What happened, in summary

A 51-year-old man presented with coughing up blood, weight loss, reduced appetite, chest discomfort, and worsening shortness of breath. Imaging showed a very large mass extending from the mediastinum into the left upper lung, left main bronchus, and left atrium. Biopsy confirmed a poorly differentiated non-small cell lung carcinoma favoring squamous cell histology.

The tumor formed a large intracardiac thrombus that occupied much of the left atrium and moved toward the left ventricle. Surgery was considered unsafe because of extensive involvement of critical cardiac structures. Within 2 weeks, the intracardiac tumor had grown substantially and airway compression worsened. A Y-shaped airway stent improved breathing, and he received outpatient palliative radiation.

Tumor testing showed very high PD-L1 expression at 95%. About 1 month after diagnosis, he began paclitaxel, carboplatin, and pembrolizumab. Despite treatment, his condition deteriorated rapidly. He died 3 months after the initial diagnosis and 2 months after starting systemic therapy.