Peripheral primitive neuroectodermal tumor of chest wall in young adult

A 27-year old man attended the health unit complaining of thoracolumbar pain radiating to the anterior region of his right hemithorax. Computed tomography (CT) identified the presence of a spindle-shaped mass on the anterolateral wall of the right hemithorax, with an osteolytic lesion in the costal arch. No sign of distant metastasis was found. Percutaneous biopsy, histopatho-logical and immunohistochemical analyses were performed, with diagnosis of primary neuroectodermal tumor (PNET). Within one month, a remarkable growth of the lesion was observed, with local dissemination to the pleura and onset of distant metastasis, particularly in the axial skeleton, affecting several bone elements. Neoadjuvant chemotherapy was initiated and 50% reduction in tumor volume was demonstrated at magnetic resonance imaging (MRI). Wide surgical resection was performed with placement of a Marlex mesh for the chest wall reconstruction. Adjuvant chemotherapy was reinitiated after the surgery. Eight months after the disease onset, the clinical condition presented unfavorable progression with onset of innumerable meta-static pleural lesions and progressive lower limbs paresthesia and paresis. Also, the onset of new bone metastases invading thora-columbar and sacral vertebral bodies was observed, with paraple-gia resulting from rachidian canal invasion. The patient was admitted with cachexia, dyspnea while talking and difficult-to-control chest pain, and progressed to death. Chest imaging evaluation has been the subject of a series of recent publications in the Brazilian radiological literature (1–7). Peripheral PNETs are extremely malignant tumors and bones and soft tissues are their primary sites. Most frequently, such tumors affect the chest wall, paravertebral region, pelvis and limbs, and also are described in a range of organs such as kidneys , urinary bladder and heart (8). PNET of the chest wall may affect the ribs, sternum, scapula, clavicle and soft tissues of the chest wall and pleura (9). Frequently, these tumors affect children and adolescents, with incidence peak between 15 and 25 years. About 80% of patients are under the age of 20 at the moment of the diagnosis (10). The common presentation of chest wall PNETs is chest pain followed by increase in local volume and/or mass sensitive to pal-pation, and dyspnea. Pleural effusion is observed in cases where such tumors affect the pleura. Distant metastases occur in lungs, bones, bone marrow, liver and brain (11). The PNET prognosis is related with adjacent structures invasion. About 30% of patients present with metastasis at the moment of the diagnosis (12). CT findings include ill-defined heterogeneous mass, …