Clinical Efficacy of Carbon Ion Radiotherapy for Unresectable Chondrosarcomas

BACKGROUND

Carbon ion radiotherapy has precise dose distribution and high biological effectiveness and is likely a promising therapy for patients with sarcomas. We evaluated the outcomes of carbon ion radiotherapy in patients with unresectable chondrosarcomas.

PATIENTS AND METHODS

A retrospective analysis of 75 tumors in 73 patients treated with carbon ion radiotherapy was performed. There were 26 spinal, 38 pelvic, and 11 other types of tumors. Seventy conventional and five dedifferentiated chondrosarcomas were treated in 69 and four patients, respectively.

RESULTS

The median follow-up period was 49.4 (range=6.4-146.4) months. The 5-year local control, overall survival, and disease-free survival rates were 53%, 53%, and 34%, respectively. By multivariate analysis, tumor volume and histological grade were significantly related to overall and disease-free survival. Five patients required surgical intervention because of adverse events in the bones.

CONCLUSION

Carbon ion radiotherapy might be a treatment option for unresectable chondrosarcoma.

Reduced argininosuccinate synthetase expression in refractory sarcomas: Impacts on therapeutic potential and drug resistance

Background

Treating drug-resistant sarcomas remains a major challenge. The present study aimed to identify a novel therapy for drug-resistant sarcomas based on metabolic errors involving argininosuccinate synthetase1 (ASS1).

Results

ASS1 expression was reduced in Dox-resistant sarcoma cells. Immunohistochemistry and real-time PCR showed an inverse correlation between ASS1 and P-gp expressions. The inhibition of cellular proliferation with G1-arrest was shown to lead to autophagy with arginine deprivation. In addition, the combination of an autophagy inhibitor plus arginine deprivation was more effective than arginine deprivation alone. In cells with suppressed ASS1 expression, P-gp expression was upregulated as compared to that in negative controls.

Discussion

These results indicate that the reduced ASS1 expression in Dox-resistant sarcomas may contribute to drug resistance in association with the expression of P-gp. ASS1 deficiency is a potential target for novel drug therapies. The combination of arginine-deprivation therapy and an autophagy inhibitor may have anti-tumor effects in refractory sarcomas.

Methods

We assessed the expressions of ASS1 and P-glycoprotein (P-gp) in clinical specimens and cell lines of osteosarcoma (KHOS), doxorubicin (Dox)-resistant osteosarcoma (KHOS_R2), epithelioid sarcomas (ES-X and VAESBJ) and alveolar soft part sarcoma (ASPS-KY). Each cell line was cultured in arginine-containing and arginine-free media. Cell growth was assessed using an XTT assay and flow cytometry. We analyzed the induction of autophagy in arginine-free medium. Moreover, we assessed the expression of P-gp after suppressing ASS1 in Dox-sensitive cells (MCF-7 and KHOS) and after transfecting ASS1 into Dox-resistant cells (ES-X, VAESBJ, ASPS-KY and KHOS_R2).

Immunological status of peripheral blood is associated with prognosis in patients with bone and soft-tissue sarcoma

Immune-checkpoint inhibitors have shown promising antitumor effects against certain types of cancer. However, specific immune-checkpoint inhibitors for patients with sarcoma have yet to be identified, whereas the immunological status of peripheral blood in patients with bone sarcoma and soft-tissue sarcoma (STS) remains unknown. In addition, it is unclear whether the immunological status from the peripheral blood could be used as a prognostic indicator. Therefore, the present study aimed to clarify the immunological status of peripheral blood samples derived from patients with bone sarcoma and STS. Immune monitoring was performed using the peripheral blood samples of 61 patients with no metastasis of high-grade sarcoma. A total of 25 patients with metastatic sarcoma were used for comparison. A total of 41 immune cell subsets were analyzed using multicolor-flow cytometry. The patients that did not have metastasis demonstrated higher quantities of monocytic myeloid-derived suppressor cells (M-MDSCs) and T cell immunoglobulin and mucin domain-3 (Tim-3)⁺ CD8⁺ T cells, which were significantly associated with poor disease-free survival (DFS) time, while higher quantities of NKG2D⁺ CD8⁺ T cells were significantly associated with improved DFS time. Multivariate Cox regression analysis demonstrated that the number of Tim-3⁺ CD8⁺ T cells was associated with lower DFS time. A significant association was also found between the number of M-MDSCs and progression-free survival (PFS) time in patients with metastasis. The results suggested the occurrence of immune surveillance, which indicated that the host immune reaction against cancer existed in patients with bone sarcoma and STS. Notably, a high number of M-MDSCs was associated with both DFS and PFS time, suggesting a strong prognostic value. The data suggested that the immune status of peripheral blood was associated with the prognosis in patients with sarcoma, as previously reported in patients with other cancer types. In summary, the results may assist with the development of novel strategies for sarcoma treatment, based on the use of biomarkers or immunotherapy.

Pediatric Sarcoma Patients with Worse Physical Function but Better Peer Relationships and Depressive Symptoms than U.S. Pediatric Population as Measured by PROMIS®

Background

Pediatric patients with sarcomas are at risk of poor quality of life outcomes. The National Institutes of Health (NIH)-funded Patient-reported Outcomes Measurement Information System (PROMIS®) improves our ability to capture patient-reported outcomes. Do physical function, social, and mental health PROMIS outcomes for pediatric patients with non-metastatic malignant sarcomas differ from the U.S. pediatric population?

Methods

Six pediatric PROMIS short forms were collected for patient visits to orthopedic oncology at a tertiary referral center from September 1, 2016, to March 31, 2017. Mean T-scores differed from the reference population by a one-sample t-test.

Results

Of the 30 eligible patients, five had soft-tissue sarcomas and 25 (83%) had bone sarcomas. The mean age of the cohort was 13 years (5-17). The study cohort had a mean physical function T-score of 39.8 (SD 9.8), which was worse than the reference population. In contrast, the mean peer relationship T-score of 54.3 (SD 8.8) and mean depression T-score of 42.0 (SD 9.1) were better than the reference population.

Conclusions

Pediatric patients with non-metastatic sarcomas had a worse physical function but a better peer relationship and depression scores than the U.S. PROMIS reference population. Ceiling and flooring effects were reported. The level of evidence was III.

Surgical Triumph Over Metatarsal Osteosarcoma: A Rare Case Report Revealing Diagnostic Challenges and Successful Management

Osteosarcoma of the foot is exceedingly uncommon, and as a result, very little is known about patient and tumor characteristics. In addition, the prognosis may be grim due to delayed presentation and misdiagnosis. A delayed diagnosis of osteosarcoma, regardless of location, may not only reduce long-term survival but also modify the treatment plan, resulting in less favorable functional and cosmetic outcomes. Here we report the diagnostic and therapeutic challenges associated with chondroblastic osteosarcoma involving the metatarsal bone of the foot in a 47-year-old woman treated with wide local excision with right second metatarsectomy and non-vascularized fibular graft reconstruction along with adjuvant chemotherapy.

Metastatic Cardiac Tumor Presenting as an Anteroseptal ST-Segment Elevation Myocardial Infarction in a Young Male

In the appropriate clinical context, ST-segment elevation on electrocardiogram (ECG) necessitates prompt evaluation for coronary artery occlusion requiring reperfusion with percutaneous coronary intervention. Conversely, the etiology of ST-segment elevation may be representative of an alternative diagnosis other than myocardial infarction. We report the case of a patient with a history of primary bone sarcoma who presented for further evaluation of a large pericardial effusion identified on an outpatient echocardiogram and was found to have ST-segment elevation on ECG in the absence of any cardiopulmonary symptoms. The ECG abnormalities were attributed to a likely persistent current of injury resulting from a mass in the interventricular septum, likely representative of a metastatic lesion of his known malignancy. This case highlights the importance of maintaining a broad differential for ST-segment elevation, particularly in patients without symptoms of angina and those with a history of aggressive or relapsing cancer to minimize the morbidity and mortality of invasive procedures.