(A) Bone metastasis of prostate cancer The chance of bone metastasis of prostate cancer is the most, the incidence rate is 50%~80%. The incidence of bone metastasis of prostate cancer is 50.9%, of which 92.6% are osteogenic changes and 8.4% are simply osteolytic changes. The metastatic sites are most often in the pelvis, followed by the lumbar spine, thoracic spine, cervical spine, femoral ridge, rib cage and sternum, and the age is mostly above 60 years. Radiographic manifestations: osteogenic metastases appear as round or oval dense shadows on a bone background without changes in bone appearance, sometimes in the form of a map, with irregular margins. The density is increased in a cotton wool-like manner. Prostate cancer bone metastases are more typical, and the diagnosis is generally not difficult when combined with clinical findings. Laboratory tests: serum alkaline phosphatase is often increased, about 80%-85%; serum acid phosphatase is also significantly increased, which is important for the diagnosis of prostate cancer bone metastasis. (B) Bone metastasis of breast cancer Breast cancer is one of the tumors most prone to bone metastasis, and bone metastasis occurs more and earlier than lung cancer. The age of onset is young, averaging 45 years old, and bone metastases are reported to occur in 33%-73% of all breast cancer cases. More than half of the autopsies have bone metastases, so it is suggested that routine skeletal examination is important to observe the presence or absence of metastases before breast cancer surgery. X-ray manifestation: basically, osteolytic destruction is the main feature. The lesion starts in the medullary cavity and erodes and destroys the bone cortex from inside the bone outward, and the lesion is more extensive, often destroying all of the bone cortex, usually without periosteal reaction. When the primary tumor is a hard cancer, metastases tend to be osteogenic, and the lesions are more limited. Mixed metastases account for about 12%. (C) Bone metastasis of thyroid cancer Bone metastasis of thyroid cancer is second only to prostate cancer and breast cancer, accounting for about 50%. Since the malignancy of thyroid cancer varies greatly, the clinical and radiographic manifestations of thyroid cancer bone metastases are more special. The clinical manifestations are often not obvious, and often the first manifestation is metastasis: painless mass, mostly egg-sized, soft, no pressure pain, clear margins, normal skin color, vascular murmur on auscultation, and dark red bloody fluid can be extracted. Radiographic manifestation: Bone metastasis of thyroid cancer, mostly in the skull, ribs, spine, pelvis and proximal humerus and femur; osteolytic destruction is predominant, showing large slices or map-like bone defects. Sometimes there is a multi-capsular area of destruction with bony septa within the lesion, and this sign is considered to be the characteristic manifestation of thyroid cancer bone metastasis. The destruction of the skull is predominantly exostosis, and the residual bone crest is mostly perpendicular to the skull. In a few cases, there is periosteal reaction. (iv) Bone metastasis of lung cancer The incidence of bone metastasis of lung cancer has different opinions, Abrams reported an incidence of 32.5%, accounting for the fourth place. The incidence rate reported in domestic literature is 6.7% (1964) to 45.6% (1987), with an increasing trend year by year. Bone metastases from lung cancer are more frequent in women, and the age is mostly above 50 years. Radiographic manifestations: they are usually found in ribs, spine, pelvis and skull, followed by humerus and femur, and also metastasized to tibia, fibula, ulna, radius and foot bone; the foci of destruction are single or multiple, mostly osteolytic with blurred edges, and the bone cortex is often destroyed; sometimes the ribs, sit bones and long bones are involved, and the backbone can be completely destroyed and absorbed without leaving traces; osteogenic metastases of lung cancer are rare, and they appear as speckled or flocculent density. Osteogenic metastasis of lung cancer is rare, which is characterized by speckled or flocculent density, with density ranging from hairy glassy to ivory-like. In some cases, soft tissue masses appear, and generally there is no periosteal reaction. The metastasis of the peripheral type occurs in the short bones of hands and feet. 163 cases of hand bone metastasis were reported in the literature, 68 cases of primary tumor in the lung, accounting for 41.7%, showing osteolytic destruction of the terminal phalanges and phalanges, accompanied by spherical or lobulated soft tissue swelling. It is also seen in the tibia and ulnar radius. (E) Bone metastasis of bladder cancer is rare in China, and Abrams reported that the incidence is 26%, accounting for the 5th place. It is more common in men than women, and the age is around 60 years. It occurs in the pelvis, spine and proximal femur. The lesions are often solitary, with osteolytic destruction, variable lesion size, blurred margins, and destruction of the bone cortex, so pathological fractures often occur. Local soft tissue masses appear. (f) Bone metastasis of kidney cancer About 23.5% of the metastases occur, mostly in femur, humerus, spine, pelvis and ribs. It is often solitary, with osteolytic destruction and slight expansion of the bone stem, which can erode and destroy the bone cortex and cause pathological fracture. There are bony septa within the bone defect area, which resemble primary renal tumors. It may also be sclerotic, or have extensive multi-layered periosteal reaction. (VII) Bone metastasis of cervical cancer Metastasis of uterine tumors to bone is most common in cervical cancer and less in uterine body cancer at the age of about 53 years. Most of them metastasize to the spine, pelvis, skull, femur and humerus. The lesions are often multiple, with osteolytic changes and a small amount of osteogenic changes, and the bone cortex is mostly destroyed without periosteal reaction. (H) Bone metastasis of liver, stomach, esophagus and colon cancer has a lower incidence, more men than women, and the age is between 45 and 55 years old. Preferred sites are spine, pelvis and limb bones. Osteolytic changes, bone cortical destruction, pathological fracture, mostly without periosteal reaction. Sometimes there are local soft tissue masses. (ix) Bone metastasis of nasopharyngeal carcinoma Bone metastasis of nasopharyngeal carcinoma is not uncommon, with an incidence rate of 8.5% as reported in the domestic literature, more men than women, aged 30-60 years old, with an average of 50 years old. Bone metastases can occur before, during and after radiotherapy, and those metastases to bone often have mild or severe pain. X-ray manifestations: the spine and ribs are the most frequent, followed by the pelvis and proximal femur, often multiple, a few single; osteolytic, osteogenic and mixed types are all present. 66.6% of osteolytic type, 21.0% of osteogenic type and 12.8% of mixed type according to Jonathan. Osteolytic type: early worm-like or small piece of destruction, progressive expansion, irregular margins; late osteolytic changes in large pieces, or even the whole section of bone dissolution disappeared, with pathological fracture. Osteogenic type: Early on, there are more small lamellar hyperdensity shadows in the bone, or there is a gradual increase in density in the form of hairy glass, and osteogenesis occurs mostly in the bone without involving the bone cortex. Mixed type: both osteolytic and osteogenic changes are present, which can lead to bone expansion. Other manifestations: a few metastases have obvious periosteal reaction. All types of metastases may have large soft tissue masses. (X) Neuroblastoma bone metastasis Neuroblastoma is also known as adult neuroblastoma, sympathetic neuroblastoma, sympathetic neuroblastoma. Adrenal medullary tumors are mostly subclassed, and this disease is a more common malignant tumor in children, especially in young children. The incidence is 3.4%~18.1%, which can be divided into thoracic and abdominal types. 65.5% occur in the abdomen, with three major clinical manifestations: convex and concave upper abdomen, hard and fixed, often accompanied by abdominal painful masses; rapid deterioration of general condition; and early bone metastasis. Early bone metastasis is one of the important features of this disease. 1. The skull shows osteolytic and osteogenic manifestations, or mixed manifestations. Osteolytic changes are often located near the cranial suture, showing worm-like destruction or osteomalacia. The characteristic manifestations of cranial metastases are symmetrically distributed destruction along the cranial suture and radiating bone pins in the cranial plate. The cranial lesions are surrounded by soft tissue masses. The pelvis, scapula, mandible and other flat bone radiographs are basically the same as the cranial bone. 2. Spinal neuroblastoma also often invades the spine, especially the so-called dumbbell-shaped tumor can erode and destroy the vertebral body, which shows osteolytic changes of varying sizes, compressed and flattened, with uneven and blurred edges. Sometimes it also shows osteomalacia and depression of the anterior and posterior edges of the vertebral body. 3, long bones are more commonly invaded by the femur. The lesions are often located in the metaphysis of the long bones and show early osteophytes in the metaphysis, with gross, blurred and uneven trabeculae, and further development of sieve-like and speckled small translucent areas with mild surrounding osteophytes. The lesions are often symmetrically distributed, sometimes with symmetrical bone defects and laminar periosteal reactions. The extensive bone damage of neuroblastoma should be distinguished from leukemia, Ewing sarcoma and acute osteomyelitis. (XI) Bone metastases from other carcinomas Submandibular gland carcinoma, parotid gland carcinoma, retinoblastoma, melanoma, squamous epithelial skin carcinoma, laryngeal carcinoma, gingival carcinoma, buccal mucosa carcinoma, spermatocellular carcinoma and choroidal epithelial cell carcinoma have been reported to occur in China, but they are very rare.