Tumor-specific antigens are?

• A. Unique to cancer cells
• B. Unique to benign cells
• C. Can be found in both benign and cancer cells
• D. Not present

Answer: (B)

Tumor-specific antigens are unique to cancer cells. They arise from changes that occur only in tumor cells, such as mutated proteins (neoantigens), viral oncogene expression, or cancer-testis antigens, so normal cells do not express them. Because these antigens aren’t found on benign or normal tissues, they’re prime targets for immune recognition and cancer therapies with limited off-target effects. Antigens that appear on both benign and malignant cells aren’t tumor-specific, and something not present at all wouldn’t serve as a cancer-specific target.