Malformation lymphatique macrokystique atypique chez un adulte

Macrocystic lymphatic malformations (MLMs) constitute a circumscribed variation in deep lymphangiomas. They are characterized by a rare occurrence in adults, by their rapid expansion and by their frequent occurrence at the level of the cervicofacial region (75%) and axillary region (20%). They rarely occur in lower limbs. The diagnosis of MLMs is primarily based on clinical examination. Ultrasound has a valuable role in positive diagnosis and sometimes in differential diagnosis. MRI has a role in the diagnosis and the assessment of tumor extent, thus making a valuable contribution to surgery. Therapeutically, MLMs are mainly treated by sclerotherapy; surgery is rarely indicated. We report the case of 26-year old man with a one-year history of huge painless and rapidly evolving subcutaneous swelling in the right thigh. Clinical examination showed circumferential compressible non-beating infiltrated mass, surmounted by vegetative and ulcerated lesions. The remainder of the clinical examination showed the presence of inguinal ipsilateral lymphadenopathy, with mobility limitation of the right knee. Angio-MRI objectified diffuse heterogeneous gadolinium-enhancing cutaneous, subcutaneous thickening of the right thigh with perimuscolar aponeurotic involvement. Lymphoscintigraphy showed asymmetry of the accumultion of radiopharmaceutical kinetics that was reduced in the right lower limb in favor of an overload of the lymphatic system at rest. Given the clinico-radiological data, the diagnosis of MLM was retained. Given the seat of the lymphangioma and its extent, after consultation with the surgeons there was no indication for surgery. Immobilization with a removable bandage was indicated for our patient.