Then general term of dysplasia is as simple as a cell, (or even an organ) which is not normal. However, when oncologists refer to dysplastic cells, they are comparing them to surrounding cells of the same type. No cell goes from normal to malignant without a variety of in-between transformations. These alterations of various components of the cell make it dysplastic. Some alterations are more ominous than others, an enlarged nucleus for instance is very characteristic of cells that are malignant, while other changes a few in the mitochondria, would qualify as dysplastic but not necessarily one of the changes commonly seen in cells in transition to full blown malignancy. Daughter cells produced as these dysplastic cells replicate need further genetic alteration to finally become a malignant cell. One of the most common characteristics of malignant cells besides the enlarged nucleus is the lack of p-53 which is the gene that causes natural apoptosis, or programmed cell death. One commonality in cancer cells is that they are (without p-53) essentially immortal. So while dysplasia is a general term, on a cellular level there are different dysplasias - some of greater concern than others. Of course one of the great mysteries is why some dysplastic cells go on to further changes and others do not.

As to cause, few will ever know for sure. In oral cancers, non-smokers exposed to second hand smoke for long periods would raise an eyebrow, ditto HPV 16 or 18 positive cells. But in the development of malignancy, without the introduction of a known causative agent such as the 400 carcinogens produced in tobacco combustion, we are essentially clueless. In some cases we are still guessing. The recent loss of Reeve to lung cancer is being discussed heavily, and the