A 40-Year-Old Woman With Back Pain Andreu Fernández-Codina, MD, Santiago Aranda-Rodríguez, MD, Cleofé Romagosa, PhD, Maria Deu-Martin, PhD, Carmen Parra- Fariñas, MD, Segundo Bujan-Rivas, PhD  CHEST  Volume 150, Issue 6, Pages e159-e165 (December 2016) DOI: 10.1016/j.chest.2016.08.1449 Copyright © 2016 American College of Chest Physicians Terms and Conditions

Figure 1 Presence of freckling in the patient’s left armpit. A brown papule is also noticeable. CHEST 2016 150, e159-e165DOI: (10.1016/j.chest.2016.08.1449) Copyright © 2016 American College of Chest Physicians Terms and Conditions

Figure 2 A, Posteroanterior conventional chest radiograph. There is an image of increased density over the left middle lung field with no infiltration of the adjacent structures and an incomplete border sign that is typical for chest wall tumors. It corresponds to a huge mass occupying almost the entire left hemithorax with contralateral displacement of mediastinal and lung structures. B, Contrast- enhanced chest CT image with coronal reconstruction. A heterogeneous and hypodense soft tissue mass (asterisk) is producing a mediastinal shift to the contralateral side. A moderate amount of loculated pleural effusion and passive atelectasis of the adjacent lung are also noted (arrow). CHEST 2016 150, e159-e165DOI: (10.1016/j.chest.2016.08.1449) Copyright © 2016 American College of Chest Physicians Terms and Conditions

Figure 3 A, Axial contrast-enhanced CT image with a low attenuating and mildly enhancing mass (asterisk), which is displacing the aorta, azygos vein, and esophagus. B, Axial fused photon emission tomography/CT image with an intensely 18-fluorodeoxyglucose avid mediastinal mass (arrow) with a maximum standardized uptake value of 26. C, Axial fused photon emission tomography/CT image with small nodules (maximum standardized uptake value, 3.7) in the right intercostal spaces, suggestive of neurofibromas (arrow). D, Coronal T2-weighted fat saturation MR image of the lumbosacral roots and plexus. Proximal lumbosacral nerves appear to be thickened by the presence of neurofibromas (arrow). CHEST 2016 150, e159-e165DOI: (10.1016/j.chest.2016.08.1449) Copyright © 2016 American College of Chest Physicians Terms and Conditions

Figure 4 Macroscopic image of the tumor once it was removed from the patient’s chest. CHEST 2016 150, e159-e165DOI: (10.1016/j.chest.2016.08.1449) Copyright © 2016 American College of Chest Physicians Terms and Conditions

Figure 5 A, Tumoral area with spindle cells in a collagenized background at 200×. B, Focal staining for S100 monoclonal antibodies at 200× is noticeable. C and D, Highly cellular area with clear atypia and focal pleomorphism (hematoxylin-eosin; 400×) and an area of tumoral necrosis, respectively (hematoxylin-eosin; 200×). CHEST 2016 150, e159-e165DOI: (10.1016/j.chest.2016.08.1449) Copyright © 2016 American College of Chest Physicians Terms and Conditions