Feasibility study on the clinical application of CT-based synthetic brain T1-weighted MRI: comparison with conventional T1-weighted MRI.

OBJECTIVES: This study aimed to examine the equivalence of computed tomography (CT)-based synthetic T1-weighted imaging (T1WI) to conventional T1WI for the quantitative assessment of brain morphology. MATERIALS AND METHODS: This prospective study examined 35 adult patients undergoing brain magnetic resonance imaging (MRI) and CT scans. An image synthesis method based on a deep learning model was used to generate synthetic T1WI (sT1WI) from CT data. Two senior radiologists used sT1WI and conventional T1WI on separate occasions to independently measure clinically relevant brain morphological parameters. The reliability and consistency between conventional and synthetic T1WI were assessed using statistical consistency checks, comprising intra-reader, inter-reader, and inter-method agreement. RESULTS: The intra-reader, inter-reader, and inter-method reliability and variability mostly exhibited the desired performance, except for several poor agreements due to measurement differences between the radiologists. All the measurements of sT1WI were equivalent to that of T1WI at 5% equivalent intervals. CONCLUSION: This study demonstrated the equivalence of CT-based sT1WI to conventional T1WI for quantitatively assessing brain morphology, thereby providing more information on imaging diagnosis with a single CT scan. CLINICAL RELEVANCE STATEMENT: Real-time synthesis of MR images from CT scans reduces the time required to acquire MR signals, improving the efficiency of the treatment planning system and providing benefits in the clinical diagnosis of patients with contraindications such as presence of metal implants or claustrophobia. KEY POINTS: • Deep learning-based image synthesis methods generate synthetic T1-weighted imaging from CT scans. • The equivalence of synthetic T1-weighted imaging and conventional MRI for quantitative brain assessment was investigated. • Synthetic T1-weighted imaging can provide more information per scan and be used in preoperative diagnosis and radiotherapy.

Complications and prognosis of primary thoracic and lumbar giant cell tumors treated by total tumor resection.

BACKGROUND: Spinal giant cell tumor (SGCT) is a relatively rare primary tumor. En bloc resection is the preferred surgical procedure for it due to its aggressiveness, meanwhile leading to more complications. We reported the characteristics of perioperative complications and local control of total tumor resection including en bloc resection and piecemeal resection for primary thoracic and lumbar spinal giant cell tumors in a single center over 10 years. METHODS: This is a retrospective cross-sectional and cohort study. Forty-one consecutive patients with SGCTs who underwent total tumor resection from 2010 to 2020 at our institution and were followed up for at least 24 months were reviewed. Surgery data, complication characteristics and local tumor control were collected and compared by different surgical procedure. RESULTS: Forty-one patients were included, consisting of 18 males and 23 females, with a mean age of 34.2 years. Thirty-one had thoracic vertebra lesions, and 10 had lumbar vertebra lesions. Thirty-five patients were primary cases, and 6 patients were recurrent cases. Eighteen patients were treated by total en bloc spondylectomy (TES), 12 patients underwent en bloc resection according to WBB surgical system, and 11 patients underwent piecemeal resection. The average surgical time was 498 min, and the mean estimated blood loss was 2145 ml. A total of 58 complications were recorded, and 30 patients (73.2%) had at least one perioperative complication. All patients were followed up after surgery for at least 2 years. A total of 6 cases had postoperative internal fixation failure, and 4 cases presented local tumor recurrence (9.8%). CONCLUSIONS: Although the surgical technique is difficult and accompanied by a high rate of perioperative complications, en bloc resection can achieve favorable local control in SGCT. When it is too difficult to complete en bloc resection, thoroughly piecemeal resection without residual is also acceptable, given the relatively low recurrence rate.

The automatic evaluation of steno-occlusive changes in time-of-flight magnetic resonance angiography of moyamoya patients using a 3D coordinate attention residual network.

Background: Moyamoya disease (MMD) is a rare cerebrovascular occlusive disease with progressive stenosis of the terminal portion of internal cerebral artery (ICA) and its main branches, which can cause complications, such as high risks of disability and increased mortality. Accurate and timely diagnosis may be difficult for physicians who are unfamiliar to MMD. Therefore, this study aims to achieve a preoperative deep-learning-based evaluation of MMD by detecting steno-occlusive changes in the middle cerebral artery or distal ICA areas. Methods: A fine-tuned deep learning model was developed using a three-dimensional (3D) coordinate attention residual network (3D CA-ResNet). This study enrolled 50 preoperative patients with MMD and 50 controls, and the corresponding time of flight magnetic resonance angiography (TOF-MRA) imaging data were acquired. The 3D CA-ResNet was trained based on sub-volumes and tested using patch-based and subject-based methods. The performance of the 3D CA-ResNet, as evaluated by the area under the curve (AUC) of receiving-operator characteristic, was compared with that of three other conventional 3D networks. Results: With the resulting network, the patch-based test achieved an AUC value of 0.94 for the 3D CA-ResNet in 480 patches from 10 test patients and 10 test controls, which is significantly higher than the results of the others. The 3D CA-ResNet correctly classified the MMD patients and normal healthy controls, and the vascular lesion distribution in subjects with the disease was investigated by generating a stenosis probability map and 3D vascular structure segmentation. Conclusions: The results demonstrated the reliability of the proposed 3D CA-ResNet in detecting stenotic areas on TOF-MRA imaging, and it outperformed three other models in identifying vascular steno-occlusive changes in patients with MMD.

Risk Factors and Three Radiological Predictor Models for the Progression of Proximal Junctional Kyphosis in Adult Degenerative Scoliosis Following Posterior Corrective Surgery: 113 Cases With 2-years Minimum Follow-Up.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To identify risk factors and predictive models for proximal junctional kyphosis (PJK) in a long-term follow-up of patients with adult degenerative scoliosis (ADS) following posterior corrective surgeries. MATERIALS AND METHODS: A consecutive 113 ADS patients undergoing posterior corrective surgery between January 2008 and April 2019 with minimum 2-year follow-up were included. All patients underwent preoperative, postoperative, and final follow-up by X-ray imaging. Multivariate logistic analysis was performed on various risk factors and radiological predictor models. RESULTS: PJK was identified radiographically in 46.9% of patients. Potential risk factors for PJK included postoperative thoracic kyphosis (TK) (P < .05), final follow-up Pelvic Tilt (PT) (P < .05), PT changes at final follow-up (P < .05), age over 55 years old at the surgery (P < .05), theoretical thoracic kyphosis-actual thoracic kyphosis mismatch (TK mismatch) (P < .05) and theoretical lumbar lordosis-acutal lumbar lordosis mismatch (LL mismatch) (P < .05). As for the predictive models, PJK was predictive by the following indicators: preoperative global sagittal alignment ≥45° (Model 1), postoperative pelvic incidence-lumbar lordosis mismatch (PI-LL)≤10° and postoperative PI-LL overcorrection (Model 2), and TK+LL≥0° (Model 3) (P < .05). Postoperative TK mismatch (OR = 1.064) was independent as risk factors for PJK, with the cut-off values respectively set at -28.56° to predict occurrence of PJK. CONCLUSION: The risk of radiographic PJK increases with an age over 55 years old and higher postoperative TK. In addition, postoperative TK mismatch is an independent risk factor for developing PJK. All three predictive models could effectively indicate the occurrence of PJK.

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.

Medium to long term follow-up of survival and quality of life in patients with primary tumors of the cervical spine: Experience From a large single center.

Objectives: To evaluate the survival and medium to long term health-related quality of life (HRQoL) of patients with primary cervical spinal tumors in a cross-sectional study and to identify any significant associations with demographic or clinical characteristics. Methods: Patients diagnosed with primary cervical spinal tumors were retrospectively enrolled and their clinical, radiologic, and follow-up data (specifically the EQ-5D questionnaire) were collected. Univariate and multivariate Cox time-dependent regression analyses were performed to examine the significance of certain variables on overall survival. Univariate and multivariate logistic regression analyses were conducted to identify variables significant for overall HRQoL and each dimension of the EQ-5D. Results: A total of 341 patients were enrolled in the study with a mean follow-up of 70 months. The diagnosis was benign in 246 cases, malignant in 84, and unconfirmed in 11. The 5-year overall survival rate was 86% and the 10-year overall survival rate was 65%. Multivariate analysis suggested that surgical treatment (P = 0.002, hazard ratio [HR] = 0.431, 95% CI. [0.254, 0.729]), benign and malignant tumors [P < 0.001, HR = 2.788, 95% CI. (1.721, 4.516)], tumor and surrounding normal tissue boundary [P = 0.010, HR = 1.950, 95% CI. (1.171, 3.249)], and spinal instability [P = 0.031, HR = 1.731, 95% CI. (1.051, 2.851)] still had significant effects on survival. Conclusions: In this cross-sectional study, we evaluated the survival period and medium and long-term health-related quality of life of patients with primary tumors of the cervical spine, and analyzed the significant related factors of tumor clinical characteristics. Surgery, myelopathy, malignancy, spinal pain relieved by lying down or supine position, and tumor infiltration on MRI were significant predictors for overall survival. Enneking stage and age were significant predictors for HRQoL.

A prospective randomized cohort study on 3D-printed artificial vertebral body in single-level anterior cervical corpectomy for cervical spondylotic myelopathy.

BACKGROUND: This was a prospective randomized cohort study aiming at examining the safety and efficacy of artificial vertebral body (AVB) fabricated by electron beam melting (EBM) in comparison to conventional titanium mesh cage (TMC) used in single-level anterior cervical corpectomy and fusion (SL-ACCF). METHODS: Forty patients with cervical spondylotic myelopathy (CSM) underwent SL-ACCF using either the EBM-AVB or the TMC. Patients were evaluated for their demographics, radiological characteristics, neurologic function [using the Japanese Orthopaedic Association (JOA) scale], and health-related quality-of-life (HRQoL) aspects [using the Short Form 36 (SF-36)] before and after the surgery and comparison was made between the two groups both at baseline and the last follow-up. The Student t-text, paired-sample t-text, and Fisher's exact test were used when appropriate to detect any statistical significance at the level of α=0.05. RESULTS: Post-operative recovery was uneventful for all patients and no revision surgery was required. There were no significant differences between the EBM-AVB group and the TMC group at baseline. Patients in both groups demonstrated significant improvement in cervical alignment, JOA score, and SF-36 score after the surgery. Six months post-operatively, patients in the EBM-AVB group were found to have significantly less loss of fusion height and lower incidence for severe implant subsidence compared with the TMC group. Patients in the two groups were comparable at the last follow-up regarding their rate of fusion, cervical alignment, JOA recovery rate, SF-36 score, and by Odom's criteria. CONCLUSIONS: For CSM patients undergoing SL-ACCF, the EBM-AVB group demonstrated comparable outcomes regarding patient cervical alignment, neurologic function, and HRQoL in comparison with the TMC group. Furthermore, the use of EBM-AVB was associated with decreased loss of the height of the fusion mass and a lower rate for severe implant subsidence.

Sagittal en bloc resection of primary tumors in the thoracic and lumbar spine: feasibility, safety and outcome.

This study is to test feasibility, safety and the outcome of sagittal en bloc resection of paravertebral primary tumors in the thoracic and the lumbar spine. Sagittal en bloc resection was planned based on WBB classification and performed via combined anterior-posterior or anterior-posterior-lateral approach in 9 consecutive patients with aggressive benign or malignant paravertebral primary tumors in the thoracic and lumbar spine. Surgical margins were evaluated both radiologically and histopathologically. Follow-up data regarding survival rate, local control, morbidity, hardware failure and postoperative function were collected at around 2 years after surgery. En bloc resection was achieved in all patient with wide margin in 7/9 patients, marginal and intralesional margin in 2/9 patients. Survival rate and local control rate were 100%. There were 4/9 cases of major complications and 2/9 cases of minor complications with an overall morbidity rate of 67% (6/9). All but one patient with intraoperative spinal cord injury were free of neurological deficits and fully mobile in absence of any indication of hardware failure. With a careful choice of surgical procedure, sagittal en bloc resection of paravertebral primary tumor in the thoracic and lumbar spine is feasible, safe and effective.

Upper cervical spine reconstruction using customized 3D-printed vertebral body in 9 patients with primary tumors involving C2.

BACKGROUND: Reconstruction following resection of the primary tumors of the upper cervical spine is challenging, and conventional internal implants develop complications in this region. 3D printing, also known as additive manufacturing, can produce patient-specific porous implants in a particular shape for bone defect reconstruction. This study aimed to describe the clinical outcomes of upper cervical spine reconstruction using customized 3D-printed vertebral body in 9 patients with primary tumors involving C2. METHODS: Patients with primary tumors involving C2 who were treated in our institution between July 2014 and November 2018 were enrolled. A two-stage intralesional spondylectomy was performed using the posterior-anterior approach. Anterior reconstruction was accomplished using a customized 3D-printed vertebral body, which was fabricated by successive layering of melted titanium alloy powder using electron beam melting. No bone graft was used. RESULTS: Nine patients (2 males and 7 females) were included in the study with a mean age of 31.4 years (12 to 59 years). Seven patients demonstrated tumors located in C2 and 2 showed involvement of C2 and C3. During a mean follow-up of 28.6 months (range, 12-42 months), 1 patient died of systemic metastasis and 1 had local tumor recurrence, the other 7 patients were alive and functional in their daily living until the last follow-up without evidence of disease. The 3D-printed vertebral bodies were all stable with no sign of displacement or subsidence, evidence of implant osseointegration was observed on the imaging studies. For the posterior instrumentation systems, no screw loosening or rod breakage was found. CONCLUSIONS: Spinal reconstruction in the upper cervical region using customized 3D-printed vertebral body is reliable. The tailored shape matching with the contact surfaces and the porous structure conductive to osseointegration provide both short- and long-term stability to the implant.

Risk Factors for Instrumentation Failure After Total En Bloc Spondylectomy of Thoracic and Lumbar Spine Tumors Using Titanium Mesh Cage for Anterior Reconstruction.

OBJECTIVE: The present study investigated the risk factors for instrumentation failure (IF) after total en bloc spondylectomy (TES) of thoracic and lumbar spine tumors using a titanium mesh cage (TMC) for anterior reconstruction. METHODS: The data from patients who had undergone TES for thoracic and lumbar spine tumors in our institution were retrospectively reviewed. Anterior reconstruction was performed using a TMC filled with morcelized allograft or morcelized autograft. Posterior reconstruction was performed using pedicle fixation. Survival analysis from TES to IF was conducted. The Kaplan-Meier method was used for univariate analysis. Factors of statistical significance were included in the multivariate analysis using Cox regression analysis. RESULTS: A total of 30 patients (20 men and 10 women), with a mean age of 37.1 ± 14.3 years (range, 14-65 years) were included. The mean follow-up period was 41.8 ± 21.3 months (range, 13-120 months). Bone fusion was achieved in 23 patients (76.7%). IF occurred in 8 patients. The mean interval from TES to the first IF was 31.8 ± 15.1 months (range, 13-64 months). On univariable analysis, a body mass index >28 kg/m2, perioperative radiotherapy, and the TMC in an oblique position were associated with IF. On multivariable analysis, these 3 factors were entered into the Cox regression model and were also significant. CONCLUSIONS: The use of TES can achieve durable oncological control. However, IF, a not uncommon late complication that leads to reoperation, should be a cause for concern. We found perioperative radiotherapy, a TMC in an oblique position, and a body mass index >28 kg/m2 were significant predictive factors for IF.

Percutaneous radiofrequency ablation versus open surgical resection for spinal osteoid osteoma.

BACKGROUND CONTEXT: Both open surgical resection (OSR) and radiofrequency ablation (RFA) have been reported for spinal osteoid osteoma (OO). PURPOSE: To verify the clinical safety and efficiency of RFA with OSR in treating spinal OO. STUDY DESIGN: Retrospective cohort study. PATIENT SAMPLE: Twenty-eight consecutive patients with spinal OO who underwent either RFA or OSR in our institute between September 2006 and December 2016. OUTCOME MEASURES: The age, gender, lesion distribution, surgical time, estimated blood loss, complications, local recurrence, visual analogue scale (VAS), and the modified Frankel grade were documented. METHODS: We retrospectively reviewed 28 patients with spinal OO who had been treated in our hospital from September 2006 to December 2016. Patients were followed at 3, 6, 12, and 24 months after the index surgery. The minimum follow-up period was 12 months. This study was funded by Peking University Third Hospital (Y71508-01) (¥ 400,000). RESULTS: Twelve and 16 patients were treated with CT-guided percutaneous RFA and OSR, respectively. Spinal OO locations were cervical in 4, thoracic in 4, lumbar in 3, and sacral vertebra in 1 in the RFA group and cervical in 12, thoracic in 1, and lumber in 3 in the OSR group. RFA showed shorter operating time, less blood loss, and less in-hospital stay than open surgery [105.0 ± 33.8 minutes vs. 186.4 ± 53.5 minutes (p < .001), 1 (0 to 5) ml vs. 125 (30-1200) ml (p < .001) and 1 (1-3) days vs. 6 (3-10) days (p < .001), respectively]. At last follow-up, one patient underwent a secondary RFA for recurrence. VAS improvement was 7.5 (3-10) and 6.5 (4-9) (p = .945) in the RFA and OSR groups, respectively. The overall complication rate was 8.3% (1/12) and 18.8% (3/16) in the RFA and OSR groups, respectively. CONCLUSIONS: If there is sufficient cerebrospinal fluid between the spinal OO lesion and spinal cord/nerve root (more than 1 mm), RFA is effective and safe for treatment of well-selected spinal OO, showing reduced operating time, blood loss, in-hospital stay, and complications compared to OSR. However, OSR is still recommended in cases with spinal cord/nerve root compression.

Clinical features and treatment outcomes of Langerhans cell histiocytosis of the spine.

BACKGROUND CONTEXT: Langerhans cell histiocytosis (LCH) of the spine is a relatively rare condition with unknown etiology. The diagnosis and treatment protocols for spine LCH remain controversial. PURPOSE: In this study, we evaluated the efficacy and safety of our proposed diagnosis and treatment protocol introduced in 2009. STUDY DESIGN: This is a retrospective study. PATIENT SAMPLE: A total of 110 patients with spine LCH who had been diagnosed and treated in our hospital from October 1997 to November 2015 were included in this study. OUTCOME MEASURES: The age, gender, symptoms, neurologic function, lesion distribution, radiological features, pathology, treatment, outcome, and treatment complications of the patients were collected. Visual analog scale (VAS) for pain and Frankel scale for neurologic status were also documented. METHODS: We retrospectively reviewed 110 patients with spine LCH who had been diagnosed and treated in our hospital from October 1997 to November 2015. The indications for computed tomography (CT)-guided biopsy and surgery for spine LCH have become more stringent since 2009. In cases of a solitary spinal lesion, immobilization and observation were usually first suggested. Chemotherapy was suggested for cases with multifocal LCH lesions, and low-dosage radiotherapy was restricted to recurrent solitary lesion. This project was supported by our hospital (No. Y71508-01) (¥ 400,000). RESULT: This series included 69 male and 41 female patients (age range, 1-52 years). Pain was the most common symptom (93.6%, 103/110). Pathologic diagnosis was achieved in 72 cases (65.5%). CT-guided biopsies were performed in 91.3% (42/46) and 73.2% (41/56) of cases before and after 2009, respectively (p=.02). Ninety-eight cases (89.1%) were followed up for a mean 66.3 (range, 24-159) months. Immobilization and observation were performed in 25.9% (14/54) and 75.0% (42/56) of cases before and after 2009, respectively (p<.001). Approximately 35.2% (19/54) and 10.7% (6/56) of cases had surgery (p=.002) before and after 2009, respectively. During the follow-up, no significant difference was found in the outcomes between the two groups treated before and after 2009 (p=.64). CONCLUSION: Biopsy is not mandatory for typical spine lesions of LCH. Given the self-healing tendency of spine LCH, immobilization and observation remain the first-choice treatments for LCH lesions. Conservative biopsy and treatment protocols might be more appropriate for spinal LCH.

Surgical approach selection for total spondylectomy for the treatment of giant cell tumors in the lumbar spine: A retrospective analysis of 12 patients from a single center.

AIM: To describe the selection of the surgical approach used for total spondylectomy in the treatment of giant cell tumors of the lumbar spine. METHODS: This retrospective study included 12 patients with giant cell tumors of the lumbar spine who underwent total spondylectomy. The effect of the Weinstein-Boriani-Biagini surgical staging and tumor location on the approach selected was evaluated. RESULTS: Two tumors were treated using the posterior approach: one located in L1, extending into layers A∼D and involving sectors 2∼6, and the other located in L4, extending into layers B∼D and involving sectors 4∼11. Four tumors (one each located in L1, L2, L3, and L4) were treated by a combined posterior and anterolateral approach as the tumors involved sectors 5∼6 or 7∼8. Six tumors were treated using a combined posterior and anterior approach, two tumors located in L4, extending into layers A∼D and involving sectors 1∼12, and associated with a soft tissue mass extending into layer A and involving sectors 5∼8; and four tumors located in L5. Complications were observed in 9 of the 12 patients. CONCLUSIONS: A posterior approach is the obvious strategy for tumors located in L1∼L4 and extending into layers B∼D or A and involving sectors 1∼3 or 10∼12. For tumors invading beyond layer A and involving sectors 1∼12, including those with a soft tissue mass extending from layer A, with involvement of sectors 4∼9, a posterior approach combined with an anterolateral or anterior approach is required. For L5 tumors, a combined posterior and anterior approach is needed.

Surgical complications of extraspinal tumors in the cervical spine: a report of 110 cases and literature review.

PURPOSE: To assess the safety of surgical intervention for extraspinal tumors in the cervical spine. METHODS: 110 consecutive patients were enrolled and followed-up at least 12 months or until death. The complication rates and risk factors were documented and analyzed. RESULTS: The quality of life in the surviving patients was significantly improved. The overall local recurrence rate was 17.3%. Twenty percent of patients developed distant metastasis. The perioperative mortality rate (30 days after surgery) was 0.9%. The complication related mortality was 1.8%. The rates of overall complication and major complication were 41.8% and 20.9%, respectively. The independent predictors for overall complications were Karnofsky score <60, multisegmental resection, and operation time >3 h. The independent predictors of major complications were comorbidity, tumor location at C1-C2, and combined approach. CONCLUSIONS: Surgery for cervical spine tumor could improve the quality of life, though it might be accompanied with high morbidity and mortality. It is a highly demanding procedure; however, it can be performed to an acceptable degree of safety.

An Approach to Primary Tumors of the Upper Cervical Spine With Spondylectomy Using a Combined Approach: Our Experience With 19 Cases.

STUDY DESIGN: A retrospective study. OBJECTIVE: To examine the link between major complications, surgical techniques, and perioperative care in the intralesional spondylectomy of the upper cervical spine. SUMMARY OF BACKGROUND DATA: Spondylectomy has been demonstrated to prolong cancer-free survival in many patients with locally aggressive spinal tumors. However, the challenging nature of this surgical procedure and the potential for severe complications often limit its application in the upper cervical spine. METHODS: Nineteen patients with primary upper cervical tumors were treated with spondylectomy from March 2005 to August 2009, using either the anterior-posterior or posterior-anterior approach. Anterior procedures were transmandibular, transoral, or high retropharyngeal. Anterior reconstructions were performed in plates with iliac crest strut grafts, plates with mesh cages, and Harms mesh cages alone. Occipitocervical fixation was performed with Halo-vest application for postoperative immobilization. RESULTS: Vertebral artery injuries occurred unilaterally in 5 cases intraoperatively: 4 occurred in the anterior approach of anterior-posterior procedures. Fusion was achieved in 9 patients with intact internal instrumentation. Fusion with the anterior construct in a tilted position occurred in 3 patients, all of whom underwent anterior-posterior procedures with Halo-vest immobilization for less than 1 month. Nonunion occurred in 3 cases after the posterior-anterior procedure because of anterior bone graft absorption. Prolonged Halo-vest immobilization maintained postoperative stability. Failure of internal instrumentation occurred in 3 cases. Anterior construct dislocation and severe tilting occurred in 2 cases after the anterior-posterior procedure. Five patients had a local recurrence. All recurrent lesions were malignant tumors and occurred in regions where surgical exposure was inadequate with incomplete excision. CONCLUSION: The order of the surgical approach is a critical determinant of complications, fusion rates, choice of surgical technique, and reconstruction methods. The postoperative use of a Halo-vest is recommended. Local recurrence is associated with tumor malignancy and inadequate excision margin. LEVEL OF EVIDENCE: 4.

iASPP overexpression is associated with clinical outcome in spinal chordoma and influences cellular proliferation, invasion, and sensitivity to cisplatin in vitro.

The oncogenetic function of inhibitory member of the apoptosis stimulating protein of p53 family (iASPP) in chordoma is unclear and remains to elucidate. The expression of iASPP in chordoma tissues and cells, its correlation to clinicopathological parameters and the effect on the patients' prognosis were evaluated. Cellular proliferation, invasion and cisplatin-response were observed after the iASPP knockdown or overexpression in vitro. Co-Immunoprecipitation assay was used to explore the interaction between iASPP and p53. The regulation of miRNA-124 on the expression and apoptotic function of iASPP was explored after transiently transfecting cells with miRNA-124 mimics or inhibitor. Results indicated that iASPP overexpressed in chordoma tissues and cells. Its overexpression was associated with tumor invasion and local recurrence, and was predictive of patients' poor prognosis. Cells with iASPP-silence showed a decreased ability of proliferation and invasion, but an increasing sensitivity to cisplatin. Besides, iASPP could combine with p53 in either endogenous or exogenous detection. Post-transcriptionally, miRNA-124 negatively regulated the expression of iASPP, which further led to the changes of apoptosis-related proteins. Thus, iASPP overexpression is associated with the clinical outcome in spinal chordoma and influences cellular proliferation, invasion, and the sensitivity to cisplatin.

Prognostic Factors in Surgical Patients with Chordomas of the Cervical Spine: A Study of 52 Cases from a Single Institution.

BACKGROUND: The recurrence rate of cervical chordomas is high, and hence it is important to discern the prognostic factors for local relapse and overall survival (OS). METHODS: A retrospective review of 52 patients with cervical chordoma operated in our institution from January 1999 to March 2015 was performed. The association of clinicopathologic characteristics with local relapse-free survival (LRFS) and OS was analyzed. Univariate analysis was performed to determine whether tumor characteristics and types of therapy affected prognosis, and a multivariate Cox proportional hazard model was developed to further investigate local recurrence and mortality. RESULTS: Mean follow-up time was 50 months. The cumulative 5- and 10-year LRFS was 35 and 0%, respectively, while the cumulative 5- and 10-year OS was 69 and 53%, respectively. The univariate analysis identified contiguous segments involved, intralesional surgical margin at primary surgery, primary surgery in local hospital, incisional biopsy, and without adjuvant radiotherapy as negative prognostic factors for LRFS, whereas for OS, only tumor location in the upper cervical spine was statistically significant. In the multivariate analysis, contiguous vertebral segments involved, intralesional surgical margins, and incisional biopsy were identified as negative prognostic factors for LRFS, whereas for OS, again only tumor location in the upper cervical spine was statistically significant. CONCLUSIONS: Contiguous vertebral segments involved, intralesional surgical margin, without adjuvant radiotherapy, and incisional biopsy significantly increase local recurrence, while tumor location in the upper cervical spine significantly increases tumor-related mortality. Thus, computed tomography-guided fine-needle aspiration biopsy and total spondylectomy with marginal excision may improve survival of patients with cervical chordoma.

Recurrence Factors in Giant Cell Tumors of the Spine.

BACKGROUND: Giant cell tumors (GCTs) are benign, locally aggressive tumors. We examined the rate of local recurrence of spinal GCTs and sought to identify recurrence factors in patients who underwent surgery. METHODS: Between 1995 and 2014, 94 mobile spine GCT patients were treated at our hospital, comprising 43 male and 51 female patients with an average age of 33.4 years. Piecemeal intralesional spondylectomy and total en bloc spondylectomy (TES) were performed. Radiotherapy was suggested for recurrent or residual GCT cases. Since denosumab was not available before 2014 in our country, only interferon and/or zoledronic acid was suggested. RESULTS: Of the 94 patients, four underwent conservative treatment and 90 underwent operations. Seventy-five patients (79.8%) were followed up for a minimum of 24 months or until death. The median follow-up duration was 75.3 months. The overall recurrence rate was 37.3%. Ten patients (13.3%) died before the last follow-up (median: 18.5 months). Two patients (2.6%) developed osteogenic sarcoma. The local recurrence rate was 80.0% (24/30) in patients who underwent intralesional curettage, 8.8% (3/34) in patients who underwent extracapsular piecemeal spondylectomy, and 0 (0/9) in patients who underwent TES. The risk factors for local recurrence were lesions located in the cervical spine (P = 0.049), intralesional curettage (P < 0.001), repeated surgeries (P = 0.014), and malignancy (P < 0.001). Malignant transformation was a significant risk factor for death (P < 0.001). CONCLUSIONS: Cervical spinal tumors, curettage, and nonintact tumors were risk factors for local recurrence. Intralesional curettage and malignancy were the most important significant factors for local recurrence and death, respectively.

A Cross-sectional Study on the Symptom Burden of Patients With Spinal Tumor: Validation of the Chinese Version of the M.D. Anderson Symptom Inventory-Spine Tumor Module.

CONTEXT: Tumors involving the spine are associated with unique symptoms affecting both patient survival and health-related quality of life. Currently, there is no disease-specific instrument in Chinese to assess the symptom burden of these patients. OBJECTIVES: The objective of this study was to translate and validate a Chinese version of the M.D. Anderson Symptom Inventory-Spine Tumor Module (MDASI-SP-C) to assess the symptom burden of Chinese-speaking patients with spinal tumors. METHODS: MDASI-SP-C was forward-and-backward translated according to standard protocols and administered to patients fulfilling study criteria at a major referral center of spine tumor between November 2014 and September 2015. The generic instruments of Short Form 36 Quality of Life Questionnaire (SF-36), Functional Assessment of Cancer Therapy-General Version (FACT-G), and Karnofsky Performance Scale were used along with MDASI-SP-C. Prevalence and severity distribution of each item were analyzed. Psychometric assessment and hierarchical cluster analysis were performed for the translated instrument. RESULTS: One hundred forty-two patients were enrolled. High interdependency and relatively low intra-cluster distances were identified. Cronbach's alpha of the entire instrument, the symptom severity subscale, and the interference subscale was 0.93, 0.91, and 0.92, respectively. Principal axis factoring resulted in a four-factor solution, which was reduced to a three-factor (general symptoms, spine-specific symptoms, and gastrointestinal symptoms) solution on account of clinical interpretation. Correlation coefficients between MDASI-SP-C items and their corresponding domains in SF-36 and/or FACT-G were all greater than 0.3. MDASI-SP-C was able to distinguish patients with different Karnofsky Performance Scale levels. CONCLUSION: MDASI-SP-C demonstrated satisfactory psychometric properties and could be used to better assess the symptom burden of Chinese-speaking patients with spine tumors for improved management of their medical needs.