Risks for prolonged mechanical ventilation and reintubation after cervical malignant tumor surgery: a nested case-control study.

PURPOSE: Prolonged mechanical ventilation (PMV) and reintubation are among the most serious postoperative adverse events associated with malignant cervical tumors. In this study, we aimed to clarify the incidence, characteristics, and risk factors for PMV and reintubation in target patients. METHODS: This retrospective nested case-control study was performed between January 2014 and January 2020 at a large spinal tumor center in China. Univariate analysis was used to identify the possible risk factors associated with PMV and reintubation. Logistic regression analysis was performed to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) with covariates of a probability < 0.05 in univariate analysis. RESULTS: From a cohort of 560 patients with primary malignant (n = 352) and metastatic (n = 208) cervical tumors, 27 patients required PMV and 20 patients underwent reintubation. The incidence rates of PMV and reintubation were 4.82% and 3.57%, respectively. Three variables (all p < 0.05) were independently associated with an increased risk of PMV: Karnofsky Performance Status < 50 compared to ≥ 80, operation duration ≥ 8 h compared to < 6 h, and C4 nerve root encased by the tumor. Longer operative duration and preoperative hypercapnia (all p < 0.05) were independent risk factors for postoperative reintubation, both of which led to longer length of stay (32.6 ± 30.8 vs. 10.7 ± 5.95 days, p < 0.001), with an in-hospital mortality of 17.0%. CONCLUSION: Our results demonstrate the risk factors for PMV or reintubation after surgery for malignant cervical tumors. Adequate assessment, early detection, and prevention are necessary for this high-risk population.

The role of LOXL2 in tumor progression, immune response and cellular senescence: a comprehensive analysis.

LOXL2, an enzyme belonging to the LOX family, facilitates the cross-linking of extracellular matrix (ECM) elements. However, the roles of the LOXL2 gene in mechanisms of oncogenesis and tumor development have not been clearly defined. In this pan-cancer study, we examined the notable disparity in LOXL2 expression at the mRNA and protein levels among various cancer types and elucidated its interconnected roles in tumor progression, mutational profile, immune response, and cellular senescence. Apart from investigating the hyperexpression of LOXL2 being related to poorer prognosis in different types of tumors, this study also unveiled noteworthy connections between LOXL2 and genetic mutations, infiltration of tumor immune cells, and genes in immune checkpoint pathways. Further analysis revealed the participation of LOXL2 in multiple pathways related to cancer extracellular matrix remodeling and cellular senescence. Moreover, our investigation uncovered that the knockdown and inhibition of LOXL2 significantly attenuated the proliferation and migration of PC-9 and HCC-LM3 cells. The knock-down and inhibition of LOXL2 enhanced cellular senescence in lung and liver cancer cells, as confirmed by SA-ß-Gal staining and quantitative RT-PCR analyses. This comprehensive analysis offers valuable insights on the functions of LOXL2 in different types of cancer and its role in regulating the senescence of cancer cells.

miR-1246 promotes osteosarcoma cell migration via NamiRNA-enhancer network dependent on Argonaute 2.

High metastatic propensity of osteosarcoma leads to its therapeutic failure and poor prognosis. Although nuclear activation miRNAs (NamiRNAs) are reported to activate gene transcription via targeting enhancer and further promote tumor metastasis, it remains uncertain whether NamiRNAs regulate osteosarcoma metastasis and their exact mechanism. Here, we found that extracellular vesicles of the malignant osteosarcoma cells (143B) remarkably increased the migratory abilities of MNNG cells representing the benign osteosarcoma cells by two folds, which attributed to their high miR-1246 levels. Specially, miR-1246 located in nucleus could activate the migration gene expression (such as MMP1) to accelerate MNNG cell migration through elevating the enhancer activities via increasing H3K27ac enrichment. Instead, MMP1 expression was dramatically inhibited after Argonaute 2 (AGO2) knockdown. Notably, in vitro assays demonstrated that AGO2 recognized the hybrids of miR-1246 and its enhancer DNA via PAZ domains to prevent their degradation from RNase H and these protective roles of AGO2 may favor the gene activation by miR-1246 in vivo. Collectively, our findings suggest that miR-1246 could facilitate osteosarcoma metastasis through interacting with enhancer to activate gene expression dependent on AGO2, highlighting the nuclear AGO2 as a guardian for NamiRNA-targeted gene activation and the potential of miR-1246 for osteosarcoma metastasis therapy.

MOCS, a novel classifier system integrated multimoics analysis refining molecular subtypes and prognosis for skin melanoma.

PURPOSE: The present investigation focuses on Skin Cutaneous Melanoma (SKCM), a melanocytic carcinoma characterized by marked aggression, significant heterogeneity, and a complex etiological background, factors which collectively contribute to the challenge in prognostic determinations. We defined a novel classifier system specifically tailored for SKCM based on multiomics. METHODS: We collected 423 SKCM samples with multi omics datasets to perform a consensus cluster analysis using 10 machine learning algorithms and verified in 2 independent cohorts. Clinical features, biological characteristics, immune infiltration pattern, therapeutic response and mutation landscape were compared between subtypes. RESULTS: Based on consensus clustering algorithms, we identified two Multi-Omics-Based-Cancer-Subtypes (MOCS) in SKCM in TCGA project and validated in GSE19234 and GSE65904 cohorts. MOCS2 emerged as a subtype with poor prognosis, characterized by a complex immune microenvironment, dysfunctional anti-tumor immune state, high cancer stemness index, and genomic instability. MOCS2 exhibited resistance to chemotherapy agents like erlotinib and sunitinib while sensitive to rapamycin, NSC87877, MG132, and FH355. Additionally, ELSPBP1 was identified as the target involving in glycolysis and M2 macrophage infiltration in SKCM. CONCLUSIONS: MOCS classification could stably predict prognosis of SKCM; patients with a high cancer stemness index combined with genomic instability may be predisposed to an immune exhaustion state.Communicated by Ramaswamy H. Sarma.

A retrospective study on the mechanism underlying quick transfer from response to resistance in a repeated recurrent chordoma patient with molecular alterations treated with Palbociclib.

PURPOSE: There is no approved targeted therapy for chordoma at present. Although several preclinical studies have implied the potential applicability of CDK4/6 inhibitor for this rare tumor, no clinical evidence has been documented so far. The purpose of this study was to elucidate the therapeutic efficacy of CDK4/6 inhibitor for chordoma. METHODS: The next generation sequencing (as for whole-exome sequencing, WES assay) and immunohistochemical (IHC) staining of the chordoma tissue from a patient with an advanced lesion were performed before treatment. Then, the patient was treated with Palbociclib for 4 months until progression occurred in the 5th month. Surgical resection was implemented and the tumor tissue was obtained postoperatively for assessment of molecular alterations. RESULTS: Molecular features of the tumor before medical treatment suggested applicability of CDK4/6 inhibitor and the patient showed partial response (PR) according to Choi Criteria after 4 months treating with Palbociclib until progression occurred. Then, a drastic molecular alteration of the tumor as represented by emergence of dramatic E2F amplification, which is known to induce CDK4/6 independent cell-cycle entry and progression after treatment, was detected. The findings in this patient demonstrated tumor evolution under drug pressure. CONCLUSION: The findings of the present study suggest the feasibility of Palbociclib for the clinical treatment of chordoma, and imply the necessity of combination therapies rather single drug administration due to the quick resistance of the tumor to Palbociclib treatment.

Identification and Verification of Novel Biomarkers Involving Rheumatoid Arthritis with Multimachine Learning Algorithms: An In Silicon and In Vivo Study.

Background: Rheumatoid arthritis (RA) remains one of the most prevalent chronic joint diseases. However, due to the heterogeneity among RA patients, there are still no robust diagnostic and therapeutic biomarkers for the diagnosis and treatment of RA. Methods: We retrieved RA-related and pan-cancer information datasets from the Gene Expression Omnibus and The Cancer Genome Atlas databases, respectively. Six gene expression profiles and corresponding clinical information of GSE12021, GSE29746, GSE55235, GSE55457, GSE77298, and GSE89408 were adopted to perform differential expression gene analysis, enrichment, and immune component difference analyses of RA. Four machine learning algorithms, including LASSO, RF, XGBoost, and SVM, were used to identify RA-related biomarkers. Unsupervised cluster analysis was also used to decipher the heterogeneity of RA. A four-signature-based nomogram was constructed and verified to specifically diagnose RA and osteoarthritis (OA) from normal tissues. Consequently, RA-HFLS cell was utilized to investigate the biological role of CRTAM in RA. In addition, comparisons of diagnostic efficacy and biological roles among CRTAM and other classic biomarkers of RA were also performed. Results: Immune and stromal components were highly enriched in RA. Chemokine- and Th cell-related signatures were significantly activated in RA tissues. Four promising and novel biomarkers, including CRTAM, PTTG1IP, ITGB2, and MMP13, were identified and verified, which could be treated as novel treatment and diagnostic targets for RA. Nomograms based on the four signatures might aid in distinguishing and diagnosing RA, which reached a satisfactory performance in both training (AUC = 0.894) and testing (AUC = 0.843) cohorts. Two distinct subtypes of RA patients were identified, which further verified that these four signatures might be involved in the immune infiltration process. Furthermore, knockdown of CRTAM could significantly suppress the proliferation and invasion ability of RA cell line and thus could be treated as a novel therapeutic target. CRTAM owned a great diagnostic performance for RA than previous biomarkers including MMP3, S100A8, S100A9, IL6, COMP, LAG3, and ENTPD1. Mechanically, CRTAM could also be involved in the progression through immune dysfunction, fatty acid metabolism, and genomic instability across several cancer subtypes. Conclusion: CRTAM, PTTG1IP, ITGB2, and MMP13 were highly expressed in RA tissues and might function as pivotal diagnostic and treatment targets by deteriorating the immune dysfunction state. In addition, CRTAM might fuel cancer progression through immune signals, especially among RA patients.

Kisspeptin-10 binding to Gpr54 in osteoclasts prevents bone loss by activating Dusp18-mediated dephosphorylation of Src.

Osteoclasts are over-activated as we age, which results in bone loss. Src deficiency in mice leads to severe osteopetrosis due to a functional defect in osteoclasts, indicating that Src function is essential in osteoclasts. G-protein-coupled receptors (GPCRs) are the targets for ∼35% of approved drugs but it is still unclear how GPCRs regulate Src kinase activity. Here, we reveal that GPR54 activation by its natural ligand Kisspeptin-10 (Kp-10) causes Dusp18 to dephosphorylate Src at Tyr 416. Mechanistically, Gpr54 recruits both active Src and the Dusp18 phosphatase at its proline/arginine-rich motif in its C terminus. We show that Kp-10 binding to Gpr54 leads to the up-regulation of Dusp18. Kiss1, Gpr54 and Dusp18 knockout mice all exhibit osteoclast hyperactivation and bone loss, and Kp-10 abrogated bone loss by suppressing osteoclast activity in vivo. Therefore, Kp-10/Gpr54 is a promising therapeutic target to abrogate bone resorption by Dusp18-mediated Src dephosphorylation.

Long-term postoperative outcomes of spinal cellular schwannoma: study of 93 consecutive cases.

BACKGROUND CONTEXT: Cellular schwannoma (CS) is a rare tumor that accounts for 2.8%-5.2% of all benign schwannomas. There is a dearth of up-to-date information on spinal CS in the literature. PURPOSE: The aims of this study were to identify the proportion of CS cases amongst spinal benign schwannoma, describe the clinical features of spinal CS, and identify prognostic factors for local recurrence by analyzing data from 93 consecutive CS cases. STUDY DESIGN: Retrospective review. PATIENT SAMPLE: We analyzed 93 PSGCT screened from 1,706 patients with spine CS who were treated at our institute between 2008 and 2021. OUTCOME MEASURES: Demographic, radiographic, operative and postoperative data were recorded and analyzed. METHODS: We compared the clinical features of spinal CS from the cervical, thoracic, lumbar and sacral segments. Prognostic factors for local recurrence-free survival (RFS) were identified by the Kaplan-Meier method. Factors with p≤.05 in univariate analysis were subjected to multivariate analysis by Cox regression analysis. RESULTS: The proportion of spinal CS in all benign schwannomas was 6.7%. The mean and median follow-up times for the 93 patients in this study were 92.2 and 91.0 months respectively (range 36-182 months). Local recurrence was detected in 11 cases, giving an overall recurrence rate of 11.7%, with one patient death. Statistical analysis revealed that tumor size ≥5 cm, intralesional resection, and Ki-67 ≥5% were independent negative prognostic factors for RFS in spinal CS. CONCLUSIONS: Whenever possible, en bloc resection is recommended for spinal CS. Long-term follow-up should be carried out for patients with tumor size ≥5 cm and postoperative pathological Ki-67 ≥5%.

A Novel and Reproducible Classification of Cervical Dumbbell Tumors to Inform Surgical Approach and Reconstruction Techniques.

STUDY DESIGN: A retrospective case series. OBJECTIVE: This study developed a novel classification system based on imaging and anatomy to select optimal surgical approaches and reconstruction strategies to achieve total resection of cervical dumbbell tumors and restore spinal stability. SUMMARY OF BACKGROUND DATA: Total resection is necessary to decrease the recurrence rate of cervical dumbbell tumors. Previous cervical dumbbell tumor classifications are insufficient for determining surgical strategies; therefore, a practical classification is needed. MATERIALS AND METHODS: This study included 295 consecutive patients with cervical dumbbell tumors who underwent total surgical resection. A novel classification of cervical dumbbell tumors was developed based on magnetic resonance imaging and computed tomography. Continuous variables were expressed as mean±SD and were compared using an unpaired two-tailed Student t test. The χ 2 test or the Fisher exact test was used for categorical variables. Kendall's W test assessed three independent raters' inter-rater and intrarater reliabilities on 140 cervical dumbbell tumors. RESULTS: The inter-rater and intrarater consistency coefficient was 0.969 (χ 2 =404.3, P <0.001) and 0.984 (χ 2 =273.7, P <0.001). All patients with type I and II tumors underwent single-posterior surgeries to achieve total resection. Of the patients in this study, 86.1%, 25.9%, 75.9%, and 76.9% underwent posterior surgeries for types IIIa, IIIb, IVa, and V tumors, respectively. All patients with type IVb tumors underwent a combined anterior and posterior approach. Posterior internal fixation was used for all patients in posterior surgery. Anterior reconstruction was applied for patients with type IVb tumors (20/20, 100%) and some with type V tumors (3/13, 23.1%). The mean follow-up duration was 93.6±2.6 months. A recurrence was observed in 19 (6.4%) patients. CONCLUSION: The authors describe a novel classification system that is of practical use for planning the complete resection of cervical dumbbell tumors.

Regulating Chondro-Bone Metabolism for Treatment of Osteoarthritis via High-Permeability Micro/Nano Hydrogel Microspheres.

Destruction of cartilage due to the abnormal remodeling of subchondral bone (SB) leads to osteoarthritis (OA), and restoring chondro-bone metabolic homeostasis is the key to the treatment of OA. However, traditional intra-articular injections for the treatment of OA cannot directly break through the cartilage barrier to reach SB. In this study, the hydrothermal method is used to synthesize ultra-small size (≈5 nm) selenium-doped carbon quantum dots (Se-CQDs, SC), which conjugated with triphenylphosphine (TPP) to create TPP-Se-CQDs (SCT). Further, SCT is dynamically complexed with hyaluronic acid modified with aldehyde and methacrylic anhydride (AHAMA) to construct highly permeable micro/nano hydrogel microspheres (SCT@AHAMA) for restoring chondro-bone metabolic homeostasis. In vitro experiments confirmed that the selenium atoms scavenged reactive oxygen species (ROS) from the mitochondria of mononuclear macrophages, inhibited osteoclast differentiation and function, and suppressed early chondrocyte apoptosis to maintain a balance between cartilage matrix synthesis and catabolism. In vivo experiments further demonstrated that the delivery system inhibited osteoclastogenesis and H-vessel invasion, thereby regulating the initiation and process of abnormal bone remodeling and inhibiting cartilage degeneration in SB. In conclusion, the micro/nano hydrogel microspheres based on ultra-small quantum dots facilitate the efficient penetration of articular SB and regulate chondro-bone metabolism for OA treatment.

Surgical Strategy for Recurrent Giant Cell Tumor in the Thoracolumbar Spine.

OBJECTIVE: Recurrent giant cell tumor (RGCT) of the spine represents a clinical challenge for surgeons, and the treatment strategy remains controversial. This study aims to describe the long-term follow-up outcomes and compare the efficacy of en bloc spondylectomy versus piecemeal spondylectomy in treating RGCT of the thoracolumbar spine. METHODS: A total of 32 patients with RGCT of the thoracolumbar spine treated from June 2012 to June 2019 were retrospectively reviewed. A total of 15 patients received total en bloc spondylectomy (TES) with wide or marginal margin while 17 patients received total piecemeal spondylectomy (TPS) with intralesional margin. Postoperative Eastern Cooperative Oncology Group Performance Score (ECOG-PS), Frankel classification and recurrence-free survival (RFS) were evaluated after surgery. Survival curves were estimated by the Kaplan-Meier method and differences were analyzed with the log-rank test. Multivariate analysis was performed with Cox regression to identify the independent prognostic factors affecting RFS. RESULTS: During a median follow-up of 41.9 ± 17.5 months, all patients with compromised neurologic functions exhibit significant improvement, with the mean ECOG-PS decreasing from 1.5 ± 1.3 to 0.13 ± 0.3 (p < 0.05). Among the 17 patients treated with TPS, eight patients developed local recurrence after a median time of 15.9 ± 6.4 months and four patients died from progressive disease. On the other hand, local recurrence were well managed with TES, since only one out of 15 patients experienced local relapse and all patients are alive with satisfied function at the latest follow-up. The median RFS for patients receiving TES and TPS are 75.0 months (95% CI: 67.5-82.5 m) and 38.3 months (95% CI: 27.3-49.3 m) respectively (p = 0.008). Multivariate analysis shows that the Ki67 index (p = 0.016), resection mode (p = 0.022), and denosumab (p = 0.039) are independent risk factors affecting RFS. CONCLUSIONS: TES with wide/marginal margin should be offered to patients with RGCT whenever feasible, given its long-term benefits in local control and symptom alleviation. Additionally, patients with lower Ki67 index and application of denosumab tend to have a better prognosis.

[Retracted] MicroRNA-493 inhibits the proliferation and invasion of osteosarcoma cells through directly targeting specificity protein 1.

[This retracts the article DOI: 10.3892/ol.2018.8268.].

PRMT1 orchestrates with SAMTOR to govern mTORC1 methionine sensing via Arg-methylation of NPRL2.

Methionine is an essential branch of diverse nutrient inputs that dictate mTORC1 activation. In the absence of methionine, SAMTOR binds to GATOR1 and inhibits mTORC1 signaling. However, how mTORC1 is activated upon methionine stimulation remains largely elusive. Here, we report that PRMT1 senses methionine/SAM by utilizing SAM as a cofactor for an enzymatic activity-based regulation of mTORC1 signaling. Under methionine-sufficient conditions, elevated cytosolic SAM releases SAMTOR from GATOR1, which confers the association of PRMT1 with GATOR1. Subsequently, SAM-loaded PRMT1 methylates NPRL2, the catalytic subunit of GATOR1, thereby suppressing its GAP activity and leading to mTORC1 activation. Notably, genetic or pharmacological inhibition of PRMT1 impedes hepatic methionine sensing by mTORC1 and improves insulin sensitivity in aged mice, establishing the role of PRMT1-mediated methionine sensing at physiological levels. Thus, PRMT1 coordinates with SAMTOR to form the methionine-sensing apparatus of mTORC1 signaling.

Prognostic factors of sarcomas occurring in bone and joint: A SEER based study.

To clarify the epidemiology, treatment, and prognosis of sarcomas occurring in the bones and joints. The surveillance, epidemiology, and end results (SEER) 18 registries, comprising sarcoma diagnoses made between 2008 and 2014, were queried for sarcomas arising in bones or joints. Kaplan-Meier analysis, multivariate logistic regression analysis, Cox proportional hazards model, and nomograms were used to identify prognostic factors. 2794 patients aged from 1 to 99 (55.8% male) with microscopically confirmed diagnosed as sarcomas (including osteosarcoma, chondrosarcoma, Ewing sarcoma, and soft tissue sarcomas) which primary site limited to bone and joint were identified. Eight independent factors, including age, race, sex, tumor site, histology, pathology grade, tumor size, and total number of malignant tumors (TNOMT), were associated with tumor metastasis. Nine independent prognostic factors, including age (>=60 year, hazard ratio [HR] = 4.145, 95% confidence interval [CI], P < .001), sex (female, HR = 0.814, 95%CI, P = .007), tumor site (spine, HR = 2.527, 95%CI, P < .001), histology, pathology grade (undifferentiated, HR = 5.816, 95%CI, P < .001), tumor size (>=20 cm, HR = 3.043, 95%CI, P < .001), tumor extent (distant, HR = 4.145, 95%CI, P < .001), surgery (no performed, HR = 2.436, 95%CI, P < .001), and TNOMT (1, HR = 0.679, 95%CI, P < .001, were identified and incorporated to construct a nomogram for 2- and 5-year overall survival (OS). The calibration curve for the probability of survival showed good agreement between prediction by the nomogram and actual observation. The C-index of the nomogram for survival prediction was 0.814. Patients who received chemotherapy had a significantly decreased risk of death only for Ewing sarcoma, poorly differentiated tumors, undifferentiated tumors, and distant tumor invasion (P < .05). However, radiotherapy did not show significant differences in OS. This study presents population-based estimates of prognosis for patients with bone sarcomas and demonstrates the impact of age, race, sex, tumor site, histology, pathology grade, tumor size, tumor extent, surgery, radiotherapy, chemotherapy, and the TNOMT on OS. Moreover, the nomogram resulted in a more accurate prognostic prediction. However, in our study, radiotherapy showed no survival benefit, perhaps because detailed data on treatment factors were unavailable and which may have influenced the results.

Identification of ARAP3 as a regulator of tumor progression, macrophage infiltration and osteoclast differentiation in a tumor microenvironment-related prognostic model of Ewing sarcoma.

Understanding the specificity and complexity of the tumor microenvironment (TME) of Ewing sarcoma (ES) is essential for identifying the immune characteristics of ES, improving the prediction of immunotherapeutic response, and facilitating therapeutic target discovery. In this study, we not only evaluated the gene sets associated with TME in ES using ESTIMATE and WGCNA algorithms based on the transcriptome data of ES, but also constructed a prognostic model (ES Score) using univariate Cox regression and Lasso regression and assessed its predictive ability on immune cell infiltration. Subsequently, we identified ARAP3 as a key gene affecting the TME of ES. In addition, bioinformatic analyses and in vitro experiments proved that the high expression of ARAP3 regulated ES cell proliferation, migration, as well as apoptosis via the p53 signaling pathway and affected macrophage infiltration and osteoclast differentiation through regulating IL1B and IL11 secretion of tumor cells.

Surgical Outcome and Prognosis of Patients with Spinal Metastasis from Esophageal Cancer: The Experience from a Single Center.

BACKGROUND: The spine is one of the common sites of esophageal cancer metastasis, with a worse prognosis than that of metastasis occurring in other sites. However, the exact mechanism underlying metastatic spinal esophageal cancer (MSEC) is poorly understood possibly due to the short survival time of patients. The aim of this study was to evaluate surgical outcomes and factors affecting the prognosis of patients with MSEC. METHODS: Enrolled in this retrospective study were 20 consecutive patients who received surgical treatment for MSEC in our hospital from 2013 to 2020. The impact of surgery on patient's quality of life was assessed by visual analog scale score and American Spinal Injury Association grade. Prognostic variables relative to traditional clinical parameters and inflammation and nutrition indicators were identified by univariate and multivariate analyses. RESULTS: The median survival time of patients with MSEC was 6 months, with a one-year survival rate of 20%. Pain relief was achieved in most patients, and nerve function was recovered in part of the patients after surgery. Analysis of clinical factors showed that total tumor resection was beneficial to overall survival of patients with MSEC. Laboratory indicators of erythrocyte sedimentation rate, neutrophil/lymphocyte ratio, and platelet/lymphocyte ratio were identified as independent prognostic factors for patients with MSEC. CONCLUSIONS: Timely surgical intervention can improve the quality of life of patients with MSEC. The preoperative erythrocyte sedimentation rate, neutrophil/lymphocyte ratio, and platelet/lymphocyte ratio could help predict the overall survival of patients with MSEC. These findings may help in decision-making for the treatment of patients with MSEC.

3D-printed Titanium Prosthetic Reconstruction of Unilateral Bone Deficiency After Surgical Resection of Tumor Lesions in the Upper Cervical Spine: Clinical Outcomes of Three Consecutive Cases and Narrative Review.

MAIN POINTS: Operational excision of tumor lesions in the upper cervical spine remains a tremendous challenge to surgeons due to the local complex anatomic relationships. Meanwhile, no commercially available device has been specially designed to address bone deficiency after surgical resection. Here, we described the reconstruction of unilateral bone deficiency after surgical resection of a giant cell tumor of the tendon sheath originating from the lateral atlantoaxial joint with the employment of a 3D printing technique and reviewed the relevant literature. In our study, 3 patients with giant cell tumor of the tendon sheath in the upper cervical spine achieved complete tumor removal, and received unilateral bone reconstruction with one-armed 3D-printed titanium prosthesis. During the follow-up, these patients remained neurologically intact and got back to a normal life without wearing the braces. Images demonstrated the satisfactory placement of 3D-printed prosthesis with no failure of fixation and no subsidence. In addition, 6 articles describing the employment of 3D-printed prostheses or models for tumor surgery in the upper cervical spine were reviewed, and satisfactory clinical outcomes were reported in these studies. Hence, 3D-printed titanium prosthetic reconstruction of bone deficiency in the upper cervical spine was a safe and effective technique. LEVEL OF EVIDENCE: Level IV.