A Pap smear involves lightly scraping the surface of the cervix to collect cells. A pathologist then examines a Pap smear under a microscope, looking for two types of cervical cells: squamous cells, which are typically found in the outer surface of the cervix, and columnar endocervical cells, which come from the lining of the narrow opening in the cervix leading to the inside of the uterus (the endocervical canal). Pathologists report on the appearance of both types of cells, and they report if no endocervical cells are seen, as in your case. Your ob-gyn is correct that this is not unusual in a woman who has gone through menopause. The reason is that after menopause, the cervix may be less pliable and the transformation zone (the section of the endocervical canal where squamous cells begin to change to columnar cells) moves higher up the cervical canal, making it more difficult to routinely obtain endocervical cells. However, in a premenopausal woman, the transformation zone is fairly close to the opening of the cervix, allowing the smear to capture both types of cells easily. At your next yearly exam, you could discuss with your ob-gyn your concern about prior Pap smears lacking an endocervical component. He or she may be able to make a special effort to reach the endocervical canal with the Pap instrument. Sometimes, if it is difficult to reach the cervical canal, a small brush can be inserted into the canal to obtain the endocervical component. Learn more in the Everyday Health Cancer Center.
