What happened, in summary

An 82-year-old man undergoing follow-up for chronic obstructive pulmonary disease was found to have two solid masses in the left upper lung. Biopsy confirmed squamous cell carcinoma, and preoperative imaging suggested possible mediastinal lymph-node involvement but no distant metastases. He underwent left upper lobectomy with lymph-node dissection. During surgery, the team discovered a complete congenital absence of the left pericardium, leaving the heart fully exposed. Because the remaining lower lobe was expected to provide adequate support, the pericardial defect was not repaired. Final pathology showed two synchronous squamous cell lung cancers without lymph-node involvement, classified as Stage I. He recovered without major postoperative complications and was discharged on postoperative day 8. Follow-up imaging showed displacement of the heart and elevation of the left diaphragm, but his overall condition remained good at 5 months. The two lung tumors were treated together in a single operation and are therefore kept as one integrated cancer journey.