Surgical treatment of bone metastasis from osteophilic cancer. Results in 401 peripheral and spinal locations

Abstract

Introduction: Peripheral and spinal bone metastases arise mainly from 5 osteophilic cancers: lung, prostate, kidney, breast and thyroid. Few studies combined results for the two types metastatic location (peripheral and spinal). Therefore we performed a multicenter retrospective study of surgically managed peripheral and spinal bone metastases to assess: (1) global function at a minimum 1 year's follow-up and; (2) factors affecting survival.

Hypothesis: Global function is improved by surgery, with acceptable survival.

Material and method: Between 2015 and 2016, 386 patients were operated on in 11 centers for 401 metastases: 231 peripheral, and 170 spinal. Mean age was 62.6±12.5 years in the 212 female patients (54%) versus 66.4±11.5 years in the 174 males (46%) (p=0.001). Pre- to postoperative comparison was made on pain on VAS (visual analog scale), WHO (World Health Organization) score, Karnofsky score, walking and global upper-limb function. Survival was estimated at 4 years' follow-up.

Results: The most frequent locations were in the femur (n=146, 36%) and thoracic spine (n=107, 27%). The primary cancer was revealed by the metastasis in 82 patients (21%). There were 55 general complications (14%) and 48 local complications (12%). Twenty-one patients (5.4%) died during the first month. VAS and Karnofsky sores improved: respectively, 6.6±2.3 vs. 3.4±2.1 (p<0.001) and 65±14 vs. 72±20 (p=0.01). Walking, upper-limb function and Frankel grade improved in respectively 49/86 (57%), 19/29 (66%) and 31/84 (37%) patients. Median survival was 13.3 months (95% CI: 10.8-17.1), and was related to the primary (log-rank, p<0.001): lung 6.5 months (95% CI: 5.2-8.9), prostate 11.1 months (95% CI: 5.3-43.6), kidney 12.9 months (95% CI: 8.4-22.6), breast 26.5 months (95% CI: 19.0-34.0), and thyroid 49.0 months (95% CI: 12.2-NA). On multivariate analysis, independent factors for death comprised internal fixation rather than prosthesis (OR=2.20; 95% CI: 1.59-3.04 (p<0.001)), high preoperative ASA score (OR=1.78; 95% CI: 1.40-2.28 (p<0.001)), preoperative chemotherapy (OR=1.26; 95% CI: 1.13-1.41 (p<0.001)) and major visceral metastasis (lung, brain, liver) (OR=11.80; 95% CI: 5.21-26.71 (p<0.001)).

Conclusion: Although function improved only slightly, pain relief and maintained autonomy suggest enhanced comfort in life, confirming the study hypothesis only partially. Factors affecting survival and clinical results argue for preventive surgery when possible, before general health status deteriorates.

Level of evidence: IV; retrospective observational.

Keywords: Bone metastasis; Osteophilic cancer; Pathological fracture; Surgery; Survival.