What happened, in summary

This 61-year-old man had a 30-year smoking history and developed 3 months of progressive swelling in his head, neck, arms, and upper chest, followed by shortness of breath and distended veins in the neck and chest. PET/CT showed a small mass in the upper lobe of the right lung, enlarged mediastinal lymph nodes, and a 7.4 cm mass inside the superior vena cava, the large vein that returns blood to the heart. MRI confirmed the tumor thrombus. Core biopsy of enlarged lymph nodes showed non-small-cell lung cancer, possibly adenocarcinoma. The tumor expressed EGFR protein, but the sample was too small for EGFR gene mutation testing. No distant metastasis was found, and the disease was staged as cT1N2M0, Stage IIIA, with malignant superior vena cava thrombosis. To avoid chemotherapy-related nausea and vomiting that might destabilize the clot, the team treated him with thoracic intensity-modulated radiation therapy plus erlotinib 150 mg/day. Hydrochlorothiazide was used briefly during the first week to relieve superior vena cava syndrome. Radiation was delivered to 66 Gy at 2 Gy per fraction, 5 times per week. His distended veins resolved after 22 Gy, and marked tumor shrinkage was seen after 40 Gy. He was discharged on maintenance erlotinib. At 6 months, the primary lung tumor had completely responded; at 9 months, the superior vena cava thrombus had disappeared. He continued PET/CT and tumor-marker monitoring every 3 months and had no progression through 45 months of follow-up. The sustained response was notable because treatment addressed both the lung tumor and the life-threatening superior vena cava obstruction without upfront chemotherapy.