Search

To characterize the imaging features of patients with pathologically confirmed intraosseous schwannoma (IOS), institutional pathology and imaging databases were searched for IOS cases over a period of 17 years. A musculoskeletal radiologist evaluated all imaging studies. Additionally, a literature search was performed to identify IOS cases that had imaging findings of at least two modalities. Six patients (one female, five males, mean age of 50 ± 14 years) with IOS were identified, with all lesions localized to the lumbosacral region. Radiographic imaging was available in four patients, while all patients underwent CT and MR imaging. Radiographs depicted lytic lesions, and CT depicted heterogeneous expansile lesions with centrally hypodense areas and peripheral sclerosis. All cases involved extra-osseous extension, producing a mass effect on adjacent soft tissues and nerve roots. On MRI, the neoplasms displayed iso- to- slightly- low signal intensity on T1-weighted images and hyperintense signal intensity on T2-weighted images with heterogeneous enhancement. The literature review resulted in 102 IOS cases, which to the best of our knowledge, is the largest review on IOS, and the imaging findings of the previously published cases were the same as our cases. IOSs are rare benign neoplasms that should be considered in the differential diagnosis of well-defined expansile lytic lesions with sclerotic borders. This is particularly important in middle-aged adults with mandibular, sacral, or vertebral body mass.

The 2020 release of the WHO Classification of Soft Tissue and Bone Tumors, 5th edition, contains several changes driven by new knowledge in the field. These include reclassification of some entities, refinement of risk classification systems, and the inclusion of novel disease processes, many of which are driven by recurrent gene fusions. The most notable changes are described here.

Background Adoptive cellular therapy (ACT) is a promising treatment for synovial sarcoma (SS) with reported response rates of over 50%. However, more work is needed to obtain deeper and more durable responses. SS has a ‘cold’ tumor immune microenvironment with low levels of major histocompatibility complex (MHC) expression and few T-cell infiltrates, which could represent a barrier toward successful treatment with ACT. We previously demonstrated that both MHC expression and T-cell infiltration can be increased using systemic interferon gamma (IFN-γ), which could improve the efficacy of ACT for SS.Case presentation We launched a phase I trial incorporating four weekly doses of IFN-γ in an ACT regimen of high-dose cyclophosphamide (HD Cy), NY-ESO-1-specific T cells, and postinfusion low-dose interleukin (IL)-2. Two patients were treated. While one patient had significant tumor regression and resultant clinical benefit, the other patient suffered a fatal histiocytic myocarditis. Therefore, this cohort was terminated for safety concerns.Conclusion We describe a new and serious toxicity of immunotherapy from IFN-γ combined with HD Cy-based lymphodepletion and low-dose IL-2. While IFN-γ should not be used concurrently with HD Cy or with low dose IL-2, IFN-γ may still be important in sensitizing SS for ACT. Future studies should avoid using IFN-γ during the immediate period before/after cell infusion.Trial registration numbers NCT04177021, NCT01957709, and NCT03063632.