This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oesophagus, Subject name: Surgery
Endoscopic ultrasound is extremely useful in staging which tumor? 
Select and explain. 
A. Cancer colon, B. Cancer esophagus, C. Cancer stomach, D. Cancer head of pancreas
B: Cancer esophagus
Answer: B: Cancer esophagus 
Explanation: Ans. (b) Cancer esophagusRef: Bailey and Love 26th Edition, Page 990EUS helps in diagnosis and staging of:* Esophageal cancer (Most useful)* Rectal cancer* Gastric cancer* Pancreatic head cancer.