Cytologic Examination to Detect Clear-Cell Adenocarcinoma of the Vagina or Cervix
abstract & commentary
Synopsis: Cervical and vaginal cytology remains an excellent method for detecting clear-cell adenocarcinoma of the cervix and vagina.
Source: Hanselaar AG, et al. Gynecol Oncol 1999;75: 338-344.
The purpose of this study was to determine whether cervical and vaginal cytology is useful in the detection of cases of clear-cell adenocarcinoma (CCA) of the vagina and cervix. Hanselaar and colleagues used the nationwide pathology database of The Netherlands to link cytologic samples and patients with known CCA. All cytology samples in the two years prior to the diagnosis of CCA were included in the study. During the time period of the study, most cytologic diagnoses used the Papanicolaou system. Class I and II smears were considered negative, and Class III, IV, and V smears were considered positive.
Ninety patients with CCA represented the case material. Only 49 of the 90 patients had cytology material available. Of the 83 smears 61% were positive. Eighty-five percent of the cervical CCA cases had a positive cytology sample, and 64% of the vaginal CCA cases were positive.
Some patients had separate vaginal smears obtained. When the source of the smears was examined it was found that a cervical smear detected CCA 85% of the time, but vaginal CCA only 50% of the time. In contrast, vaginal smears detected 100% of the vaginal CCA cases, but missed half of the cervical cases. When the stage of tumor was examined it was shown that many more cases of stage I disease were detected by cytology than higher stage disease.
Hanselaar et al conclude that cytology continues to be an effective way to screen for cases of CCA. They suggest that all diethylstilbestrol (DES)-exposed patients continue to have prospective follow-up.
COMMENT By Kenneth L. Noller, MD
An interesting thing has happened during the past few months—there has been renewed interest in DES- exposed women. I am particularly happy to see this revival since many physicians had taken the attitude that once a DES-exposed woman was past her early reproductive years, she was no longer at risk for DES-associated disease. Nothing could be farther from the truth. Cases of both vaginal and cervical adenocarcinoma continue to occur in women in their forties. Indeed, in women not exposed to DES, the perimenopausal years appear to be associated with the greatest risk of development of the disease. Since most DES-exposed women are in or approaching this age range, they certainly should be screened on a regular basis. For those DES-exposed women who have had no medical problems, once-yearly pelvic examination with cytology that includes a sample from the upper vagina seems sufficient. (The upper vaginal sample can be included on the same slide as the cervical sample or a separate smear can be made.) For those women who continue to have epithelial abnormalities of the vagina (squamous metaplasia, adenosis, VAIN), colposcopy once yearly is suggested.
There is one important addition to the routine pelvic examination that should be performed in all DES- exposed women. Following the collection of the cytology sample and removal of the speculum, a one-finger palpation of the vaginal fornices should be performed. If a subepithelial nodule is detected during this examination, it should be biopsied. Several small clear-cell cancers have been detected and successfully treated in this manner.
Which of the following is true concerning the Hanselaar et al study on CCA?
a. Vaginal smears detected 60% of the vaginal CCA cases.
b. Cervical smears detected cervical CCA 65% of the time.
c. Vaginal smears detected vaginal CCA 100% of the time.
d. More cases of stage I disease were detected in higher stage disease than by cytology.