Osteoblastoma of dorsal spine: a case report. (1/52)

A case of benign osteoblastoma affecting posterior element of spine with pain and paraplegia in a female is being presented with brief review of literature. Early diagnosis and surgical excision remains the mainstay of treatment.  (+info)

Benign osteoblastoma mimicking malignancy of the spine. (2/52)

A case of osteoblastoma of the spine in a sixty year old female is presented. These lesions usually get misdiagnosed as tuberculosis or malignancy of the spine. Salient diagnostic features have been discussed.  (+info)

Skeletal changes in rats given daily subcutaneous injections of recombinant human parathyroid hormone (1-34) for 2 years and relevance to human safety. (3/52)

Fischer 344 rats (60/sex/group) were given daily subcutaneous injections of recombinant human parathyroid hormone (PTH)(1-34) for 2 years at doses of 0, 5, 30, or 75 microg/kg. Treatment caused substantial increases in bone mass consistent with the known pharmacologic effects of once-daily administration. As determined by quantitative computed tomography (QCT) and histomorphometry, bone mass was markedly increased. Substantial new bone formation resulted in a large decrease in marrow space accompanied by altered bone architecture. Bone proliferative lesions were observed in all PTH( 1-34)-treated groups. Osteosarcoma occurred in 3, 21, and 31 male rats and in 4, 12, and 23 female rats in the 5-, 30-, and 75-microg/kg treatment groups, respectively. Focal osteoblast hyperplasia, osteoma, and osteoblastoma were much less frequent. Although the specific cellular or molecular mechanisms responsible for the rat bone tumors have not been fully elucidated, the data suggest that these lesions resulted from the long duration of treatment and the exaggerated pharmacologic response of the rat skeleton to daily treatment with PTH(1-34). Important differences between the rat study and clinical use in adult humans suggest that the increased incidence of bone neoplasia in rats treated for 2 years is likely not predictive of an increased risk of bone cancer in skeletally mature adult humans being given PTH(1-34) for a limited period of time in the treatment of osteoporosis.  (+info)

MR imaging features of pigmented villonodular synovitis of the cervical spine. (4/52)

Pigmented villonodular synovitis (PVNS) is a benign proliferative disorder primarily occurring in the large joints of the appendicular skeleton such as the knee and hip joints. We present an unusual case of PVNS involving the cervical spine in an adult. MR imaging showed an enhancing mass lesion arising from the posterior elements of the cervical spine and hyperintensity on the T2-weighted images, without evidence of T2 susceptibility effects. Gross total excision of the tumor was performed, and the diagnosis was established by histopathology.  (+info)

Progression of a lumbar spinal osteoblastoma. (5/52)

A 24-year-old woman presented with a lumbar spinal osteoblastoma manifesting as a 5-year history of low back pain radiating to the left foot. Neuroimaging showed suspicious hypertrophy of the left L4-5 facet which transformed in 3 years to an expansile mass lesion that compressed the dura mater and neural structures. Primary benign bone tumors such as osteoblastoma and osteoid osteoma should be considered in the differential diagnosis of back pain and the patients should be followed up carefully.  (+info)

Bisphosphonates for treatment and prevention of bone metastases. (6/52)

Bone metastases are a major cause of morbidity for men with prostate cancer. Complications of bone metastases include pain, fractures, and spinal cord compression. Although they appear osteoblastic by radiographic imaging, most bone metastases are characterized by excess osteoclast number and activity. In addition, pathologic osteoclast activation is associated with increased risk of skeletal complications. Zoledronic acid, a potent inhibitor of osteoclast activity, differentiation, and survival, decreases the risk of skeletal complications in men with androgen-independent prostate cancer and bone metastases. Other bisphosphonates, including pamidronate and clodronate, seem to be ineffective in this setting. The reduction in risk of skeletal complications with zoledronic acid must be weighed against potential adverse effects. Additional studies are needed to determine the optimal timing, schedule, and duration of treatment in men with bone metastases as well as the potential role of bisphosphonates in other settings including the prevention of bone metastases.  (+info)

A complementary method for the detection of osteoblastic metastases on digitized radiographs. (7/52)

PURPOSE: This study was conducted to evaluate the diagnostic usefulness of gray level parameters in order to distinguish healthy bone from osteoblastic metastases on digitized radiographs. MATERIALS AND METHODS: Skeletal radiographs of healthy bone (n = 144) and osteoblastic metastases (n = 35) were digitized using pixels 0.175 mm in size and 4,096 gray levels. We obtained an optimized healthy bone classification to compare with pathological bone: cortical, trabecular, and flat bone. The osteoblastic metastases (OM) were classified in nonflat and flat bone. These radiological images were analyzed by using a computerized method. The parameters (gray scale) calculated were: mean, standard deviation, and coefficient of variation (MGL, SDGL, and CVGL, respectively) based on gray level histogram analysis. Diagnostic utility was quantified by measurement of parameters on healthy and pathological bone, yielding quantification of area under the receiver operating characteristic (ROC) curve, AUC. RESULTS: All three image parameters showed high and significant values of AUC when comparing healthy trabecular bone and nonflat bone OM, showing MGL the best discriminatory ability (0.97). As for flat bones, MGL showed no ability to distinguish between healthy and flat bone OM (0.50). This could be achieved by using SDGL or CVGL, with both showing a similar diagnostic ability (0.85 and 0.83, respectively). CONCLUSION: Our results show that the use of gray level parameters quantify healthy bone and osteoblastic metastases zones on digitized radiographs. This may be helpful as a complementary method for differential diagnosis. Moreover, our method will allow us to study the evolution of osteoblastic metastases under medical treatment.  (+info)

Utility of immunohistochemical analysis for cyclo-oxygenase 2 in the differential diagnosis of osteoblastoma and osteosarcoma. (8/52)

AIMS: To study the immunoexpression of cyclo-oxygenase (COX) 2 in osteoblastomas (OBs) and osteosarcomas (OSs), and to assess the utility of immunohistochemical analysis for COX 2 in the differential diagnosis of the two tumour forms. METHODS: The immunohistochemical features of COX 2 were studied in 11 OBs and 30 OSs, including 26 high-grade OSs (16 osteoblastic, 7 chondroblastic, and 3 fibroblastic) and 4 low-grade OSs. RESULTS: Tumour cells from all 11 OBs unequivocally showed diffuse, intense and cytoplasmic immunoreactivity for COX 2. Strong cytoplasmic expression of COX 2 was observed in 5 of 26 (19%) high-grade OSs, all chondroblastic. In one osteoblastic-type OS, COX 2 was expressed in the chondroblastic component, but this tumour was considered to be COX 2 negative. No COX 2 expression was noted in atypical osteoblastic cells. Staining in the four low-grade OSs was negative. CONCLUSION: The results of immunohistochemical analysis of COX 2 suggest that in addition to the routine histopathological evaluation, COX 2 is a valuable diagnostic marker in the distinction between OB and OS.  (+info)