Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presence of bone metastases predicts the presence of pain and is the most common cause of cancer-related pain. Although bone metastases do not involve vital organs, they may determine deleterious effects in patients with prolonged survival. Bone fractures, hypercalcaemia, neurologic deficits and reduced activity associated with bone metastases result in an overall compromise in the patient's quality of life. A metastasis is a consequence of a cascade of events including a progressive growth at the primary site, vascularization phase, invasion, detachment, embolization, survival in the circulation, arrest at the site of a metastasis, extravasion, evasion of host defense and progressive growth. Once cancer cells establish in the bone, the normal process of bone turnover is disturbed. The different mechanisms responsible for osteoclast activation correspond to typical radiologic features showing lytic, sclerotic or mixed metastases, according to the primary tumor. The release of chemical mediators, the increased pressure within the bone, microfractures, the stretching of periosteum, reactive muscle spasm, nerve root infiltration and compression of nerves by the collapse of vertebrae are the possible mechanisms of malignant bone pain. Pain is often disproportionate to the size or degree of bone involvement. A comprehensive assessment including a trusting relationship with the patient, taking a careful history of the pain complaint, the characteristics of the pain, the evaluation of the psychological status of the patient, neurological examination, the reviewing of diagnostic studies and laboratory findings, and individualization of the therapeutic approach, should precede any treatment. Radiotherapy is the cornerstone of the treatment. Low doses given in a single session are safe and effective, and reduce distress and inconvenience associated with repeated session. Radioisotopes are more imprecise in delivering specific doses of radiation, but have less toxicity and easy administration as well as effectiveness in subclinical sites of metastases, although storage, dispensing and administration should be under strict control. Chemotherapy and endocrine therapy are difficult to measure in terms of pain relief. Prophylactic fixation surgery can lead to improved survival and quality of life of patients with bone metastases. Surgical treatment should be undertaken when fracture occurs. Careful selection of patients for surgical spinal decompression is required. The potential benefits of surgical interventions have to be tempered with patient survival. The use of analgesics according to the WHO ladder is recommended. There is no clear evidence that non-steroidal anti-inflammatory drugs (NSAIDs) have a specific efficacy in malignant bone pain. The difficulty with incident pain is not a lack of response to systemic opioids, but rather that the doses required to control the incidental pain produce unacceptable side-effects at rest. Alternative measures are often required. The inhibition of bone resorption and hypercalcaemia can be reduced by the use of bisphosphonates. This class of drugs potentiate the effects of analgesics in improving metastatic bone pain. Invasive techniques are rarely indicated, but may provide analgesia in the treatment of pain resistant to the other modalities. Neural blockade should never be used as the sole modality for malignant bone pain, but should be considered as a helpful in specific pain situations. Careful appraisal and the application of a correct approach should enable the patient with bone metastases to obtain an acceptable pain relief despite the advanced nature of their malignant disease.
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PMID:Malignant bone pain: pathophysiology and treatment. 906 7

We recently encountered a case with local recurrence of malignant fibrous histiocytoma (MFH) in the bone after wide resection, caused by minute intravenous tumor emboli which were retrospectively detected in MR imaging. The patient was a 69-year-old woman who initially noticed a mass in her left thigh. The tumor was diagnosed to be MFH, therefore a wide resection was performed; although the tumor was closely attached to the periosteum, it was not difficult to dissect the tumor subperiosteally from the cortex of the femur. The patient received postoperative brachytherapy, but no chemotherapy. Two years later, the tumor recurred with bony destruction of the femur. We reviewed the pre-operative films obtained by various imaging modalities, as well as the histology of the primary tumor, and found minute intravenous tumor emboli in the MR imaging obtained before surgery. Tumor emboli were also observed histologically in the small vessels of the surgically resected tumor. Such intravenous tumor emboli have recently been implicated in the development of regional bone metastasis near the site of the primary lesion in cases of malignant soft tissue tumors. Therefore, we concluded that the tumor recurrence in our case was caused by small tumor emboli invading the perforating veins of the femur. It is therefore emphasized that MR images should be carefully reviewed for the presence of such intravenous tumor emboli before surgery in cases of high-grade malignant sarcomas. As at the time of writing, our patient remains alive and disease-free, with no evidence of any local recurrence or distant metastasis after wide tumor resection for the recurrent tumor.
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PMID:Case report: recurrence of soft tissue MFH in bone due to minute intravenous tumor emboli detected by MRI. 1453 25

Osteosarcoma (OS) is the most common primary malignant tumor of bone in children and adolescents. In spite of successful control of the primary tumor, death from lung metastasis occurs in more than a third of patients. To investigate the efficacy of zoledronic acid (ZOL) on the development, progression and metastatic spread of OS, we used a rat model of OS, with features of the disease similar to human patients, including spontaneous metastasis to lungs. Rat OS cells were inoculated into the tibial marrow cavity of syngeneic rats. OS development was associated with osteolysis mixed with new bone formation, adjacent to the periosteum and extended into the surrounding soft tissue. Metastatic foci in the lungs formed 3-4 weeks postcancer cell transplantation. Treatment with a clinically relevant dose of ZOL was initiated 1 week after tumors were established and continued once weekly or as a single dose. ZOL preserved the integrity of both trabecular and cortical bone and reduced tumor-induced bone formation. However, the overall tumor burden at the primary site was not reduced because of the persistent growth of cancer cells in the extramedullary space, which was not affected by ZOL treatment. ZOL treatment failed to prevent the metastatic spread of OS to the lungs. These findings suggest that ZOL as a single agent protects against OS-induced bone destruction but lacks efficacy against pulmonary metastases in this rat model. ZOL may have potential value as an adjuvant therapy in patients with established OS.
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PMID:Zoledronic acid protects against osteosarcoma-induced bone destruction but lacks efficacy against pulmonary metastases in a syngeneic rat model. 1992 13

Osteosarcoma is one of the most common primary bone tumors in childhood and adolescence. Metastases occurrence at diagnosis or during disease evolution is the main therapeutic challenge. New drug evaluation to improve patient survival requires the development of various preclinical models mimicking at best the complexity of the disease and its metastatic potential. We describe here the development and characteristics of two orthotopic bioluminescent (Luc/mKate2) cell-derived xenograft (CDX) models, Saos-2-B-Luc/mKate2-CDX and HOS-Luc/mKate2-CDX, in different immune (nude and NSG mouse strains) and bone (intratibial and paratibial with periosteum activation) contexts. IVIS SpectrumCT system allowed both longitudinal computed tomography (CT) and bioluminescence real-time follow-up of primary tumor growth and metastatic spread, which was confirmed by histology. The murine immune context influenced tumor engraftment, primary tumor growth, and metastatic spread to lungs, bone, and spleen (an unusual localization in humans). Engraftment in NSG mice was found superior to that found in nude mice and intratibial bone environment more favorable to engraftment compared to paratibial injection. The genetic background of the two CDX models also led to distinct primary tumor behavior observed on CT scan. Saos-2-B-Luc/mKate2-CDX showed osteocondensed, HOS-Luc/mKate2-CDX osteolytic morphology. Bioluminescence defined a faster growth of the primary tumor and metastases in Saos-2-B-Luc/mKate2-CDX than in HOS-Luc/mKate2-CDX. The early detection of primary tumor growth and metastatic spread by bioluminescence allows an improved exploration of osteosarcoma disease at tumor progression, and metastatic spread, as well as the evaluations of anticancer treatments. Our orthotopic models with metastatic spread bring complementary information to other types of existing osteosarcoma models.
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PMID:Establishment and characterization of in vivo orthotopic bioluminescent xenograft models from human osteosarcoma cell lines in Swiss nude and NSG mice. 2947 24

Metastatic spine disease is a heterogeneous clinical condition commonly requiring surgical intervention. Despite this heterogeneity, all cases share the common theme of altered tumor metabolism, characterized by aerobic glycolysis and high lactate production. Here we review the existing literature on lactate metabolism as it pertains to tumor progression, metastasis, and the formation of painful bone lesions. We included articles from the English literature addressing the role of lactate metabolism in the following: (I) primary tumor aggressiveness, (II) local tissue invasion, (III) metastasis formation, and (IV) generation of oncologic pain. We also report current investigations into restoring normal lactate metabolism as a means of impeding tumor growth and the formation of bony metastases. Both in vivo and in vitro experiments suggest that high lactate levels may be necessary for tumor cell growth, as small molecules inhibitors of lactate dehydrogenase (LDH5/LDHA) decrease both the rate of tumor growth and formation of metastases. Additionally, in vitro evidence strongly implicates lactate in tumor cell migration by driving the amoeboid movements of these cells. Acidification of the local bony tissue by excess lactate production activates CGRP+ neurons in the bone marrow and periosteum to generate oncologic bone pain. High lactate may also increase expression of acid sensing receptors in these neurons to generate the neuropathic pain seen in some patients with metastatic disease. Lastly, investigation into lactate-directed therapeutics is still early in development. Initial preclinical trials looking at LDH5/LDHA inhibitors as well as inhibitors of lactate transporters (MCT1) have demonstrated promise, but clinical work has been restricted to a single phase I trial. Lactate appears to play a crucial role in the pathogenesis of metastatic spine disease. Efforts are ongoing to identify small molecules inhibitors of targets in the lactogenic pathway capable of preventing the formation of osseous metastatic disease.
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PMID:Lactate and cancer: spinal metastases and potential therapeutic targets (part 2). 3129 86