Genetic variants associated with osteosarcoma risk: a systematic review and meta-analysis.

Osteosarcoma (OS) is the most common type of primary bone malignancy. Common genetic variants including single nucleotide polymorphisms (SNPs) have been associated with osteosarcoma risk, however, the results of published studies are inconsistent. The aim of this study was to systematically review genetic association studies to identify SNPs associated with osteosarcoma risk and the effect of race on these associations. We searched the Medline, Embase, Scopus from inception to the end of 2019. Seventy-five articles were eligible for inclusion. These studies investigated the association of 190 SNPs across 79 genes with osteosarcoma, 18 SNPs were associated with the risk of osteosarcoma in the main analysis or in subgroup analysis. Subgroup analysis displayed conflicting effects between Asians and Caucasians. Our review comprehensively summarized the results of published studies investigating the association of genetic variants with osteosarcoma susceptibility, however, their potential value should be confirmed in larger cohorts in different ethnicities.

Skeletal involvement in children with Langerhans cell histiocytosis: healing, complications, and functional outcome.

INTRODUCTION: Skeletal involvement in children with Langerhans cell histiocytosis (LCH) is a common feature of the disease. Several options for the treatment of these skeletal lesions have been reported. We describe our experience in the treatment of skeletal involvement of LCH in this retrospective case series study, entailing anatomic distribution, pattern of healing, skeletal deformities, and functional outcome of skeletal LCH. METHODS: A retrospective analysis was conducted for patients diagnosed with LCH and having skeletal lesions in the period between 2007 and 2015. Out of a total of 229 cases, 191 (83.4%) had skeletal involvement. Bone healing was divided into partial and complete based on the size of lesion and cortical changes in plain radiograph. Skeletal deformities were serially measured. Time to pain control, resumption of weight bearing, and the final functional status of the patient were reviewed. RESULTS: The mean age at presentation was 4.4 years (3 m-14.8 y) and the mean follow-up period was 53.3 months (0.2-120.7). After screening of skeletal and extra-skeletal lesions, 59 patients (31%) had M-S (Multisystem) LCH and 132 (69%) had S-S (Single system) LCH. Unifocal bone lesions were found in 81 (42.5%) patients, and multifocal bone lesions in 110 patients (57.5%). Single or multiple bone lesions were found in the craniofacial bones in 152 patients (79.5%), femur in 19 patients, (10%), ribs in 18 patients (9.4%), spine in 15 patients (8.1%), pelvis in 14 patients (7.3%), scapula in 8 patients (4.1%), humerus in 6 (3.1%), clavicle in 6 patients (3.1%), tibia in 3 patients (1.5%), radius in 3 patients (1.5%), and the ulna in 2 patients (1%) patients. No lesions were found in the fibula, hand, or foot. Out of all skeletal lesions, 179 (93.7%) patients were treated either medically or conservatively and 12 patients (6.2%) were treated surgically. The mean time to complete healing was 5.2 months (2-12). Skeletal complications included: pathologic fractures (9 vertebra plana, 5 long bone, 1 iliac bone), deformities (9 thoracolumbar kyphosis, 2 cervical spine subluxations, 2 coxa vara deformity of the proximal femur and one flattening of iliac bone). CONCLUSION: Non-operative treatment can lead to adequate bone healing in few months period. Partial or complete remodeling of bone deformities can be observed without surgical correction. However, surgical intervention might be indicated when cervical spine affection may lead to instability and subsequent neurological affection. Functional impairment is rarely caused by skeletal lesions in LCH.

Reconstruction of the Scapula in Pediatric and Adolescent Patients After Total Scapulectomy. A Report of 10 Patients Treated by Extracorporeal Irradiation and Reimplantation of the Scapula.

BACKGROUND: Ewing sarcoma of the scapula is uncommon. Restoration of shoulder function after total scapulectomy is challenging. Extracorporeal irradiation and reimplantation is a well-known method of biological reconstruction in orthopaedic oncology; yet very few reports in the literature describe its specific use in tumors of the scapula. PATIENTS AND METHODS: Ten patients with the diagnosis of Ewing sarcoma of the scapula were surgically treated by total scapulectomy and extracorporeal irradiation and reimplantation of the scapula. The mean age at presentation was 10 years (3 to 15 y). Six patients were male individuals and 4 were female individuals. An extracorporeal single dose of 5000 cGy was applied to each graft. At reimplantation, internal fixation was used in the first 2 cases, whereas, in the following 8 patients, stabilization was carried out by resuturing of the glenohumeral and acromioclavicular joint capsules without internal fixation. An ipsilateral Latissimus Dorsi muscle flap was used in all patients to cover the irradiated scapula. RESULTS: The mean follow-up duration was 29.2 months (13 to 50 m). At the latest follow-up, 8 patients were continuously disease free and 2 patients had systemic relapse. No patient had local recurrence. The mean musculoskeletal tumor society functional score was 87% (66.6% to 100%). Eight of the 10 patients (80%) could actively elevate the upper limb up to and beyond 90 degrees in both the forward and scapular planes. Complications included wound gaping in 2 patients (20%), dislocation of the acromioclavicular joint in 3 patients (30%), and partial resorption of the scapular graft in 5 patients (50%). No patient showed any progressive deterioration of his or her shoulder function throughout the follow-up period. CONCLUSIONS: The irradiated scapular graft provides a stable biological fulcrum for the reattached muscles of the shoulder joint after total scapulectomy, thereby providing an adequate postoperative range of shoulder elevation. A longer follow-up study is needed to evaluate the progression and effect of graft resorption on the functional outcome. LEVEL OF EVIDENCE: Level IV.