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 Table of Contents  
SYMPOSIUM - METASTATIC SPINAL TUMORS
Year : 2022  |  Volume : 5  |  Issue : 2  |  Page : 193-198

Outcomes of surgical treatment in spinal metastasis


Department of Spine Surgery, Christian Medical College, Vellore, Tamil Nadu, India

Date of Submission16-Feb-2022
Date of Decision09-Apr-2022
Date of Acceptance21-Apr-2022
Date of Web Publication08-Jun-2022

Correspondence Address:
Venkatesh Krishnan
Department of Spine Surgery, Christian Medical College, Vellore, Tamil Nadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/isj.isj_16_22

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  Abstract 

With increase in the elderly population and improved survival among patients with malignancies, the rates of patients presenting with metastatic involvement of the spine is on the rise. Surgical management of spinal metastasis requires a multidisciplinary approach and surgery is a key component of multimodality management of metastatic spinal lesions. A PubMed search of relevant articles was performed and a narrative review of available pertinent literature in English language is presented.

Keywords: Outcomes, spinal metastasis, surgery


How to cite this article:
Ghimire N, Krishnan V. Outcomes of surgical treatment in spinal metastasis. Indian Spine J 2022;5:193-8

How to cite this URL:
Ghimire N, Krishnan V. Outcomes of surgical treatment in spinal metastasis. Indian Spine J [serial online] 2022 [cited 2022 Jul 1];5:193-8. Available from: https://www.isjonline.com/text.asp?2022/5/2/193/346966




  Introduction Top


Before the introduction of radiation therapy, the only treatment for management of spinal metastasis with epidural compression was decompression surgery in the form of simple laminectomy. With widespread use of radiation therapy in oncology, surgical management of spine metastasis fell out of favor because the neurological outcomes of laminectomy with radiotherapy were no better than radiation therapy alone.[1],[2] It has to be noted that the epidural compression caused by anterior metastatic involvement of the vertebral body is poorly addressed by a posterior decompressive procedure like laminectomy. Later studies demonstrated that improved neurological function can be achieved with surgical procedures that approached vertebral body directly for anterior decompression and reconstruction.[3],[4]

In a landmark randomized trial in 2005, Patchell et al.[5] compared the results of surgical decompression and radiation therapy with radiation alone. Surgical decompression was circumferential, anterior or posterior depending upon the extent of epidural compression followed by reconstruction with or without instrumentation. The trial had to be stopped prior to completion because of proven superiority of surgical management in combination with radiation over radiation alone in terms of neurological improvement. The results of this trial led to wider acceptance of surgical treatment for spinal metastasis with Metastatic Spinal Cord Compression (MSCC).

Treatment of spinal metastasis is a continuously evolving discipline. There has been a significant transformation over the years in the approach for overall management of neoplasms and also those with spinal metastasis with development of targeted radiation therapy techniques, advances in medical management and immunotherapy, better understanding of genomic and molecular biology of tumors.[6] In order to equal such advances, the role of surgery needs to be continuously reassessed to select the best treatment approach based on available evidence. In this study we primarily focus on the outcomes with regards to patient survival, neurological outcome and restoration of ambulatory capacity, improvement of pain, morbidity and complications and patient related outcomes and impact on quality of life following surgery in spinal metastasis.


  Materials and Methods Top


A PubMed search was made using search strategies ((“Spine” [Mesh]) AND “Neoplasm Metastasis” [Mesh]), [(“Patient Reported Outcome Measures” [Mesh]) AND “Spinal Neoplasms” [Mesh]) AND “Spinal Neoplasms/surgery” [Mesh]] and the obtained results were parsed to identify articles that looked into surgical management of spinal metastasis. Only articles published in English were included. Original articles, systematic reviews and meta-analysis, narrative reviews were all considered. The references of the above mentioned articles were also looked into to identify relevant articles and these were included in the literature search for this study. Based on this 33 articles were chosen to study the various parameters which affects the outcomes following surgery in spinal metastasis.

Survival

Patient survival is a primary consideration in choosing surgical treatment for a patient with spinal metastasis. Various studies have attempted to evaluate the factors that have an effect on survival of the patients after surgery.

Primary tumor type, other oncological factors and prognostic score systems

Gokaslan et al.[4] reported 72 patients with thoracic spine metastasis caused by different primary tumor types and treated surgically with transthoracic vertebrectomy followed by anterior reconstruction with PMMA cement and stabilization in their study. The 1-year survival rates for different histological tumor types were reported in their study as follows: renal cell cancer 65%, breast cancer 63%, lung cancer 55% and melanoma or sarcoma 52%.

Presence of visceral and extraspinal bony metastasis has been found to have poor prognosis, whereas less than three spinal metastasis have been suggested to be good prognostic factor on patient survival.[7],[8],[9],[10],[11],[12] In a large multicenter prospective study of 922 patients Choi et al.[12] reported that primary tumor type, presence of visceral metastasis and the number of spinal metastasis were significant predictive factors of patient survival for patients with symptomatic spinal metastasis.

Postoperative adjuvant therapy also improved patient survival as suggested by various studies.[10],[13] Recurrence after radiotherapy was found to be poor prognostic factor after surgery.[14] In patients with carcinoma prostate with spinal metastasis hormone sensitivity was found to be the most important factor for survival with good prognosis.[11]

Revised Tokuhashi scoring system[15] incorporates primary tumor type as a component and gives the following scores for different primary tumor types: 0 (lung, osteosarcoma, stomach, bladder, esophagus, pancreas); 1 (liver, gallbladder, unidentified); 2 (others); 3 (kidney, uterus); 4 (rectum); and 5 (thyroid, breast, prostate, carcinoid tumor). A higher score is suggestive of better prognosis in this scoring system.

The predictive accuracy of Tokuhashi score has been reported in various studies to be 51%–88%.[16] Various authors have advocated the prognostic role of Tokuhashi score in patient survival after surgery for spinal metastasis[8],[9] while it has been questioned by other authors.[16],[17],[18] It may be better predictive in tumors with good survival but less useful in patients with expected survival less than one year and in certain tumor types like myeloma and lung carcinoma.[16]

Other authors have studied the role of Tomita Score, Karnofsky Performance Score and Eastern Cooperation Oncology Group (ECOG) Performance Score and found them to be reliable factors for predicting patient survival.[9],[11],[13],[19],[20]

Surgery type and patient survival

Lee et al.[18] in a retrospective study of 200 patients compared 3 different types of surgeries: en bloc surgery (total corpectomy + cage + posterior pedicle screws/anterior plate and screws); debulking surgery (Partial corpectomy+ cage/cement + pedicle screws or posterior laminectomy + removal of tumor mass± pedicle screws) and palliative surgery (laminectomy alone or pedicle screws alone or laminectomy + pedicle screws). The mean Tokuhashi score was higher in the en bloc group, than in the debulking group and palliative group (P = 0.001). Mean postoperative survivals were significantly better in the en bloc group than in debulking and palliative group.

Listed in [Table 1] are various studies that have reported on various prognostic factors affecting patient survival after surgery.
Table 1: Various studies reporting on prognostic factors affecting patient survival after surgery

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Neurological outcome and ambulatory capacity after surgery in Spinal metastatic Spinal cord compression

One of the most important consequences of metastatic involvement of the spine is MSCC, which can lead to neurological deficit and loss of ambulatory capacity hence metastatic cord compression is one of the major indications for surgery in patients presenting with spinal metastasis.

Effect of surgical timing in neurological recovery

Timing of surgery after the onset of neurological deficits following MSCC has been found to be major prognostic factor in neurological recovery in number of studies with better results in patients who were operated early.

In a retrospective analysis of 121 patients with neurological deficits, Quaraishi et al.[21] found significant difference between neurological recovery when surgery was done within 48 h and after 48 h. Likewise Frustenberg et al.[22] also reported that patients operated within 48 h had better recovery.

Hessler et al.[17] in their study reported neurological improvement in 78 patients (40.2%) of 194 operated patients with preoperative neurological deficit. In 31 patients there was complete remission of patient’s neurological symptoms. In their study they found that patients had better neurological recovery when operated within 3 days and recommended urgent surgery when deficit is less than 3 days.

Ambulatory capacity after surgery

Restoration of ambulation has major effect in quality of life after surgery in patients who have lost their ambulatory capacity as a result of MSCC. While it might not be possible to restore neurology to previous status in all instances, restoration of ambulatory capacity with or without support is considered an important surgical outcome.[23]

Surgical decompression was found to have restored ambulatory capacity in 52% to 77% of non-ambulatory patients in various studies.[4],[13],[24],[25] In 2005 meta-analysis by Klimo et al.[26] comparing the results of surgery with radiation therapy, out of 999 surgical patients, 384 were non ambulatory before surgery. Of these patients 228 (59.38%) regained capacity to ambulate after surgery in contrast to 79 of 265 patients (29.81%) in radiation therapy group.

Preoperative ambulatory status, preoperative motor grade and timing of surgery in patients who have deficits have been reported in different studies to affect postoperative ambulatory capacity in patients with spinal metastasis.[8],[10],[14],[24],[25],[27]

Chaichana et al.[25] studied the predictors of ambulatory function after surgery in 78 patients with spinal metastasis who had radiographic epidural cord compression. Of these 78 patients, 55 were ambulatory with or without support preoperatively whereas 23 were non-ambulatory. Following surgery 89% of the ambulatory patients maintained their ambulatory capacity whereas 12 of the 23 patients (52%) who were non-ambulatory preoperatively regained ambulatory capacity at the last follow-up. They reported that preoperative ability to walk and pathological compression fracture at the level of epidural compression (poor prognosis) were independent predictors of postoperative ambulatory capacity. In patients who were non-ambulatory prior to and regained ambulation after surgery, preoperative radiation therapy (poor prognosis), surgery within 48 h of symptoms and postoperative radiation therapy (good prognosis) were significant predictors of achieving ambulatory capacity.

Few authors have studied the effect of surgery type on neurological outcome. In a retrospective study of 84 patients by Cofano et al. with preoperative neurological deficits of which 18 were nonambulatory, 64% patients showed improvement in their neurological examination at discharge and 11 of 18 nonambulatory patients regained their ambulatory capacity.[28] The authors found that patients who had undergone anterior and circumferential decompression had better improvement in neurological outcome compared to posterior and posterolateral decompression. This can be explained by better decompression with anterior and circumferential approach compared to posterior approaches and also explains why laminectomy alone fared so poorly in the past.[1],[2] Similarly North et al.[14] also reported that patients with surgeries other than corpectomy had a poorer prognosis for postoperative ambulation.

Pain

Pain related to instability as a result of vertebral destruction due to the neoplastic process is also an important indication for surgery in patients with spinal metastasis. Various studies have reported on improvement of pain as a result of surgery in spinal metastasis.[4],[10],[14]

In the study by Chong et al.[10] there were 105 patients who underwent single stage posterior decompression and stabilization with or without corpectomy. The average preoperative VAS for pain was 6.5(±1.5) which reduced by an average of 3.2 (±1.8) at 2 weeks postoperatively. They reported that corpectomy and fixation levels >4 were significant factors that predicted postoperative relief of pain. Age, Karnofsky Performance Score, primary cancer type, time from diagnosis to metastasis, metastases to visceral organs, number of involved segments (single vs. multiple) and the axial extent (three column vs. two or less column) were not related to improvement of pain after surgery.

Complications

Numerous intraoperative and postoperative complications have been reported after surgery in patients with spinal metastasis. The 30-day mortality rate that quantifies the morbidity of these immediate and early postoperative complications was reported to be between 2.77% to 11% in different studies.[4],[7],[10],[11],[14],[25],[26]

Gokaslan et al.[4] reported 24 surgery related complications in 21 out of 72 operated patients. The complications that occurred were epidural hematoma and pneumonia in 3 patients each, GI bleed, CSF leak, renal failure, atrial fibrillation, pleural effusion and superficial wound infection in two each and cecal perforation and pulmonary embolism in one patient each. In 12 patients who underwent preoperative embolization, three patients had neurological worsening post procedure which led to permanent impairment in two patients.

Nonambulatory patients were reported to have a higher rate of complications in a study by Chaichana et al.[25] This is probably explained by higher number of levels of surgery and more number of laminectomies in this patient group compared with ambulatory patients due to more extensive nature of their disease. Reported complications in 78 patients were 4 wound dehiscence, 3 CSF leaks and 1 each of retroperitoneal hematoma and pseudomeningocele.

Timing of surgery did not have impact on complication rate in a study by Quarishi et al.[21] However more number of spinal metastasis were associated with more complications. Crnalic[11] reported 24 complications in 19 of 54 patients within 30 days of being operated for metastatic prostatic cancer with metastatic cord compression. Systemic complications like stroke, pulmonary embolism, pneumonia, septicemia, GI bleeding or intestinal rupture occurred in nine patients. Local complications like superficial wound infection, wound dehiscence, CSF leakage and sacral pressure sores were reported in eight patients. Two patients had both systemic and local complications.


  Patient Reported and Quality of Life Related Outcomes Top


Patient reported outcomes are now being recognized as valuable measures to determine the effectiveness of treatment and the impact on quality of life.[29] Feghali et al. suggested that measures of survival, pain, ambulation, neurological deficit and sphincter control were only indirect measurements of health status, which fail to capture the patient’s experience of the disease or HRQOL.[30]

There are number of tools that have been utilized to measure quality of life in patients with spinal metastasis like EQ-5D(European Quality of Life 5 Dimension Instrument, (Short Form) SF-36 Health Survey Questionnaire, Eastern Cooperation Oncology Group (ECOG), ODI and spine tumor specific outcome tools like Spine Oncologic Study Group Outcome Questionnaire (SOSGOQ) and Spine Tumor Module of M.D. Anderson Symptom Inventory (MDASI) of which validation studies have confirmed the usefulness of EQ-5D and SOSGOQ.[29],[30],[31]

It has been found that spine surgery can improve QOL in patients with spine metastasis.[30]

In a large multicentric study in 2015, Choi et al.[12] reported that preoperative QOL as measured by EQ-5D, Karnofsky Performance Score and Frankel Grade were significant factors that predicted the postoperative quality of life of patients who underwent surgery for spinal metastasis.

Barzilai et al.[32] reported that higher preoperative ASIA impairment Score (AIS) grade was predictive of better postoperative outcomes of several domains of SF-36 like walking 100 or several hundred yards, climbing one flight of stairs, bathing, dressing, lifting or carrying groceries. Preop AIS grade also impacted outcome parameters in SOSGOQ like leg weakness, walking assistance, activity level, spine related pain, working ability, ability to care for oneself, bowel and bladder control and conversations or reading or television.

Similarly in a retrospective of 151 patients with neurological deficits due to MSCC due to various primaries Lak et al.[33] reported that preoperative bowel and bladder dysfunction, motor weakness and higher American Society of Anesthesiologists (ASA) grade were related to poor functional outcome on ECOG Performance status (ECOG 0–2).


  Conclusions Top


Numerous factors like primary tumor type, oncological load of the disease like presence of visceral metastasis, number of spinal and extraspinal bony metastasis and patient score on various prognostic and functional scores like Tokuhashi, Tomita scores, Karnofsky Performance scale and ECOG performance status were found to impact patient survival after surgery for spinal metastasis. Among this the primary tumor type, number of spinal metastasis and neurological involvement are the major factors deciding the surgical outcome. Surgical management has been found to improve neurological function and restore ambulatory capacity in patients who have lost ambulation due to metastatic compression of spinal cord. As newer modalities of treatment like immunotherapy, targeted therapy and non-ionizing ablative therapy are evolving the outcomes for surgical management is likely to have a better future.

Ethical policy and institutional review board statement

Not applicable.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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Crnalic S, Hildingsson C, Wikström P, Bergh A, Löfvenberg R, Widmark A Outcome after surgery for metastatic spinal cord compression in 54 patients with prostate cancer. Acta Orthop 2012;83:80-6.  Back to cited text no. 11
    
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North RB, LaRocca VR, Schwartz J, North CA, Zahurak M, Davis RF, et al. Surgical management of spinal metastases: Analysis of prognostic factors during a 10-year experience. J Neurosurg Spine 2005;2:564-73.  Back to cited text no. 14
    
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