Diagnosis
Cervical cancer can be relatively straightforward to treat if the disease is diagnosed early, particularly at the pre-cancerous or CIN stage. The introduction of screening programmes has significantly reduced the incidence of cervical cancer, however the disease still claims 300,000 lives annually worldwide.
Cervical cancer diagnosis worldwide is a multi-step process based on expert assessment of cervical smears (screening) and then the cervix itself (referral) and involves a significant measure of subjectivity. Initial screening (known as a smear test or Pap test or LBC) involves taking a sample of cells from the cervix at the point of care. This sample is then transported to a cytology laboratory where it is examined by a skilled operator.
Those patients demonstrating a positive smear are then referred to a colposcopy clinic for a magnified visual examination/impression of the cervix by a colposcopist who seeks to discriminate between normal, pre-cancerous, and cancerous cells. The colposcopist’s presumed diagnosis of a pre-cancerous or cancerous lesion is in many cases then tested by a diagnostic biopsy. A biopsy is, today, the only way to confirm a presumed diagnosis of a pre-cancerous or cancerous lesion. Ethical and economic issues mean that it is not practical for every woman to have a diagnostic biopsy as a routine screen.
In 2005, about 3.5 million women between the ages of 25 and 60 were screened in England. 350,000 women had appointments in colposcopy clinics in the same year. In the USA 55 million smear tests are taken annually and of these 3.5 million women are referred for abnormal Pap tests or LBC results.