-rearranged B-cell ALL with extramedullary lineage switch to AML following CD19-targeted therapy.

Lineage switch (LS) refers to the immunophenotypic transformation of one leukemia lineage to another (ie, lymphoid to myeloid) with retention of baseline genetics. This phenomenon was originally observed in infants with B-lymphoblastic leukemia (B-ALL) with rearrangements following chemotherapy, but is now increasingly being observed as a form of immune escape following targeted therapies among children and adults with B-ALL with and without rearrangements. In this report, we present two cases of adolescents with B-ALL harboring rearrangements (Philadelphia-like phenotype) who developed LS to acute myeloid leukemia following CD19 targeted therapy.

F-FDG-PET/MR imaging to monitor disease activity in large vessel vasculitis.

Disease-monitoring in large vessel vasculitis (LVV) is challenging. Simultaneous F-fluorodeoxyglucose positron emission tomography with magnetic resonance imaging (PET/MRI) provides functional assessment of vascular inflammation alongside high-definition structural imaging with a relatively low burden of radiation exposure. Here, we investigate the ability of PET/MRI to monitor LVV disease activity longitudinally in a prospective cohort of patients with active LVV.

Corrigendum to "Erdheim-Chester disease with tendon and muscle involvement: Reports of a rare presentation" [Radiology Case Reports 19 (2024) 1866-1871].

[This corrects the article DOI: 10.1016/j.radcr.

Erdheim-Chester disease with tendon and muscle involvement: Reports of a rare presentation.

Erdheim-Chester disease (ECD) is a rare histiocytic disease that affects multiple systems in the body. While it typically targets long bones, cardiovascular structures, the retroperitoneum, and the central nervous system, reports of tendon and skeletal muscle involvement are scarce. This review presents 2 cases: a case of ECD involving the left Achilles tendon and left abductor hallucis, as well as an unusual manifestation of ECD in the thigh musculature.

Skeletal involvement in Erdheim-Chester disease: Multimodality imaging features and association with the BRAF mutation.

Objective: The aim of this study was to characterize the distribution of skeletal involvement in Erdheim-Chester disease (ECD) by using radiography, computed tomography (CT), F-FDG positron emission tomography/computed tomography (PET/CT), and bone scans, as well as looking for associations with the BRAF mutation.

Material And Methods: Prospective study of 50 consecutive patients with biopsy-confirmed ECD who had radiographs, CT, F-FDG PET/CT, and Tc-99m MDP bone scans. At least two experienced radiologists with expertise in the relevant imaging studies analyzed the images.