Giant Cell Tumor of Bone

Differentiating benign intra-articular tumors from SAH remains difficult, particularly among younger and female patient populations with acute presentations of TGCT which, as observed in the present study, may be explained by histopathologic evidence of tumor pedicle torsion and resultant necrosis. MRI can be valuable in identifying intra-articular lesions given that clinical and laboratory findings are frequently equivocal. The proposed diagnostic algorithm offers a framework for identifying cases where preoperative MRI may be beneficial, though it requires validation in larger studies.

Overall, our findings indicate that PMMRDGs represent a distinct type of IDH-wildtype gliomas with potential for long-term survival likely driven by immune activation.

P2, N=798, Active, not recruiting, National Cancer Institute (NCI) | Trial primary completion date: May 2027 --> May 2026

Ferroptosis, immune, and proliferation markers differ significantly between TGCT subtypes and recurrence status. The ACSL4+CD8 signature shows excellent potential for subtype differentiation, while the Ki-67+CSF1R+tumor diameter index is a strong recurrence predictor. These exploratory findings support targeted biomarker use in TGCT management, though external validation in larger, prospective cohorts is required.

A central shared mechanism is the dysregulation of the NFκB pathway, which in PDB leads to increased osteoclast differentiation, and in cancer fosters a pro-inflammatory environment that promotes tumorigenesis. Understanding how altered bone remodelling intersects with cancer‑related signalling highlights shared molecular vulnerabilities that could be exploited therapeutically, and provides a framework for future mechanistic and translational studies in PDB‑associated cancer.

SGCs may represent a terminally differentiated tumor cell variant of ccRCC associated with localized TGF-β-related immunosuppressive niche formation, potentially contributing to tumor immune evasion and progression.

P=N/A, N=70, Recruiting, St. Anne's University Hospital Brno, Czech Republic

The case highlights the importance of comprehensive clinicoradiological and histopathological correlation, supplemented by immunohistochemistry, for accurate diagnosis, particularly in atypical presentations. Considering the potential for aggressive behavior and recurrence, appropriate surgical management and long-term follow-up are essential for optimal outcomes.

The disappearance of the H3F3A mutation may be associated with malignant transformation in GCTB, whereas our findings suggest that it does not correspond to the tumor's morphological or biological characteristics.

The histone H3 variant (H3-3A p.G35W) detected in our patient has not been previously characterised in tectal plate gliomas, rendering it an unclear predictor of tumour behaviour. In this case study, we discuss the importance of methylation profiling and the potential implications of H3 G34-mutant gliomas.

An arthroscopic examination revealed numerous white synovial, chondromate-like tissues under the articular capsule, and D-TGCT was diagnosed based on the histopathological results. One year after the surgery, the patient had good functional recovery and no tumor recurrence.

P2, N=818, Active, not recruiting, National Cancer Institute (NCI) | Trial completion date: May 2026 --> May 2027 | Trial primary completion date: May 2026 --> May 2027