(P 469) IMPACT OF A SPECIALIZED OUTPATIENT CLINIC ON BONE MRTASTASIS AND ITS BURDEN ON SPINE SURGEONS

Objective: Advances in drug therapies have improved the prognosis of patients with advanced cancer in recent years, and the number of patients with bone metastasis is likely to increase with the prognosis of cancer. The most frequent site of metastases in the bone is the spine. Fracture-related pain and paralysis often necessitating emergency surgery by a spine surgeon because of an extension to the spinal cord greatly impair the quality of life. In recent years, researchers have reported on the need for multidisciplinary approach by diverse professionals, such as orthopedic surgeons, oncologists, and radiologists. However, it is difficult to hold frequent meetings because a multidisciplinary approach requires the participation and cooperation of numerous professionals. Therefore, instead of the multidisciplinary approach, we decided to open a specialized outpatient clinic on bone metastasis. We aimed to evaluate the usefulness of a specialized outpatient clinic on bone metastasis, initiated instead of the multidisciplinary approach.

Methods: This retrospective study enrolled patients with vertebral metastasis of carcinoma, diagnosed and surgically treated by spine surgeons at our hospital between May 2017 and April 2021. All patients who received radiotherapy for vertebral metastasis before the surgery or had brain-derived neurological deficit that affected their gait function were excluded. We eventually included 31 patients with vertebral metastasis, undergoing surgical treatment (16 men and 15 women, mean age: 67.3 years, and range: 42–83 years). We inspected the patient records to collect information on their regarding age, sex, the location of the primary tumor, the site of spinal lesion, a history of primary tumor treatment, paralysis or bladder and rectal disorder, a history of denosumab treatment, the period from spine surgeon consultation to surgery, surgical method, surgery time, operation room leaving time, intraoperative bleeding volume, and preoperative embolization. The specialized outpatient clinic on bone metastasis was initiated at our hospital in May 2019. We divided the patients into two groups, namely 2 years until April 2019 (Pre group) and 2 years after May 2019 (Post group), and we compared the clinical characteristics and information on surgery between the groups. In addition, we excluded patients who had not been treated for original carcinoma at our hospital or those not diagnosed with the primary tumor, and we compared only patients who were being treated for primary tumors at our hospital. Furthermore, we examined factors that affected the period from consulting the spine surgeon to the surgery, in addition to those that delayed leaving the operating room.

Results: The mean period from spine surgeon consultation to the surgery for all patients was 9.3±10.6 days (range: 0–46 days). Eighteen patients were being treated for primary tumors at our hospital. The post group demonstrated a longer period from spine surgeon consultation to surgery than the pre group (p=0.0498). Only in patients treated for primary tumors at our hospital, the period from spine surgeon consultation to surgery in the post group was significantly longer than that in the pre group (p=0.0129). The multivariate logistic regression analysis revealed that the period from spine surgeon consultation to surgery was significantly associated with visits to the specialized outpatient clinic (p=0.0460). In contrast, no obvious factors affected the operation leaving time.

Conclusion: The specialized outpatient clinic on bone metastasis had the possibility of reducing the burden on spinal surgeons by providing a margin for patients with spinal metastasis who required surgery. Because the number of patients with bone metastases is expected to increase, it is important to create a new system that will lead to early intervention for patients with bone metastases.