Abstract:

Objective

To explore the outcomes of surgery and prognostic factors on survival in patients with spinal metastases secondary to renal carcinoma.

Methods

A retrospective analysis was performed on 16 patients with renal carcinoma spinal metastases who were undergone surgeries at Tianjin Hospital from December 2019 to March 2023. Clinical data， KPS score， NRS score， Frankel grade， postoperative treatment measures， local recurrence rate and survival status of the patients were collected. The median survival time and postoperative survival rates were estimated by Kaplan-Meier method.A systematic review was conducted by searching the PubMed， Embase， and Cochrane Library databases. The related clinical studies on surgical treatment of spinal metastases from renal carcinoma were collected from 1964 to October 12，2023.After evaluating the quality of the literatures，a descriptive analysis was performed.

Results

A total of 16 patients were included in the retrospective analysis，all of whom were male，with an average age of 62.0±9.5 years.Among all the patients， 5 underwent en bloc spondylectomy （TES） （31.25%）， 9 underwent piecemeal resection（56.25%），and 2 underwent percutaneous vertebroplasty（PVP）（12.5%）.Preoperative embolization was performed in 3 among the 14 patients who underwent open surgery（21.43%），and the mean intraoperative blood loss was 1 707.19±1 512.14 ml. The preoperative KPS score was 51.87±20.40 and significantly increased to 64.38±27.80 postoperatively（P=0.052）.The preoperative NRS score was 6.2±1.4 and decreased to 2.5±2.0 postoperatively （P＜0.001）.There were 2 patients of Frankel Grade A， 1 patient of Grade C， 7 patients of Grade D and 6 patients of Grade E before surgery. Postoperatively， there were 3 patients of Grade A，1 patient of Grade B，3 patients of Grade D and 9 patients of Grade E，but without statistically significant difference （P=0.792）. The median follow-up time was 23 months， with 8 deaths by the last followup. The median survival time was 26.0 months （95% CI： 3.0， 20.1）， The overall survival rates at 1y， 2y and 3y were 88%、63 and 31% respectively.After screening， 15 studies were included in this systematic review involving a total of 1007 patients.Six studies found that surgery effectively relieved pain in patients with renal carcinoma spinal metastases， while seven studies demonstrated that surgery improved neurological function in patients with metastatic epidural spinal cord compression （MESCC）. However， the conclusions on whether different surgical types could bring survival benefit and whether preoperative embolization could reduce intraoperative blood loss were conflicted. The postoperative median overall survival ranged from 6 to 34.7 months.Multiple studies confirmed that visceral and multiple bone metastases were negative prognostic factors affecting the survival of patients with renal carcinoma spinal metastases.

Conclusions

Surgery can effectively alleviate pain and facilitate the recovery of spinal cord function for the patients with renal carcinoma spinal metastases.The main negative prognostic factors affecting the overall survival are the presence of visceral metastasis and multiple bone metastases.

Key words: Spinal metastases, Renal carcinoma, Surgery, Prognosis