Could Cancer Cells Be Selectively Targeted by Using Antibodies Recognizing

Multiple Choice

Could cancer cells be selectively targeted by using antibodies recognizing a tumor-specific protein marker? Researchers grafted human cancerous cells onto 20 healthy adult mice and then randomly assigned 10 of these mice to be treated with tumor-specific antibodies. They found that only 1 of the 10 mice treated with antibodies developed metastases (i.e., new cancer growths) , whereas all 10 of the 10 mice in the control group developed metastases. Call (1) the treatment population (injected with antibodies) and (2) the reference population (untreated controls) .
What is the number needed to treat, NNT, to prevent one mouse from developing metastases when treated with tumor-specific antigens compared with no treatment?

A) 1
B) 1.11
C) 9
D) 10