How to conduct bone cancer examination

How to conduct bone cancer examination? There are many methods to examine bone tumors. Because bone tumors have a great impact on the human body, it is very important to understand the examination methods of bone tumors in medicine. Let us learn about it through the article below.

1. CT

CT is a cross-sectional scan of the lesion, which can clearly show the location, range and relationship of the tumor to muscles, organs, nerves and blood vessels. It can also clearly show the internal structure of the tumor. Some tiny lesions or early malignant bone tumors may appear normal on X-rays, and CT is very sensitive to tiny bone destruction, the range of lesion involvement and the density value inside the bone destruction. It can show the range of bone cortex and articular surface destruction earlier than plain films, clarify the extra-bone and intramedullary invasion, and detect soft tissue masses at an early stage.

CT enhanced scanning refers to the use of a high-pressure syringe to quickly inject contrast agent through the vein, and then quickly and continuously scan to observe the changes in blood supply of the lesion in the arterial and venous phases, increase the contrast between the lesion and the surrounding normal tissue, and facilitate the discovery of lesions and differential diagnosis. Enhanced scanning can also show the blood supply of the tumor, providing a basis for the formulation of treatment plans and preoperative embolization of the blood supply artery. CT enhanced scanning has become a routine examination for bone tumors.

2. X-ray film

X-ray films are the first choice and important means of examination in the diagnosis of bone tumors. According to the location of the lesion, the type of bone destruction, the integrity of the bone cortex, the edge of the lesion, the presence or absence of sclerotic borders, the presence or absence of residual bone in the lesion, tumor cartilage calcification, tumor bone formation, the presence or absence of periosteal reaction and its type, and changes in the soft tissue around the lesion area, it can indicate tumorous or non-tumorous, benign or malignant, primary and secondary lesions. With the development of digital technology, ordinary X-ray films have been replaced by CR and DR. With the improvement of the quality of X-ray films, we can obtain more and more accurate information, thereby making an accurate diagnosis. As the preferred examination method for bone tumors, we should pay attention to it and not ignore the most basic examinations because of the emergence of large-scale examinations such as CT and MRI.

PET-CT

The working principle of PET-CT is to put PET (positron emission tomography) and CT together. The data obtained is not only used to reconstruct CT images, but also to reconstruct PET images. The displayed image is the result of the fusion of the two images, that is, the metabolic imaging of the cells and their anatomical location.

PET-CT is a combination of functional imaging and anatomical imaging. Its role is first of all to diagnose diseases, especially tumors. After the tracer 18F-FDG is injected into the human body to replace deoxyglucose, the glucose metabolism in the target area is observed, and the nature of the tumor is diagnosed based on the high metabolic characteristics of malignant tumors. PET-CT is particularly advantageous for areas with complex anatomical parts and unclear density contrast. Its role is also reflected in the treatment of tumors, including the delineation of radiotherapy target areas, optimization of chemotherapy regimens, and guidance of surgical resection range. PET-CT is currently an advanced examination method with the characteristics of non-invasiveness. It can show the metabolic conditions of various parts of the body and will play a greater role in the diagnosis and treatment of bone and soft tissue tumors and bone metastases. Due to the existence of false positives and false negatives, its results must be comprehensively judged.

IV. MRI

MRI is what we usually call magnetic resonance imaging. MRI is more sensitive than X-rays and CT in detecting bone tumors, especially in observing the infiltration range of lesions, the relationship between soft tissue masses and blood vessels, the range of muscle edema, and the path of tumor expansion. However, it has poor display of bone cortex and calcification. Therefore, MRI is mainly used to show the relationship between tumors and surrounding tissues, clarify the size and invasion range of tumors, distinguish the tissue components of lesions, determine the range of tumor intramedullary infiltration, and determine the relationship between tumors and surrounding important blood vessels and nerves, which is very important for making preoperative plans. In addition, MRI is also used to observe and evaluate the efficacy of radiotherapy, chemotherapy and surgery for bone tumors, and to detect complications in the early stage and detect tumor recurrence and metastasis.

5. B-ultrasound

Under normal physiological conditions, ultrasound waves are almost completely reflected on the surface of bones and it is difficult to penetrate bone tissue, so it is difficult to obtain images of the deep surface of bones. However, under pathological conditions, ultrasound waves can partially penetrate bone tissue due to changes in the physical properties of bone tissue, making it possible to diagnose bone diseases including tumors. Ultrasound can more accurately estimate the location, range and size of tumors, and can indicate whether soft tissue tumors have destroyed the bone cortex. Ultrasound examination plays a very important role in the diagnosis of soft tissue tumors, especially for masses adjacent to joints. Ultrasound examination can be used to understand the size and depth of soft tissue masses, as well as whether the tumor is cystic or solid, and whether the tumor has rich blood supply, which helps to determine whether the soft tissue tumor is benign or malignant. Therefore, B-ultrasound is most widely used in the preoperative diagnosis and postoperative follow-up of soft tissue tumors.

6. Angiography

Digital subtraction angiography (DSA) is a new medical imaging diagnostic technology used in clinical practice in recent years. It is used to detect the vascular distribution of bone tumors, the main vascular structure of lesions, and to show abnormal changes in normal blood vessels and the status of abnormal blood vessels. The purpose of angiography is, on the one hand, to show the blood vessels supplying the tumor and the scope of tumor invasion. For example, sacrococcygeal tumors can be supplied by one internal iliac artery or by both internal iliac arteries. Some tumors can be supplied by lumbar arteries or median sacral arteries in addition to the internal iliac arteries. The type of blood supply can be determined through angiography. On the other hand, the nature and malignancy of the tumor can be accurately judged based on the performance of the tumor blood vessels and blood supply, thereby providing an objective basis for the formulation of treatment plans and preparation for surgical resection.

7. Whole body bone scan

Isotope bone scanning uses radionuclides to detect metabolic abnormalities in bone tissue, so it can show certain bone tissue lesions before abnormalities appear on X-rays and CT scans. In addition, bone scanning can assist other imaging examinations to clarify clinical diagnosis. Bone scanning has a high sensitivity, but its disadvantage is that it is not specific. It can accurately locate lesions, but it is difficult to diagnose them. There are certain difficulties in distinguishing between neoplastic and non-neoplastic diseases. Bone tumors, arthritis, bone infarction, osteomyelitis, orthopedic surgery, and fractures can all cause radioactive concentration. Isotope bone scanning is mainly used to screen for multiple bone lesions. It is only a screening and cannot be used as a qualitative diagnosis.