CANCER OF THE UTERINE CERVIX
It is well accepted that the vast majority of cervical cancers begin from a virus (human papilloma virus-HPV) infecting the cells and, via various biological mechanisms, transforms the cells from benign to malignant status. Factors as immune suppression (genetic, infections as with HIV, smoking) appear to enhance and promote these changes. The HPV stays in the tissues of the cervix indefinitely and may have been present many years before malignant changes are manifested. Sometimes these changes never appear. Although there are over 45 human serotypes of HPV, only 5 - 6 have the ability to transform normal cells to malignant cells.
Detection of Tumors:
Pap smears continue to be the first line of diagnosis for malignant changes in the uterine cervix. They should be viewed totally as a screening procedure and never as a diagnostic test since there is only a 70 - 85% accuracy rate with one pap smear. Accuracy tends to improve with a second and third pap smear that is in agreement with the first smear (92% and 98%, respectively). Pap smears may be accurately read as "normal" in occasional cases of invasive cervical cancer when all previous smears over 5 - 6 consecutive years were read as "normal". The HPV will often manifest itself on a pap smear with abnormal changes in the cells (and nucleus) but not necessarily as dysplastic, premalignant/malignant changes.
Evaluation of the Abnormal Pap Smear:
If the pap smear is interpreted as abnormal but less than dysplastic/premalgnant/malignant changes, then it should be repeated in 2 - 3 months. If still abnormal, then the patient should have a polposcopic examination with biopsy of any abnormal area(s). If the repeat pap smear is "normal" then a pap smear should be repeated within 6 - 12 months. At any time there is dysplastic/premalignant/malignant changes on the pap smear and/or abnormal uterine bleeding associated with an abnormal pap smear, colposcopic evaluation with appropriate biopsy(ies) are essential. Biopsy of any grossly abnormal area on the cervix especially associated with an abnormal pap smear is warranted.
Frequency of Obtaining Pap Smears:
Generally pap smears should be obtained by 21 years of age or sooner if sexual activity has preceded that age. Annual pap smears continue to be recommended unless a patient has had a hysterectomy with a normal cervix and/or if the patient has never had abnormal smears and is beyond 80 years of age. In the former case pap smears can be obtained every 2 - 3 years while in the latter case pap smears can be obtained as indicated (vaginal discharge, bleeding and/or pain). Any patient who has had an abnormal pap smear and/or has been treated for dysplastic/premalignant/malignant changes needs, as a minimal follow-up, annual pap smears, assuming that the abnormal changes have been eliminated.