Proximal location in extremity long bones is a poor prognostic factor for osteosarcoma: A retrospective cohort study of 153 patients

Establishment and validation of a competitive risk model for predicting cancer-specific survival in patients with osteosarcoma: a population-based study

BACKGROUND

Osteosarcoma is the most common primary bone tumor with a poor prognosis. The aim of this study was to establish a competitive risk model nomogram to predict cancer-specific survival in patients with osteosarcoma.

METHODS

Patient data was obtained from the Surveillance, Epidemiology, and End Results database in the United States. A sub-distribution proportional hazards model was used to analyze independent risk factors affecting cancer-specific mortality (CSM) in osteosarcoma patients. Based on these risk factors, a competitive risk model was constructed to predict 1-year, 3-year, and 5-year cancer-specific survival (CSS) in osteosarcoma patients. The reliability and accuracy of the nomogram were evaluated using the concordance index (C-index), the area under the receiver operating characteristic curve (AUC), and calibration curves.

RESULTS

A total of 2900 osteosarcoma patients were included. The analysis showed that age, primary tumor site, M stage, surgery, chemotherapy, and median household income were independent risk factors influencing CSM in patients. The competitive risk model was constructed to predict CSS in osteosarcoma patients. In the training and validation sets, the C-index of the model was 0.756 (95% CI 0.725-0.787) and 0.737 (95% CI 0.717-0.757), respectively, and the AUC was greater than 0.7 for both. The calibration curves also demonstrated a high consistency between the predicted survival rates and the actual survival rates, confirming the accuracy and reliability of the model.

CONCLUSION

We established a competitive risk model to predict 1-year, 3-year, and 5-year CSS in osteosarcoma patients. The model demonstrated good predictive performance and can assist clinicians and patients in making clinical decisions and formulating follow-up strategies.

Osteosarcoma of the Mandible in an Elderly Patient

Osteosarcoma is a malignant tumor in which the cancerous cells produce an osteoid matrix or mineralized bone. Jaw bones are affected in 6% of all osteosarcomas and are the fourth most common site of origin. Surgical treatment of osteosarcoma in elderly patients is rarely reported. Here, we report successful treatment of osteosarcoma arising in the mandible of a 90-year-old man. The patient was referred to our institution for diagnosis and treatment of an oral lesion. Intraoral examination revealed that a hard mass measuring 35 × 27 mm was located on the floor of the oral cavity, attached to the bone, and its growth displaced the tongue posteriorly. Therefore, he experienced difficulty in speech and swallowing. Biopsy of the mandibular mass was suspicious for chondrosarcoma. Preoperative examination did not detect critical risks for general anesthesia or surgery. Based on a clinical diagnosis of a malignant bone tumor of the mandible, segmental mandibular resection with reconstruction using a titanium plate was performed. Surgical site infection occurred on postoperative day 12, which was resolved by drainage, local irrigation, and administration of antibiotics. There was no delirium or cardiovascular or pulmonary complications. Surgery resolved the patient's difficulties in speech and swallowing. There was no evidence of tumor recurrence or metastasis 4 years after surgery. This case showed that it was not necessary to exclude surgical treatment merely because the patient was 90 years old. Indications for surgery should be determined individually to improve the patient's quality of life.

Age and Tumor Location Predict Survival in Nonmetastatic Osteosarcoma in Upper Egypt

AIM

The aims of this study were to assess survival outcome of pediatric patients with localized osteosarcoma of the extremities in Upper Egypt, identify factors of prognostic significance for survival, and to determine factors predictive of surgical methods used in these patients, as well as developing a clinical model for risk prediction.

PATIENTS AND METHODS

A retrospective analysis of data assembled from medical records of 30 pediatric patients with a histologically verified nonmetastatic osteosarcoma of the extremities treated at South Egypt Cancer Institute with a unified chemotherapy protocol between January 2001 and December 2015 was carried out. Prognostic factors were determined using univariable and multivariable methods. A model for surgical outcomes in these patients based on the baseline clinical factors, and the parameters predictive of their tumor response to chemotherapy, was developed.

RESULTS

With a median follow-up of 63 months for the study population, the estimates for event-free survival and overall survival (OS) at 3 and 5 years were 69.5% and 79% and 65.2% and 65.3%, respectively. Age 16 years or above was independently associated with both worse metastasis-free survival (hazard ratio [HR]=6.05, 95% confidence interval [CI]: 1.43-25.6, P=0.015) and OS (HR=7.9, 95% CI: 1.71-36.2, P=0.008). In the multivariable analysis, a proximal location within the limb gained a statistical significance to be independently associated with worse OS (HR=2.4, 95% CI: 1.13-22.1, P=0.003). Poor response to chemotherapy was marginally associated with worse metastasis-free survival (HR=4.9, 95% CI: 1.02-23.8, P=0.047) only in the univariable analysis. The patients found to be more likely to undergo an amputation surgery (odds ratio=14.1, 95% CI: 1.34-149.4, P=0.028) were those in whom a tumor was poorly responding to chemotherapy.

CONCLUSION

In Upper Egypt, despite the reasonable survival outcomes in nonmetastatic osteosarcoma, a relatively high limb amputation rate has been encountered. The development of a clinical prediction model for future planning of possible outcome improvement in these patients, however, is still feasible.

Prognostic factors in osteosarcoma: A study level meta-analysis and systematic review of current practice

Background

A consensus has not yet been reached regarding the abilities of gender, age, tumor size, tumor location, histologic subtypes, and surgery in the prediction of survival in osteosarcoma. We aimed to disclose their prognostic significance by conducting a meta-analysis of all the published data from the last decade.

Materials and Methods

Electronic database searches were conducted in PubMed, Embase, and Web of Science for relevant articles published within the last ten years. The pooled hazard ratio (HR) and corresponding 95% confidence interval (CI) were obtained to evaluate the prognostic values of the target factors.

Results

A total of 18,126 patients from 40 studies were eventually included. Results indicated that gender (male vs. female: 1.21, 95% CI, 1.11–1.32; female vs. male: 0.85, 95% CI, 0.75–0.98), age (12–20 vs. ≤12: 1.37, 95% CI, 1.13–1.65; ≥20 vs. <20: 1.29, 95% CI, 1.08–1.55; ≥40 vs. <40: 1.63, 95% CI, 1.21–2.20; ≥50 vs. <25: 2.60, 95% CI, 1.92–3.53; ≥60 vs. <60: 1.11, 95% CI, 1.06–1.18), tumor location (non-extremities vs. extremities: 2.10, 95% CI, 1.76–2.51; proximal vs. distal femur: 3.68, 95% CI: 1.51–8.96; proximal vs. distal humerus: 3.15, 95% CI: 1.53–6.49), tumor size (≥5 vs. <5: 1.42, 95% CI, 1.09–1.86; >8 vs. ≤8: 1.55, 95% CI, 1.07–2.24; >9 vs. ≤9: 1.44, 95% CI, 1.05–1.96), chemotherapy response (poor vs. good: 2.45, 95% CI, 2.02–2.97; good vs. poor: 0.41, 95% CI, 0.34–0.48), and surgery (yes vs. no: 0.45, 95% CI, 0.36–0.57; amputation vs. salvage: 2.34, 95% CI, 1.47–3.74) were significantly associated with overall survival in osteosarcoma patients.

Conclusion

The meta-analysis demonstrated that male patients, older age, large tumor size, non-extremity osteosarcoma, proximal osteosarcoma, poor chemotherapy response, no surgical treatment, and amputation surgery were correlated with a poor prognosis in osteosarcoma patients.

Pediatric Osteosarcoma of Extremities: A 15-year Experience From a Tertiary Care Cancer Center in Upper Egypt

AIM

To assess the outcome and determine predictors of survival in pediatric patients with osteosarcoma of the extremities treated with a unified chemotherapy protocol at a single institution over a 15-year period.

MATERIALS AND METHODS

We performed a retrospective analysis of medical records of 48 pediatric patients with histologically verified osteosarcoma of the extremities diagnosed at South Egypt Cancer Institute and received treatment between January 2001 and December 2015.

RESULTS

With a median follow-up of 61 months for the entire cohort, estimates of overall survival (OS) for 3- and 5-year were 50.9% and 42.1%, respectively. While the estimates of OS for 3- and 5-year in the nonmetastatic group were 79% and 65.2%, respectively. In the multivariable analysis, both metastatic disease at diagnosis and poor response to chemotherapy retained their statistical significance as independent predictors for event-free survival. Whereas for OS, a metastatic disease at diagnosis remained as the lone predictor of a dismal outcome, while a poor response to chemotherapy became marginally associated with an inferior outcome.

CONCLUSIONS

In Upper Egypt, whereas slightly less than two thirds of children with localized osteosarcoma of extremities survives their disease, metastasis at presentation remains the key predictor of dismal survival outcomes.

Simple staging system for osteosarcoma performs equivalently to the AJCC and MSTS systems

Both the American Joint Committee on Cancer (AJCC) and Musculoskeletal Tumor Society (MSTS) staging systems for skeletal sarcomas have major weaknesses. A revised staging system for osteosarcoma (the Vanderbilt system) was developed based on exploratory analyses of the relative prognostic impacts of histologic grade, tumor size, local tumor extension, and specific anatomic sites of metastasis using case records from the National Cancer Database (N = 4,285). AJCC, MSTS, and Vanderbilt staging schemes were then compared using a separate, population-based cancer registry (the Surveillance, Epidemiology, and End Results database; N = 2,246) as a validation dataset. Predictive accuracy for 5-year sarcoma-specific survival was evaluated by comparing areas under receiver-operating characteristic curves generated from logistic regression. Three different concordance indices and Bayesian information criteria were also calculated for model comparisons. The Vanderbilt staging system showed comparable predictive accuracy for 5-year disease-specific survival (65%) compared to the AJCC (67%) and MSTS (67%) staging systems. Most cross-comparisons of model concordance were not significantly different either. Bayesian information criterion was lowest for the MSTS staging system. Substaging osteosarcoma by current anatomical criteria is ineffectual. A simplified staging system based only on histologic grade and the presence of distant metastasis to any anatomic site performs similarly to the current AJCC and MSTS staging systems by multiple statistical criteria and is proposed for clinical and pathological staging of osteosarcomas of the non-pelvic appendicular and non-spinal axial skeleton. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2802-2808, 2018.

Comparison of the AJCC, MSTS, and Modified Spanier Systems for Clinical and Pathologic Staging of Osteosarcoma

The prognostic performance of the 2 most commonly used staging systems for skeletal sarcoma (the American Joint Committee on Cancer [AJCC] and Musculoskeletal Tumor Society [MSTS] systems) have never been compared analytically. Another staging system originally proposed by Spanier has not yet been validated. Given the recent release of the 8th edition of the AJCC Cancer Staging Manual, this study was designed to directly compare these anatomic staging systems in a series of 153 high-grade, intramedullary osteosarcomas. Kaplan-Meier curves were plotted and pairwise comparisons between each stage category were performed. Predictive accuracy of each staging system for determining 5-year disease-free survival was evaluated by comparing areas under receiver-operating characteristic curves generated from logistic regression analysis. Multiple concordance indices were calculated using bootstrapping methods (200 replications). ρk and R were estimated as measures of the variation in survival outcomes explained by the regression models. The AJCC, MSTS, and a modified version of the Spanier staging systems showed similar discriminatory abilities and no significant differences in the levels of contrast between different tumor stages across staging systems. Addition of T-category information from each staging system contributed significant prognostic information compared with a Cox proportional hazard regression model consisting only of the presence or absence of metastatic disease as a measure of disease extent. Concordance indices and predictive accuracy for 5-year disease-free survival were not significantly different among the different staging systems either. Similar findings were observed after accounting for other important prognostic variables. Additional studies are necessary to determine performance parameters of each staging system for other types of skeletal sarcoma. Prognostic performance of osteosarcoma staging systems would also be improved by incorporating nonanatomic prognostic variables into staging algorithms.