Laparoscopic Ultrasound (LUS) is an important part of the pre-treatment evaluation of patients with upper gastrointestinal tract cancer (esophageal, gastric, pancreatic and liver cancer). When a suspect lesion is visualized during LUS a biopsy should be provided in order to differentiate between benign and malignant lesions. A new system for LUS guided biopsy has been developed, but how often these biopsies are clinically relevant (i.e. changing patient management)and how reliable are these biopsies are unknown.