Radiological features of Rosai–Dorfman disease: case series and review of the literature

•We studied the CT and MRI characteristics of Rosai–Dorfman disease. •It is characterized by multifocal involvement, primarily in the head and neck. •CT/MRI show well-defined, irregularly shaped lesions with homogeneous density/signals. •They exhibit progressive enhancement on multiphasic contrast-enhanced scans. •Histopathology is the gold standard and is required for confirmation of diagnosis. Aim To improve the accuracy of diagnosis of Rosai–Dorfman disease (RDD) by summarising the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics. Materials and methods The clinical manifestations, imaging findings, and pathological characteristics of 14 patients with histopathologically confirmed RDD were analysed retrospectively and a literature review was undertaken. Results Of the 14 patients, nine had multiple lesions and five had single lesions. Eight patients had extranodal lesions, while six had mixed-type lesions. In patients with head and neck lesions, plain CT/MRI revealed irregularly shaped, well-defined, homogeneous, and mainly progressive lesions, with marked homogeneous enhancement on multiphasic contrast-enhanced imaging. One patient had dural lesions, one of which iso-intense to grey matter, with patchy hypo-intensity on T2-weighted imaging, meningeal tail signs, and characteristic crabfoot-like enhancement. Three patients with skeletal system involvement exhibited osteolytic bone destruction without sclerosis at the edges, associated soft-tissue masses, or periosteal reactions. Two patients had well-defined subcutaneous lesions, inhomogeneous density, and progressive parenchymal enhancement on contrast-enhanced CT. One patient had multiple intestinal lesions with inhomogeneous nodular thickening of the blind ascending colon and ileum, with marked and progressive enhancement. Conclusion RDD involvement is mainly multifocal, primarily in the head and neck regions. Plain CT/MRI revealed well-defined, irregularly shaped lesions with homogeneous density/signal, with marked and progressive enhancement on multiphasic contrast-enhanced imaging; however, histopathology is still required to confirm the diagnosis of RDD. To improve the accuracy of diagnosis of Rosai–Dorfman disease (RDD) by summarising the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics. The clinical manifestations, imaging findings, and pathological characteristics of 14 patients with histopathologically confirmed RDD were analysed retrospectively and a literature review was undertaken. Of the 14 patients, nine had multiple lesions and five had single lesions. Eight patients had extranodal lesions, while six had mixed-type lesions. In patients with head and neck lesions, plain CT/MRI revealed irregularly shaped, well-defined, homogeneous, and mainly progressive lesions, with marked homogeneous enhancement on multiphasic contrast-enhanced imaging. One patient had dural lesions, one of which iso-intense to grey matter, with patchy hypo-intensity on T2-weighted imaging, meningeal tail signs, and characteristic crabfoot-like enhancement. Three patients with skeletal system involvement exhibited osteolytic bone destruction without sclerosis at the edges, associated soft-tissue masses, or periosteal reactions. Two patients had well-defined subcutaneous lesions, inhomogeneous density, and progressive parenchymal enhancement on contrast-enhanced CT. One patient had multiple intestinal lesions with inhomogeneous nodular thickening of the blind ascending colon and ileum, with marked and progressive enhancement. RDD involvement is mainly multifocal, primarily in the head and neck regions. Plain CT/MRI revealed well-defined, irregularly shaped lesions with homogeneous density/signal, with marked and progressive enhancement on multiphasic contrast-enhanced imaging; however, histopathology is still required to confirm the diagnosis of RDD.