A 64 year old woman has been on hormone replacement therapy for 5 years

A 64 year old woman has been on hormone replacement therapy for 5 years. She had regular withdrawal bleeds until 3 years ago and has not had a bleeding since. Recently she noticed a brown vaginal discharge on her underpants. Her last cervical smear was 3 years ago which showed no abnormalities. What is the SINGLE most appropriate initial investigation?

A. Cervical smear
B. High vaginal swab
C. Thyroid function test
D. Transvaginal ultrasound
E. Abdominal CT scan

The idea here is to think of endometrial cancer. Any women who has postmenopausal bleeding should have a transvaginal ultrasound to determine the endometrial thickness. If the endometrium is thick, hysteroscopy with endometrial biopsy would be arranged. The hormone replacement therapy in this scenario has no relevance as HRT (progesterone and oestrogen) is not a risk factor for endometrial cancer. Only unopposed oestrogen would be a risk factor for endometrial cancer. A cervical smear is offered every 5 years in the UK if in the age group of 50 to 64 years old. Thus, having a cervical smear that was normal 3 years ago is a usual phenomenon. A repeat cervical smear is not necessary. Endometrial cancer Endometrial cancer is classically seen in post-menopausal women. Classically, endometrial cancer presents as postmenopausal bleeding (PMB) and, although this is not the only cause, it must be excluded. Risk factors for endometrial cancer: • Obesity • Nulliparity • early menarche • late menopause • unopposed oestrogen. The addition of a progestogen to oestrogen reduces this risk (e.g. In HRT). The BNF states that the additional risk is eliminated if a progestogen is given continuously • diabetes mellitus • tamoxifen • polycystic ovarian syndrome Features In PLAB, they will always present with postmenopausal bleeding Investigation • first-line investigation is trans-vaginal ultrasound - a normal endometrial thickness (< 4 mm) has a high negative predictive value • hysteroscopy with endometrial biopsy gives the definitive diagnosis