Pathology Sentinel lymph node is defined as: A First node in a regional lymphatic basin that receives flow from primary tumor B First lymph node to be biopsied in the tumor C First lymph node that is positive for malignancy in a tumor D Lymph node that is positive for malignancy and more than 2 cm in diameter 💡 Explanation Sentinel lymph node is defined as: ✓ Correct Answer: A. First node in a regional lymphatic basin that receives flow from primary tumor