Background Undifferentiated pleomorphic sarcoma (UPS) is a sarcoma with a poor prognosis. A clinical trial, SARC028, revealed that treatment with anti-PD-1 drugs was effective against UPS. Studies have reported that UPS expresses PD-L1, sometimes strongly (≥ 50%). However, the mechanism of PD-L1 expression in UPS has remained unclear. CKLF-like MARVEL transmembrane domain containing 6 (CMTM6) was identified as a novel regulator of PD-L1 expression. The positive relationship between PD-L1 and CMTM6 has been reported in several studies. The aim of this study was thus to examine CMTM6 expression in UPS and evaluate the relationship between PD-L1 and CMTM6 in this disease. Materials and methods Fifty-one primary UPS samples were subjected to CMTM6 and PD-L1 immunostaining. CMTM6 expression was assessed using proportion and intensity scores. CMTM6 gene copy number was also evaluated using a real-time PCR-based copy number assay. We also analyzed the mRNA expression and copy number variation of PD-L1 and CMTM6 in The Cancer Genome Atlas (TCGA) data. Results TCGA data indicated that the mRNAs encoded by genes located around 3p22 were coexpressed with CMTM6 mRNA in UPS. Both proportion and intensity scores of CMTM6 positively correlated with strong PD-L1 expression (≥ 50%) (both p = 0.023). CMTM6 copy number gain increased CMTM6 expression. Patients with UPS with a high CMTM6 intensity score had a worse prognosis for overall survival. Conclusions UPS showed variation in CMTM6 copy number and CMTM6 expression. CMTM6 expression was significantly correlated with PD-L1 expression, especially with strong PD-L1 expression.

Background: The distal femur is a common site of bone tumors. After surgical resection, prosthetic replacement is a major reconstruction method. We aimed to elucidate the long-term outcomes of the Kyocera Modular Limb Salvage (KMLS) systems after resection of tumors in the distal part of the femur. Methods: Between 1998 and 2014, 125 patients were treated at 14 institutions. There were 59 males and 66 females, with a mean age of 35 years. The mean follow-up period was 132 months. Results: There had been 65 additional surgeries, including 56 revisions and 9 amputations: 15 for aseptic loosening, 14 for stem breakage, 13 for deep infection, 13 for rotator-hinge bushing failure, 5 for local recurrence, and 5 for others. Implant survival rates at 10 and 15 years were 58.5% and 39.4%. The cumulative incidence of 15-year revision for femoral stem breakage was 31.7% in patients with cementless fixation. The 15-year cumulative incidence of revision for aseptic loosening was 19.8% in patients with cement fixation. Conclusions: KMLS systems represent a reliable system with long-term results. Stem breakage should be considered in patients with cementless and/or smaller femoral stem sizes. Aseptic loosening should be considered in patients with cement systems after 10 years.

Although there is no evidence from prospective randomized controlled trials to support this practice, pulmonary metastases of sarcomas are often treated surgically if they are resectable. The purpose of this retrospective study was to evaluate the prognostic factors and outcome of pulmonary metastasectomy (PM) for soft tissue sarcomas (STSs) arising in the trunk wall and extremities in 66 consecutive patients. Prognostic factors associated with disease-specific survival after PM were evaluated using univariate and multivariate analyses. The patients included 38 men and 28 women, with a median age of 49 years. The median disease-specific survival after PM was 48 months, and the 5-year survival rate was 45%. No major perioperative complications occurred. Disease-free interval (<12 months), size of largest lung lesion (≥20 mm), and non-curative resection were independent prognostic factors in multivariate analysis. PM was effective in selected patients with pulmonary metastases from STSs arising in the trunk wall and extremities. Disease-free interval, maximum size of metastases, and resectability were identified as prognostic factors.

Case: A 45-year-old woman with severe back pain underwent percutaneous curettage and balloon kyphoplasty (BKP) of a lesion believed to be aneurysmal bone cyst. Three months after BKP, local recurrence was observed, and the histological diagnosis was revised to malignant tumor. Thus, we performed a total en bloc spondylectomy, and the L3 vertebral body was resected. She was reconstructed by titanium expandable cage, rod, and pedicle screws. We observed viable tumor cells and foreign body reaction adjacent to the polymethylmethacrylate cement, carrying no bone necrosis. Conclusions: The long-term durability and safety of BKP for metastatic spine disease should be further clarified.

A vessel sealing system can help reduce the risk of postoperative complications after tumour resection in the medial thigh

Rationale: Complications of rod migration into the occipital bone after upper cervical fusion are very rare. No other cases have been reported, especially when associated with destructive spondyloarthropathy (DSA). The purpose of this case report is to remind clinicians of the risk of rod migration in cervical spine surgery in patients with DSA and to provide information on its causes, countermeasures, and treatment. Patient concern: This case report presents the clinical course of a 61-year-old female patient with chronic kidney disease that required hemodialysis. Diagnosis, intervention, outcomes: The patient was diagnosed DSA involving the cervical spine. Initial treatment involved a halo vest, followed by anterior cervical corpectomy and fusion spanning from C5 to Th1. However, subsequent complications, including C5 fractures, kyphotic cervical alignment, and rod migration into the occipital bone, lead to multistage surgical interventions. This case highlights the challenges in managing DSA, the significance of optimal fixation strategies, and the importance of accounting for potential alignment changes. Conclusion: The effective management of occipital bone erosion after posterior cervical spine surgery for destructive spondyloarthropathy necessitates meticulous fixation planning, proactive rod length adjustment, preoperative assessment of the occipital position, and consideration of the compensatory upper cervical range of motion to prevent migration-related issues.