The 2010 Chinese version of the Expert Consensus on Clinical Treatment of Bone Metastases and Bone Related Diseases of Malignant Tumors was published, which is of great significance in guiding clinicians to prevent and treat bone metastases.
Clinical data show that about 2.3% of lung cancer patients have bone metastasis as the first symptom, and about 30%-70% of lung cancer patients will have lung cancer bone metastasis during the course of their disease, and the longer the survival period, the higher the incidence of lung cancer bone metastasis. The occurrence of bone metastasis is caused by hematogenous dissemination. The high incidence sites are pelvis, ribs, vertebrae and proximal long bones. Niu Po, Department of Radiotherapy, Henan Provincial People’s Hospital
Pain is the most common symptom of lung cancer. Inflammation and thickening of the periosteum is the root cause of pain. Often bone metastases are present before the onset of bone pain. Bone metastases occur in 18.3% of patients with early stage non-small cell lung cancer, but only 27.2% have bone pain, and most patients have no pain symptoms. Forty percent of patients with small cell lung cancer have a positive bone image at diagnosis, while bone metastases are often diagnosed in the absence of symptoms.
Primary lung cancer bone metastases are usually osteolytic in nature. Pathological fractures occur when bone strength is compromised, and collapse and distension of the vertebral body can cause spinal cord compression. Both paraneoplastic syndrome without bone destruction and osteolytic bone metastases may cause hypercalcemia and lead to disease progression.
There are various methods to examine bone metastases, the most commonly used being radionuclide bone scan (ECT). Both computed tomography (CT) and magnetic resonance imaging (MRI) can be used for radiotherapy planning and for further differential diagnosis of skeletal abnormalities. the accuracy of PET and bone scan is 96% and 66%, respectively.
For bone metastases from malignant tumors, individualized comprehensive treatment is recommended to promote the clinical standardized diagnosis and treatment of bone metastases from malignant tumors with the goal of relieving symptoms and improving patients’ quality of life, using bisphosphonates, analgesic drugs, radiotherapy, bone surgery and symptomatic supportive treatment as the main means.
Compared with other metastases, patients with lung cancer bone metastases feel painful physically, but the risk is less than brain metastases and intrapulmonary metastases. There are many treatment options for lung cancer bone metastases, roughly ① external radiotherapy; ② bisphosphonates; ③ isotopes; ④ targeted drugs.
(1) External radiotherapy is a more traditional treatment, which has better pain relief and can effectively prevent paraplegia in patients with more serious cone bone metastases, but has no repair effect on broken bone.
(2) Bisphosphonates. Bisphosphonates have become an important supportive therapy by delaying bone destruction, reducing or delaying the occurrence of bone-related events, and improving patients’ quality of life. Among all bisphosphonates, only zoledronic acid has indications for bone metastasis in lung cancer, while other products do not have indications for lung cancer, which is the reason why zoledronic acid, a third-generation bisphosphonate, is more widely used. The third generation of zoledronic acid is not very different from the second generation of Bonin and Eben, but the dosing time is much shorter. The first dose of the second generation of bisphosphonates is usually slightly larger, and the dosing time is about 4-6 hours, while the third generation is usually within half an hour. Some transient side effects can occur with bisphosphonates, usually lasting 24 to 48 hours, and the side effects of imported drugs are less than those of domestic drugs. (b) Bisphosphonates also have pain-relieving effect, but it has the advantage of repairing bone cells.
(3) The more commonly used isotopes for bone metastasis of lung cancer are strontium 89 (sr89), samarium 153 and yunker, which are usually titrated once in 4-6 months.
(4) In addition, although there is no information on the efficacy of targeted drugs for bone metastases, according to the actual use of many patients and feedback from patients, the treatment effect for lung cancer bone metastases is also good in cases sensitive to ERSA.
The World Health Organization emphasizes four priorities for cancer prevention and treatment: ① prevention according to the cause; ② early detection, early diagnosis and early treatment; ③ concentration of various superior means for treatment; ④ palliative care. The management of bone metastases and bone-related events is another element of palliative care following the principle of three-step pain relief for cancer. It is hoped that the focus of health work will be shifted forward and that the concept of prevention will be adopted. It is hoped that all people will pay attention to health care and develop good lifestyle habits to prevent the occurrence of diseases. Therefore, the 2010 Chinese version of “Expert Consensus on Clinical Diagnosis and Treatment of Bone Metastases and Bone Related Diseases in Malignant Tumors” newly recommended the use of zoledronic acid once every six months to prevent bone loss and osteoporosis caused by chemotherapy, etc. in tumor patients, thus preventing bone related events such as pathological fracture, spinal cord compression, radiotherapy or bone surgery due to bone pain, and prolonging patients’ survival time.