To differentiate malignancy from benign lesion in GIT, investigation of choice:

Ans. (b) BiopsyRef: Chapter 91: Harrison 18th ed.* Taking multiple biopsies increases the yield. Cytologic examination of tumor brushings complements standard biopsies and should be performed routinely.* The extent of tumor spread to the mediastinum and para-aortic lymph nodes should be assessed by CT scans of the chest and abdomen and by endoscopic ultrasound.* Positron emission tomography scanning provides a useful assessment of resectability, offering accurate information regarding spread to mediastinal lymph nodes