The reactivation and healing of inactivated bone after microwave treatment takes a long time, and the strength of bone is low before healing is achieved, thus risking pathological fracture. We recommend this technique for bone tumors in areas where prosthetic replacement is unsatisfactory and bone healing is relatively strong, such as the pelvis and spine, or for the treatment of aggressive benign bone tumors, such as giant cell tumor of bone. For malignant tumors around the hip and knee joint, we preferentially recommend osteotomy of the tumor segment and artificial prosthesis replacement surgery, but if the patient cannot accept artificial prosthesis replacement, or the bone invasion is relatively small, microwave in situ inactivation therapy can still be chosen.
Vertebral body tumor
Due to the special anatomical characteristics, the surgical treatment of malignant tumors of the spine is very difficult. In the past, due to the limitations of surgical techniques and instruments, only decompression and stabilization surgery could be performed for malignant tumors of the spine, while the tumor itself often could not be effectively resected. As a result, the tumor continues to grow after surgery, which is ultimately life-threatening, and the continued growth of the tumor can soon lead to new nerve compression or failure of internal fixation due to invasion of the tumor into the surrounding vertebral body. Therefore, in order to improve the treatment of spinal malignancies, in addition to decompression and internal fixation, complete resection of the tumor is necessary to avoid or reduce the chance of local recurrence, which is the concept of removing the tumor outside the safe margin in surgical oncology. However, for spinal tumors, this is almost impossible to achieve with conventional surgery. Although the concept of total en bloc spondylectomy has been proposed by some surgeons, it is very difficult to perform total spondylectomy, which often causes life-threatening or a series of complications due to long operation time and uncontrollable intraoperative bleeding.
How can we ensure complete removal of tumor cells while improving the safety of the surgery? Microwave in situ inactivation technology provides such a possibility. While performing traditional decompression and internal fixation surgery, microwave energy is introduced into the tumor center of the vertebral body using a specially designed microwave antenna to kill tumor cells through microwave heat generation, and by adjusting the direction and depth of the microwave antenna and the time of microwave inactivation, almost all corners of the entire vertebral body can be killed. By adjusting the direction and depth of the microwave antenna and the microwave inactivation time, the tumor cells can be killed in all directions in almost all corners of the vertebral body, thus achieving the purpose of “tumor removal”.
The main advantages of this technology are
1, through in situ microwave inactivation of tumor tissues, on the basis of the inoperative total vertebral body resection, the tumor tissues can be killed, thus achieving or approaching the effect of total spine resection, thus obtaining good local control and avoiding or reducing the possibility of postoperative recurrence.
2. microwave inactivation followed by lesion scraping can greatly reduce bleeding because the blood vessels in the tumor have been coagulated.
3. After scraping, the bone shell at the edge of the vertebral body is preserved, which is convenient for reconstruction and internal fixation, and the spine is highly stable after surgery, so that the patient can get out of bed at an early stage.
Pelvic tumor
The surgical treatment of pelvic malignant tumor has been difficult, and the results of the widely used expanded resection and artificial prosthesis replacement are not ideal. On the one hand, due to the rich blood supply, resection surgery often leads to massive bleeding and high surgical complication rate; on the other hand, the current pelvic prosthesis design is not ideal, and the intraoperative installation process is complicated, which greatly increases the surgical trauma and time, and the postoperative function is poor, while the complication rate of prosthesis loosening and infection is also high. Microwave in situ inactivation technique provides us with a more ideal option for.
(1) Intraoperative tumor exposure only, not resection, greatly reducing intraoperative bleeding.
(2) The autologous bone structure is preserved after inactivation, and no special reconstruction is required.
(3) The iliac bone is cancellous and the surrounding muscle is abundant, so the bone healing ability is relatively strong.
Giant cell tumor of bone
Although giant cell tumor of bone is a benign bone tumor, it is prone to recurrence after simple curettage because of its aggressive growth characteristics. In recent years, more and more hospitals adopt osteotomy and artificial prosthesis to treat giant cell tumor of the extremities, which can avoid recurrence after surgery, but at the expense of their own joints and expensive treatment costs, and the artificial prosthesis has a certain service life, and most patients still need another surgery to revise and replace the artificial joint.
We have successfully treated giant cell tumor of bone by in situ microwave inactivation. The basic idea is to thoroughly inactivate the tumor and its surrounding area with multiple inserted microwave electrodes, followed by scraping the inactivated tumor tissue, filling the tumor cavity with bone cement or bone grafting, and deciding whether to perform internal fixation with a plate depending on the degree of bone destruction. Since the tumor tissue is completely inactivated to avoid postoperative recurrence, and the tumor segment is not resected to preserve the own joint, there is no need for prosthesis replacement, thus saving treatment cost. Moreover, because of the small extent of inactivated bone, the bone healing time is relatively short, and the risk of pathological fracture is also smaller.
Minimally invasive treatment of bone metastasis cancer
With the advancement of comprehensive treatment, the survival period of patients with malignant tumors is gradually prolonged, and accordingly, the number of patients with bone metastatic cancer is increasing. For single bone metastases whose primary tumor is controlled, radical resection can be considered. However, for patients with uncontrolled primary tumor or multiple metastases, radical resection of metastatic lesions cannot benefit the patients, and the patients are often in poor health after a long period of tumor and various treatments, so palliative treatment can be considered for these patients to relieve local pain. Under the guidance of C-arm or CT, microwave antenna is placed percutaneously into the center of the metastatic lesion to perform tumor inactivation, which can achieve immediate pain relief and basically does not add additional damage.
Limb malignant tumor
For malignant tumors around the hip and knee, due to the relatively mature technology of artificial prosthesis and good postoperative function, we prefer to recommend osteotomy of the tumor segment and artificial prosthesis replacement. However, for patients who refuse to accept prosthesis replacement, microwave in situ inactivation technique can still be considered, as long as the affected limb is weight-bearing late after surgery and pathological fracture is avoided. Good function can still be obtained through non-weight-bearing functional exercises of the joint. Especially for some low-grade (relatively low malignancy) tumors, due to the long expected survival period, the complications associated with prosthesis replacement and possible revision can be avoided, and the postoperative bone healing time is relatively short due to the relatively small extent of tumor invasion and inactivation.