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What is Endoscopic ultrasound is extremely useful in staging which tumour? and explain in detail?
Ans. is 'b' i.e., CA Esophagus Investigations for Ca EsophagusFirst investigation done in suspected cases is - Barium SwallowClassic finding on Barium swallow suggestive of Ca - Apple core lesion (irregular stricture with shouldering)Investigation to confirm malignancy - Endoscopy with biopsyInvestigations for staging :i) CECT abdomen : it assess the length of the tumor, invasion of adjacent structures, regional lymph nodes and metastasis to lungs and liver. It also assess whether the tumor is resectable or not.ii) Endoscopic ultrasound : investigation of choice to assess the T stage of tumor and Lymph node metastasis