POSTMENOPAUSAL BLEEDING

helpful. Postmenopausal Bleeding Definition Postmenopausal bleeding (PMB) is
vaginal bleeding occurring after twelve
months of amenorrhoea, in a woman of the age where the menopause can be expected. Hence it does not apply to a
young woman, who has had
amenorrhoea from anorexia nervosa, or a pregnancy followed by lactation.
However, it can apply to younger women
following premature ovarian failure or premature menopause. Epidemiology It is a common problem representing 5%
of all gynaecology outpatient attendances.1 These are to eliminate endometrial cancer as the cause of the
bleed. Risk factors for endometrial cancer2 It is likely to occur if exogenous
oestrogens are taken. Tamoxifen has an anti-oestrogen effect
on the breast, but a pro-oestrogen effect
on the uterus and bones. Polycystic ovarian disease increases risk. Hereditary non-polyposis colorectal
carcinoma. Obesity combined with diabetes. Use of combined oral contraceptives
decreases risk. Aetiology Non-gynaecological causes including
trauma or a bleeding disorder. Use of hormone replacement therapy (HRT). Vaginal atrophy. Endometrial hyperplasia; simple, complex, and atypical. Endometrial carcinoma usually presents as PMB, but 25% occur in premenopausal
women. Endometrial polyps or cervical polyps. Carcinoma of cervix; remember to check if the cervical smear is up-to-date. Uterine sarcoma (rare). Ovarian carcinoma, especially oestrogen- secreting (theca cell) ovarian tumours. Vaginal carcinoma is very uncommon. Carcinoma of vulva may bleed, but the lesion should be obvious. Management History and examination may possibly
indicate cause, but it is generally
accepted that postmenopausal bleeding
should be treated as malignant, until
proved otherwise. This requires referral to a gynaecologist
with an appointment within two weeks.3 Investigations Transvaginal Ultrasound Scan Where sufficient local skills and resources
exist, transvaginal ultrasound scan (TVUS)
is an appropriate first-line procedure to
identify which women with PMB are at
higher risk of endometrial cancer. The mean endometrial thickness in
postmenopausal women is much thinner
than in premenopausal women.
Thickening of the endometrium may
indicate the presence of pathology. In
general, the thicker the endometrium, the higher the likelihood of important
pathology, i.e. endometrial cancer being
present. The threshold in the UK is 5 mm;
a thickness of >5 mm gives 7.3% likelihood of endometrial cancer.4 A thickness of <5 mm has a negative predictive value of 98%. 2 A recent meta-analysis found that a TVUS
result of 5 mm or less reduced the risk of disease by 84%.5 Some pathology may be missed and it is recommended that
hysteroscopy and biopsy should be performed if clinical suspicion is high.6,7 The accuracy of assessing endometrial
thickness in women with diabetes and obesity has been questioned,8 but models have been developed to take
personal characteristics into account when predicting the risk of cancer. 9 Endometrial biopsy A definitive diagnosis in postmenopausal
bleeding is made by histology.
Historically, endometrial samples have
been obtained by dilatation and
curettage. Nowadays it is more usual to
obtain a sample by endometrial biopsy, which can be undertaken using samplers.
Endometrial biopsy can be performed as
either an outpatient procedure, or under
general anaesthetic (GA). All methods of
sampling the endometrium will miss
some cancers. Hysteroscopy Hysteroscopy and biopsy (curettage) is
the preferred diagnostic technique to
detect polyps and other benign lesions.
Hysteroscopy may be performed as an
outpatient procedure, although some
women will require GA. A significant development has been
direct referral to 'one stop' specialist clinics.10,11 At such clinics several investigations are available to
complement clinical evaluation, including
ultrasound, endometrial sampling techniques and hysteroscopy. Following
such assessment, reassurance can be
given or further investigations or
treatment can be discussed and arranged. Outcome Where pathology is found it needs to be
treated and prognosis will depend upon
the condition and, if malignant, the stage.
One stop clinics provide a fast and
efficient way of investigating PMB. Cautions Most women with PMB will not have
significant pathology but the dictum
remains that: Postmenopausal bleeding is cancer until
proved otherwise. PMB in women on HRT still needs
investigation. An obvious lesion like atrophic vaginitis does not exclude another lesion. Many women are unable to distinguish
between vaginal and urinary bleeding
and some are unable to distinguish rectal
bleeding. One paper found that, in
women presenting with PMB, the
prevalence of bladder tumours was 1.07% and of bladder cancer was 0.7%.12 Tamoxifen Women with breast cancer who take tamoxifen on a long-term basis are at
increased risk of endometrial cancer. In
view of the increased risk of endometrial
cancer associated with tamoxifen
therapy, there is a case for heightened
vigilance for postmenopausal bleeding by both the women and the clinician(s)
responsible for their care.
Ultrasonography is poor at differentiating
potential cancers from other tamoxifen-
induced thickening because of the
distorted endometrial architecture associated with long-term use of tamoxifen.13 Ultrasonographic evaluation could have a higher cut-off
point of endometrial thickness, e.g. 9
mm, as a prompt for further
investigation. Hysteroscopy with biopsy
is preferable as the first line of
investigation in women taking tamoxifen who experience
postmenopausal bleeding.