Chest wall tumors are uncommon. They can be either benign or malignant. Chest wall tumors form in the walls of the chest cavity, which protect the lungs and heart. Chest wall tumors are either primary or secondary (metastasized). Secondary chest wall tumors are usually malignant.
The most common primary malignant chest wall tumors are called sarcoma tumors—chondrosarcomas specifically. Chest wall sarcomas form in the bones, soft tissues, and cartilage of the chest cavity. Metastatic lesions (particularly from breast cancer) can also occur.