ABNORMAL VAGINAL CYTOLOGY PERSISTS AFTER RADIOTHERAPY FOR ENDOMETRIAL CANCER 

NEW YORK (Reuters Health) Dec 21 - Postoperative vaginal cytology apparently has limited utility for detecting recurrent endometrial cancer, as low-grade abnormalities are associated with prior radiotherapy rather than recurrence, a St. Louis team reports.

In this setting, "Colposcopy is not needed after a Pap test result read as atypical squamous cells of undetermined significance or LSIL (low-grade squamous intraepithelial lesion)," the researchers conclude in their paper in the January issue of Obstetrics & Gynecology.

Dr. Akiva P. Novetsky, at Washington University School of Medicine, and colleagues reviewed their data on 433 women treated for endometrial cancer who had at least one liquid-based Pap test after a total hysterectomy.

Overall, 51 of the women had recurrent endometrial cancer, of which 10 involved vaginal recurrence, according to the report. Also, 55 women had at least one abnormal cytology result, which in 67% of cases was classified as atypical squamous cells of undetermined significance (ASC-US) or a low-grade squamous intraepithelial lesion (LSIL).

However, "No woman (zero of 37) with ASC-US or LSIL Pap test results had a vaginal recurrence," the team found.

On the other hand, 42 women with normal surveillance Pap test results did have a recurrence of endometrial cancer. Five of these recurrences involved the vaginal cuff and were diagnosed following vaginal bleeding.

On multivariate analysis, adjuvant radiotherapy was significantly associated with abnormal cytologic findings (hazard ratio 2.51; p<0 .001=".001" p="p">

The authors calculated that the positive predictive value of an abnormal Pap test result in detecting local recurrence was 7.3%, and the negative predictive value was 98.4%.

"Our study supports previous studies demonstrating the significant limitation of Pap tests in diagnosing recurrent endometrial cancer," Dr. Novetsky and colleagues comment. They note that their study has several limitations, but conclude, "We propose that performance of vaginal cytology in patients treated for endometrial cancer is of low yield and therefore unnecessary."

SOURCE: http://bit.ly/Zot3j7

Obstet Gynecol 2013;121:129-135.