Gynaecology

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chapter 52 Gynaecology

ANATOMY AND DEVELOPMENT OF THE UTERINE CERVIX

The ectocervix is covered by pink squamous epithelium, which changes suddenly to the red columnar (glandular) epithelium of the endocervix at the squamocolumnar junction (SCJ) (Fig 52.2). The columnar epithelium is shorter in height than squamous epithelium and appears red because the thin cell layer allows the underlying blood vessels to be easily seen. Columnar epithelium invaginations into the cervical stroma form endocervical glands.

Before puberty, the squamocolumnar junction lies close to the external cervical os. As oestrogen levels rise after menarche and during pregnancy, the columnar epithelium everts further out onto the ectocervix to form an ‘ectropion’. Older terms including ‘erosion’ or ‘ulcer’ should not be used. Over time, the columnar epithelium exposed to the acid environment of the vagina is replaced by squamous epithelium (squamous metaplasia) and a new SCJ closer to the external os is formed. The area between the old and new SCJs where squamous metaplasia occurs is called the transformation zone. This is where most carcinogenesis occurs.

Newly formed immature metaplastic epithelium may develop into either:

As oestrogen levels fall at menopause, the cervix shrinks and the new SCJ moves back towards the external os and into the endocervical canal. The epithelium becomes thin, pale and atrophic, with subepithelial petechial haemorrhagic spots.

The external os is small and circular in nullipara or in women who have delivered only by caesarean section, and gaping and transverse in parous women. Nabothian cysts are retention cysts that develop when endocervical crypt openings are occluded by the overlying metaplastic squamous epithelium.

Endocervical polyps can form at any age after menarche, and arise from the endocervix. They may cause intermittent vaginal or postcoital bleeding, a discharge or, in older women, postmenopausal bleeding.

CERVICAL CANCER SCREENING

Routine screening:

Technique:

Cytological signs of dysplasia (cervical intraepithelial neoplasia, CIN) include nuclear enlargement, increased nuclear–cytoplasmic ratio, hyperchromasia, irregular chromatin distribution and increased mitotic figures.

Koilocytes are atypical cells with perinuclear cytoplasmic cavitation (halo) typical of HPV infection.

Histological signs of dysplasia (CIN) are categorised according to the proportion of the epithelium showing undifferentiated (dysplastic) cells:

Since 1990, a simplified two-grade histological system using the term ‘squamous intraepithelial lesion’ (SIL), known as The Bethesda System, has been used.

MANAGEMENT OF ABNORMAL SMEARS

The NHMRC booklet, ‘Screening to prevent cervical cancer: guidelines for the management of asymptomatic women with screen detected abnormalities’ (see Resources list) contains information on:

In general:

Abnormal cytology results frequently cause significant fear and anxiety for the woman, including:

An explanation of the procedure, reassurance and information to read will help allay her fears and allow her to relax during the procedure. There are no specific symptoms that indicate dysplasia.

HUMAN PAPILLOMAVIRUS INFECTION

Human papillomavirus (HPV) infection is common. Most infections are transient and resolve over 12–18 months. However, persistent infection with an oncogenic serotype of HPV increases the risk of invasive cancer. Types 16 and 18 cause 70% of cervical cancer cases, and types 31, 33, 35, 39, 45, 51, 52, 56, 58, 59 and 68 are also oncogenic. HPV types 6 and 11 cause 90% of genital warts.

Oncogenic HPV infection is also associated with:

TREATMENT OF CONFIRMED CERVICAL DYSPLASIA

Treatment options include:

After surgery, women should avoid strenuous exercise, vaginal douche, tampons or intercourse until the vaginal discharge has settled (usually 2–4 weeks). Recurrent lesions occur in 5–10% of women.

Treatment on the day of colposcopy without confirmatory biopsy may be considered in women who may fail to return for follow-up. This risks over-treatment of lesions.

Post-procedure follow-up depends on the severity of the lesion, the completeness of excision and other individual features.

Treatment can remove dysplasia but not cure HPV infection. HPV testing 12 months after treatment of a high-grade lesion may be useful as a ‘test of cure’.

Other measures include:

The few studies of HPV persistence showed a possible protective effect of fruits, vegetables, vitamins C and E, beta- and alpha-carotene, lycopene, luterin/zeaxanthin and cryptoxanthin.1 Evidence for a protective effect of cervical neoplasia was probable for folate, retinol and vitamin E, and possibly for vegetables, vitamins C and B12, alpha-carotene, beta-carotene, lycopene, lutein/zeaxanthin and cryptoxanthin. Evidence for an increased risk of cervical neoplasia associated with high blood homocysteine was probable, although the evidence is still inconclusive. Patients with an abnormal Pap smear should be advised to eat a diet rich in beta-carotene, vitamin C and folate (vitamin B9) from fruits and vegetables.

ABNORMAL UTERINE BLEEDING

A normal menstrual cycle occurs every 21–35 days, with bleeding for 2–7 days. Normal blood loss is 20–60 mL per period, with > 80 mL described as heavy.

The process of normal regular menstruation requires:

AETIOLOGY

Abnormal uterine bleeding is most common soon after menarche or in the years before menopause. It may be:

Medications associated with bleeding include anticoagulants, selective serotonin reuptake inhibitors, antipsychotics, corticosteroids, tamoxifen.

Medications that interact with the OCP/HRT, including liver enzyme inducers, antibiotics, anti-tuberculous drugs and antifungals, may also cause bleeding.

Herbal substances associated with bleeding include ginseng, ginkgo and soy supplements.

Causes of abnormal uterine bleeding are listed in Box 52.1.

MANAGEMENT

Management depends on the cause of bleeding, the woman’s plans for fertility and the impact that periods have on her life. In addition to bleeding, periods may involve dysmenorrhoea, sore breasts, mood disorder, migraines or an aggravation of pelvic symptoms.

Some women may request minimal treatment. Others may wish to avoid periods entirely. Different women may choose very different treatment options.

Teenagers presenting acutely with prolonged heavy bleeding (anovulatory cycles):

Consider options including:

Vitex agnus castus (chaste tree) 1000 mg daily.6 Although few randomised controlled trials (RCTs) exist, Vitex is commonly prescribed for menstrual irregularities, based on data collected by the German Commission E.7 Menstrual cycle irregularities due to hyperprolactinaemia, corpus luteum insufficiency, oligomenorrhoea and secondary amenorrhoea have been effectively treated with Vitex extract in open-label, uncontrolled studies

Ovulatory, regular, heavy periods:

Perimenopausal women with frequent irregular periods and variable flow:

DYSMENORRHOEA

Dysmenorrhoea can be considered ‘normal’ if:

MANAGEMENT

Management options for ‘normal period pain’ include:

ENDOMETRIOSIS

AETIOLOGY

The aetiology of endometriosis is unknown. It is increasing in prevalence. A tendency to develop endometriosis is inherited as a complex genetic trait influenced by environmental factors.13 Established lesions include inflammatory cells, fibrosis, neovascularisation and aberrant innervation. It has been associated with environmental toxins including organochlorines (polychlorinated biphenyls and dioxin-like compounds).14

Risk is increased with nulliparity and early menarche.15

TREATMENT OPTIONS

The treatments chosen will depend on the woman’s individual symptoms, preference, desire for fertility and coexistent conditions.

ADENOMYOSIS

Adenomyosis is the presence of endometrial glands and stroma in the myometrium with adjacent smooth muscle hyperplasia. It is generally diffuse but may form an adenomyoma locally. The aetiology is unknown, but it is more common in women with endometriosis.