A cone biopsy is another means of diagnosing and treating abnormal cells of the cervix by surgical excision. Typically, these cells are pre-cancerous glandular cells of the endocervical canal called adenocarcinoma in-situ (ACIS). They are not cancerous but if left untreated, can develop into another type of cervix cancer called adenocarcinoma.
Like a LLETZ , a cone biopsy aims to remove the abnormal area of the cervix for diagnosis and/or treatment. It uses different instruments to allow for more precise excision because the lesion is often in the cervical canal and cannot be seen, even with a colposcope. It also generally removes a slightly larger amount of tissue and for this reason, is associated with slightly more risks, related to menstrual cycles and future pregnancy, than a LLETZ. These risks are always balanced against the risk of undertreatment or not removing enough tissue to make a diagnosis.
In younger women, particularly those who have not started or completed childbearing, a smaller cone specimen may be taken to preserve the length of the cervix and reduce the chance of pregnancy complications. Because the location of these cells up the canal makes it hard to visualise on examination, a sample (curette) of the remaining endocervical canal may also be taken at the time of the cone biopsy to ensure abnormal cells are not missed by the cone biopsy. This procedure does not carry any additional risks to those already associated with the cone.