Tumor margins

Tumor margins refer to the edges or boundaries of a removed tumor during surgery or biopsy. They indicate whether cancer cells are present at the outer edge of the tissue sample. Clear or negative margins mean no cancer cells are seen at the edges, suggesting all of the tumor has been removed. Positive margins mean cancer cells are found at the edge, implying some may remain in the body. Properly assessing margins helps doctors determine if additional treatment is needed to reduce the risk of cancer recurrence.