Bone Cancer

P1/2, N=12, Active, not recruiting, Memorial Sloan Kettering Cancer Center | Recruiting --> Active, not recruiting | N=46 --> 12

Stromal myeloid cells showed increased CD47 and PD-1 expression. Our study identified distinct epigenetic profiles in sacral chordomas, which were associated with recurrence, and revealed expression of checkpoint markers TIM3, CD47 and PD-1, warranting further investigation through functional validation.

P=N/A, N=30, Not yet recruiting, Nantes University Hospital

P2, N=20, Not yet recruiting, Merck Healthcare KGaA, Darmstadt, Germany, an affiliate of Merck KGaA, Darmstadt, Germany

The tumor mutational burden was low overall, varied between patients and timepoints, and tended to be higher in recurrent cases. Quantitative nuclear morphometry, integrated with immunophenotyping and genomic profiling, captures recurrence-associated phenotypic remodeling in chordoma and may provide a quantitative framework for future digital pathology or AI approaches, pending validation in larger cohorts.

Although representing just 5% of all identified factors, these appeared in 69% of the included studies, highlighting their prominence in the literature. Apart from the well-known osteoclastogenesis factor CSF1, inflammatory cytokines (TNF-α and IL-1β) and monocyte-macrophage lineage makers (CD68, CD163) are signalling pathways key to TGCT disease progression and associated bone destruction.

Recent examples include spindle cell rhabdomyosarcomas with TFCP2 fusions, keratin-positive giant-cell rich tumors with HMGA2::NCOR2 fusions, NR1D1- rearranged sarcomas, malignant epithelioid neoplasms with FET::CREB fusions, and the very recently described ossifying spindled and epithelioid tumors (OSET). This review will address the unique clinical, histologic, and immunophenotypic characteristics of these rare neoplasms and provide practical considerations for molecular testing in challenging cases of keratin-positive mesenchymal neoplasia.

These studies indicate that GCTB not only induces osteoclasts, but also possesses activity that inhibits bone formation.

P3, N=123, Active, not recruiting, Deciphera Pharmaceuticals, LLC | Trial completion date: Jul 2026 --> Jul 2028

P=N/A, N=72, Recruiting, Mayo Clinic | Trial completion date: Aug 2028 --> Aug 2031

The remaining patients were alive and well at 16 to 33 months. MPC represents a distinct clinicopathological entity with frequent c-MYC amplification and may benefit from targeted MYC inhibition.

Proteomic analysis revealed that NCC-GCTB16-C1 exhibited properties similar to those of the original tumor tissue. Thus, NCC-GCTB16-C1 provides an in vitro model that faithfully reflects the molecular and phenotypic features of GCTB, offering a valuable tool for mechanistic studies and preclinical drug evaluation.