Serous carcinoma arising in endometrial polyps: clinicopathologic study of 4 cases

Uterine serous carcinoma (USC) is a rare variant of endometrial cancer that is not related to increased estrogen level; rather, it arises in a background of atrophic endometrium. Our aim was to describe clinicopathologic features of 4 cases of USC arising in endometrial polyps (EPs). The mean age of the patients at presentation was 53 years (range, 50-61 years). All patients presented with postmenopausal bleeding. In 3 patients, endometrial curretings were done before surgery, which was reported as EP with superficial foci of USC, EP with few clusters of atypical cells, and high-grade serous carcinoma, respectively. All patients underwent hysterectomy with bilateral salpingo-oophorectomy and omental sampling. The uterine cavity showed an EP in all cases ranging in size from 2 to 3.5 cm (mean, 3 cm). The hysterectomy specimens revealed USC in EP as well as the adjacent endometrium in 3 patients. The nonneoplastic endometrium was atrophic in all cases. Residual tumor was not found in the endometrium in 1 case. Omental metastatic deposits were found in all cases. Tumor deposits were also seen in the serosa of uterus, fallopian tubes, and parametrium in 1 case. Two patients died of disease 2 years after diagnosis. The remaining 2 patients are alive after a follow-up of 3 years, respectively. In conclusion, USC is a rare aggressive tumor, and to establish the diagnosis, it is important to look for the small foci of the tumor in the atrophic endometrium and on the surface of the polyps as these patients are likely to harbor additional disease in the uterus or extrauterine sites. The postmenopausal group is at high risk for developing these tumors; therefore, all the endometrial biopsies/curettings and the EPs in this age group should be thoroughly sampled.