Quantification of vertebral involvement in metastatic spinal disease

Abstract

Introduction: For patients with a solitary and well-delimitated spinal metastasis that resides inside the vertebral body, without vertebral canal invasion, and who are in good general health with a long life expectancy, en bloc spondylectomy/total vertebrectomy combined with the use of primary stabilizing instrumentation has been advocated. However, clinical experience suggests that these qualifying conditions occur very rarely.

Objective: The purpose of this paper is to quantify the distribution of vertebral involvement in spinal metastases and determine the frequency with which patients can be considered candidates for radical surgery (en bloc spondylectomy).

Methods: Consecutive patients were classified accordingly to Enneking's and Tomita's schemes for grading vertebral involvement of metastases.

Results: Fifty-one (51) consecutive patients were evaluated. Eighty-three percent of patients presented with the involvement of multiple vertebral levels and/or spinal canal invasion.

Conclusion: Because of diffuse vertebral involvement of metastases, no patients in this sample were considered to be candidates for radical spondylectomy of vertebral metastasis.

Keywords: Cancer; neoplasm metastasis; prognosis; spine; spondylectomy; surgical procedures..

Fig. (1)

Diagram based on Enneking’s classification of benign tumors. The top three diagrams represent benign tumors and the lower four, malignant tumors. 1, tumor capsule; 2, tissue reaction; 3, tumor island within adjacent tissue reaction; 4, skip metastasis.

Fig. (2)

Diagram based on Tomita´s classification of vertebral metastasis.

Fig. (3)

Neurological patient presentation based on Frankel scale. Grade A: Complete neurological injury with no motor or sensory function clinically detected below the level of the injury. Grade B: Preserved sensation only; no motor function clinically detected below the level of the injury; sensory function remaining below the level of the injury but may include only partial function. Grade C: Preserved motor non-functional. Grade D: Useful motor function below the level of the injury; patient can move lower limbs and walk with or without aid but does not have a normal gait or strength in all motor groups. Grade E: Normal motor functioning.

Fig. (4)

Number of patients corresponding to each grade of the Karnovsky scale (KS).

Fig. (5)

Number of patients with vertebral metastasis from each primary tumor type.

Fig. (6)

Multiple vertebral involvement (Tomita’s grade 7).

Fig. (7)

All spine is involved in vertebral metastasis.

Fig. (8)

Classification of patients according to Tomita’s vertebral involvement scale.