Occult Endometrial Cancer: An Unfortunate Coincidence? Dr Megan Wright, Miss Sue Ward

Case 1: Following Vaginal Hysterectomy for Prolapse

71 Posterior wall prolapse causing post coital soreness

Elective vaginal hysterectomy with posterior repair

Incidental histological finding of grade 1 stage 1a endometrial cancer

Gynaecological-oncology multidisciplinary team meeting

Laparoscopic bilateral salpingo-oophorectomy as completion surgery

Bilateral serouscystadenofibromas: Right ovarian volume 43x32x21mm; Left ovarian volume 34x17x12mm

Past Medical History: • Bilateral knee osteoarthritis • No post-menopausal bleeding • Otherwise fit and well

Prior to laparoscopic bilateral salpingo-oophorectomy

Occult endometrial cancer is defined as incidental surgical histology finding of cancer where malignancy was not suspected pre-operatively. A UK study of 517 vaginal hysterectomiesfor prolapse, and no history of post menopausal bleeding, found an incidence of 0.8% occult endometrial cancers (1).

Pre-operative Screening

Historically dilatation and curettage was undertaken prior to vaginal hysterectomy and surgery abandoned if tissue obtained; however, this was not validated in asymptomatic women (2). Transvaginal ultrasound with endometrial thickness >11mm indicates a 6.7% endometrial cancer risk (3). However, asymptomatic screening is not routinely recommended – such as in above cases.

Ovarian Tumours Found (4)

In both cases epithelial type ovarian tumours were seen. This is the most common type, followed by germ cell then sex-cord stromal tumours. Serous cystadenofibroma: Mix of epithelial and fibrous cells and more often bilateral. Mucinous cystadenoma: Mucin containing epithelial cells, more often multiloculated, thin walled, unilateral and larger.

Case 2: Following Total Abdominal Hysterectomy for Ovarian Cyst

40 Emergency admission with torsion of massive ovarian cyst

G0P0 Ca125 - 33 αFP - 2 ΒHCG <0.2 Pre-menopausal

Gynaecological-oncology multidisciplinary team meeting

Total abdominal hysterectomy with bilateral salpingo-oophorectomy and omentectomy / peritoneal washings

Right ovarian benign mucinous cystadenoma Incidental histological finding of grade 1 stage 1a endometrial cancer

Imaging explained: MRI (above) shows massive right ovarian cyst (26x24x14.5cm) The thick cyst wall, inner irregularities and multiple septa increase suspicion of borderline or cancerous type (4). Transvaginal Ultrasound (right) shows the uterus with view of the endometrium and the cervical canal. In premenopausal women endometrium is thicker due to regular menstruation.

Conclusion

We describe 2 cases of occult endometrial cancer in the same month at a district general hospital. In neither case was there an indication for preoperative endometrial sampling. These cases emphasize the importance of histological examination of the uterus. References: 1. Renganthan A. Edwards R. Duckett JRA. Uterus conserving prolapse surgery – what is the chance of missing a malignancy? Int Urogynecol J 21, 819-821 (2010). 2. Stovall TG. Solomon SK. Ling FW. Endometrial sampling prior to hysterectomy. Obstetrics and Gynecology 73(3 Pt 1),405-409 (1989). 3. Smith-Bindman R. Weiss E. Feldstein V. How thick is too thick? When endometrial thickness should prompt biopsy in postmenopausal women without vaginal bleeding. Ultrasound Obstet Gynecol 24, 558-565 (2004). 4. Foti PV. Attinà G. Spadola S. Caltabiano R. Farina R. Palmucci S. Zarbo G. Zarbo R. D'Arrigo M. Milone P. Ettorre GC. MR imaging of ovarian masses: classification and differential diagnosis. Insights Imaging. 7(1),21-41 (2016)