cancer-prone zone where vagina and cervix meet
The mucus-producing lining of the cervical canal (called “columnar” tissue after the shape of its outer cells) meets the surface covering of the vagina (made up of squamous epithelial cells) at a line of demarcation called the “squamocolumnar junction.” It is in this shifting zone of disparate cells that abnormal growth is most likely to arise. Central to the Pap test is an adequate sample from this point.