Hi meggles~
Could it have been no evidence of koilocytosis?
Borderline changes to mild dyskaryosis is a very common diagnosis. If they said no evidence of koilocytosis, it simply means there was no cellular evidence of HPV. This does not mean HPV is not present, it simply means the cells they sampled do not show the changes.
If you imagine a cell to look somewhat like a fried egg, with the yolk being the nucleus and the white the cytoplasm, a normal cell will have a very tiny yolk and a lot of white. The HPV virus causes the cell's nucleus to enlarge. When there is only a minor enlargement, these cells are called borderline or mild dyskaryosis. When the enlargement of the nucleus is such that it takes over most of the cell, it's called moderate or severe dyskaryosis. This is the diagnosis you don't want!
Koilocytosis is when the cytoplasm around the nucleus is cleared away, leaving a sometimes irregular hole. But this does not happen 100% of the time so the lack of it means very little. If it HAD been present, then you would have known that SOME type of HPV was present, though not necessarily a high risk type.
Mild dyskaryosis is known to regress on it's own, which is why they do not always take an aggressive approach. What your GP said, although it may not be what you wanted to hear, reflects one of the current trends in treatment not only in the UK, but in Australia and the US as well.
....I guess it's an inexact science, and it also depends on which stage you are in your menstrual cycle when you have it done.
From a laymans point of view, I can see why it seems an inexact science. I can assure you it's simply way more complicated than possible to explain easily. There is a reason why it's a shortage profession!