What are screening tests?

Questions relating to prevention or early diagnosis of the ?female? cancers require the fullest discussion. Cancer of the genital organs or breast is the greatest concern, if not fear, of many patients attending their gynaecologist. Initially patients may worry that their presenting symptoms indicate that they already have cancer. The possible treatments for gynaecological problems usually include the administration of hormones and there can be anxiety that these may increase the risk of cancer developing.

The best form of treatment is prevention. Screening programmes are targeted at those most at risk of developing a disease with the objective of early diagnosis before the disease becomes too advanced for curative treatment.  

Pre-malignant changes of the cervix begin several years before invasive disease. Screening is designed to pick up the pre-malignant areas so that they can be destroyed before cancer occurs.

Cancer of the endometrium similarly passes through a pre-malignant phase (hyperplasia with severe atypia) before cancer develops.

A 42 year old lady presented with bleeding between her periods. Hysteroscopy with D and C (hysteroscopy D and C) were performed. The histopathology (11) showed endometrial cancer. Hysterectomy was performed and the histopathology showed residual hyperplasia only the tissue that had become malignant had been removed by the curettage. The prognosis for this lady is excellent.

Endometrial carcinoma is more common in those who have had relatively high oestrogen levels particularly if the endometrium has little protection from progesterone. Anovulation (menstrual cycles where no egg is released) is characterised by low progesterone levels. Obese women are more prone to high oestrogen levels and anovulation is one cause of heavy periods. Pre-malignant and malignant changes of the endometrium are very uncommon before the age of forty years. Endometrial sampling, usually by curettage, should be considered if periods are heavy in a lady over forty (hysteroscopy D and C). Irregular bleeding between periods (intermenstrual bleeding) may be a symptom of endometrial cancer and is another important indication for sampling the endometrium in the same age group and in women in their later thirties. Bleeding after the menopause, which is called postmenopausal bleeding, could be due to an endometrial cancer. After the menopause, the endometrial thickness should be 5 mm or less on ultrasound examination. Endometrial sampling is no longer mandatory in the investigation of postmenopausal bleeding provided ultrasound is reassuring.

Ovarian cancer is relatively silent so that the majority of ovarian cancers are diagnosed relatively late. Unlike the cervix and endometrium, the ovaries have no surface that is amenable to sampling. Ultrasound and tumour markers are under evaluation for early identification of ovarian cancer. If the disease could be identified early, the chance of successful treatment would be greatly enhanced.

In common with the ovaries, the breasts do not have a surface that can be sampled for identification of pre-malignant or malignant changes. You can examine your breasts for the presence of small lumps. Mammography and ultrasound of the breasts provide screening to identify early disease and thus improve the chance of cure. Some genes have been identified that are associated with increased risk for cancer of the breast and ovaries (Q32.40).