Metastatic bone tumor

Introduction to metastatic bone tumor Tumors originating in other parts of the body, mainly malignant tumors, are transferred to bones by various means and continue to grow in the bone to form sub-tumors. A metastatic malignant tumor is a tumor formed by a malignant tumor originating from an extra-bone organ or tissue, transferred to the bone via the blood circulation or lymphatic system, and continues to grow. basic knowledge The proportion of patients: secondary to other cancerous diseases, the incidence rate is about 0.003% - 0.005% Susceptible people: no specific population Mode of infection: non-infectious Complications: osteosarcoma lymphoma muscle atrophy fracture

Metastatic bone tumor etiology

(1) Causes of the disease

Metastatic bone tumors are produced mainly through two channels, lymphatic or blood. Malignant tumors of any organ throughout the body can be transferred to the bone through the blood circulation or lymphatic system.

(two) pathogenesis

The main route of extramedullary malignant tumor metastasis to the bone is the blood circulation system. A few lymphatic systems, such as breast cancer, can infiltrate into the proximal humerus along the axillary lymphatic vessels. The primary tumor metastasizes to the bone, mainly through the blood circulation system. Less lymphatic metastasis.

Transfer process

In general, the transfer process can be divided into five phases:

(1) Tumor cells are detached from the primary tumor.

(2) Infiltration of peripheral capillaries by tumor cells.

(3) Tumor cells enter the blood circulation, and the formation and retention of tumor cell emboli.

(4) Tumor cells penetrate the blood vessels.

(5) The growth of tumor cells on the retained bone and the formation of metastases.

The near-heart end of the limb bones is rich in blood supply, the blood flow rate is slow, the tumor cells are easy to stay and grow here, forming metastases, and the trunk system is prone to metastasis, which may be related to the anatomical features of the vertebral venous system. The system is located in the hard There are no venous flaps around the meninges and vertebrae, and they communicate with the superior and inferior vena cava. When the pressure in the thoracic and abdominal cavity increases, the blood can flow backwards, increasing the chance of tumor cells staying there and forming metastases.

2. Classification

There are several other situations:

(1) vertebral vein type: because the vertebral venous system has extensive communication with the skull, chest, abdomen, pelvic and limb veins, there is no venous valve in the venous venous network, blood flow is slow, and it can also be stagnant or even countercurrent. By means of exercise extrusion, the effect of gravity and any factors that increase the pressure of the chest and abdominal cavity (such as coughing, sneezing, etc.), the vertebral venous system (Batson's vertebral venous system) can be directly transplanted to the spine without the lungs and liver. Thoracic, pelvic and other parts.

(2) pulmonary vein type: lung tumor embolus enters the pulmonary vein, through the heart, systemic circulation to bones and other tissues and organs, so lungs, bones and other organs can occur at the same time.

(3) portal vein type: the tumor embolus of the gastrointestinal tract enters the liver through the portal vein (the first filtration station), and then enters the heart from the inferior vena cava, the lungs, the body circulation to the bone and other parts, and the bone metastasis through the system is very less.

(4) vena cava type: the tumor embolus is returned to the heart via the vena cava, and then through the pulmonary artery to the lung (first filtration station), and then through the pulmonary veins, the heart, and the body circulation to the target organ.

(5) Selective metastasis type: tumor emboli is often affected by microvascular selection and the location of the primary tumor cavity.

3. Pathogenesis

Tumor metastasis is a complex, multi-step continuous process involving both tumor and host factors. From malignant tumor cells, the primary tumor is detached, invaded, destroyed, penetrates adjacent tissues, enters the circulatory system, penetrates the basement membrane, and infiltrates. Peripheral tissue, and the formation of metastases in the target organs, the question is how the tumor cells reach the target organs and form metastases, Page (1889) proposed the "seed and soil" hypothesis; Ewing (1928) proposed the anatomical positioning hypothesis, and this The hypothesis can only explain the metastasis of some tumors, but it cannot explain all. Although its specific details and mechanisms are not yet clear, recent studies have shown that carcinogenesis and metastasis are based on genetic material and are regulated by genes, resulting in changes in normal expression.

In the bone metastasis of tumors, the venous system, especially the vertebral venous system plays a major role. The most prone to tumor metastasis in children is neuroblastoma, lung cancer, thyroid cancer, breast cancer, metastatic bone tumors occur in The trunk bone, followed by the proximal end of the femur and tibia, occurs at the distal end of the femur and tibia. The site of metastatic bone tumors is also associated with the site of primary tumor growth. For example, bone metastases in breast cancer usually occur in the thoracic spine. Proximal humerus, thyroid cancer is common in the cervical spine and skull, of course, sometimes the occurrence of metastatic tumors is not related to the location of the primary tumor, metastases are mostly in malignant tumors, primary osteosarcoma, lymphoma, myeloma, Bone metastasis occurs and the joint is invaded. The pathogenesis is still not clear.

Metastatic bone tumor prevention

Recent studies have shown that metastasis is an active process that begins in the early stages of primary tumor growth. When the primary tumor begins to grow, metastatic potential tumor cells may have metastasized, but there is no clinical manifestation or early detection. The means of examination, therefore, preventive treatment should begin in the early stages of the disease, especially those who are close to the bones, should try to cut off the transfer link. It has been found that the combination of cortisone and heparin can inhibit the formation of tumor blood vessels. The primary tumor shrinks, the tumor metastasis rate decreases, propylimine 75 ~ 200mg is divided into 3 times, 5 to 14 days is a course of treatment, which has an inhibitory effect on colon cancer metastasis; Nm-23 gene product is in the inhibition metastasis phenotype makes an important impact.

Population prevention

Bone metastatic tumors are more common in clinical practice, and bone metastases can occur in any tumor. Therefore, those who have a history of malignant tumors should be more vigilant. If there is no obvious cause of the trunk and proximal limb pain, it should be highly suspected. Patients should go to the hospital as soon as possible to confirm the diagnosis. If the diagnosis is not clear, they should be reviewed regularly. At the same time, the primary disease should be actively treated. Different primary tumor patients may have different predilection sites and different types of metastases. Therefore, different groups should pay attention to the characteristics of different primary tumors, so that it is possible to detect early, early treatment of metastases, and of course, active and effective treatment of primary tumors is the fundamental to prevent their metastasis.

2. Individual prevention

(1) Primary prevention:

First of all, the focus should be on preventing the occurrence of primary tumors. Different tumors have different predisposing factors. For example, smoking can induce lung cancer, etc., and these factors should be avoided as much as possible. Secondly, when a malignant tumor occurs, it should be done as much as possible. Early detection, early treatment, strive to cure the primary tumor, avoid the source of bone metastasis cells, and third, for patients with a history of primary tumors, should be alert to the bone metastasis signal, regular review, and strive to find early metastases Effective treatment.

(2) Secondary prevention:

In general, bone metastases are the late manifestations of cancer, and the cure is currently rare. Therefore, the purpose of treatment of bone metastases is to prolong life, relieve pain, preserve function, and improve the quality of life of patients.

1 support and symptomatic treatment: can prolong life and relieve pain.

2 radiotherapy: for single or multiple of the main symptoms of metastatic tumors may be feasible radiotherapy, may reduce pain, relieve symptoms, the general dose of general radiotherapy is about 50Gy (5000rad).

3 hormone therapy: according to the sensitivity of the primary tumor to hormone therapy, choose different hormones for treatment, such as breast cancer metastasis testosterone, prostate cancer transfer estrogen.

4 chemotherapy: a lot of programs, according to the primary cancer causing bone metastasis to choose an effective program for chemotherapy.

5 surgical treatment: can be divided into two surgical methods, one is palliative surgery, whether it is a single metastasis, or a certain lesion of multiple metastases, resulting in strong pain and other major painful symptoms, in other ways invalid Surgical treatment is feasible, and the second is radical surgery. All the following conditions must be met: A. The primary lesion has not been found or has been completely removed; B. Single bone metastase; C. Good general condition; D. Bone metastasis It is not difficult to repair the tumor after it has been completely removed.

6 treatment of spinal metastases combined with paraplegia: for such patients should take active treatment measures, such as surgical decompression, if possible, such as surgical decompression, such as complete paraplegia, even if the surgery is completely decompressed, the possibility of recovery Sex is not big.

7 bone metastases with pathological fractures: this part of the patients can be internal fixation or amputation to relieve pain, for spinal metastases with pathological fractures, no paraplegia symptoms can be treated without radiotherapy, while resting in bed.

(3) Level 3 prevention:

Patients with metastatic malignant tumors are advanced and can be given support and symptomatic treatment. For bedridden patients, attention should be paid to the prevention of pneumonia, hemorrhoids, etc. In short, the prognosis of these patients is extremely poor.

Metastatic bone tumor complications Complications osteosarcoma lymphoma muscle atrophy fracture

Metastatic tumors can be complicated by primary osteosarcoma, lymphoma, myeloma, joint function disorders, muscle weakness or atrophy, pathological fractures, etc. Spinal metastases can cause paraplegia or radiculopathy pain and sensation in the spinal cord or nerve roots. obstacle.

Metastatic bone tumor symptoms Common symptoms Loss of bone pain, bone mass, loss of appetite, low heat and fatigue

About half of the patients have a history of primary malignant tumors, depending on the primary tumor. Most of them are bone metastasis during treatment or months or even years after treatment. Different symptoms and signs appear depending on the site of metastasis. The other part of the patient has no symptoms and signs of the primary tumor, and there is no history of this. The first symptom is the metastatic symptoms. Most of these bone metastases are from the kidney, thyroid and liver. Different tumors have their common metastatic sites and X-ray findings, the signs and symptoms of metastatic tumors are similar to those of malignant tumors. The tumors that metastasize to the limbs are mainly found in local lumps, while the metastatic bone tumors in the trunk are often the first manifestations of pain.

1. The location of the disease

According to Liu Zijun and other statistics of metastatic tumors in China, the most common metastatic sites are arranged in descending order: pelvis, femur, spine, ribs, humerus, scapula, humerus, jaw, sternum, clavicle and skull. In Japan, Sugiura (1986) The 6599 cases of bone metastases in the order of single-shot patients were spine, pelvis, femur, humerus, ribs, scapula, humerus, clavicle and sternum. The general rule is that the torso and limbs are high-end, limbs. The distal end of the heart is low-risk, and the extremities are rare. In the early stage, it is mostly single, and it can be multiple. It occurs in the metastatic tumor of the spine. The lumbar vertebra is the most, the thoracic vertebra is the second, the cervical vertebra is the least, breast cancer, lung cancer and kidney cancer. More metastasis to the thoracic vertebrae; prostate cancer, cervical cancer, rectal cancer mostly metastasized to the lumbar spine; while nasopharyngeal carcinoma, thyroid cancer tends to metastasize to the cervical spine, in addition, lung cancer, liver cancer, breast cancer is also easy to transfer to the upper end of the pelvis and femur, in In such cases, the primary lesion can be found after further examination, but 10% to 30% still have no primary lesion.

2. Symptoms and signs

The most common symptoms and signs of metastases include systemic symptoms, local pain in metastases, compression symptoms, pathological fractures, etc. Among them, local pain and pathological fractures are more common. About 40% of patients have original The history and signs of malignant tumors appear metastatic symptoms during or after treatment for several months or years. Most patients have no history and signs of primary tumors. The first symptom is metastatic symptoms, which causes diagnostic difficulties, such as liver cancer. , thyroid cancer, adrenal tumors and kidney cancer often have no primary symptoms.

(1) Pain: It is the most common symptom, accounting for about 70%. The time of pain can be early or late, the nature of pain can be light and heavy, the course of disease is generally longer, and the degree of pain is different. In the early stage, the pain is more Light, intermittent, gradually becoming persistent, severe cases are easy to attract attention, light is often neglected, located in the spine can be expressed as the waist, chest and back, rib chest, neck pain, often accompanied by unilateral or double in the thoracic spine Lateral intercostal neuralgia, sometimes in the lumbar vertebrae can show abdominal pain, the characteristics of pain are often changed, the brakes are more effective, the degree of pain is getting heavier and heavier, and the pelvis is often accompanied by the hip joint. Medial pain inside the femur; the upper end of the femur and the upper end of the tibia are often accompanied by joint dysfunction.

(2) swelling, mass: bone metastasis in the deep part of the tumor is often difficult to find the mass in the early stage, only reflects the local pain, some cases of superficial cases can be seen swelling and mass, accounting for about 5%, so because of the mass It is rare to see that tumors near the joint can cause joint function disorders. Tumor enlargement can have more or less compression symptoms near the important nerves, resulting in numbness, muscle weakness or atrophy. The diagnosis of many cases is Skeletal lesions are only discovered when pathological fractures occur, and special attention should be paid.

(3) compression symptoms: spinal metastases often appear in the spinal cord, cauda equina or nerve root compression symptoms, root nerve pain, feeling can be reduced, weakened muscles and even paralysis, often accompanied by sphincter dysfunction, with paralysis as the first cause Accounted for 2%, due to sputum and hospital admissions accounted for almost 50%, in the pelvis can cause rectal, bladder compression symptoms, dysfunction of the bowel movements, located in the limbs can also cause compression of blood vessels and nerve trunk.

(4) pathological fracture: often one of the primary symptoms, there is slight trauma or no incentive at all, that is, fracture occurs, the highest rate of occurrence in the lower limbs, once the pathological fracture occurs, the pain is aggravated, the swelling is obvious, in the spine is very Its coming soon.

(5) systemic symptoms: those with primary cancer, poor overall condition, often have anemia, weight loss, low fever, fatigue, loss of appetite, etc., no primary cancer, the patient's general condition is often good, some patients such as normal people The same, but soon around the symptoms.

Examination of metastatic bone tumors

Laboratory examination is an indispensable examination of bone metastases, and it is often used as a useful indicator for the progress of the disease, treatment effect and prognosis.

1. routine inspection

In addition to general routine tests, such patients may have decreased hemoglobin, decreased red blood cells, increased white blood cells, increased erythrocyte sedimentation rate, decreased plasma protein, and inverted A/G ratio. Alkaline phosphatase (ALP), acidity should also be performed. Phosphatase (ACP), lactate dehydrogenase (LDH), blood calcium, blood phosphorus, etc., about 1/10 of patients with breast cancer, lung cancer, liver cancer and kidney cancer, bone metastasis, elevated blood calcium, prostate Acid phosphatase is increased in cancerous bone metastasis, and alkaline phosphatase is elevated in osteoblastic metastases.

2. Bone marrow examination

When there is bone metastasis, bone marrow smears can find tumor cells.

3. Urine check

In the urine, catecholamines are increased, and the metabolites of catecholamines, 3-methoxy-4-hydroxy-mandelic acid (VMA), and homoglycolic acid (HVA) are also increased.

4. Pathological examination

In the case of suspected bone metastases, biopsy should be performed. The purpose is to clarify the diagnosis, design a treatment plan, and select an effective treatment method. Clinically, needle aspiration, drilling and incision of biopsy are often used, and the lesion is exfoliated. The smear is diagnosed by exfoliated cells.

Bone metastases are closely related to the primary tumors. Most of them are grayish white or dark red, which may have hemorrhage or necrosis. The osteolytic type is fragile, and the operation is easy to cut. The osteogenic cortical bone is hard and generally has no obvious boundary. Can penetrate the cortical bone into the soft tissue.

Microscopically, there are many adenocarcinomas with bone metastases, and there are few squamous cell carcinomas. Cancer cells sometimes differentiate well and sometimes have poor differentiation. If there is no evidence of primary cancer, it is difficult to judge the source according to metastatic tumor cells alone. Only a few differentiation is better. Metastatic cancer can identify its tissue sources, such as thyroid cancer, hepatocellular carcinoma, clear cell carcinoma of the kidney, and neuroblastoma. In osteolytic bone metastasis tumors, massive bone destruction, trabecular bone disappearance or reduction, in osteogenic bone metastasis tumors, bone destruction is small, and new bone formation.

Biopsy is the most direct method for definitive diagnosis of bone tumors. It should be performed as soon as possible. Single lesions should be directly excavated from the lesions. Multiple lesions should be considered from relatively easy to obtain lesions. At the beginning, many single bone tumor lesions should be combined with surgical removal of tumor tissue as much as possible. Sometimes, the tumor site is very deep or the surrounding structure is very compact, such as metastatic tumor of the spine vertebral body. It is also necessary to fully consider the risks of the biopsy operation itself and the complications after the operation. It is also a good diagnostic method to adopt other tissue examination methods such as needle biopsy.

5. Tumor marker detection

In recent years, tumor marker detection, tumor radioimmunoimaging and the use of polymerase chain reaction (PCR) in bone metastases have increased, which is also helpful for the diagnosis of primary cancer and tumor micrometastasis. There are: alpha fetoprotein (AFP) is useful for the diagnosis of primary liver cancer and bone metastasis, carcinoembryonic antigen (CEA) for the diagnosis of colon cancer, small cell lung cancer, breast cancer, pancreatic cancer, medullary thyroid carcinoma and its metastasis, CA19- 9 As a marker for pancreatic cancer, the positive rate of pancreatic cancer combined with CEA can be >90%; CA125 is a related antigen of ovarian cancer; prostate specific antigen (PSA) is used to diagnose prostate cancer and identify metastatic adenocarcinoma Nature; CA72-4 combined with CEA and CA19-9 for the detection of gastric cancer and bone metastasis.

Film degree exam

X-ray inspection

Including X-ray film, magnifying X-ray photography and tomography, X-ray examination is still an important examination method for the diagnosis of bone metastases, which can be used by most medical units. The X-ray findings of metastatic bone tumors are mostly tumors. The bones that occur have various destructive changes in the bones. The lesions are mostly confined within the bones, and the edges are unclear, sometimes difficult to distinguish from primary bone tumors.

(1) X-ray examination features: metastatic bone tumors can be single or multiple, single-shot occurs in a certain bone metastasis, limited to one place to produce bone destruction, so that the adjacent cortical bone expands and expands, X-ray It can be the same bone destruction, or form a cystic cavity of different sizes, or it can be extensive bone destruction. Multiple metastasis occurs in most bones, and can also be expressed in two forms, one is extensive The ground is scattered in most bones, one is continuous invasion of several adjacent bones, such as the ipsilateral humerus and proximal femur, the scapula and the proximal humerus, the metastatic tumor of the pelvis often involves the humerus and pubic bone. With the ischial bone, the metastatic tumor of the spine sometimes invades several adjacent vertebral bodies and ribs at the same time.

1 can use positive, side, oblique and other different angles and fault methods to understand the lesions, including the extent and volume of bone and soft tissue lesions;

2 to understand the type of bone destruction, bone metastases X-rays are mostly osteolytic, less osteogenic and mixed;

3 widely used, most medical institutions can implement;

4 The disadvantage is that it has radioactive damage to the human body, and the bone destruction stove is small and difficult to detect. When it exceeds 50%, it can be displayed, which reduces the sensitivity of detection.

(2) X-ray performance classification: X-ray findings of metastatic bone tumors are generally classified into osteolytic, osteogenic and mixed bone destruction:

1 osteolytic metastases: the most common osteolytic, accounting for more than 80%, kidney cancer, thyroid cancer, lung cancer, colon cancer, neuroblastoma and other bone metastases, often osteolytic destruction, its typical X-ray The performance is cortex, the medullary cavity has irregular bone dissolution and no reactive new bone formation, often multiple perforation, worm-like bone destruction, scattered in many bones, irregular edges, generally no hardened edges A small number can cause bone cortical swelling and periosteal reaction, and some single metastatic tumors have a large range, and bone destruction is also extensive, and pathological fractures often occur.

2 skeletal metastatic bone tumors: prostate pain, lung cancer, gastric cancer and nearly half of breast cancer bone metastases often show osteogenesis, X-ray films show that the bone is dense and irregular, rarely bone swelling and periosteal reaction, often spotted And the density of the block is increased, even in the form of ivory, during which the trabecular bone is disordered, thickened, rough, and sometimes there are a large number of new bone under the periosteum.

3 mixed metastatic bone tumors have both osteolytic and osteogenic changes.

X-ray features are diverse, which is related to the source of the primary tumor, the degree of differentiation and degree of destruction, extent, and time. In the early stage, only the sparseness of the bone marrow cavity is shown. This osteolytic destruction has no obvious expansion. There is no periosteal reaction. With the development, the bones inside and outside of the bone show irregular, reactive bone formation of the bone-dissolving image, which is worm-like, ice-like or "sweeping" bone-like destruction, prone to partial or complete Pathological fractures, there are also a small number of people with periosteal reaction and soft tissue mass imaging, prostate cancer, lung cancer, stomach cancer, and nearly half of breast cancer bone metastases are osteogenesis, the destruction area shows irregular dense shadow, the boundary is unclear In the meantime, the trabecular bones are disordered, thickened, rough, with little bone expansion and periosteal reaction, X-ray manifestations of mixed-type lytic and osteogenic bone destruction.

Bone metastases in neurofibromatosis often occur in the skull, femur, tibia, tibia and pelvis, and periosteal reactions are often seen.

Atypical bone metastases can have a high periosteal reaction like that of osteosarcoma and irregular new bone. Some of the slow-growing kidney and thyroid cancer bone metastases can show a clearer boundary, cortical phenotype, and expanded bone. Necrosis, similar to the giant cell tumor-like X-ray findings of the bone, imaging features.

(3) Metastatic bone tumors in different parts: plain films have different expressions.

1 pelvis: The lesion of pelvic metastases often occurs in the vicinity of the iliac crest and acetabulum. The osteolytic metastases begin to present with localized osteoporosis, which quickly develops into a worm-like, patchy, chiseled osteolytic Destruction and even large bone defects, the lesion boundary is not obvious, can involve the pubic bone, rarely periosteal reaction, occasionally soapy osteolytic destruction, osteogenesis type is spotted or cotton ball density increased shadow, osteogenic Metastatic lesions generally show changes in bone thickening at the bottom of the acetabulum, spreading to the pubic bone and tibia, showing a patchy shape, increasing the density of the lumps, and involving the appendix, with new bone formation at the edges.

2 Spinal column: Osteolytic metastatic lesions can often cause different degrees of destruction of the vertebral body. The vertebral body often changes in wedge shape or flat shape. The adjacent intervertebral space is generally intact. The attached metastatic lesions are also common. Osteogenic metastatic lesions make The vertebral body has a patchy or massive density or a dentin-like change.

Spinal metastases are difficult to detect in the early stage. Osteolytic metastases often show osteoporosis in one or several vertebral bodies in the early stage. They can be expressed as continuous or jumping vertebral bodies, or generally loose, often in combination with pathology. After the fracture is diagnosed, the vertebral body is compressed or flattened into a wedge shape, which may involve the attachment, the paravertebral is shadowed, the intervertebral space is normal, and the vertebral body of the osteogenic metastases has a patchy density increase image, and a few are ivory-like changes.

3 skull: osteolytic metastatic lesions often show multiple perforation or rat bite bone destruction, can also be localized flaky bone destruction, saddle pain in the skull base, saddle bottom and even skeletal bone destruction.

Most of the skull metastases are osteolytic, which can be expressed as single or scattered multiple well-defined osteolytic lesions or large unclear bone defects. The lesions often involve both internal and external plates and can invade the subcutaneous tissue.

4 ribs: mostly osteolytic, radiation-sensitive metastatic bone tumors after radiotherapy, often seen osteogenic hyperplasia repair.

5 bone metastases at the upper end of the femur and the upper end of the humerus: osteolytic bone destruction combined with pathological fractures are more common, the fracture can be in the femoral neck, intertrochanteric or trochanter.

2. Radionuclide scanning and gamma scintigraphy

The examination has great diagnostic value for metastasis, convenient and practical, early detection, accurate positioning, understanding the number of metastases, etc., and provides assistance for the choice of clinical treatment. Currently, this examination has been one of the commonly used examinations for bone metastases. It can be found that early metastatic cancer is about half a year earlier than X-ray findings, so it is an indispensable means for diagnosing metastatic cancer. Diagnosis of bone metastases is achieved by increased (concentrated) or less (sparse) radioactive intake. The presence of multiple concentrated lesions suggests that bone metastases are highly likely, and there are quite a few cases of metastatic lesions in single-concentrated concentrated lesions. The advantage is that the sensitivity is high, the detection rate of bone metastases can reach more than 90%, and is earlier than X. The lesion is found in the line about 3 to 6 months. The disadvantage is that the patient receives a large radiation dose and has poor specificity. For example, X-ray examination of the concentrated lesion can reduce the false positive rate and improve the diagnostic coincidence rate.

3.CT

It can help to determine whether there is tumor and accurate positioning, and its relationship with surrounding tissues. For the nature of the tumor should be combined with clinical judgment, CT examination of suspicious lesions with X-ray and whole body ECT examination of bone pain, if necessary, Iodine-containing contrast agent to increase the density of blood vessels and lesions, and increase the contrast between tissues, normal tissues and lesions, so-called "enhancement". The advantage of CT diagnosis is that it can well display the cross-sectional structure of lesions and The surrounding tissue relationship can clearly provide early mild bone structural damage and soft tissue block. For diagnosis, surgical plan formulation, prognosis evaluation, to find the primary lesion, CT guided positioning biopsy to help the spine Metastatic tumors can clearly show the compression of the dural sac and nerve roots caused by the invading intravertebral tumor tissue. CT enhanced scanning can further understand the blood supply of metastatic tumors.

4.MRI

MRI diagnosis of bone metastases is more sensitive than X-ray, CT, ECT. Its advantages are: 1 feasible three-dimensional imaging, accurate positioning; 2 wide range of examination, for the early detection and accurate diagnosis of limbs, pelvis, spinal metastases have unique advantages It can show the extent of invasion on the vertical axis, primary lesions and metastases in the medullary cavity, showing jumping metastases, etc.; 3 can directly display the affected vessels, no need to inject contrast agents; 4 normal tissue and metastases show The contrast is good; 5 shows that the bone marrow destruction is clear; 6 no radioactive damage.

Most bone metastases have a low or equal signal in the T1-weighted image, and the T2-weighted image is a high signal. However, due to the different phenotypes of the bone metastases, the MRI signal characteristics are different, and the performance of different parts is different, such as lung cancer osteogenesis. Transfer to the "target sign" on the pelvis, the "jump sign" of the spinal metastases, the "intervertebral disc embedding sign", the "intervertebral space enlargement sign", etc., for the paravertebral and epidural masses, the dural sac compressed spinal cord and Its secondary changes, the nerve roots can be clearly displayed.

Some authors have compared the diagnostic effects of X-ray, CT, MRI, ECT and infrared thermography on bone metastases. The experience of most authors is that ECT and infrared thermography are effective systemic examination methods for bone metastases, but false. High rate, poor positioning; ECT has radioactive damage to the human body and infrared thermal imaging technology does not cause any damage to the human body; X-ray sensitivity is low, when infrared and ECT are positive, X-ray examination can be further performed; CT and MRI can not be used for the above examination The confirmed patient is an alternative reliable method. MRI is the best imaging method for displaying bone marrow, and it can be three-dimensionally imaged. It shows that the early bone metastasis is the most sensitive and can accurately display the site and extent of invasion. It is the best imaging method for spinal metastases.

5.B-ultrasound

Since the sound wave of B-ultrasound is almost completely reflected on the surface of normal bone, it is attenuated in bone tissue and it is difficult to penetrate the tissue. Only in the case of pathology, sound waves can pass through the diseased bone. Therefore, B-ultrasound is more suitable for osteolytic type. The bone metastases with bone destruction are mainly characterized by a relatively uniform spotted echo or irregularly strong echogenic spot in the hypoechoic area of the tumor, a spot or a liquid echo dark area, accompanied by dense Light spot, its advantages can directly observe the size of the metastases and guide the biopsy.

6. Angiography

Angiography can show typical malignant changes, such as blood supply, capillary proliferation, but disordered, "vessel lake" phenomenon, etc., can also be intervened at the same time of angiography.

Diagnosis and differentiation of metastatic bone tumor

diagnosis

The diagnosis of metastatic bone tumors is relatively easy after the diagnosis of primary tumors, but some metastatic bone tumors with bone tumors as the first symptom often rely on various laboratory tests for diagnosis. The order of tumors, selective laboratory tests, can help to make a correct diagnosis, rely on clinical manifestations and auxiliary examinations, and pathological examinations can help diagnose.

1. Diagnostic points

(1) Anyone who diagnoses malignant tumors should be monitored for tumor micrometastasis 40 to 70 years old, especially those with a history of malignant tumors, where there is unexplained pain in the trunk or limbs near the extremities, swelling or mass should be Highly suspected whether there is any transfer, commonly used methods include ECT, infrared thermal imaging technology, immunoassay, radioimmunoassay and PCR detection, etc. It is best to start before surgery. If the tests are normal, they can be reserved for the original data. Review and comparison; if the test results are abnormal, bone metastasis should be suspected for further examination.

(2) X-ray examination of suspicious parts: the main diagnostic basis for diagnosis and differential diagnosis is to use the exclusion method, that is, to exclude the inflammatory disease of the bone and to exclude the primary tumor of the bone, the primary tumor of the bone in the limbs, the spine and The pelvic bone has its own good site and its own special changes; it does not meet the special changes of the primary tumor, and there are malignant bone tumors, that is, bone metastasis should be suspected. Radionuclide, CT and MRI should be examined as appropriate.

(3) Biopsy is feasible when necessary: Biopsy is an effective method for diagnosing tumors and judging the nature. Commonly used biopsy is performed.

(4) For patients without a history of malignant tumors: should be thoroughly and carefully examined to find the primary lesion.

2. Diagnosis

Primary osteosarcoma, lymphoma, myeloma, malignant tumor metastasis into or near the joint, invading the single joint, showing local pain, swelling and dysfunction; often bloody exudate in the joint cavity, joint The effusion will relapse quickly after puncture and drainage. Tumor cells can be found in the effusion of the joint cavity. Synovial biopsy can detect the invasion of tumor cells, which can be diagnosed.

Differential diagnosis

The identification of bone metastases and primary tumors, in the limbs and spine of the limbs, because the performance of the primary tumor is clearer, the identification is easier, in the pelvic tumors, the special performance is less, the identification is more difficult, the single lesion with the bone Identification of primary tumors, such as Ewing's tumor.

Biopsy is a reliable means of diagnosing tumors, and is also the main means of differential diagnosis. Puncture biopsy is often used for bone metastases.

Looking for the primary tumor: If the primary tumor can be found, the diagnosis of the bone metastasis is established. Even if the primary tumor is not found, the diagnosis of the metastatic tumor can be established as long as the primary tumor is excluded by biopsy.

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