This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Surgery
In patients with breast cancer, chest wall involvement means involvement of any one of the following structures except 
Select and explain. 
A. Serratus anterior, B. Pectoralis Major, C. Intercostal Muscles, D. Ribs
B: Pectoralis Major
Answer: B: Pectoralis Major 
Explanation: Chest wall involvement means involvement of ribs, intercostal muscles or serratus anterior as chest wall is formed by these structures not the pectoral is major Ref: schwaz's principle of surgery 10th edition Pgno :452