Thank you for your question. This answer will provide communication for why pap smears are still relevant for women who've had a
hysterectomy.
Pap smears are a screening test to help doctors decide who needs further evaluation. You had an abnormal pap many years ago which led to freezing of the cervix (called
cryotherapy). This is usually done for low grade lesions called mild or moderate
cervical dysplasia (abnormal growth of cells) which can destroy these cells. However,
human papillomavirus (HPV) is a viral infection and there is really no cure. There are 13 subtypes of HPV that may cause cell changes that can lead to
cervical cancer if left untreated. Cervical dysplasia can be a precursor to cervical cancer.
Unfortunately, removing the cervix through hysterectomy does not protect from
HPV infection. The virus is still there and may cause changes in the vagina. Therefore, women with a history of abnormal pap smears, despite having had a hysterectomy, still need pap smears. The frequency of pap smears after hysterectomy is debatable.
You should expect that your doctor will perform another colposcopy, looking closely at the tissue at the top of the vagina where the cervix used to be. I have not seen a cancer of the vagina from an abnormal pap smear after hysterectomy, but I see about ten women a year with this problem. Biopsy may be performed if an abnormality is detected with colposcopy. I just recently had this happen in a woman who had a daVinci hysterectomy in 2007. She had a history of cryotherapy for mild dysplasia several years before her hysterectomy and had requested an annual pap smear despite her hysterectomy.
If dysplasia is found, it can be treated with cryotherapy, a laser, or a loop excisional procedure. These can all be performed in the office with
local anesthesia and minimal discomfort.
This is probably the worst case scenario without knowing the actual result of your pap smear. If the pap smear shows atypical cells only, that is a frequent finding in women who merely have HPV infection. In this instance, the pap smear is usually followed on a more frequent basis. However, pap smears have a high false negative rate (around 40%). This can mean the pap smear is normal, even when there really is an abnormality.
I hope this answers your questions but I am available for follow up if needed.