Minimally Invasive Surgery for Spinal Metastasis: A Review

A new era in the management of spinal metastasis

Despite the recent advances in cancer treatment, the incidence of patients with spinal metastases continues to grow along with the total number of cancer patients. Spinal metastases can significantly impair activities of daily living (ADL) and quality of life (QOL), compared with other types of bone metastases, as they are characterized with severe pain and paralysis caused by skeletal-related events. Reduced ADL can also lead to treatment limitations as certain anticancer agents and radiation therapy are not compatible treatments; thus, leading to a shorter life expectancy. Consequently, maintaining ADLs in patients with spinal metastases is paramount, and spine surgeons have an integral role to play in this regard. However, neurosurgeon, orthopedic and spinal surgeons in Japan do not have a proactive treatment approach to spinal metastases, which may prevent them from providing appropriate treatment when needed (clinical inertia). To overcome such endemic inertia, it is essential for 1) spine surgeons to understand and be more actively involved with patients with musculoskeletal disorders (cancer locomo) and cancer patients; 2) the adoption of a multidisciplinary approach (coordination and meetings not only with the attending oncologist but also with spine surgeons, radiologists, rehabilitation specialists, and other professionals) to preemptive treatment such as medication, radiotherapy, and surgical treatment; and 3) the integration of the latest findings associated with minimally invasive spinal treatments that have expanded the indications for treatment of spinal metastases and improved treatment outcomes. This heralds a new era in the management of spinal metastases.

Pros and Cons of Minimally Invasive Spine Surgery

This paper reviews current knowledge on minimally invasive spine surgery (MISS). Although it has significant advantages, such as less postoperative pain, short hospital stay, quick return to work, better cosmetics, and less infection rate, there are also disadvantages. The long learning curve, the need for special instruments and types of equipment, high costs, lack of tactile sensation and biplanar imaging, some complications that are hard to treat, and more radiation to the surgeon and surgical team are the disadvantages.Most studies remark that the outcomes of MISS are similar to traditional surgery. Although patients demand it more than surgeons, we predict the broad applications of MISS will replace most of our classical surgical approaches.

Risk factors for pulmonary cement embolism after percutaneous vertebroplasty and radiofrequency ablation for spinal metastases

Objective

Pulmonary cement embolism is a rare but underestimated complication of vertebroplasty due to the relative lack of study and examination. This study aims to investigate the incidence of pulmonary cement embolism in patients with spinal metastasis who undergo PVP with RFA and to analyze the relative risk factors.

Methods

A total of 47 patients were retrospectively included and classified into pulmonary cement embolism (PCE) group and non-pulmonary cement embolism (NPCE) group by comparing pre- and postoperative pulmonary CT scan images. The demographic and clinical information of the patients was obtained. Demographic data in the two groups were compared using the chi-square test for qualitative data and the unpaired t test for quantitative data. Multiple logistic regression analysis was used to identify risk factors related to pulmonary cement embolism.

Results

Pulmonary cement embolism was detected in 11 patients (23.4%), and all patients were asymptomatic and followed up regularly. Risk analysis showed that multiple segments (≥3, p=0.022), thoracic vertebrae (p=0.0008), and unipedicular puncture approach (p=0.0059) were risk factors for pulmonary cement embolism. There was a high incidence of pulmonary cement embolism if bone cement leaked into the para vertebral venous plexus in the thoracic vertebra (p<0.0001). Vein leakage of cement was related to the integrity of the vertebral cortex.

Conclusion

The number of involved vertebrae, lesion location, and puncture approach are independent risk factors for pulmonary cement embolism. There was a high incidence of pulmonary cement embolism if bone cement leaked into the para vertebral venous plexus in the thoracic vertebra. Surgeons should consider these factors when formulating therapeutic strategies.

Quality of Life and Mental Health Status Among Cancer Patients With Metastatic Spinal Disease

This study aimed to investigate the quality of life and mental health status and further to identify relevant risk factors among advanced cancer patients with spine metastases. This study prospectively included and analyzed 103 advanced cancer patients with spine metastases. Patient's basic information, lifestyles, comorbidities, tumor characteristics, therapeutic strategies, economic conditions, quality of life, anxiety, and depression were collected. Patient's quality of life was assessed using the Functional Assessment of Cancer Therapy-General Scale (FACT-G), and anxiety and depression were evaluated using the Hospital Anxiety and Depression Scale (HADS). Subgroup analysis was performed based on different age groups, and a multivariate analysis was performed to test the ability of 20 potential risk factors to predict quality of life, anxiety, and depression. The mean total FACT-G score was only 61.38 ± 21.26. Of all included patients, 52.43% had skeptical or identified anxiety and 53.40% suffered from skeptical or identified depression. Patients had an age of 60 or more and <70 years had the lowest FACT-G score (54.91 ± 19.22), highest HADS anxiety score (10.25 ± 4.22), and highest HADS depression score (10.13 ± 4.94). After adjusting all other potential risk factors, age was still significantly associated with quality of life (OR = 0.57, 95%CI: 0.38–0.86, p < 0.01) and depression (OR = 1.55, 95%CI: 1.00–2.42, p = 0.05) and almost significantly associated with anxiety (OR = 1.52, 95%CI: 0.94–2.43, p = 0.08). Besides, preference to eating vegetables, time since knowing cancer diagnosis, surgical treatment at primary cancer, hormone endocrine therapy, and economic burden due to cancer treatments were found to be significantly associated with the quality of life. A number of comorbidities and economic burden due to cancer treatments were significantly associated with anxiety. Advanced cancer patients with spine metastases suffer from poor quality of life and severe anxiety and depression, especially among patients with an age of 60 or more and <70 years. Early mental health care and effective measures should be conducted to advanced cancer patients with spine metastases, and more attention should be paid to take care of patients with an age of 60 or more and <70 years in terms of their quality of life and mental health status.