMAT) for small bowel, from 24 Gy (3D-RT) to 17 Gy (VMAT) for bladder and from 47 Gy (3D-RT) to 3 Gy (VMAT) for spinal cord. Volumes of critical organs that received at least 20 Gy (V20) were decreased by the use of VMAT, as compared to 3D-RT (V20 bladder: 10% vs 99%; V20 small bowel: 6% vs 21%). One year after treatment completion, no tumor progression has been reported.
CONCLUSIONS: VMAT improved dose distribution as compared to 3D-RT for limited osteosclerotic myeloma, with better saving of critical organs.