This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Most common histological subtype of lung cancer associated with pancoast tumor? 
Select and explain. 
A. Small cell cancer, B. Squamous cell cancer, C. Adenocarcinoma, D. Carcinoid tumor
B: Squamous cell cancer
Answer: B: Squamous cell cancer 
Explanation: None