Treatment of neoplastic spinal cord compression: results of a prospective study

Evidence-based review of the surgical management of vertebral column metastatic disease

Object

Significant controversy exists over the most appropriate treatment for patients with metastatic disease of the vertebral column. Treatment options include surgical intervention, radiotherapy, or a combination of the two; nevertheless, a standard of care that yields the best survival, outcome, and quality of life has not been established. The purpose of this review was to determine the foundation in the literature of views favoring surgical intervention for spinal metastatic disease.

Methods

A search of the English-language literature published between 1964 and 2003 was performed for the subject of spinal metastatic disease. Papers were selected based on the inclusion criteria described, and evidentiary information was compiled and graded using previously described methods.

Conclusions

Although there is insufficient evidence to support a standard for surgical treatment in patients with metastatic spinal disease, the authors present guidelines and recommendations based on the evidence provided by the current literature.

Cervical spinal metastasis: anterior reconstruction and stabilization techniques after tumor resection

Object

In a review of the literature, the authors provide an overview of various techniques that have evolved for reconstruction and stabilization after resection for metastatic disease in the subaxial cervical spine.

Methods

Reconstruction and stabilization of the cervical spine after vertebral body (VB) resection for metastatic tumor is an important goal in the surgical management of spinal metastasis. Generally, the VB defect is reconstructed with bone autograft or allograft, polymethylmethacrylate (PMMA), interbody spacers, and/or cages. In cases of PMMA-assisted reconstruction, internal devices are used to augment the fixation of PMMA. Stabilization is then achieved with anterior instrumentation, usually an anterior cervical locking plate. In some cases, posterior instrumentation may be necessary to supplement the anterior construct.

Conclusions

Anterior cervical corpectomy followed by reconstruction and stabilization is an effective strategy in the management of spinal metastases in patients.

Management of metastatic tumors of the spine: strategies and operative indications

The spinal column is the most frequent site of bone metastasis in the body. Spine surgeons are often involved in the care of these patients only after nonoperative management has failed. Because surgery has been viewed as no better than radiotherapy in the treatment of metastasis of the spine, it has only been used as a salvage approach. These views are based on a body of literature in which laminectomy combined with radiotherapy was compared with radiotherapy alone. Anterior approaches to the spine are now popular and familiar to most surgeons. These approaches allow direct access to the metastatic lesion, reconstruction of the anterior vertebral column, and the placement of anterior instrumentation. Outcomes are frequently much better when this combined treatment is used instead of radiotherapy alone. In selected patients, surgery may be desired as first-line therapy before radio- or chemotherapy has been initiated. The controversy surrounding surgery for metastatic spinal disease is reviewed. Treatment strategies, both operative and nonoperative, are presented. Indications and strategies for surgery are also presented, and the supporting literature is reviewed.

Perioperative complications with costotransversectomy and anterior approaches to thoracic and thoracolumbar tumors

OBJECT

Anterior decompression and stabilization for thoracic spinal tumors often involves a thoracotomy and can be associated with surgical approach-related complications. An alternative to thoracotomy is surgery via a costotransversectomy exposure. To delineate the risks of surgery, the authors reviewed their prospective database for patients who had undergone surgery via either of these approaches for thoracic or thoracolumbar tumors. The complications were recorded and graded based on severity and risk of impact on patient outcome.

METHODS

Between September 1995 and April 2001, the authors performed 29 costotransversectomies (Group 1) and 18 thoracolumbar or combined (Group 2) approaches as initial operations for thoracic neoplasms. The age, sex, preoperative motor score, and preoperative Frankel grade did not significantly differ between the groups. In the costotransversectomy group there were greater numbers of metastases, upper thoracic procedures, and affected vertebral levels; additionally, the comorbidity rate based on Charlson score, was higher. The mean Frankel grades at discharge were not significantly different whereas the discharge motor and last follow-up motor scores were better in Group 2. There were 11 Group 1 and seven Group 2 patients who suffered at least one complication. The number or patients with complications, the mean number of complications, and severity of complications did not differ between the groups.

CONCLUSIONS

Compared with anterior or combined approaches, the incidence and severity of perioperative complications in the surgical treatment of thoracic and thoracolumbar spinal tumors is similar in patients who undergo costotransversectomy. Costotransversectomy may be the preferred operation in patients with significant medical comorbidity or tumors involving more than one thoracic vertebra.

Evaluation and treatment of spinal metastases: an overview

Metastases to the spine are a common and somber manifestation of systemic neoplasia. The incidence of spinal metastases continues to increase, likely a result of increasing survival times for patients with cancer. Historically, surgery for spinal metastases has consisted of simple decompressive laminectomy. Results obtained in retrospective case series, however, have shown that this treatment provides little benefit to the patient. With the advent of better patient-related selection practices, in conjunction with new surgical techniques and improved postoperative care, the ability of surgical therapy to play an important and beneficial role in the multidisciplinary care of cancer patients with spinal disease has improved significantly. Controversy remains, however, with respect to the relative merits of surgery, radiotherapy, chemotherapy, or a combination of these treatments.

In this topic review, the literature on spinal column and spinal cord metastases is collated to provide a description of the presentation, investigations, indications for surgical therapy, and the role of adjuvant cancer therapies for patients with spinal metastases. In addition, the authors discuss the different surgical strategies available in the armamentarium of the neurosurgeon treating patients with spinal metastasis.

Spinal stabilization by using crossed-screw anterior-posterior fixation after multisegmental total spondylectomy for thoracic chondrosarcoma. Case report

The authors describe the case of a 41-year-old man with high-grade chondrosarcoma who presented with a paraspinous mass extending into three thoracic vertebrae (T10-12). Crossfixed long anterior and posterior instrumentation was placed after three complete spondylectomies (T10-12). This technique augments spinal stability with an outrigger effect by using crossfixators placed between paired dorsal rods, as well as between the anterior and posterior hardware components. This technique may be used as an alternative when multiple vertebrae or all three spinal columns are involved by radioresistant malignant tumors in patients in whom there is a relatively long life expectancy.

Metastatic renal cell carcinoma of the spine: surgical treatment and results

OBJECT

Renal cell carcinoma (RCC) is an aggressive malignancy that frequently metastasizes. When RCC metastasizes to the spine, significant pain and neurological dysfunction often follow. Because systemic therapy and radiotherapy have a limited effect in controlling spinal disease, surgery is frequently required; however, there are very few published series specifically addressing the role and benefits of the surgical treatment for this disease. The authors conducted a retrospective study to review their experience with the surgical treatment of metastatic RCC of the spine, paying particular attention to methodology and patient neurological status, pain relief, and survival.

METHODS

Between January 1993 and April 1999, 79 patients (63 men and 16 women patients; average age 55 years, range 16-82 years) underwent 107 spinal operations for metastatic RCC. Indications for surgery included disabling pain (94 [88%] of 107 procedures) and/or neurological dysfunction (55 [51%] of 107 procedures). The anatomical location and extent of tumor determined the choice of an anterior, posterior, or combined surgical approach. Internal fixation was performed in all but three patients. Preoperative embolization was required in approximately one half of the patients. Radiotherapy was performed in 40 patients prior to surgery, and immuno- and chemotherapy were administered in 70 patients either pre- or postoperatively. After an average follow-up duration of 15 months, 57 patients had died. Kaplan-Meier analysis revealed a median postoperative survival of 12.3 months. Significant pain reduction, as indicated by a visual analog pain scale, was achieved in 84 (89%) of the 94 cases presenting with disabling pain. Neurological improvement was seen in 36 (65%) of the 55 patients. The major morbidity and 30-day mortality rates were 15% (16 of 107 procedures) and 2% (two of 107 procedures), respectively.

CONCLUSIONS

In selected patients with metastatic RCC of the spine, resection followed by stabilization can provide pain relief and neurological preservation or improvement.

Coaxial double-lumen methylmethacrylate reconstruction in the anterior cervical and upper thoracic spine after tumor resection

OBJECT

A unique method of anterior spinal reconstruction after decompressive surgery was used to prevent methylmethacrylate-dural contact in cancer patients who underwent corpectomy. The purpose of this study was to assess the efficacy and stability of polymethylmethacrylate (PMMA) anterior surgical constructs in conjunction with anterior cervical plate stabilization (ACPS) in these patients.

METHODS

Approximately 700 patients underwent spinal surgery at The University of Texas M. D. Anderson Cancer Center over a 4-year period. The authors conducted a retrospective outcome study for 29 of these patients who underwent anterior cervical or upper thoracic tumor resections while in the supine position. These patients were all treated using the coaxial, double-lumen, PMMA technique for anterior spinal reconstruction with subsequent ACPS. No postoperative external orthoses were used. Twenty-seven patients (93%) harbored metastatic spinal lesions and two (7%) harbored primary tumors. At 1 month postsurgery, significant improvement was seen in spinal axial pain (p<0.001), radiculopathy (p<0.001), gait (p = 0.008), and Frankel grade (p = 0.002). A total of nine patients (31%) underwent combined anterior-posterior 360 degrees stabilization. Twenty-one patients (72%) experienced no complications. Complications related to instrumentation failure occurred in only two patients (7%). There were no cases in which the patients' status worsened, and there were no neurological complications or infections. The median Kaplan-Meier survival estimate for patients with spinal metastases was 9.5 months. At the end of the study, 13 patients (45%) had died and 16 (55%) were alive. Postoperative magnetic resonance images consistently demonstrated that the dura and PMMA in all patients remained separated.

CONCLUSIONS

The anterior, coaxial, double-lumen, PMMA reconstruction technique provides a simple means of spinal cord protection in patients in the supine position while undergoing surgery and offers excellent results in cancer patients who have undergone cervical vertebrectomy.

Transthoracic vertebrectomy for metastatic spinal tumors

OBJECT

Anterior approaches to the spine for the treatment of spinal tumors have gained acceptance; however, in most published reports, patients with primary, metastatic, or chest wall tumors involving cervical, thoracic, or lumbar regions of the spine are combined. The purpose of this study was to provide a clear perspective of results that can be expected in patients who undergo anterior vertebral body resection, reconstruction, and stabilization for spinal metastases that are limited to the thoracic region.

METHODS

Outcome is presented for 72 patients with metastatic spinal tumors who were treated by transthoracic vertebrectomy at The University of Texas M. D. Anderson Cancer Center. The predominant primary tumors included renal cancer in 19 patients, breast cancer in 10, melanoma or sarcoma in 10, and lung cancer in nine patients. The most common presenting symptoms were back pain, which occurred in 90% of patients, and lower-extremity weakness, which occurred in 64% of patients. All patients underwent transthoracic vertebrectomy, decompression, reconstruction with methylmethacrylate, and anterior fixation with locking plate and screw constructs. Supplemental posterior instrumentation was required in seven patients with disease involving the cervicothoracic or thoracolumbar junction, which was causing severe kyphosis. After surgery, pain improved in 60 of 65 patients. This improvement was found to be statistically significant (p < 0.001) based on visual analog scales and narcotic analgesic medication use. Thirty-five of the 46 patients who presented with neurological dysfunction improved significantly (p < 0.001) following the procedure. Thirty-three patients had weakness but could ambulate preoperatively. Seventeen of these 33 regained normal strength, 15 patients continued to have weakness, and one patient was neurologically worse postoperatively. Of the 13 preoperatively nonambulatory patients, 10 could walk after surgery and three were still unable to walk but showed improved motor function. Twenty-one patients had complications ranging from minor atelectasis to pulmonary embolism. The 30-day mortality rate was 3%. The 1-year survival rate for the entire study population was 62%.

CONCLUSIONS

These results suggest that transthoracic vertebrectomy and spinal stabilization can improve the quality of life considerably in cancer patients with spinal metastasis by restoring or preserving ambulation and by controlling intractable spinal pain with acceptable rates of morbidity and mortality.

Development of vertebral fractures in patients with multiple myeloma: does MRI enable recognition of vertebrae that will collapse?

PURPOSE

We assessed the relationship between the presence and size of focal marrow abnormalities detected with MRI in vertebral bodies and the subsequent occurrence of vertebral fractures at follow-up in patients with multiple myeloma (MM).

METHOD

We reviewed 179 follow-up MR examinations of the thoracic and lumbar spine prospectively obtained in 37 patients with Stage 3 MM. For each of 131 vertebral bodies that fractured during follow-up, the status of the vertebral bone marrow was assessed on the last MR study obtained at a mean time interval of 4 months prior to fracture occurrence. When focal lesions were observed before fracture in vertebral bodies that later collapsed, their size was compared with that of the contemporary lesions observed in vertebrae that did not collapse.

RESULTS

Of 131 fractures, 82 (63%) appeared in vertebrae previously free of focal bone marrow abnormality at MRI and 49 (37%) appeared in vertebrae in which focal lesions were present on the previous MR study. The size of the lesions that preceded fractures (median 15 mm; range 6-50 mm) was not statistically different from the size of the contemporary lesions (median 15 mm; range 5-60 mm) that did not lead to fracture (p > 0.30).

CONCLUSION

This study in patients with MM suggests a lack of correlation between the preexistence of focal vertebral marrow lesions detected with MRI and the subsequent development of vertebral fractures.

Indications and results of combined anterior-posterior approaches for spine tumor surgery

Spinal instrumentation currently allows gross-total resection and reconstruction in cases of malignancies at all levels of the spine. The authors analyzed the results in 110 patients who underwent surgery for primary and metastatic spinal tumors over a 5-year period (1989-1993) at a single institution. Major primary sites of tumor included breast (14 cases), chordoma (14 cases), lung (12 cases), kidney (11 cases), sarcoma (13 cases), plasmacytoma (10 cases), and others (36 cases). Prior to surgery, 55 patients (50%) had received prior treatment. Forty-eight patients (44%) were nonambulatory, and severe paraparesis was present in 20 patients. Fifty-three patients (48%) underwent combined anterior-posterior resection and instrumentation. 33 (30%) underwent anterior resection with instrumentation, 18 (16%) underwent anterior or posterior resection alone, and the remaining six patients (5%) underwent posterior resection and instrumentation. Major indications for anterior-posterior resection included three-column involvement, high-grade instability, involvement of contiguous vertebral bodies, and solitary metastases. Postoperatively, 90 patients improved neurologically. The overall median survival was 16 months, with 46% of patients surviving 2 years. Fifty-three patients (48%) suffered postoperative complications. Despite the high incidence of complications, the majority of patients reported improvement in their quality of life at follow-up review. Our findings suggest that half of all patients with spinal malignancies require combined anterior-posterior surgery for adequate tumor removal and stabilization.

Single-stage posterior vertebrectomy and replacement combined with posterior instrumentation for spinal metastasis

The authors present a series of 25 patients who underwent single-stage complete spondylectomy, vertebral body reconstruction, and posterior segmental spinal stabilization for malignant metastatic disease involving multiple columns of the thoracolumbar spine. Patients were selected for this approach primarily because they were poor candidates for a transcavitary or lateral extracavitary approach or because the tumor involved both anterior and posterior columns of the spine. The operative approach used combines radical local resection of tumor via a bilateral transpedicular route, methylmethacrylate vertebral body reconstruction, and Luque rectangle stabilization in a single operation. Following surgery, the majority of patients experienced improvement in their neurological status, reduction in pain, or both. Most patients were functionally improved, or at least no worse, and spinal alignment was maintained in all. There was one local recurrence in a long-term survivor. Complications included cerebrospinal fluid fistulas, migrating graft material, and wound healing problems. The authors conclude that this surgical approach is safe and feasible for the radical resection of vertebral metastasis when combined with reconstruction and stabilization. This technique represents a useful alternative to other commonly used surgical approaches for the treatment of spinal metastases, and it should aid surgeons in selecting the optimum approach for individual patients.

Indications and results of combined anterior-posterior approaches for spine tumor surgery

Spinal instrumentation currently allows gross-total resection and reconstruction in cases of malignancies at all levels of the spine. The authors analyzed the results in 110 patients who underwent surgery for primary and metastatic spinal tumors over a 5 year period (1989–1993) at a single institution. Major primary sites of tumor included breast (14 cases), chordoma (14 cases), lung (12 cases), kidney (11 cases), sarcoma (13 cases), plasmacytoma (10 cases), and others (36 cases). Prior to surgery, 55 patients (50%) had received prior treatment. Forty eight patients (44%) were nonambulatory, and severe paraparesis was present in 20 patients. Fifty three patients (48%) underwent combined anterior-posterior resection and instrumentation, 33 (30%) underwent anterior resection with instrumentation, 18 (16%) underwent anterior or posterior resection alone, and the remaining six patients (5%) underwent posterior resection and instrumentation. Major indications for anterior-posterior resection included three-column involvement, high-grade instability, involvement of contiguous vertebral bodies, and solitary metastases. Postoperatively, 90 patients improved neurologically. The overall median survival was 16 months, with 46% of patients surviving 2 years. Fifty-three patients (48%) suffered postoperative complications. Despite the high incidence of complications, the majority of patients reported improvement in their quality of life at follow-up review. Our findings suggest that half of all patients with spinal malignancies require combined anterior-posterior surgery for adequate tumor removal and stabilization.

Vertebral body reconstruction with a modified Harrington rod distraction system for stabilization of the spine affected with metastatic disease

Anterior spinal decompression has become widely used for neoplasia arising from the vertebral bodies. Replacement for the resected vertebral body must achieve spinal stability, restitution of lost height, correction of kyphotic deformities, and allow for early ambulation. A spinal fixator based on the Harrington ratchet locking system was found to fulfill this requirement. The fixator, its technique of implementation, and surgical results in 10 patients are described.

Unilateral posterolateral decompression without stabilization for neurological palliation of symptomatic spinal metastasis in debilitated patients

Patients with symptomatic spinal metastases and limited life expectancy are often too debilitated to withstand anterior or posterolateral spinal cord decompression and segmental stabilization. More limited surgery aiming solely at preservation or restoration of neurological function and relief from pain offers the potential for significant improvement in the quality of remaining life without incurring undue perioperative morbidity and mortality. Eight patients with spinal metastases and limited life expectancy underwent a unilateral transpedicular decompression procedure on their most symptomatic side and/or the side of maximum tumor involvement. All patients were neurologically improved within the 1st postoperative week; all were ambulatory and continent postoperatively. Postoperatively, all five patients with preoperative motor deficits demonstrated increased motor strength, and the three patients with predominant radicular pain reported marked improvement. There were no perioperative deaths and two transient perioperative complications. The average length of hospitalization was 6 days for patients without complications and 10 days for the entire group. Unilateral transpedicular decompression without stabilization is an effective and safe method for palliating symptomatic spinal metastases in debilitated patients with widespread malignancy and limited life expectancy. This therapeutic option should be considered in select cases as an alternative to either nonoperative management or anterior or posterolateral decompression and segmental stabilization.

Magnetic resonance imaging in spinal emergency

We studied the diagnostic value of MRI in spinal emergency. One hundred patients were analyzed retrospectively and the MR-findings were compared with operative results or autopsy whenever available. The advantages of MRI compared to CT and conventional myelography are discussed. The limitations of MRI are addressed and the important features of appropriate diagnostic procedure are outlined with special attention to neurosurgical requirements.

Prognostic factors in anterior decompression for metastatic cord compression. An analysis of results

During the 10-year period 1981-1990, 59 patients suffering from spinal cord or cauda equina compression underwent anterior spinal decompression and in most cases spinal restabilization with methylmethacrylate cement and/or instrumentation. Follow-up in 55 patients showed that 75% were improved neurologically by the procedure, one-third of these showing complete recovery from the spinal cord compression. The results in younger female patients suffering from metastatic breast cancer were considerably better than those of older men with prostatic metastases. Other genitourinary system tumors also had a relatively poorer prognosis. There was a significantly better result for metastatic lesions of the thoracic or thoracolumbar spine than for lesions in the lumbar spine causing cauda equina paralysis.