Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027121 (myositis)
 4,538 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lymphoma can involve any part of the musculoskeletal system. Primary musculoskeletal lymphoma is rare but can occur in bone (reticulum cell sarcoma) or in the skin and subcutaneous tissues (mycosis fungoides). Secondary involvement in the musculoskeletal system is more common and can have a variety of radiologic findings. The definitive diagnosis of musculoskeletal lymphoma, however, is difficult to make by using imaging criteria alone. Any part of the musculoskeletal system can be involved and, therefore, a wide variety of primary and secondary neoplasms or inflammatory processes may have similar radiologic findings. The main differential diagnostic considerations, depending on the age of the patient and the clinical presentation, include osteosarcoma, Ewing's tumor, metastatic disease (from breast, lung, thyroid, or renal primary lesions), as well as chronic osteomyelitis or myositis. Primary and secondary bone lymphoma can be indistinguishable radiologically and histologically, but modern imaging techniques allow more accurate differentiation of primary from secondary bone involvement. This pictorial essay illustrates the CT findings of primary and secondary lymphoma involving bone, muscle, and skin and subcutaneous tissues.
 ...
PMID:Lymphoma of bone, muscle, and skin: CT findings. 837 91

Thigh pain is a serious condition in childhood and should be promptly and thoroughly investigated. Twenty-five cases of thigh pain lasting between 1 day and 7 months with mid-femoral periosteal thickening were analysed. There were 10 patients with Ewing's sarcoma, 7 with eosinophilic granuloma, 1 with osteoid osteoma, 1 with leukaemia, 3 with osteomyelitis, 1 with myositis and 2 with post-traumatic periosteal reaction. It was shown that patients with Ewing's sarcoma and eosinophilic granuloma have certain patterns of X-ray changes of high diagnostic value, which allow a proper diagnosis in most cases.
 ...
PMID:Unilateral mid-femoral periosteal newbone of varying aetiology in children. Radiographic analysis of 25 cases. 377 94

The value of new morphologic methods in the diagnosis of bone tumors is demonstrated in a number of cases. In round cell malignancies (Ewing's sarcoma, malignant lymphoma, neuroblastoma, and anaplastic plasmacytoma) diagnostic accuracy can be improved by electron microscopic and immunohistochemical techniques. New methods are also of value in differentiating the metastatic carcinoma from malignant bone primaries. Electron microscopy may show epithelial cell features (ie, gland structures, desmosomes, and tonofilaments), while immunohistologic investigation of the cytoskeleton may facilitate differentiation of epithelial cells (positive for prekeratin) from mesenchymal cells (positive for vimentin). In the differential diagnosis of typical bone tumors, however, such as osteosarcoma, chondrosarcoma, and malignant fibrous histiocytoma, the value of enzyme histochemical, electron microscopic, and immunohistochemical methods appears somewhat restricted: alkaline phosphatase activity may be increased in both chondrosarcoma and osteosarcoma; collagen type II, the cartilage-specific collagen, is found not only in chondrosarcoma but in osteosarcoma as well. Moreover, osteosarcomas may contain a considerable number of macrophages and histiocytes, and so this feature is worthless in distinguishing osteosarcoma from malignant fibrous histiocytoma. A new approach for appraising the malignancy of bone tumors may be through flow cytometric investigation of nuclear DNA content. Osteosarcomas reveal DNA aneuploidies in more than 80% of cases, with a large proportion of cells in the S phase. These features may prove valuable for discerning osteosarcoma from myositis ossificans. In contrast to typical giant cell tumor of bone, a rare case of malignant giant cell tumor showed aneuploid cell lines indicating the malignant nature of the tumor.
 ...
PMID:New cytomorphologic methods in the diagnosis of bone tumors: possibilities and limitations. 660 Jan 11

In 30 patients in whom osteomyelitis was suspected fine-needle bone biopsies (FNBB) were taken at the same time as bone was aspirated for bacteriological examination. The diagnosis of osteomyelitis was eventually confirmed in 15 patients; the other 15 had myositis (3), arthritis (3), trauma (2), microgeodic phalangeal syndrome (2), haematoma in a non-ossifying fibroma (1), and Ewing's sarcoma (1). In three patients no pathology was found. The temperature, WBC and ESR at presentation did not help to distinguish osteomyelitis from other conditions. FNBB, however, proved to be a useful additional investigation with a sensitivity for osteomyelitis of 87% and a specificity of 93%.
 ...
PMID:Fine-needle bone biopsy to diagnose osteomyelitis. 811

We report on a patient with a history of Ewing sarcoma who underwent surgery and subsequent adjuvant chemotherapy and radiotherapy. He developed low-back pain 6 months after the end of the radiotherapy and during consolidation chemotherapy. Magnetic resonance imaging showed evidence of myositis corresponding to the 'radiation-recall phenomenon', an inflammatory reaction of irradiated tissue.
 ...
PMID:Radiation-recall myositis presenting as low-back pain (2010: 4b). 2053 14

Radiation recall is a rare and poorly understood phenomenon, characterized by an acute inflammatory reaction within the previously irradiated area, triggered by a precipitating systemic agent. This reaction typically affects the skin, and radiation recall myositis in the absence of cutaneous involvement has rarely been described in the literature. In this report, we present two cases of radiation recall in pediatric Ewing sarcoma patients receiving successive proton radiotherapy and chemotherapy, with magnetic resonance imaging (MRI) of muscle edema within the prior radiation fields.
 ...
PMID:Radiation recall myositis in pediatric Ewing sarcoma. 2202 Nov 29

A 3-year-old boy presented with pathologic fracture of the left proximal femur. Magnetic resonance imaging revealed an aggressive expansile bony mass associated with cortical destruction and surrounding myositis. Computed tomography-guided biopsy revealed a monomorphic small round blue cell tumor by histology. CD99 immunoreactivity and low-level EWSR1 gene translocation by break-apart fluorescent in situ hybridization initially favored a diagnosis of Ewing sarcoma and chemotherapy commenced. Subsequent molecular evaluation by an anchored multiplex polymerase chain reaction-based assay (Archer FusionPlex Sarcoma Panel) revealed a nucleophosmin-anaplastic lymphoma kinase (NPM-ALK) gene fusion. The diagnosis was then amended to primary bone ALK-positive anaplastic large cell lymphoma and the chemotherapy regimen was modified accordingly. This report illustrates the value of this molecular assay in establishing the correct diagnosis of a very rare malignancy masquerading as another tumor type.
 ...
PMID:Primary Bone Anaplastic Large Cell Lymphoma Masquerading as Ewing Sarcoma: Diagnosis by Anchored Multiplex PCR. 2845 58