Cervical implantation metastasis by endometrial adenocarcinoma.

A distinct type of cervical involvement by endometrial cancer is reported and termed cervical implantation metastasis. It is believed to result from implantation of endometrial cancer on the denuded endocervix after fractional dilatation and curettage (D & C). The histologic criteria for diagnosis are: (1) the cervical implantation metastasis must be imbedded in the endocervical epithelium or superficial stroma surrounded by an implantation site of inflammatory cells and granulation tissue (free-floating cancer cells above the cervical mucosa are not acceptable as implantation tissue), (2) the histologic findings of the cervical implantation metastasis must be similar to those of the endometrial adenocarcinoma in the uterine corpus, (3) the cervical implantation metastasis must be separate from the primary tumor with no evidence of direct extension, and (4) the cervical implantation metastasis should be surrounded by nonneoplastic endocervical glands with no transition between the two. Of the 176 patients who underwent fractional D & C before hysterectomy, nine (5%) were found to have cervical implantation metastasis. No patients had cervical implantation metastasis who did not undergo fractional D & C before hysterectomy. When stratified according to stage, grade, and myometrial invasion, there was no statistically significant difference in the recurrence rate between patients with or without cervical implantation metastasis. It appears that cervical implantation metastasis does not alter prognosis or require specific treatment.