A Web-Based Prediction Model for Overall Survival of Elderly Patients With Malignant Bone Tumors: A Population-Based Study

Background: Malignant bone tumors (MBT) are one of the causes of death in elderly patients. The purpose of our study is to establish a nomogram to predict the overall survival (OS) of elderly patients with MBT.Methods: The clinicopathological data of all elderly patients with MBT from 2004 to 2018 were downloaded from the SEER database. They were randomly assigned to the training set (70%) and validation set (30%). Univariate and multivariate Cox regression analysis was used to identify independent risk factors for elderly patients with MBT. A nomogram was built based on these risk factors to predict the 1-, 3-, and 5-year OS of elderly patients with MBT. Then, used the consistency index (C-index), calibration curve, and the area under the receiver operating curve (AUC) to evaluate the accuracy and discrimination of the prediction model was. Decision curve analysis (DCA) was used to assess the clinical potential application value of the nomogram. Based on the scores on the nomogram, patients were divided into high- and low-risk groups. The Kaplan-Meier (K-M) curve was used to test the difference in survival between the two patients.Results: A total of 1,641 patients were included, and they were randomly assigned to the training set (N = 1,156) and the validation set (N = 485). The univariate and multivariate analysis of the training set suggested that age, sex, race, primary site, histologic type, grade, stage, M stage, surgery, and tumor size were independent risk factors for elderly patients with MBT. The C-index of the training set and the validation set were 0.779 [0.759–0.799] and 0.801 [0.772–0.830], respectively. The AUC of the training and validation sets also showed similar results. The calibration curves of the training and validation sets indicated that the observed and predicted values were highly consistent. DCA suggested that the nomogram had potential clinical value compared with traditional TNM staging.Conclusion: We had established a new nomogram to predict the 1-, 3-, 5-year OS of elderly patients with MBT. This predictive model can help doctors and patients develop treatment plans and follow-up strategies.

Sacrectomy with Ilio-Lumbar Stabilization Due to Low-Grade Chondrosarcoma of Sacrum and Iliac Wing. Case Report of the First Surgery Performed in the Republic of North Macedonia

Low - grade chondrosarcomas are primary malignant bone tumors that are resistant to chemo- and radiotherapy and are treated surgically. Sacral localization makes surgical resection technically difficult due to position, anatomic structures involved, and large tumor size at detection. The risk of complications is high. We present the introduction of a novel surgical technique in our country, sacrectomy with ilio-lumbar stabilization. This was performed on a 67-year-old man with low-grade chondrosarcoma of the sacrum with sacroiliac joint involvement. The procedure was performed via an antero-posterior approach in two stages. Ilio-lumbar fixation with a mesh cage bridge was used to obtain spinopelvic continuity and stability. Sacrectomy is a technically demanding procedure that requires careful preoperative planning and a multidisciplinary approach, as well as high level of surgical experience.

A Web-based Prediction Model for Overall Survival of Elderly Patients With Malignant Bone Tumors: a Population-based Study

Background: Malignant bone tumors(MBT) are one of the causes of death in elderly patients. The purpose of our study is to establish a nomogram to predict the overall survival(OS) of elderly patients with MBT.Methods: The clinicopathological data of all elderly patients with MBT from 2004 to 2018 were downloaded from the SEER database. They were randomly assigned to the training set (70%) and validation set (30%). Univariate and multivariate Cox regression analysis was used to identify independent risk factors for elderly patients with MBT. A nomagram was built based on these risk factors to predict the 1-, 3-, and 5-year OS of elderly patients with MBT. Then, used the consistency index (C-index), calibration curve, and the area under the receiver operating curve(AUC) to evaluate the accuracy and discrimination of the prediction model. Decision curve analysis(DCA) was used to evaluate the clinical potential application value of nomogram. Based on the scores on the nomogram, patients were divided into high- and low-risk groups. Kaplan-Meier (K-M) curve was used to test the difference in survival between the two groups of patients.Results: A total of 1641 patients were included, and they were randomly assigned to the training set (N=1156) and the validation set (N=485). The univariate and multivariate analysis of the training set suggested that age, sex, race, primary site, histologic type, grade, stage, M stage, surgery, and tumor size were independent risk factors for elderly patients with MBT. The C-index of the training set and the validation set were 0.779[0.759-0.799] and 0.801[0.772-0.830], respectively. The AUC of the training set and the validation set also showed similar results. The calibration curves of the training set and the validation set both showed that the observed value and the predicted value were highly consistent. DCA suggested that the nomogram had potential clinical value compared with traditional TNM staging.Conclusion: We had established a new nomogram to predict the 1-, 3-, 5-year OS of elderly patients with MBT. This predictive model can help doctors and patients develop treatment plans and follow-up strategies.

Proximal Femur Versus Acetabular Extra-articular Resection of the Hip Joint for Primary Malignant Bone Tumors : A Retrospective Comparative Review of 33 Cases

Introduction Extra-articular resection (EAR) of the hip joint is prone to significant complications and morbidity. Thus, this study evaluates the cumulative incidences and main reasons of reoperation following EAR of primary bone tumors of the hip to determine whether the outcomes are different between EAR of the pelvis and that of the proximal femur. Patients and methods Thirty-three patients presented with a PMBT of the proximal femur or pelvis were included in this study. Among all PMBTs, 58% originated from the pelvis and 42% were from the proximal femur. Twenty patients had chondrosarcomas (61%), 10 had osteosarcomas (30%), and 3 had sarcomas of another histological subtype (9%). Results The mean follow-up was of 76 months (range: 24–220 months). The cumulative probabilities of revision for any reason was 52% (95% confidence interval [CI]: 30%–70%) five years after surgery. The five-year cumulative probabilities of revision were 13% (95% CI: 4%–27%), 24% (95% CI: 10%–42%) and 34% (95% CI: 14%–56%) for mechanical, infectious and tumoral reasons, respectively. The five-year cumulative probabilities of revision for any reason were 78% (95% CI: 37%–94%) and 14% (95% CI: 2%–38%) for the pelvis and proximal femur, respectively ( p = 0.004). Posterior column preservation was significantly associated with more mechanical complications even after adjusting for the resection site ( p = 0.043). Conclusion Half of patients undergoing EAR of the hip joint for PMBT of the proximal femur or acetabulum will require another operation. EAR of the pelvis is associated with significantly worse outcome than EAR of the proximal femur.

Risk factors and outcomes for failure of biological reconstruction after resection of primary malignant bone tumors in the extremities

Biological reconstruction is widely used to reconstruct bone defects after resection of bone tumors in the extremities. This study aimed to identify risk factors for failure and to compare outcomes of the allograft, nonvascularized autograft, and recycled frozen autograft reconstruction after resection of primary malignant bone tumors in the extremities. A retrospective study was performed at a single center between January 1994 and December 2017. Ninety patients with primary malignant bone tumors of the extremities were treated with tumor resection and reconstruction using one of three bone graft methods: nonvascularized autograft (n = 27), allograft (n = 34), and recycled frozen autograft (n = 29). The median time for follow-up was 59.2 months (range 24–240.6 months). Overall failure of biological reconstruction occurred in 53 of 90 patients (58.9%). The allograft group had the highest complication rates (n = 21, 61.8%), followed by the recycled frozen autograft (n = 17, 58.6%) and nonvascularized autograft (n = 15, 55. 6%) groups. There was no statistically significant difference among these three groups (p = 0.89). The mean MSTS score was 22.6 ± 3.4 in the nonvascularized autograft group, 23.4 ± 2.6 in the allograft group, and 24.1 ± 3.3 in the recycled frozen autograft group. There was no significant difference among the groups (p = 0.24). After bivariate and multivariable analyses, patient age, sex, tumor location, graft length, methods, and type of reconstruction had no effects on the failure of biological reconstruction. Biological reconstruction using allograft, nonvascularized autograft, and recycled frozen autograft provide favorable functional outcomes despite high complication rates. This comparative study found no significant difference in functional outcomes or complication rates among the different types of reconstruction.

Diagnostic performance of PET/CT in primary malignant bone tumors

Background Nowadays, PET/CT plays a substantial role in the diagnosis of different types of tumor by its ability to provide combined functional and anatomic imaging in the same session. The purpose of this study is to evaluate the added value of PET/CT in staging and re-staging of primary malignant bone tumors. Results Out of the studied 40 patients, 7 patients were referred for primary staging of different types of histologically proven primary malignant bone tumors, their FDG-PET/CT studies yielded additional diagnostic information in 28.6% of them. Thirty three patients were referred either for assessment of treatment response or for follow-up to detect any viable lesions; FDG-PET/CT was more sensitive and specific than CT in follow-up and assessment of treatment response with PET/CT sensitivity 94.4%, specificity 86.7%, and total accuracy 90.9% and CT sensitivity 88.2%, specificity 81.2%, and total accuracy 84.8%. Conclusions PET/CT was an accurate imaging modality in evaluation of primary malignant bone tumors regarding tumor staging, assessment of therapeutic response and detection of metastatic disease as compared to CT.