ASCUS is something you may hear from your gynecologist, and for most of us, they may as well be speaking Greek. What does it mean?
It is an acronym (like SCUBA) that means atypical squamous cells of unknown significance. So it really means that whoever read the slide at the lab can't quite tell what is there. It's not perfectly normal, but not completely abnormal either.
This can happen because your doctor didn't get a good sample. Sometimes the doctor doesn't swab your cervix adequately, and the lab can't interpret the cells. If you're getting your period at the same time as your pelvic exam, the menstrual blood can confuse the sample as well. So sometimes there is absolutely nothing wrong with you, but the sample is just no good.
So while it does not mean that there is cancer. It doesn't mean that there is no cancer either. In order to know for sure, a biopsy would be necessary because nobody knows if it's a bad sample or a real problem lurking underneath.
But if you are HPV negative, your gynecologist will probably tell you to come back in 6 months for another Pap smear.
If you are HPV positive and over 30 years old, your doctor may or may not wait to do a biopsy. If this is your second or third ASCUS result within a year, then your doctor will probably want to look closer and do a biopsy.
At this point, you aren't headed for surgery. The biopsy is really simple (although not painless), and it's done in the doctor's office. The doctor will look at your cervix with a giant magnifying glass called a colposcope just like during a regular exam. Then the doctor will take a metal tool and literally pinch off a bit of the cervix. It's very quick! No stitches are required because the snip is very, very small and will heal on its own.
Then the lab will look at the biopsy to see what is going on. If it's just mild dysplasia, then you'll probably be told to come back in a few months for another Pap smear. If it's moderate or severe dysplasia, then you may need surgery like LEEP to remove the tissue because that type of tissue may turn into cancer.
Basically, though, this is treated like an abnormal Pap smear because they can't say it's normal.