Spondylectomy for Giant Cell Tumor After Denosumab Therapy

Thoracic giant cell tumor after two total en bloc spondylectomies including one emergency surgery: A case report

BACKGROUND

For patients with acute paraplegia caused by spinal giant cell tumor (GCT) who require emergency decompressive surgery, there is still a lack of relevant reports on surgical options. This study is the first to present the case of an acute paraplegic patient with a thoracic spinal GCT who underwent an emergency total en bloc spondylectomy (TES). Despite tumor recurrence, three-level TES was repeated after denosumab therapy.

CASE SUMMARY

A 27-year-old female patient who underwent single-level TES in an emergency presented with sudden severe back pain and acute paraplegia due to a thoracic spinal tumor. After emergency TES, the patient's spinal cord function recovered, and permanent paralysis was avoided. The postoperative histopathological examination revealed that the excised neoplasm was a rare GCT. Unfortunately, the tumor recurred 9 months after the first surgery. After 12 months of denosumab therapy, the tumor size was reduced, and tumor calcification. To prevent recurrent tumor progression and provide a possible cure, a three-level TES was performed again. The patient returned to an active lifestyle 1 month after the second surgery, and no recurrence of GCT was found at the last follow-up.

CONCLUSION

This patient with acute paraplegia underwent TES twice, including once in an emergency, and achieved good therapeutic results. TES in emergency surgery is feasible and safe when conditions permit; however, it may increase the risk of tumor recurrence.

The efficacy and safety of short-course neoadjuvant denosumab for en bloc spondylectomy in spinal giant cell tumor of bone: a preliminary report

PURPOSE

This study aimed to investigate whether short course of neoadjuvant denosumab treatment for spinal GCTB could (1) Induce radiological and histological response? (2) Facilitate en bloc resection? (3) Achieve satisfactory oncological and functional outcomes?

METHODS

The clinical information of ten consecutive patients between 2018 and 2022 with spinal GCTB treated with short course of neoadjuvant denosumab (≤ 5 doses) and en bloc spondylectomy was retrospectively reviewed. The radiological and histological response, operative data, oncological and functional outcomes were analyzed.

RESULTS

The mean doses of neoadjuvant denosumab were 4.2 (range 3-5 doses). After neoadjuvant denosumab, there were 9 cases showing new ossification and 5 cases with reappearance of cortical integrity. The values of Hounsfield units (HU) of the soft tissue component were increased by > 50% in 7 cases. The signal intensity (SI) ratios of tumor/muscle in T2WI of plain MRI were decreased by > 10% in 60% of the cases. Shrinkage of soft tissue mass by > 10% was observed in 4 cases. The mean duration of operation was 575 ± 174 min, and the mean estimated blood loss (EBL) was 2790 ± 1934 ml. No obvious adhesion to dura mater or major vessels was encounter intraoperatively. There is no tumor collapse or breakage during surgery. Multinucleated giant cells were decreased in 6 cases (60%) with the remaining 4 cases showing absence of multinucleated giant cells. Mononuclear stromal cells existed in most of the cases (8 cases, 80%). New bone formation was noticed in 8 cases (80%). No patient had a worsening of neurologic function after surgery. No tumor recurrence was noticed within the mean follow-up of 24 ± 20 months.

CONCLUSION

Short-term neoadjuvant denosumab could yield radiological and histological responses and might facilitate en bloc spondylectomy by hardening the tumor and causing less adhesion to segmental vessels, major vessels and nerve roots, which was beneficial to achieve the optimal oncological and functional outcomes.

Comparison of the prognostic factors of total en bloc spondylectomy and total piecemeal spondylectomy in patients with Enneking stage III giant cell tumor in the thoracic and lumbar spine

PURPOSE

To compare total en bloc spondylectomy with marginal margins against piecemeal spondylectomy with intralesional margins in the surgical treatment of Enneking stage III spinal giant cell tumor (GCT) in terms of local recurrence.

METHODS

A retrospective survival analysis of patients with Enneking stage III GCT who underwent TES with marginal margins or total piecemeal spondylectomy with intralesional margins was performed between January 2006 and April 2020. Local recurrence-free survival (LRFS) was the time between the date of surgery and recurrence. Factors with p-values < 0.05 in the univariate analysis were included in the multivariate analysis using proportional hazard analysis.

RESULTS

Sixty patients (25 men and 35 women) with a mean age of 35.6 (range 11-71) years were included. The mean follow-up duration was 93 (range 24-198) months. Two patients were lost to follow-up 6 and 14 years after the procedure. Over a 10-year period, the recurrence rate was 13.3%. The 2-, 5-, and 10-year LRFS rates were 95%, 88%, and 78%, respectively. Univariate analysis identified total piecemeal spondylectomy and no adjuvant radiotherapy as prognostic factors for LRFS. Multivariate Cox-regression models showed a significant association between local recurrence and total piecemeal spondylectomy and no adjuvant radiotherapy.

CONCLUSION

TES with marginal margins is better than total piecemeal spondylectomy with intralesional margins owing to its lower postoperative recurrence rate. Adjuvant radiotherapy should be administered to reduce postoperative recurrence rates.

Diagnosis and Treatment of Lumbar Giant Cell Tumor of the Spine: Update on Current Management Strategies

(1) Background: Giant Cell Tumor of the spine remains a difficult tumor to treat. Recent advances in adjuvant therapy such as denosumab and innovations in surgical technique in the last 5 years have given providers new options for treatment after a successful diagnosis of the tumor. (2) Methods: Articles published between 1927 and 2021 were selected from PubMed and Scopus searches using key words “Giant Cell Tumor” AND “Lumbar Spine” AND “Treatment”. Relevant articles were reviewed and selected by the authors. (3) Results: A total of 191 articles were discovered. Complete en bloc spondylectomy remains the most definitive treatment option; however, this surgery is challenging and carries a high rate of complication. New adjuvant therapies including denosumab offer a viable alternative to surgery. (4) En bloc spondylectomy remains the gold standard treatment for Giant Cell Tumor of the spine with the lowest published recurrence rate. The use of (neo)adjuvant denosumab improves recurrence rates. More data are needed to determine if denosumab alone is a viable standalone definitive treatment.

Total en bloc spondylectomy is worth doing in complete paralysis spinal giant cell tumor, a minimum 1-year follow-up

OBJECTIVE

To investigate the neurological recovery of Frankel A spinal giant cell tumor (GCT) patients after they had received a Total En Bloc Spondylectomy (TES).

MATERIALS AND METHODS

We retrospectively recorded data of three patients (two females) with mobile spine GCT (T6, T10, and L2) Enneking stage III with complete paralysis before surgery, who had undergone TES in our institute from January 2018 to September 2020. The duration of neurologic recovery to Frankel E was the primary outcome. The intra-operative blood loss, operative time, operative-related complications, and the local recurrence were the secondary outcomes.

RESULTS

The duration of suffering from Frankel A to TES surgery was 2 months for the T6 patient, 3 weeks for the T10 patient, and 1 month for the L2 patient. Three patients had achieved full neurological recovery to Frankel E within 6 months after TES (T6 for 5 months, T10 for 3 months, and L2 for 3 months). The average blood loss was 2833.33 ml and the mean operative time was 400 min. Up until the last follow-up (13-25 months), no evidence of local recurrences had been found in any of the three patients.

CONCLUSION

Frankel A spinal GCT patients can achieve full neurological recovery after TES, if the procedure is performed within 3 months after complete paraplegia. TES can effectively control any local recurrences.

Spondylectomy in the treatment of neoplastic spinal lesions - A retrospective outcome analysis of 582 patients using a patient-level meta-analysis

This study aims at identifying predictors of postoperative complications, lesion recurrence, and overall survival in patients undergoing en bloc spondylectomy (EBS) for spinal tumors. For this purpose a systematic review of the literature was conducted and patient-level data extracted. Linear-regression models were calculated to predict postoperative complications, lesion recurrence and overall survival based on age, tumor etiology, surgical approach, mode of resection (extra- vs. intralesional), tumor extension, and number of levels treated. A total of 582 patients were identified from the literature: 45% of females, median age 46 years (5-78); most common etiologies were: sarcoma (46%), metastases (31%), chordoma (11%); surgical approach was anterior (2.5%), combined (45%), and posterior (52.4%); 68.5% underwent EBS; average levels resected were 1.6 (1-6); average survival was 2.6 years; Complication rate was 17.7%. The following significant correlations were found: postoperative complications and resection mode (Odds ratio [OR] 1.35) as well as number of levels treated (OR 1.35); tumor recurrence and resection mode (OR 0.78); 5-year survival and age (OR 0.79), tumor grade (OR 0.65), tumor stage at diagnosis (OR 0.79), and resection mode (OR 1.68). EBS was shown to improve survival, decreases recurrence rates but also has a higher complication rate. Interestingly, the complication rate was not influenced by tumor extension or tumor etiology.

Giant Cell Tumor of Bone of the First Rib Successfully Treated with Combined Preoperative Denosumab Therapy and Surgery via a Transmanubrial Approach

Patient: Female, 27-year-old

Final Diagnosis: Giant cell tumor of bone

Symptoms: No symptom

Medication:—

Clinical Procedure: —

Specialty: Oncology

Denosumab for Effective Tumor Size Reduction in Patients With Giant Cell Tumors of the Bone: A Systematic Review and Meta-Analysis

BACKGROUND

Denosumab is a human monoclonal antibody that has been used successfully in the treatment of giant cell tumors of bone. These tumors are rare and, in principle, benign, but they are highly aggressive, locally advanced, osteolytic bone tumors that can metastasize to the lungs. Denosumab is an effective treatment when these tumors cannot be surgically removed or when surgical resection is likely to lead to severe morbidity (eg, loss of limbs or joints). The aim of this systematic review and meta-analysis was to investigate patients with giant cell tumors of bone who experienced tumor progression during treatment with denosumab and to compare them with patients who experienced reduction of their giant cell tumors of bone during treatment with denosumab.

METHODS

Embase, Cochrane Library, and MEDLINE/PubMed databases were searched for trials submitted by January 7, 2020, that reported the efficacy and safety of denosumab in patients with giant cell tumors of bone.

RESULTS

Sixty studies were reviewed, involving a total of 1074 patients who had giant cell tumors of bone and were treated with denosumab. Of the 60 studies, 58% of the patients were from case series studies, 39% from open-label phase II studies, and 3% from case reports. The response rate for denosumab as a treatment for giant cell tumors of bone was 97.5%, with statistical significance (P < .0001). Pain in the limbs was statistically the most common adverse event for denosumab treatment in case series studies (P < .0001). No treatment-related deaths occurred in the reviewed studies.

CONCLUSION

Cumulative evidence supports the addition of surgery to optimal medical therapy with denosumab to reduce tumor size, clinical symptoms, and mortality among patients with giant cell tumors of bone.

Overview of the management of primary tumors of the spine

STUDY DESIGN

Narrative review.

OBJECTIVE

To provide a narrative review for diagnosis and management of Primary spine tumors.

METHODS

A detailed review of literature was done to identify relevant and well cited manuscripts to construct this narrative review.

RESULTS

Primary tumors of the spine are rare with some racial differences reported. There are numerous adjuvant technologies and developments that influence the way we currently manage these tumors. Collimated radiation allows for heavy dosage to be delivered and have been reported to give good local control both as an adjuvant and neoadjuvant setting. These have made surgical decision making even more intricate needing a multicentric approach. Dedicated care has been shown to significantly improve health quality of life measures and survival.

CONCLUSION

While, it is beyond the scope of this paper to discuss all primary tumors subtypes individually, this review highlights the developments and approach to primary spine tumors.

Recurrent giant cell tumour of the thoracic spine managed by total en bloc spondylectomy and denosumab therapy: a case report

Background

Giant cell tumour (GCT) of the bone is a rare, invasive benign bone tumour, which typically originates in the metaphyseal ends of long bones and rarely in the spine. Here, we report a rare case of recurrent GCT of the thoracic vertebra, which was managed by three-level total en bloc spondylectomy (TES) after denosumab therapy.

Case presentation

A 50-year-old woman presented with a 2-month history of progressive lower back pain. Magnetic resonance imaging revealed destruction of the T11 vertebra and a soft tissue mass. The patient underwent tumour resection. Computed tomography at the 2-year follow-up revealed relapse of the resected tumour, which had spread to the T12 vertebral body. Subsequently, denosumab therapy was administered to the patient for 1 year. The growth of the tumour was controlled, and its boundary line was clear. Thereafter, TES for the T10-T12 vertebrae was performed, and spinal reconstruction was completed through a one-stage single posterior approach. The patient’s condition improved postoperatively, and no evidence of recurrence of GCT of the bone or spinal deformity was observed at the 32-month follow-up.

Conclusions

Denosumab therapy contributed to tumour regression. Three-level TES may be an effective and feasible strategy for managing large recurrent GCTs of the spine after denosumab therapy.

Denosumab in the treatment of giant cell tumor of the spine. Preliminary report, review of the literature and protocol proposal

BACKGROUND

The interest on the role of Denosumab in the treatment strategy of giant cell tumor of the spine is growing. En bloc resection is considered the Enneking appropriate treatment, but morbidity and functional loss are sometimes unacceptable. Denosumab could play a role as a stand-alone treatment, but also as preoperative treatment or as postoperative after intralesional surgery.

MATERIALS AND METHODS

A cohort of 10 out of 12 cases of spinal GCT consecutively treated with Denosumab are analyzed and discussed compared to the cases reported in the literature. A staging of the radiological effect of the treatment is proposed.

RESULTS

The stand-alone and postoperative treatments are still running (12 to 88 months). One therapy was stopped after 15 months, once a satisfactory local effect was achieved, but the treatment had to be restarted 2 months later due to the recurrence of the erosive images. The new treatment was successful. At 1-year follow-up after the gross total excision followed by postoperative Denosumab treatment, no evidence of local recurrence was found. The preoperative treatment duration ranged from 3 to 24 months. No local recurrence followed the en bloc resections.

CONCLUSIONS

Denosumab alone is effective in relieving pain, increasing the ossification and sometimes reducing the tumor volume. It can be considered an excellent solution in spine GCTs whose surgical treatment cannot be Enneking appropriate or is associated with unacceptable morbidity or loss of functions. It is still impossible to state when to safely stop the treatment. Denosumab also plays a role as preoperative protocol. These slides can be retrieved under Electronic Supplementary Material.

Short-term Preoperative Denosumab With Surgery in Unresectable or Recurrent Giant Cell Tumor of Bone

Objective

The purpose of this retrospective study was to evaluate the clinical and oncological results of combination treatment of short‐term preoperative denosumab (the receptor activator of nuclear factor kappa‐B ligand inhibitor) with surgery in unresectable or recurrent cases of giant cell tumor of the bone (GCTB).

Methods

Between 2016 and 2018, 11 eligible patients (1 man, 10 women, mean age 38.1 years) with grade 3 GCTB were treated with a combination of short‐term (six doses) preoperative denosumab and surgery in a single institution. The clinical, radiological, and pathological alteration after the denosumab treatment were compared. The oncological results of the combination therapy were also recorded. Meanwhile, adverse effects or complications of denosumab, if any, were reported.

Results

The median follow‐up time after surgical procedure was 30 months (range 13–45 months). After 3–4 denosumab injections, pain relief was observed in all patients. In two spine patients, the neurological status improved after four doses of treatment. Intraoperatively, the margin of the tumor became clear and the intensity of the tumor increased while the blood supply around and within the lesion decreased. Within the lesion, the typically soft and loose tissue were replaced by the tough and dense fibro‐osseous tissue. The mean diameter of the lesion before and after treatment was 61.55 ± 22.49 mm and 51.81 ± 21.12 mm, respectively, and the T‐score was 1.02 (P = 0.32). Variable calcification was observed at the periphery and within the lesion. A total of three patients experienced local recurrence in this study. In the resection group, only one extremity patient had soft tissue recurrence that was treated with en‐bloc excision. In the curettage group, two of three sacral tumor patients had local occurrence. Both refused re‐operation and restarted the monthly denosumab injection thereafter, and the lesions remained stable at the final follow up. Finally, no adverse effects or complications related to denosumab treatment were found.

Conclusion

For the unresectable or recurrent GCTB cases, short‐term (six doses) preoperative use of denosumab improved clinical symptoms, decreased the tumor size, and increased the tumor density. The changes in tumors, in turn, simplified the tumor removal manipulation and, subsequently, decreased the local recurrence for the resection surgery. For the curettage, the denosumab‐induced changes had mixed impacts, and shorter term (fewer than six doses) usage may be more appropriate. Our six‐dose regime was deemed safe, while the safety of long‐term use remains unknown.

Giant cell tumor of the eleventh thoracic vertebra in a pediatric patient: an interesting case report and comprehensive literature review

INTRODUCTION

Giant cell tumors of the mobile spinal column are very rare tumors, especially in the pediatric age group. Although they are benign tumors, they have locally aggressive growth pattern and high risk of recurrence.

CASE PRESENTATION

We report a 15-year-old female patient with thoracic giant cell tumor who underwent percutaneous vertebroplasty and had cement extravasation into the spinal canal. Because of the deterioration of the patient's neurological condition, total enbloc spondylectomy and cement excision were performed. She underwent instrumentation and fusion procedures in order to prevent spinal instability.

CONCLUSION

The main purpose of the treatment is gross total resection of the giant cell tumor. However, adjuvant methods such as denosumab should be added to the treatment protocol in patients who are older than 2 years old and can not undergo gross total resection due to tumor size and anatomic localization.

Recurrence of Giant Cell Tumor of the Spine after Resection: A Report of 10 Cases

Objective

To review the clinical details and further treatments for recurrent spinal giant cell tumors (SGCT), and to analyze the risk factors of recurrence and shed new light on the treatment options and prognosis of recurrent SGCT.

Methods

A retrospective analysis of recurrent SGCT between April 2003 and January 2014 was performed. A total of 10 patients comprising 3 men and 7 women with a mean age of 28.9 years (range, 21–40 years) were included in the study. All complete clinical data, radiographs, CT, MRI, scans and pathological data were reviewed. The tumor locations and the regions involved were evaluated by CT and MRI. The blood supply of the tumors was evaluated by enhanced CT and MRI. The mean follow‐up was 81.3 months (range, 35.7–172.1 months).

Results

All patients had Enneking stage 3 tumors; 9 (90%) of them had different extents of spinal canal involvement in the primary time period. All patients underwent intralesional resection during their first surgery. Only 1 patient received local adjuvant treatments; no patient underwent selective arterial embolization or used denosumab at that time. Only 1 patient underwent adjuvant radiotherapy postoperatively, and another patient used bisphosphonates. After recurrence, 1 patient was cured using denosumab, and 2 patients' disease was controlled through use of other medical treatments or adjuvant treatments. There were 3 repeated recurrences and 7 repeated surgical procedures were performed in 5 patients. There were 6 intralesional excisions and 1 decompression surgery. The mean relapse‐free time after the first surgery was 32.3 months (range, 10.5–62.6 months). The overall mean relapse‐free time was 40.2 months (range, 10.5–157 months). No distant metastasis was found in our series. At the final follow‐up, 4 patients were disease free, 3 patients' disease was under control, 2 has progressive disease aggravation, while 1 patient died as a result of progression of disease 133.9 months after first surgery.

Conclusion

Intralesional excision for recurrent spinal giant cell tumors is an effective option that may have satisfactory prognosis. However, the excision and the inactivation of the lesion should be carried out carefully and thoroughly without missing any corners. Early diagnosis of recurrence may be associated with better prognosis. Adjuvant treatments perioperatively and systemic medical treatments can decrease recurrence rates and can have therapeutic effects in the recurrent SGCT.

Denosumab May Increase the Risk of Local Recurrence in Patients with Giant-Cell Tumor of Bone Treated with Curettage

BACKGROUND

Recent clinical studies have suggested that denosumab is associated with tumor response and reduced surgical morbidity in patients with giant-cell tumor of bone (GCTB). We therefore evaluated the recurrence-free survival rate of patients who had GCTB in an extremity and were treated with surgery and denosumab, to determine the influence of denosumab and clinical factors on the risk of local recurrence.

METHODS

We retrospectively reviewed the medical records of 408 patients treated for GCTB in an extremity in a single institution from 1990 through 2013. Two hundred and forty-seven patients underwent curettage (intralesional surgery) with a high-speed burr, and 161 underwent resection. Phenol adjuvant was used in 221 of the 247 patients who had curettage. We also reviewed the medical records of 30 patients treated surgically (25 with curettage and 5 with resection) and with denosumab from 2010 through 2013 and compared their clinical results with 378 historical control subjects. The overall minimum duration of follow-up was 24 months.

RESULTS

The local recurrence rates were 60% (15) of 25 patients treated with curettage and denosumab and 16% (36) of 222 patients treated with curettage alone. The joint preservation rates were 80% (20) of 25 patients treated with curettage and denosumab and 94% (209) of 222 patients treated with curettage alone. Univariate and multivariable analyses showed that denosumab was the only independent factor associated with a poor prognosis when recurrence-free survival and joint preservation were considered. The overall median duration of follow-up was 85.6 months (interquartile range, 54.3 to 125.1 months). Viable tumor was present in all 30 specimens from patients treated with denosumab.

CONCLUSIONS

There was a higher rate of recurrence in the cohort exposed to denosumab. Because there were substantial differences in the cohorts and randomization was not applied, however, causation could not be evaluated.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Total en bloc spondylectomy of the eleventh thoracic vertebra following denosumab therapy for the treatment of a giant cell tumor

Although denosumab has been reported to induce effective clinical results with respect to tumor shrinkage in a short-term follow-up clinical study, total spondylectomy is recognized as the treatment of choice for eradicating giant cell tumors (GCTs) of the spine. The present study reports the case involving a GCT in the 11th thoracic vertebra complicated by idiopathic scoliosis and treated using total en bloc spondylectomy (TES) with preoperative denosumab therapy. A 35-year-old woman received preoperative denosumab therapy for 8 months, followed by surgery using a computed tomography (CT)-based navigation system that optimized accuracy by recognizing the area of the detached parietal pleura, the irregular border of the collapsed vertebra, and the adjacent vertebra. Complete en bloc resection of the vertebra could be performed, suggesting denosumab can be an effective adjuvant therapy which can reduce the complexity of TES and CT-navigation system facilitated the safe use of this surgical method in a patient with idiopathic scoliosis.

How safe and effective is denosumab for bone giant cell tumour?

Recent clinical studies have suggested that denosumab is associated with beneficial tumour response, surgical down-staging, and reduced surgical morbidity in patients with giant cell tumour of bone. However, these studies reported results of patients still on denosumab treatment, or patients after denosumab treatment but with a short follow-up. Other studies reported that the new osseous tumour matrix and thickened cortical bone that develop with denosumab treatment does not allow the surgeon to delineate the true extent of the tumour, and probably increases the risk for local recurrence. A study showed that cell proliferation is only diminished by denosumab; the cells continue to proliferate in vitro, albeit at a slower rate. More importantly, nine cases of malignant transformation of GCT during denosumab therapy without previous radiation exposure have been reported; inhibition of RANKL may increase the risk of new malignancies due to immunosuppression. With these concerns in mind, this article is an attempt to put essential information in one place, creating a comprehensive review that the curious reader would find interesting and informative.

Giant cell tumor of the thoracic spine completely removed by total spondylectomy after neoadjuvant denosumab therapy

PURPOSE

Denosumab, a novel monoclonal antibody that targets the receptor activator of nuclear factor-κB (RANK) ligand (RANKL), has recently been used to treat patients with giant cell tumor of bone (GCTB). However, few reports have described the clinical results of denosumab therapy for spinal GCTB and evaluated treatment efficacy with respect to the entirety of the resected vertebra after denosumab therapy.

METHODS

We present the case of a 51-year-old man with T12 GCTB that was completely removed by a total spondylectomy following 10 courses of neoadjuvant denosumab therapy. Post-therapy radiological findings indicated epidural tumor reduction in the spinal canal and sclerotic rim formation. However, the affected vertebra collapsed despite denosumab therapy and a massive bridging callus formation was present between the spinal GCTB and adjacent vertebra.

RESULTS

These morphological changes made the tumor margins unclear and increased the difficulty of dissection of the segmental arteries from the vertebral body and en bloc corpectomy by a posterior-approach. Pathological findings indicated increased woven bone at the peripheral lesion of the resected vertebra and RANKL-positive stromal cells remained around the woven bone.

CONCLUSIONS

These findings support that GCTB stromal cells survived around the newly formed woven bone after long-term denosumab treatment and total surgical resection of such primary spinal lesions as the gold-standard treatment, even following administration of denosumab. Surgeons should note that prolonged adjuvant denosumab therapy may increase the difficulty of performing a posterior-approach total en bloc spondylectomy.

Bone graft options for spinal fusion following resection of spinal column tumors: systematic review and meta-analysis

OBJECTIVE With the advent of new adjunctive therapy, the overall survival of patients harboring spinal column tumors has improved. However, there is limited knowledge regarding the optimal bone graft options following resection of spinal column tumors, due to their relative rarity and because fusion outcomes in this cohort are affected by various factors, such as radiation therapy (RT) and chemotherapy. Furthermore, bone graft options are often limited following tumor resection because the use of local bone grafts and bone morphogenetic proteins (BMPs) are usually avoided in light of microscopic infiltration of tumors into local bone and potential carcinogenicity of BMP. The objective of this study was to review and meta-analyze the relevant clinical literature to provide further clinical insight regarding bone graft options. METHODS A web-based MEDLINE search was conducted in accordance with preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines, which yielded 27 articles with 383 patients. Information on baseline characteristics, tumor histology, adjunctive treatments, reconstruction methods, bone graft options, fusion rates, and time to fusion were collected. Pooled fusion rates (PFRs) and I² values were calculated in meta-analysis. Meta-regression analyses were also performed if each variable appeared to affect fusion outcomes. Furthermore, data on 272 individual patients were available, which were additionally reviewed and statistically analyzed. RESULTS Overall, fusion rates varied widely from 36.0% to 100.0% due to both inter- and intrastudy heterogeneity, with a PFR of 85.7% (I² = 36.4). The studies in which cages were filled with morselized iliac crest autogenic bone graft (ICABG) and/or other bone graft options were used for anterior fusion showed a significantly higher PFR of 92.8, compared with the other studies (83.3%, p = 0.04). In per-patient analysis, anterior plus posterior fusion resulted in a higher fusion rate than anterior fusion only (98.8% vs 86.4%, p < 0.001). Although unmodifiable, RT (90.3% vs 98.6%, p = 0.03) and lumbosacral tumors (74.6% vs 97.9%, p < 0.001) were associated with lower fusion rates in univariate analysis. The mean time to fusion was 5.4 ± 1.4 months (range 3-9 months), whereas 16 of 272 patients died before the confirmation of solid fusion with a mean survival of 3.1 ± 2.1 months (range 0.5-6 months). The average time to fusion of patients who received RT and chemotherapy were significantly longer than those who did not receive these adjunctive treatments (RT: 6.1 months vs 4.3 months, p < 0.001; chemotherapy: 6.0 months vs 4.3 months, p = 0.02). CONCLUSIONS Due to inter- and intrastudy heterogeneity in patient, disease, fusion criteria, and treatment characteristics, the optimal surgical techniques and factors predictive of fusion remain unclear. Clearly, future prospective, randomized studies will be necessary to better understand the issues surrounding bone graft selection following resection of spinal column tumors.

Benign Tumors of the Spine: Has New Chemotherapy and Interventional Radiology Changed the Treatment Paradigm?

STUDY DESIGN

Clinically based systematic review.

OBJECTIVE

To determine the role of (A) medical treatment and (B) interventional radiology as either adjuvant or stand-alone treatment in primary benign bone tumors of the spine.

METHODS

A multidisciplinary panel of spine surgeons, radiation oncologists, and medical oncologists elaborated specific focused questions regarding aneurysmal bone cyst, giant cell tumor, and osteoid osteoma. Denosumab, bisphosphonate, interferon, bone marrow aspirate, doxycycline, thermal ablation, and selective arterial embolization were identified as areas of interest for the article. A systematic review was performed through MEDLINE and EMBASE. Recommendations based on the literature review and clinical expertise were issued using the GRADE system.

RESULTS

The overall quality of the literature is very low with few multicenter prospective studies. For giant cell tumor, combination with Denosumab identified 14 pertinent articles with four multicenter prospective studies. Nine studies were found on bisphosphonates and six for selective arterial embolization. The search on aneurysmal bone cyst and selective arterial embolization revealed 12 articles. Combination with Denosumab, Doxycycline, and bone marrow aspirate identified four, two, and three relevant articles respectively. Eleven focused articles were selected on the role of thermal ablation in osteoid osteoma.

CONCLUSION

Alternative and adjuvant therapy for primary benign bone tumors have emerged. Their ability to complement or replace surgery is now being scrutinized and they may impact significantly the algorithm of treatment of these tumors. Most of the data are still emerging and further research is desirable. Close collaboration between the different specialists managing these pathologies is crucial.

LEVEL OF EVIDENCE

N/A.

Denosumab for Treatment of a Recurrent Cervical Giant-Cell Tumor

A 43-year-old male patient with C5 giant cell tumor (GCT) underwent tumor resection and anterior bone fusion of C4–C6. The tumor recurred locally 9 months after surgery with the patient complaining of neck and shoulder pain similar to his preoperative symptoms. Denosumab was administered and his pain disappeared after a two-month administration, with a sclerotic rim formation seen at the tumor site on computed tomography. He has been followed for 18 months with no evidence of tumor recurrence. Complete resection is generally recommended, but is not easy for many patients with cervical GCT because of the existence of neurovascular structures. Some patients suffer from recurrence and treatment becomes more difficult. As such, denosumab may be an efficacious option for treatment of recurrent GCT of the cervical spine, although long-term follow-up is required to monitor for presence or absence of recurrence.

Remarkable regression of a giant cell tumor of the cervical spine treated conservatively with denosumab: A case report

INTRODUCTION

Wide resection of giant cell tumors at the cervical spine is sometimes extremely challenging, especially in cases where tumors extend into the nearby tissues, such as vertebral arteries, the spinal cord, or spinal nerve roots. Denosumab, a human monoclonal antibody that binds the receptor activator of nuclear factor κ-β ligand, is reported to be effective for decreasing resorption of giant cell tumor of the bone, but the detailed progress of giant cell tumors in the cervical spine extending into the nearby tissues after such treatment has not been reported.

PRESENTATION OF CASE

A 41-year-old man presented with neck pain. Computed tomography-guided needle biopsy showed numerous giant cells with a large vesicular nucleus, consistent with a giant cell tumor. Because of the extension of the tumor with involvement of the vertebral artery and surrounding tissues, denosumab (120mg) was administered subcutaneously once per month for 24 months. Six months after denosumab treatment, follow-up computed tomography revealed a dramatic regression and osteosclerosis of the tumor. Two years after starting denosumab treatment, positron emission tomography showed no tumor recurrence.

DISCUSSION

Although the tumor was extended with involvement of the surrounding tissues and surgery following denosumab treatment was not performed, at 24 months since initiation of denosumab treatment we confirmed complete regression radiographically.

CONCLUSIONS

Denosumab may be used as an adjuvant by which to avoid or reduce the risks and morbidity of surgical treatment in patients with spinal giant cell tumors extending into nearby tissues.