The effects of the selective cyclooxygenase-2 inhibitor on endometrial cytological findings in uterine endometrial cancer patients.

We previously reported that oral administration of the selective cyclooxygenase-2 (COX-2) inhibitor etodolac results in antitumor effects in endometrial cancer tissue. Herein, we investigated whether these antitumor effects could be assessed using endometrial cytological findings. Etodolac (400 mg b.i.d. for 2 weeks) was administered preoperatively to 21 endometrial cancer patients: 16 had COX-2-positive disease and 5 had COX-2-negative disease. Twenty-one pairs of pre- and post-etodolac-treatment endometrial cytological samples were collected to review changes in the cytological features. In the COX-2-positive patients, nuclear atypia was slightly decreased in 3 of the 16 cases, while the mitotic index was decreased in all cases. Cellular overlapping and tumor cell cluster outlines were somewhat affected in 6 and 8 cases, respectively. Nuclear/cytoplasmic ratio, anisokaryosis and hyperchromasia were also reduced in 6, 4, and 2 cases, respectively; however, tumor diathesis and nucleoli features were unchanged. In contrast, endometrial cytological features did not appear to be affected in the 5 COX-2-negative patients. We conclude that the antitumor effects observed in endometrial cancer tissues following oral administration of etodolac are reflected in and can be easily assessed by evaluating endometrial cytological features.