Diagnosis of chondrosarcoma in a noninvasive way using volatile organic compounds in exhaled breath: a pilot study.

Aim: Aim of this explorative pilot study was to evaluate the capability of an electronic nose (aeoNose, the eNose Company) to classify healthy individuals and patients with chondrosarcoma, based on their volatile organic compound profiles in exhaled breath. Materials & methods: Fifty-seven patients (25 healthy controls, 24 chondrosarcoma and 8 different benign lesions) were included in the study from 2018 to 2023. An artificial neural network was used as classifier. Results: The developed model had a sensitivity of 75%, and a specificity of 65% with an AUC of 0.66. Conclusion: Results show that there is not enough evidence to include the aeoNose as diagnostic biomarker for chondrosarcoma in daily practice. However, the aeoNose might play an additional role alongside MRI, in questionable chondrosarcoma cases.

Noninvasive detection of soft tissue sarcoma using volatile organic compounds in exhaled breath: a pilot study.

Aim: The aim of this pilot study was to assess whether an electronic nose can detect patients with soft tissue sarcoma (STS) based on volatile organic compound profiles in exhaled breath. Patients & methods: In this cross-sectional pilot study, patients with primary STS and healthy controls, matched on sex and age, were included for breath analysis. Machine learning techniques were used to develop the best-fitting model. Results: Fifty-nine breath samples were collected (29 STS and 30 control) from March 2018 to March 2022. The final model yielded a c-statistic of 0.85 with a sensitivity of 83% and specificity of 60%. Conclusion: This study suggests that exhaled volatile organic compound analysis could serve as a noninvasive diagnostic biomarker for the detection of STS with a good performance.

Diagnosing soft tissue sarcoma (STS) among the large number of benign soft tissue tumors is challenging. There is a serious need for a novel and easy tool that could accurately detect patients with STS. This study aimed to assess how well an easy-to-use electronic nose could differentiate between patients with STS and those without STS based on their exhaled breath. This is the first pilot study to reveal that an electronic nose could serve as a diagnostic tool for the detection of STS with a good performance. Future studies are needed to validate the findings in larger cohorts.

As simple as it sounds? The treatment of simple bone cysts in the proximal femur in children and adolescents: Retrospective multicenter EPOS study of 74 patients.

Purpose: Simple bone cysts are among the most prevalent benign cystic tumor-like lesions in children. Proximal femoral simple bone cysts may require specific treatment because of increased fracture risk. With limited literature available on this specific localization, consensus regarding optimal treatment is lacking. We present a large international multicenter retrospective cohort study on proximal femoral simple bone cysts. Methods: All consecutive pediatric patients with proximal femoral simple bone cyst from 10 tertiary referral centers for musculoskeletal oncology were included (2000-2021). Demographics, primary treatment, complications, and re-operations were evaluated. Primary outcomes were time until full weight-bearing and failure-free survival. Results: Overall, 74 simple bone cyst patients were included (median age 9 years (range = 2-16), 56 (76%) male). Median follow-up was 2.9 years (range = 0.5-21). Index procedure was watchful waiting (n = 6), percutaneous procedure (n = 12), open procedure (n = 50), or osteosynthesis alone (n = 6). Median time until full weight-bearing was 8 weeks (95% confidence interval = 0.1-15.9) for watchful waiting, 9.5 (95% confidence interval = 3.7-15.3) for percutaneous procedure, 11 (95% confidence interval = -0.7 to 13.7) for open procedure, and 6.5 (95% confidence interval = 5.9-16.1) for osteosynthesis alone (p = 0.58). Failure rates were 33%, 58%, 29%, and 0%, respectively (p = 0.069). Overall failure-free survival at 1, 2, and 5 years was 77.8% (95% confidence interval = 68.2-87.4), 69.5% (95% confidence interval = 58.5-80.5), and 62.0% (95% confidence interval = 47.9-76.1), respectively. Conclusion: A preferred treatment for proximal femoral simple bone cysts remains unclear, with comparable failure rates and times until full weight-bearing. Watchful waiting may be successful in certain cases. If not feasible, osteosynthesis alone can be considered. Treatment goals should be cyst control, minimizing complications and swift return to normal activities. Therefore, an individualized balance should be made between undertreatment, with potentially higher complication risks versus overtreatment, resulting in possible larger interventions and accompanying complications. Level of evidence: Level IV, retrospective multicentre study.

Surgery for metachronous metastasis of soft tissue sarcoma - A magnitude of benefit analysis using propensity score methods.

INTRODUCTION: Metastasectomy is hypothesised to improve OS in metastatic STS, but evidence in favour of this approach derives from non-controlled single-arm cohorts affected by selection bias. The objective was to quantify the effect of metastasectomy vs. non-surgical management on overall survival (OS) in patients with metachronous metastases from extremity- and trunk soft tissue sarcoma (STS). MATERIALS AND METHODS: From a population of 1578 STS patients, 135 patients who underwent surgery for localised STS at two European centres between 1998 and 2015 and developed metachronous STS metastases were included. Propensity score analyses with inverse-probability-of-treatment-weights (IPTW) and landmark analyses were performed to control for selection and immortal time bias, respectively. RESULTS: OS was significantly longer in the 68 patients undergoing metastasectomy than in the 67 patients who were treated non-invasively for their metastasis (10-year OS: 23% vs. 4%; hazard ratio (HR) = 0.34, 95% CI: 0.22-0.53, p < 0.0001). This association prevailed after IPTW-weighting of the data to control for the higher prevalence of favourable prognostic factors in the surgery group (adjusted 10-year OS: 17% vs. 3%, log-rank p < 0.0001; HR = 0.33, 95% CI: 0.20-0.52, p < 0.0001). Five-year OS estimates were 27.8% in patients who had and 14.5% in patients who had not undergone metastasectomy within the first 3 months after diagnosis of a metastasis (p < 0.0001). CONCLUSION: In this observational bi-centre study, metastasectomy was associated with prolonged survival in patients with metachronous STS metastases. In the absence of randomized studies, our results indicate that metastasectomy should be considered as an important treatment option for metachronous STS metastases.

Outcome of Long-Term Bisphosphonate Therapy in McCune-Albright Syndrome and Polyostotic Fibrous Dysplasia.

McCune-Albright syndrome (MAS) is a rare bone disorder characterized by fibrous dysplasia (FD), endocrinopathies, and café-au-lait patches. FD patients have been shown to respond favorably to treatment with bisphosphonates, but data are scarce in the more severe polyostotic form (PFD), including MAS, and factors determining treatment outcome are not known, particularly in the long-term. We evaluated the biochemical (bone turnover markers [BTMs]) and clinical (pain reduction) outcome of bisphosphonate therapy in 11 patients with MAS and 30 patients with PFD: median duration of treatment 6 years (range, 2 to 25 years). Prognostic factors for treatment outcome were identified in both groups. Patients with MAS were younger at diagnosis (p = 0.001), all had precocious puberty, and four (36%) had additional growth hormone (GH) excess associated with severe craniofacial FD. Extent of skeletal disease was more severe in MAS compared to PFD. MAS patients had higher serum alkaline phosphatase (ALP) concentrations (p = 0.005), higher skeletal burden scores (p < 0.001), and more fractures (p = 0.021). MAS patients had also higher levels of FGF-23 (p = 0.008) and higher prevalence of hypophosphatemia (p = 0.013). Twenty-four of 30 PFD patients (80%) demonstrated a complete clinical and biochemical response within a year of starting treatment (p = 0.015), compared to only four of 11 MAS patients (36%). There were no nonresponders. In the whole group, FGF-23, total ALP, P1NP, and CTX positively correlated with skeletal burden scores (all p ≤ 0.001), which was the only significant risk factor for an incomplete response to bisphosphonate therapy (p < 0.01). Our data suggest a beneficial and safe outcome of long-term bisphosphonate therapy in the majority of patients with PFD, although response to therapy was limited by the higher skeletal disease burden in MAS patients. In the PFD/MAS population studied, the only identified prognostic factor that influenced the outcome of bisphosphonate therapy was a high skeletal burden score. © 2016 American Society for Bone and Mineral Research.