Complex lymphatic anomalies (CLA) are extremely rare sporadic diseases of genetic origin, primarily affecting children, adolescents, and young adults. According to the International Society for the Study of Vascular Anomalies classification, there are five types of CLA: generalized lymphatic anomaly (GLA), Gorham-Stout disease (GSD), kaposiform lymphangiomatosis, central conducting lymphatic anomaly, and generalized lymphatic dysplasia. These lymphatic malformations are characterized by lymphatic proliferation under the influence of vascular endothelial growth factor. Our educational exhibit aims to briefly review the pathophysiology of CLA and illustrate the spectrum of lesions in 14 patients, including 9 with GSD and 5 with GLA. Gorham-Stout disease, also known as vanishing bone disease, is characterized by progressive bone destruction with cortical resorption. The primary lesion, a punched-out osteolysis, typically extends from the initially affected bone to nearby bones and is more frequently observed in the axial skeleton (skull, spine, ribs, pelvic bones and shoulder girdle). It can progress rapidly and sometimes stabilize spontaneously. There is usually no periosteal reaction or bone reconstruction. Patients can present with pain (particularly in case of pathological fracture and vertebral collapse), chronic lymphedema, lower limb length discrepancy, assymetric girth, scoliosis/kyphosis, pericardial ou pleural effusion, and rarely meningitis due to a breach of the skull base. Generalized lymphatic anomaly, formely called lymphangiomatosis, is a diffuse or multicentric disease involving soft tissues, bones, spleen, liver, intestine, lungs, mediastinum, and skin. Thoracic involvment may result in respiratory failure due to chylous pleural effusion, interstitial syndrome or restrictive syndrome related to spinal deformity, as well as pericardial effusion. Bone lesions primarily involve the axial skeleton, as in GSD. Compared with GSD, bone lesions may be multifocal, bone destruction is less severe and fracture are uncommon. Abdominal involvement includes splenic lesions, retroperitoneal mass, ascites, intestinal hemorrhage, and lymphorrhea. Read More

Meeting name: IPR 2026 Congress , 2026

Authors: Chalard François, Barillon Jeanne, Blondiaux Eleonore, Ducou Le Pointe Hubert

Keywords: Lymphatic Malformation, Generalized Lymphatic Anomaly, Children

Langerhans cell histiocytosis (LCH) is an inflammatory myeloid tumor, a rare disease that is most often diagnosed in early childhood. Here, we present the radiological spectrum of manifestations of this disease. The organs most frequently affected are the bone, skin, central nervous system (CNS), lungs, bone marrow, liver, spleen and lymph nodes. Our review includes illustrations of the regression of severe lung lesions and neurodegenerative lesions, which can be observed under targeted therapy (mitogene-activated protein kinase inhibitor). In addition, for each lesion, we present a short list of differential diagnoses. Bone Langerhans cell histiocytosis is a potentially multisystem disease, but its most common presentation is a single-bone lesion. It predominantly affects the axial skeleton, with the skull being the most frequently affected bone. Bone lesions generally develop slowly and can sometimes be aggressive. Vertebra plana is a classic aspect of vertebral LCH ; spinal cord compression is rare. Langerhans cell histiocytosis of the ear primarily affects the mastoid. The ossicles, petrous apex and inner ear are rarely affected. Central nervous system The pituitary stalk is the most commonly affected anatomical region. Other affected sites include the infra- and supratentorial parenchyma, venous sinuses, dura mater, and ventricules. Neurodegenerative lesions are distinct from other LCH lesions and have an affinity for the dentate nucleus, cerebellar white matter, brainstem, and basal ganglia. Lung The initial lung lesions are nodules that gradually excavate to form thin-walled cysts that fuse and may lead to pneumothorax. Pulmonary fibrosis is a late stage of the disease. At risk organs The liver, spleen, bone marrow, and lymph nodes are affected in Letterer-Siwe syndrome, which occurs in infancy. Chronic hepatobiliary LCH is characterized by sclerosing cholangitis that can progress to biliary cirrhosis. Read More

Meeting name: IPR 2026 Congress , 2026

Authors: Chalard François, O'keane Aurélie, Blondiaux Eleonore, Ducou Le Pointe Hubert

Keywords: Langerhans Cell Histiocytosis, Imaging, Education