Sinonasal myxoma – an unusual cause of a maxilary mass in a child
Myxomas of the head and neck are benign but locally invasive tumors, with involvement of the nasal cavity and paranasal sinuses being extremely rare in pediatric ages, with very few cases reported in the literature. Because of its location and infiltrative behavior, they constitute a diagnostic and therapeutic challenge. The authors report a rare case of a myxoma in a seventeen-month-old male infant, involving the maxillary sinus with extension to the orbit, nasal cavity and ethmoid labyrinth. The computed tomography (CT) revealed a large solid expansile and well-defined mass in the right maxilary sinus, with extension and expansion of the sinus to the homolateral orbit, nasal cavity and ethmoid labyrinth. There is expansion and thinning of the cortical plates of the maxilary sinus walls, that are displaced at the perifery of the sinus cavity. Teeth in the affected region showed displacement and smooth root resorption. Magnetic ressonance imaging (MRI)showed a well-defined lesion with homogeneous signal intensity on every pulse sequence. It is isosignal to muscle structures on T1-weighted images and T2 hypersignal, without restriction to diffusion. Gadolinium was not administered. Patient proceed to facial mass biopsy, that was nondiagnostic. Surgery was then performed with surgical excision of the lesion. Histopathological examination revealed typical features of a myxoma, containing loosely arranged stellate and spindle-shaped cells within a myxoid matrix.