The site of the lesion may suggest certain diagnoses (Fig 124.16 ) Ewing tumor typically involves the lateral aspects of the ribs Chondrosarcoma typically involves the costal cartilages between the sternum and the distal rib end The sternum is a favored site for anaplastic sarcomas These last two tumors may extend into the thoracic cavity, as well as outside the bony thorax Management If the clinical and radiologic picture clearly indicates a benign, self-limited process, observation may be appropriate However, if there is concern that the lesion is not benign, even a small chest mass in a child should be considered malignant and biopsy is appropriate Initial management of patients presenting with respiratory distress includes supplemental oxygen administration, evaluation for pleural and pericardial effusions with aspiration or tube thoracostomy drainage if present, and pain management if clinically indicated Radiographic evaluation should include a CT scan of the pertinent area and a metastatic bone survey If a malignant process is suspected, oncology and surgical consultations are warranted Multimodal, coordinated treatment is frequently required involving surgical resection, chemotherapy, and radiotherapy Initial biopsy should be done using a core needle technique or a limited open approach, with care to place and orient the incision so as not to compromise the subsequent resection and chest wall reconstruction Preoperative chemotherapy and radiotherapy may be useful to shrink selected lesions Resection of the tumor and of subsequent recurrences have resulted in disease-free survivals of 15 years or more Extensive chest wall resections may result in thoracic instability and paradoxical chest wall motion Technical advances have included the use of rigid materials such as mesh and methylmethacrylate, and together with improvements in surgical technique and postoperative care, significant resections including sternectomy or vertebrectomy can be done safely with excellent preservation of chest contour and respiratory function Suggested Readings and Key References General Coran AG, Adzick NS, Krummel TM, et al., eds Thorax section In: Pediatric Surgery 7th ed Philadelphia, PA: Elsevier Saunders; 2012;771–960 Tracheal Obstruction