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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The absence of specific criteria for the definition of vertebral fracture has major implications for assessing the apparent prevalence and incidence of vertebral deformity. Also, little is known of the effect of using different criteria for new vertebral fractures in clinical studies. We therefore developed radiological criteria for vertebral fracture in women for assessing both the prevalence and the incidence of vertebral osteoporosis in population and in prospective studies and compared these with several other published methods. Normal ranges for vertebral shape were obtained from radiographs in 100 women aged 45-50 years. These included ranges for the ratios of anterior/posterior, central/posterior and posterior/predicted posterior vertebral heights from T4 to L5. The predicted posterior height was calculated from adjacent vertebrae. In contrast to other methods, our definition of fracture required the fulfillment of two criteria at each vertebral site, and was associated with a lower apparent prevalence of fracture in the control women due to a lower false positive rate. The prevalence and incidence of vertebral deformity using different criteria were then compared in a series of women with skeletal metastases from breast cancer in whom radiographs were obtained 6 months apart. The prevalence of vertebral deformity and the specificity for deformity varied markedly with differing criteria. Using a cut-off of 3 standard deviations the prevalence of vertebral deformity in the women with breast cancer was 46%. Using other methods, the prevalences of deformity ranged from 33% to 74%. Over a 6-month interval 25% of patients with breast cancer sustained 61 deformities using our method, of which only 8% resulted from errors in reproducibility. The number of patients sustaining new deformities was increased twofold when assessed by other methods (45%-53%), but errors of reproducibility may have accounted for 21% of the new deformities. The magnitude and distribution of these errors have important implications for the apparent therapeutic efficacy of agents in clinical trials of osteoporosis. The rapid semi-automated technique for assessing vertebral deformities on lateral spine radiographs that we have developed has a high specificity, and reduces the impact of errors of reproducibility on estimates of prevalence and incidence. The method should prove a value in assessing vertebral deformity both in population studies and in prospective clinical trials.
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PMID:The assessment of vertebral deformity: a method for use in population studies and clinical trials. 800 41

Five cadaveric pelves and 40 dry bony specimens were used to assess the feasibility of the lumbosacral plate fixation extending to beyond the S1 region and quantitatively to evaluate the posterior sacroiliac region and the dimensions of S1 and S2 pedicle and lateral mass. Partial removal of the posterior ilium was undertaken to measure the surface area available for plate fixation on the dorsal aspect of the sacrum. The results showed that the average distances between the outer edges of S1 and S2 dorsal foramina and the medial edge of the posterior ilium increased from 11.3 mm before removal of a portion of the medial posterior ilium to 16.6 mm after removal at the S1 level, and from 8.4 mm before removal of partial medial posterior ilium to 13 mm after removal at the S2 level, respectively. The average depths of the S1 and S2 pedicles were 37.1 and 32.2 mm in the direction anteromedial to the sagittal plane, respectively. The average depths of the S1 and S2 lateral mass were 37.3 and 33.9 mm in the direction anterolateral to the sagittal plane, respectively. In cases of vertebral metastases or osteoporosis, plating extending to S2 may be needed if good bony purchase cannot be achieved by the S1 pedicle or lateral mass screw. This study suggested also that partial removal of the posterior ilium enhances the space on the posterior aspect of the sacrum without severe compromise of the sacroiliac joint.
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PMID:Anatomic considerations for dorsal sacral plate-screw fixation. 856 54

Insufficiency fractures of the pelvis are commonly overlooked as causes of severe hip and low back pain. Predisposing factors include postmenopausal osteoporosis, corticosteroids, and local irradiation. Differential diagnosis includes metastatic disease to bone. We present the case of a 65-year-old woman who had a two-month history of low back pain and left groin pain. Her medical history included osteoporosis and endometrial cancer that was treated with radiation therapy to the pelvis 1 year prior to presentation. Despite bed rest, analgesics, and therapeutic modalities, her pain remained intractable and prevented ambulation. Plain radiographs showed no fracture. Computed tomography (CT) and magnetic resonance imaging showed fractures of the pelvis but were suggestive of malignancy. CT-guided bone biopsy was consistent with radiation osteonecrosis. After diagnosis and continued therapy, the patient progressed to ambulation with moderate discomfort. Failure to diagnose insufficiency fractures could lead to further pelvic irradiation, compromising already weakened bones and causing prolonged disability.
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PMID:Pelvic insufficiency fractures after irradiation: diagnosis, management, and rehabilitation. 860 69

Relaxation times of water were measured in human vertebral bodies by a fat-suppressed dual-echo turbo spin echo/turbo inversion recovery MRI sequence. Comparison was made with T1 and T2 values obtained by localized 1H-MR spectroscopy. The accuracy of the results and the diagnostic potential of the fast quantitative MRI technique were evaluated in 20 volunteers, 11 patients with osteoporosis, 6 patients with lymphoma, and 6 patients with bone marrow metastasis. No significant alterations of T1 and T2 relaxation times of water and fat were found in osteoporosis. With both methods, an increase in the T1 values of the water resonance by 16% was observed in lymphomas, which was highly significant (P < .001) in the MRS measurements, and an elevation by the same amount was obtained by the MRI sequence for the metastases (P = .040). A strong reduction of fat fraction was quantified by MRS in the tumorous cases. T2 of the water resonance increased by more than 30% (P < .003) in metastases. Water T2 values obtained by the MRI sequence showed systematic deviations from the MRS results, especially at short echo spacings.
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PMID:Determination of 1H relaxation times of water in human bone marrow by fat-suppressed turbo spin echo in comparison to MR spectroscopic methods. 872 21

Oestrogen levels play a major role in conditioning the rates of bone changes in women. Tamoxifen is a synthetic oestrogen antagonist commonly used as an adjuvant therapy for breast cancer. The goal of the present study was to study the amount and the elemental composition of bone minerals in the appedicular skeleton of women with breast cancer treated with adjuvant tamoxifen, as well as to investigate the possibility of increased risk for osteoporosis. Forty-two patients, aged 41-65 years, without skeletal metastases were studied. The mean duration of tamoxifen administration on a daily dose of 20 mg was 21 months (range 1-59 months). It was found that neither the amount of phosphorus in hands (HBP) nor forearm bone mineral content (BMC) differ statistically from those of age-matched healthy subjects. This was confirmed by reassessing bone mineral status after 30 months in 17 postmenopausal patients treated with tamoxifen for a mean time of 52 months. In conclusion, our data support that long-term tamoxifen treatment has no adverse or protective effect on the amount and elemental composition of the appedicular skeleton.
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PMID:Elemental composition of bone minerals in women with breast cancer treated with adjuvant tamoxifen. 875 May 83

The high prevalence of bone metastases in breast cancer and the risk that spinal and femoral osteoporosis may add further morbidity provide a rationale for bisphosphonate therapy in patients with skeletal metastases from mammary carcinoma. We investigated the effects of oral clodronate given during 9 months, with a 24-month follow-up, on bone mineral density (BMD), on biochemical markers of bone remodeling, and on osseous complications in 67 women with documented relapsing breast cancer, aged 58.7 +/- 1.5 years (x +/- SEM). Patients with active cancer disease were randomly allocated to two groups, with or without clodronate treatment (1600 mg/day, orally). Twenty-six women considered in complete remission (52.4 +/- 2.4 years) were also studied. Expressed in deviation from gender- and age-matched normals (z score), base-line BMD at the levels of lumbar spine (LS), femoral neck (FN), and midfemoral shaft (FS) was +0.10 +/- 0.22 vs. -0.12 +/- 0.25, +0.03 +/- 0.19 vs. -0.54 +/- 0.24, and +0.08 +/- 0.14 vs. -0.02 +/- 0.22, in patients with active breast cancer and in subjects in remission, respectively. After 9 months of treatment, fasting urinary calcium to creatinine ratio was lower (0.26 +/- 0.04 vs. 0.40 +/- 0.04 mmol/mmol creatinine, p < 0.02) and serum osteocalcin was stabilized (-2.1 +/- 1.1 vs. +7.0 +/- 3.3 micrograms/L, as compared with pretreatment values, p < 0.02), in the clodronate-treated group. The rate of osseous complications (pathological fracture, hypercalcemic episode, scintigraphic or radiological evidence of metastasis development, chemo- or radiotherapy for bone disease progression) was 28.8 events per 100 patient-year in the clodronate-treated group vs. 39.0 in controls, and 31.5 vs. 40.5, after 9 and 15 months of follow-up, respectively. In 15 women without evident LS bone metastasis (7 clodronate-treated and 8 controls), LS BMD increased in the clodronate-treated group by +5.2 +/- 2.5% vs. -0.3 +/- 1.4%, and +8.1 +/- 4.7 vs. -0.9 +/- 1.7, after 10.3 +/- 0.4 and 17.3 +/- 1.2 months, respectively (p < 0.01), as compared with pretreatment values. These results indicate that clodronate treatment decreased bone turnover and attenuated cancer-related bone morbidity. In addition, clodronate increased LS BMD in apparently unaffected bone of women with relapsing breast cancer.
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PMID:Effects of oral clodronate on bone mineral density in patients with relapsing breast cancer. 880 93

Metastatic bone cancer is usually diagnosed by graphical examinations. On plain x-ray film, it demonstrates osteolytic change with bone destruction in most cases, so sclerotic change without bone destruction is observed in some cases. In the spine metastases, it is important to differentiate compression fracture of the osteoporosis from the pathological destruction of the metastatic cancer. Although on plain x-ray film, the differentiation of these two conditions is difficult in most cases, MRI is useful to differentiate them. The treatment plan for metastatic bone cancer must be carefully decided. Systemic examinations and evaluation of the patient's general condition must be performed before treatment is started. There are conservative treatments such as chemotherapy, radiotherapy, hormone therapy and immune therapy, and operative treatment for metastatic bone cancer patients. Radiotherapy is useful for the pain caused by spinal cancer invasion. As a rule, operative treatment is indicated for the patients with the life expectancy of six months or more. But recently, with the progress of operative technique and implant material, more aggressive operative indication is proposed to improve the quality of life of the patients.
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PMID:[Diagnosis and treatment of metastatic bone cancer]. 883 37

Percutaneous vertebroplasty is a technique of interventional radiology, which allows to fulfill pathologic vertebral body with acrylic cement. This method is used to strengthen the vertebral body and reduce pain in some diseases involving the vertebra. Main indications are spine angiomas, metastases and osteoporosis. The vertebroplasty is realised under neuroleptanalgesia for cervical spine antero lateral way is used. For thoracic or lumbar vertebra, the way of approach is usually transpedicular; but in some cases, this approach is not possible: osteolysis of the pedicle, surgical osteosynthesis; in such cases, a postero lateral approach is realized. Technical incidents are not rare, but are usually asymptomatic. More frequent are venous filling with cement; the veins involved can be intra spinal (vertebral plexus) or paraspinal. Instead of this frequency pulmonary embolism in direct relation with the vertebroplasty where not reported. Extravasation in intervertebral disk or soft tissue can also be observed. This last incident can be in relation with the way of the needle or with a cortical rupture. Local complications are rare: rate of neurological deficit or infection is under 0.5%. Radicular pain is observed in 3.7% of cases. These complications are in close relation with the radiological involvement of the vertebra: cortical disruption, heterogeneous Lysis of the vertebral body. The frequency of complications is 1.3% in osteoporosis, 2.5% in spine angiomas and 10% in metastatic disease. Indications concern lesion involving the vertebral body: symptomatic spine angiomas; painful osteoporotic fractures after medical treatment or in patients with a high risk of decubitus complications; in metastatic disease, vertebroplasty is a way to consolidate the vertebral body and release pain. It can be usefull in recurrent pain after chemotherapy and/or radiotherapy, and also in unstable vertebra to obtain a stabilization before radiotherapic or chemotherapic treatment isolated or in combination with surgical osteosynthesis.
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PMID:[Percutaneous vertebral surgery. Technics and indications]. 930 44

In MRI of the skeleton, marrow edema is a frequent finding that can be caused by avascular necrosis, fracture, bone bruises, transient osteoporosis, osteomyelitis, primary tumors, metastases, and altered biomechanical properties. We examined a 29-year-old woman golfer with mild pain and swelling of the proximal phalanx II of the left hand. No signs of a stress fracture were seen on the MR images or plain radiographs. MRI revealed increased signal intensity on T2-weighted images in the metacarpal and proximal phalanx II in the left hand. We concluded that bone marrow edema may be the result of physiologic bone response to stress and may not necessarily correspond with severe trauma. Our case complements recent observations outlining the influence of altered biomechanics as a reason for marrow edema.
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PMID:Overuse edema in the bone marrow of the hand: demonstration with MRI. 944 56

Bisphosphonates (BPs) are pyrophosphate analogs in which the oxygen bridge has been replaced by carbon and diverse carbon side chains have generated a large family of compounds. Several are potent inhibitors of bone destruction (resorption) and are in clinical use for the treatment and prevention of osteoporosis, Paget's disease, hypercalcemia caused by malignancy, tumor metastases in bone, and other bone ailments. Selective action on bone is based on the binding of the BP moiety to the bone mineral. The molecular mode of action of BPs, which may differ from compound to compound, is unknown. However, at the tissue level, all BPs inhibit bone destruction and lead to an increase in bone mineral density by decreasing bone resorption and bone turnover. At the cellular level, the ultimate target of BP action is the osteoclast, the bone resorbing cell. In vitro evidence shows BP inhibition of osteoclast formation, via action on osteoblasts, and there is in vitro and in vivo evidence for BP inhibition of osteoclast activity. There is in vivo and in vitro evidence for increased apoptosis. The relative contribution of these various effects on the therapeutic action of BPs remains to be established. At the molecular level, it is not known if BPs act on a single or multiple targets. Enzymes in the cholesterol biosynthesis pathway and protein tyrosine phosphatases were shown to be inhibited by BPs.
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PMID:Mechanisms of action of bisphosphonates. 959 60


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