(P 18) RETROSPECTIVE ANALYSIS ON OUTCOMES PEDIATRIC PATIENTS WITH SARCOMA AND LUNG METASTASES STATUS POST PNEUMONECTOMY VERSUS PARTIAL LUNG RESECTION

Objective: Complete resection has been shown to be an important favorable prognostic factor after pulmonary resection in osteosarcoma and soft tissue sarcoma. This retrospective analysis reviewed the outcomes of pediatric patients with sarcoma and lung metastasis who underwent pulmonary nodular surgery for lung metastases. There is limited data showing the efficacy and morbidity among pediatric patients who have received pneumonectomies for definitive pulmonary nodule resection. The goal of this study was to determine the difference between the type of pulmonary resection procedures, namely thoracoscopy, thoracotomy, and pneumonectomy in pediatric sarcoma patients with pulmonary metastases and their impact on acute complications, disease recurrence, and survival.

Methods: Retrospective data was collected from a single tertiary center to investigate the outcomes of pediatric patients with a primary diagnosis of sarcoma and pulmonary metastases who underwent pulmonary surgery at this institution between 2010 and 2023. Primary tumors in the lung or chest were excluded. For those with more than one pulmonary surgery, only the first surgery was included unless they had a pneumonectomy. Relevant information pertaining to the included patients was collected from medical records and electronic databases. This includes but is not limited to demographic data, primary tumor characteristics, metastatic disease details, surgical procedures performed, postoperative outcomes, and long-term follow-up data.

Results: Twenty patients (14 M, 6 F) with the median age at diagnosis being 13y (2-24) and surgery being 15y (range 7-24) were included. Diagnoses were osteosarcoma (n=12), rhabdomyosarcoma, Ewing sarcoma, high-grade sarcoma (n=2 each), synovial sarcoma, and MPNST (n=1 each). Most primary tumors were located in the extremity (13 lower extremity, 6 upper extremity, and one central location). One-third (n=7) had lung metastases at diagnosis and all were treated with upfront chemotherapy, surgery, and/or radiation. The pulmonary surgical summary is listed in Table 1. All patients who underwent pneumonectomy (n=5) had unilateral disease, nodules larger than 1 cm, and hilar location. Patients who underwent thoracotomy (n=8) mostly had bilateral disease (88%) whereas those who underwent thoracoscopy (n=7) mostly had unilateral disease (85%). Those who underwent pneumonectomy had the greatest blood loss at the time of surgery, but their length of stay was not substantially different than those who underwent thoracotomy. In the total group, the median progression-free survival (PFS) from the time of surgery was 132 days and overall survival (OS) was 770 days. No differences were seen in PFS between the three groups, however, the OS was improved in the group who underwent pneumonectomy.

Conclusion: Surgical resection of metastatic disease in sarcoma can provide disease control for patients. This analysis was limited by the small numbers at a single institution to do a true comparison analysis. Our cohort of pediatric patients was able to undergo pneumonectomy safely without significant complications compared to other lung surgeries traditionally used for pulmonary nodule resection and may provide another modality used in certain clinical scenarios to render patients surgically disease free that may benefit long-term outcomes.