Clinical features and outcomes of primary bone and soft tissue sarcomas in adolescents and young adults

Teaching Potential of Multidisciplinary Tumor Board Meetings for Orthopedic Residents: Insights From a French Sarcoma Reference Center

Multidisciplinary tumor board meetings (MTBMs) have been established in oncology to improve patient care. While their benefits for patients have been well-documented, there are no previous studies on the teaching opportunities they provide for residents and medical students. This study aimed to examine the teaching provided to residents during MTBM and identify areas for improvement. The study hypothesized that although the primary objective of MTBM is not teaching, they could still contribute to residents' learning. The study focused on the tumors board meeting for bone metastasis and musculoskeletal tumors/sarcoma in a French reference center for musculoskeletal oncology. The composition of the MTBM included specialists from various disciplines, and it convened on a weekly basis to discuss cases. The orthopedic oncology residents (OORs) actively participated in the MTBM as part of their training. A questionnaire was distributed to OORs who had served between 2014 and 2021, and their responses were analyzed. The results showed that the OOR perceived MTBM as interesting, beneficial for their training, and challenging. While opinions were divided on whether MTBM was a suitable place for education, the majority believed it improved their knowledge of different specialties and provided valuable elements applicable to daily practice. They also felt it facilitated future access to MTBs if needed. OORs recommended the rotation as an orthopedic oncology resident to younger residents. Recommendations for improvement included incorporating more dedicated teaching time, active involvement of residents in the learning process, availability of learning materials, and post-MTBM debriefing sessions. The study highlighted the importance of case presentations, public speaking skills, interdisciplinary collaboration, and clinical reasoning observed during MTBM. In conclusion, while not primarily designed for teaching, MTBM offers valuable learning opportunities for residents. Enhancing the teaching experience through dedicated debriefing sessions, resident involvement, and improved support can further optimize their educational impact. Future evaluations are needed to assess the effectiveness of these improvements. This study provides insights into the teaching potential within MTBM and can guide educational initiatives in the field of oncology.

A comparative study between two methods of delivery of chemotherapeutic agent in patients with bone and soft tissue sarcoma of lower extremity

BACKGROUND

We aimed to compare the effects of peripherally inserted central catheters (PICC) and implantable venous access devices (TIVADs) in terms of complications and shoulder function in patients with malignant bone and soft tissue tumors of the lower extremities.

METHODS

We analyzed 65 cases of TIVADs (chest wall) and 65 cases of PICC at the orthopedic department of the Fourth Hospital of Hebei Medical University between June 2019 and December 2021, which were diagnosed with malignant bone tumors or soft tissue tumors of the lower extremities (tumors had to be relatively sensitive to chemotherapy), received regular chemotherapy, with ≥ 14 cycles (42 weeks). The two groups were compared in terms of catheter indwelling time, catheter-related complications, Constant-Murley shoulder function score, and displacement of the position of the catheter end on the catheterization side.

RESULTS

Compared to the PICC group, at six months after catheterization, the TIVADs group reported better outcomes for catheter indwelling time, catheter-related complications, and Constant-Murley score for the catheterization-side shoulder joint (p < 0.05). The TIVADs group also reported less displacement of the catheter end position after 180° abduction of the catheterization-side shoulder joint (p < 0.05).

CONCLUSIONS

Compared with PICC, TIVADs can prolong catheter indwelling time, reduce catheter-related complications, and maintain shoulder joint function, which makes it an ideal venous-access approach when providing chemotherapy to patients with malignant bone and soft tissue tumors of the lower extremities.

Characterization of the tumour microenvironment phenotypes in malignant tissues and pleural effusion from advanced osteoblastic osteosarcoma patients

PURPOSE

Malignant pleural effusion (MPE) is an adverse prognostic factor in patients with osteoblastic osteosarcoma; however, the cellular contexts of MPE are largely unknown.

EXPERIMENTAL DESIGN

We performed single-cell RNA-sequencing (scRNA-seq) on 27 260 cells from seven MPE samples and 91 186 cells from eight osteosarcoma tissues, including one recurrent, one lung metastasis and six primary tumour (PT) samples, to characterize their tumour microenvironment.

RESULTS

Thirteen main cell groups were identified in osteosarcoma tumour and MPE samples. Immune cells dominate the cellular contexts in MPE with more T/NK cells and less osteoclasts compared to PT samples. Of T/NK cells, CD8⁺ GNLY⁺ , CD8⁺ KLRC2⁺ T cells and FCGR3A⁺ NK cells were enriched in MPE but CD4⁺ FOXP3⁺ Tregs were enriched in PT samples. Naïve IGHD⁺ B and immune regulatory IGHA1⁺ B cells were largely identified in MPE, whereas bone metabolism-related CLEC11A⁺ B cells were significantly enriched in osteosarcoma PT. M2-type TAMs, including CLEC11A_TAM, C1QC_TAM and Prolif_TAMs, among myeloid cells were enriched in PT, which may suppress cytotoxicity activities of T cells through multiple ligand-receptor interactions. Mature LAMP3⁺ DCs were transformed from CD1C⁺ DC and CLEC9A⁺ DC sub-clusters when exposure to tumour alloantigens, which may improve T cell cytotoxicity activities on tumour cells under anti-PD-L1 treatments. In further, immune cells from MPE usually present up-regulated glycolysis and down-regulated oxidative phosphorylation and riboflavin metabolism activities compared to those in PT samples.

CONCLUSIONS

Our study provided a novel cellular atlas of MPE and PT in patients with advanced osteosarcoma, which may provide potential therapeutic targets in the future.

Gemcitabine Maintenance Therapy in Patients With Metastasized Soft Tissue Sarcomas

Background

Metastasized soft-tissue sarcomas still pose a significant therapeutic challenge given the limited efficacy of currently available multimodal treatment strategies. Recent progress in molecular characterization of sarcoma subtypes has enabled successful personalized therapy approaches in a minority of selected patients with targetable mutations. However, in the majority of patients with refractory soft tissue sarcomas, long-term survival remains poor.

Methods

We report on three adult patients with various soft tissue sarcomas subjected to Gemcitabine maintenance therapy. Tumor entities included leiomyosarcoma of the pancreas (patient 1), undifferentiated pleomorphic sarcoma of the right femur (patient 2), and peri-aortic leiomyosarcoma (patient 3). Metastatic sites encompassed liver, lung, and bones. All patients received Gemcitabine maintenance therapy until disease progression following prior salvage chemotherapy with Docetaxel and Gemcitabine. Patients were treated outside of clinical trials. Response assessment was based on radiological imaging.

Results

In response to salvage chemotherapy with Docetaxel and Gemcitabine, one patient exhibited a partial remission, and two patients showed stable disease. Patient 1 exhibited stable disease for 6 months during Gemcitabine maintenance therapy before suffering rapid progression of hepatic metastases. Patient 2 underwent 21 months of Gemcitabine maintenance therapy, which was discontinued after progressive pulmonary metastases were detected. Patient 3 is still being treated with Gemcitabine maintenance therapy. Remarkably, owing to significant chemotherapy-associated hematotoxicity, the dose of Gemcitabine dose was reduced by two-thirds. Nevertheless, stable disease with constant pulmonary metastases has been maintained in this patient for 14 months.

Conclusions

Gemcitabine maintenance therapy following prior Docetaxel and Gemcitabine chemotherapy is manageable and reveals potential benefits for patients with aggressive metastasized soft tissue sarcomas. Prospective trials evaluating Gemcitabine maintenance therapy are encouraged.

Development and evaluation of machine learning models based on X-ray radiomics for the classification and differentiation of malignant and benign bone tumors

OBJECTIVES

To develop and validate machine learning models to distinguish between benign and malignant bone lesions and compare the performance to radiologists.

METHODS

In 880 patients (age 33.1 ± 19.4 years, 395 women) diagnosed with malignant (n = 213, 24.2%) or benign (n = 667, 75.8%) primary bone tumors, preoperative radiographs were obtained, and the diagnosis was established using histopathology. Data was split 70%/15%/15% for training, validation, and internal testing. Additionally, 96 patients from another institution were obtained for external testing. Machine learning models were developed and validated using radiomic features and demographic information. The performance of each model was evaluated on the test sets for accuracy, area under the curve (AUC) from receiver operating characteristics, sensitivity, and specificity. For comparison, the external test set was evaluated by two radiology residents and two radiologists who specialized in musculoskeletal tumor imaging.

RESULTS

The best machine learning model was based on an artificial neural network (ANN) combining both radiomic and demographic information achieving 80% and 75% accuracy at 75% and 90% sensitivity with 0.79 and 0.90 AUC on the internal and external test set, respectively. In comparison, the radiology residents achieved 71% and 65% accuracy at 61% and 35% sensitivity while the radiologists specialized in musculoskeletal tumor imaging achieved an 84% and 83% accuracy at 90% and 81% sensitivity, respectively.

CONCLUSIONS

An ANN combining radiomic features and demographic information showed the best performance in distinguishing between benign and malignant bone lesions. The model showed lower accuracy compared to specialized radiologists, while accuracy was higher or similar compared to residents.

KEY POINTS

• The developed machine learning model could differentiate benign from malignant bone tumors using radiography with an AUC of 0.90 on the external test set. • Machine learning models that used radiomic features or demographic information alone performed worse than those that used both radiomic features and demographic information as input, highlighting the importance of building comprehensive machine learning models. • An artificial neural network that combined both radiomic and demographic information achieved the best performance and its performance was compared to radiology readers on an external test set.

Oncological Outcomes in Patients with Appendicular Myxofibrosarcomas: A Retrospective Study

BACKGROUND

Myxofibrosarcoma (MFS) is notorious for its infiltrative growth pattern, making wide excisions difficult to achieve. Our objective was to assess the impact of surgical margins and other factors that affected rates of local recurrence (LR), distant metastasis (DM), and overall survival (OS) of individuals undergoing resection for MFS.

METHODS

We retrospectively reviewed the medical records of 209 patients with appendicular soft tissue sarcomas between January 2012 and June 2018. Of these, 29 patients (14%) were diagnosed with myxofibrosarcoma. These patients underwent a total of 33 resections. The pathological analyses were conducted by an experienced musculoskeletal (MSK) pathologist. Demographics data, operative details, adjuvant therapy, and oncological outcomes were assessed.

RESULTS

Of the 29 patients (33 resections), the overall LR rate was 24% (7/29) and the 2-year LR rate was 17% (5/29). Factors associated with negative oncological outcomes were as follows: tumor size ≤10 cm (2-year local recurrence-free rates (LRFRs), 65%; 95% CI, 44-86%; p=0.02) and positive surgical margins grouped with surgical margins ≤0.1 cm (hazard ratio (HR), 11.74; 95% CI, 1.41-97.74; p=0.02). Chemotherapy and radiotherapy together increased the 2-year LRFR (LRFR, 100%; 95% CI, 100%, p=0.001). Two-year DM and OS rates were 15% and 79%, respectively. Female gender was a predictor of distant metastasis. Local recurrence had a negative impact on overall survival. Intraoperative analysis of resection margin accuracy was 75% (12/16) when non-MSK pathologists were involved but 100% accurate (12/12) when analyzed by an MSK pathologist.

CONCLUSION

Myxofibrosarcomas showed high LR rates after treatment. Close margins (≤0.1 cm) should be considered as a risk factor for LR, and LR is associated with negative overall survival. Neoadjuvant therapy in terms of combined chemotherapy and radiation therapy associates with decreased LR rates. If intraoperative assessment of margins is to be done, it should be performed by an experienced MSK pathologist.

Development of a Novel Immune Infiltration-Related ceRNA Network and Prognostic Model for Sarcoma

Due to the rarity and heterogeneity, it is challenging to explore and develop new therapeutic targets for patients with sarcoma. Recently, immune cell infiltration in the tumor microenvironment (TME) was widely studied, which provided a novel potential approach for cancer treatment. The competing endogenous RNA (ceRNA) regulatory network has been reported as a critical molecular mechanism of tumor development. However, the role of the ceRNA regulatory network in the TME of sarcoma remains unclear. In this study, gene expression data and clinical information were obtained from The Cancer Genome Atlas (TCGA) sarcoma datasets, and an immune infiltration-related ceRNA network was constructed, which comprised 14 lncRNAs, 13 miRNAs, and 23 mRNAs. Afterward, we constructed an immune infiltration-related risk score model based on the expression of IRF1, MFNG, hsa-miR-940, and hsa-miR-378a-5p, presenting a promising performance in predicting the prognosis of patients with sarcoma.

Surgical management of sarcoma in adolescent and young adult patients

Objective

To examine the clinical features and outcomes of adolescent and young adult sarcoma patients who underwent surgical management and clarify important factors associated with prognosis. We reviewed 18 young adult sarcoma patients sarcoma patients treated surgically in our hospital. The tumor site, histology, grade, stage, and American Society of Anesthesiologists-Physical Status before surgery, operation time, intraoperative blood loss, complications, surgical margin, local recurrence, metastasis, and outcomes were investigated. The 3-year survival rate was also calculated. We compared survival based on age, grade, and surveyed features of poor outcome cases.

Results

The 3-year survival rate was 61.3%. There was no significant difference in survival based on age, grade, operation time, or intraoperative blood loss. Three of five patients who died of the disease had stage ≥ IV at diagnosis. All patients with R1 surgical margins developed recurrence and all those with an American Society of Anesthesiologists-Physical Status ≥ 2 died. Patients with late-stage sarcomas, R1 tumor margin, or high American Society of Anesthesiologists-Physical Status score had poor prognoses. To achieve a favorable outcome in adolescent and young adult sarcoma patients, early detection and obtaining R0 ≥ surgical margin are essential.