The NOMS framework: approach to the treatment of spinal metastatic tumors

Abstract

Background: Spinal metastases frequently arise in patients with cancer. Modern oncology provides numerous treatment options that include effective systemic, radiation, and surgical options. We delineate and provide the evidence for the neurologic, oncologic, mechanical, and systemic (NOMS) decision framework, which is used at Memorial Sloan-Kettering Cancer Center to determine the optimal therapy for patients with spine metastases.

Methods: We provide a literature review of the integral publications that serve as the basis for the NOMS framework and report the results of systematic implementation of the NOMS-guided treatment.

Results: The NOMS decision framework consists of the neurologic, oncologic, mechanical, and systemic considerations and incorporates the use of conventional external beam radiation, spinal stereotactic radiosurgery, and minimally invasive and open surgical interventions. Review of radiation oncology and surgical literature that examine the outcomes of treatment of spinal metastatic tumors provides support for the NOMS decision framework. Application of the NOMS paradigm integrates multimodality therapy to optimize local tumor control, pain relief, and restoration or preservation of neurologic function and minimizes morbidity in this often systemically ill patient population.

Conclusion: NOMS paradigm provides a decision framework that incorporates sentinel decision points in the treatment of spinal metastases. Consideration of the tumor sensitivity to radiation in conjunction with the extent of epidural extension allows determination of the optimal radiation treatment and the need for surgical decompression. Mechanical stability of the spine and the systemic disease considerations further help determine the need and the feasibility of surgical intervention.

Figure 1.

A six-point grading system by the Spine Oncology Study Group [5] uses axial T2-weighted images at the site of most severe compression to describe the degree of epidural spinal cord compression: 0, tumor is confined to bone only; 1, tumor extension into the epidural space without deformation of the spinal cord; 2, spinal cord compression but cerebrospinal fluid is visible; and 3, spinal cord compression without visible cerebrospinal fluid. The grade 1 delineation is further subdivided into 1a–1c: 1a, epidural impingement but no deformation of the thecal sac; 1b, deformation of the thecal sac but without spinal cord abutment; and 1c, deformation of the thecal sac with spinal cord abutment but without compression.

Figure 2.

This 67-year-old man with no cancer history presented with back pain. Pain was secondary to an L1 tumor (A). Percutaneous needle biopsy provided the diagnosis of multiple myeloma. The patient was started on high-dose dexamethasone and underwent conventional external beam radiation. (B): The epidural tumor entirely resolved 11 weeks later.

Figure 3.

Imaging studies from a 77-year-woman. (A): The patient had renal cell carcinoma with T12 metastasis that was causing radicular pain. (B): The patient underwent single-fraction stereotactic radiosurgery (2400 cGy). By 2 weeks after treatment, the pain completely resolved and the patient did not require pain medications. (C): Follow-up magnetic resonance imaging performed 3 months after stereotactic radiosurgery showed significant reduction in tumor size.

Figure 4.

Imaging studies from a 65 year-old man with renal cell carcinoma metastatic to T10 resulting in Grade 3 epidural spinal cord compression and myelopathy (A). T10 laminectomy, bilateral T9–T10 and T10–T11 facetectomies, transpedicular resection of ventral epidural tumor, and T8–T12 posterolateral instrumentation and fusion were performed (B). Postoperative myelogram shows complete circumferential decompression of the spinal cord (C). Postoperatively the patient received 2850 cGy in three fractions.

Figure 5.

Imaging studies from a 60-year-old woman. (A): The patient had colon adenocarcinoma metastatic to L2, resulting in severe mechanical radiculopathy. (B): The tumor was lytic, with extension into bilateral posterior elements. (C): L2 laminectomy and T12–L4 posterolateral instrumentation and fusion were performed, with complete resolution of the mechanical pain.

Figure 6.

Schematic depiction of the neurologic, oncologic, mechanical, and systemic (NOMS) decision framework. Abbreviations: cEBRT, conventional external beam radiation; SRS, stereotactic radiosurgery.