Well differentiated endometrioid adenocarcinoma of the uterus: a cancer unit or centre case?

The purpose of this study was to investigate what proportion of cases showing a well differentiated endometrioid endometrial adenocarcinoma in the hysterectomy specimen removed at two UK cancer centres had adverse pathological features or advanced stage disease at the time of presentation.

Ninety-eight patients who were operated on at either the South East London Cancer Centre, London or the Kent Oncology Centre, Maidstone had a histological diagnosis of well differentiated (grade 1) endometrioid adenocarcinoma in their hysterectomy specimen. These were identified using the multidisciplinary meeting database as well as the respective pathology department databases. The histology reports for these patients were examined and analysed for the purpose of this study.

Of the initial 98 cases, 65 patients (66.3%) were referred with a preoperative curettage showing a well differentiated endometrioid adenocarcinoma, 25 cases (25.5%) were referred with atypical endometrial hyperplasia, seven patients (7.1%) were referred with a moderately differentiated endometrioid adenocarcinoma, and one case (1.0%) was referred with a possible malignant mixed Mullerian tumour. Subsequent histological examination of the hysterectomy specimens revealed that all of these cases had a well differentiated endometrioid adenocarcinoma. In 20 of the 98 cases (20.4%) there was no myometrial invasion, 56 cases (57.1%) showed invasion of the inner half of the myometrium and 22 cases (22.4%) showed outer half involvement. There was no cervical involvement in 78 cases (79.6%), endocervical gland involvement in eight patients (8.2%) and cervical stromal involvement in 12 patients (12.2%). The total percentage of cases with cervical involvement was 20.4%. Thirty-eight cases (out of the 98) underwent a bilateral pelvic lymphadenectomy. Of these 38 cases, four cases had locoregional nodal metastases (10.5% of the patients who underwent lymphadenectomy). There were ovarian metastases in one case and metastasis to one fallopian tube in another. From our study, 33.6% of cases with a well differentiated endometrioid adenocarcinoma of the uterus were Stage Ic or more at the time of presentation; 12.2% were at least FIGO Stage Ic, eight patients (8.2%) were FIGO Stage IIa, seven patients (7.1%) were Stage IIb and six patients (6.1%) were Stage III. In these patients a full surgical staging operation with a pelvic lymphadenectomy was indicated according to FIGO recommendation.

A significant proportion (33.6%) of well differentiated tumours in a hysterectomy were found to have Stage Ic disease or more at the time of presentation, and thus full surgical staging including a lymphadenectomy should have been carried out in these cases. Cases with a preoperative biopsy showing atypical hyperplasia or well differentiated adenocarcinoma should have a preoperative MRI scan or preferably an intraoperative frozen section examination to identify those cases with adverse pathological features which need to be fully staged with pelvic and paraaortic lymphadenectomy.