GYNAECOLOGICAL CANCER

Cervical Cancer

Epidemiology

The incidence of cervical cancer is decreasing in the UK as a result of regular cervical screening. The incidence has fallen since 1989 when systematic screening was introduced and this disease now affects 2000 women in England and Wales each year. It mainly affects women in the 30 to 65 year old age group. A considerable amount is known about how cervical cancer develops. The process is usually quite a long one covering many years. Initially, a women is infected with certain types of the human papiloma virus (HPV). It is very common to be infected with HPV and a vast majority of women have no problems subsequently. Their body fights the infection and eradicates it and they become immune to further infections. However, there is a group of women who are not able to adequately fight HPV and they then develop pre cancerous cells on the cervix, these cells can usually be detected by cervical smears and it is these abnormalities that screening is designed to detect. These pre cancerous cells are called cervical intraepithelial neoplasia (CIN). CIN can be present for many years before developing into anything more severe. In fact, the vast majority of patients with CIN would not develop cervical cancer if they went untreated. However, if the CIN is undetected, usually for many years, then this can progress in about 30% of women to develop into invasive cancer of the cervix.

Other factors such as young age at the time of first intercourse, multiple sexual partners, smoking and the oral contraceptive pill have been associated with an increased chance of developing cervical cancer. However, the majority of women developing cervical cancer do not necessarily have any of these other possible risk factors.

Pathology

Approximately 85% of cervical cancers develop from the cells that are on the surface of the cervix. This results in a squamous cell cancer. The other 15% of cervical cancers develop from the columnar epithelium which lines the inside of the cervix resulting in an adeno carcinoma of the cervix. Squamous cell carcinomas and adeno carcinomas are treated in exactly the same way.

Presentation

A significant number of patients with cervical cancer will be detected during their routine cervical smear test. However, patients may present with abnormal irregular bleeding, especially after intercourse, or bleeding after the menopause. They may notice a smelly vaginal discharge or occasionally present with pain. On examination, a very small cervical cancer may not be visible to the naked eye, it may only be seen with a colposcopy examination or by taking a biopsy. The international organisation which classifies cervical cancers (FIGO) state that anyone with a cervical cancer should have an examination under anaesthetic, an examination of their bladder, an examination of the bowel (if necessary) and a scan of their chest and kidneys. All of these investigations can be utilised to determine exactly how large the tumour is and whether the tumour has spread to the surrounding tissues or to the lymph nodes of the pelvis. All patients will have an MRI scan which is the most accurate way of looking at the tumour.

Treatment

Early cervical cancers can be treated with surgery. If the tumour is microscopic then it may be possible to remove it with a cone shaped biopsy of the cervix. Tumours that are smaller than 4cm and confined to the cervix will usually be treated with a radical hysterectomy. This is an operation which removes the uterus and the tissue to the side of the uterus which is called the parametrium. It also removes the upper one third of the vagina and the pelvic lymph nodes. It may or may not be necessary to remove the ovaries at the same time. A small tumour of the cervix which does not spread to the lymph nodes, which is treated by a radical hysterectomy stands a 95% chance of being cured.

Larger tumours of the cervix are usually treated with a combination of chemotherapy and radiotherapy. This treatment is just as effective as surgery in curing early stage cervical cancer. Radiotherapy is usually a five week course of external beam radiotherapy together with a further dose of internal radiotherapy at the end. A small dose of cisplatin chemotherapy is usually given at the beginning, half way through, and at the end of this treatment.

Follow-up

Once treatment is completed then patients are usually required to attend for follow-up examinations every three months for two years in the first instance. The chances of recurrent disease are very much decreased after two years.