Conization is an operation on the cervix in which a cone of tissue (cone) is excised from the cervix (neck of the uterus) and then examined under a microscope.If abnormal cytological findings (Pap smear) were detectable during cancer screening, and despite colposcopy (examination of the vagina (vagina) and the cervix uteri (or collum (Latin. Collum for “neck“) or cervix) with a microscope with a magnification of 3.5 to 30 times) and targeted biopsy (tissue sample), further clarification is necessary, a conization is performed.
Indications (areas of application)
- CIN 1 (cervical intraepithelial neoplasia) – persistent for at least one year (recurrent and confirmed by cytological smears).
- CIN 2, CIN 3
- Suspicion of microinvasion
- Endocervical (located in the cervical canal) processes.
The procedure is usually performed under general anesthesia. It lasts about 20 minutes. At the beginning of the operation, the urinary bladder is emptied by means of a catheter. After setting the cervix with the specula, these are instruments that unfold the vagina, the cervix is fixed with two ball forceps and the portio surface (cervical surface) is stained with a 3% acetic acid solution, which represents the altered cells. The acetic acid causes protein in the cell nuclei to precipitate. Colposcopically, an acetic white area is thus found (e.g., cervical dysplasia). The Schiller’s iodine test is then performed. Healthy squamous epithelium turns dark brown, dysplastic cells show a yellow color. Depending on whether the altered cells are located on the surface of the cervix or in the cervical canal (cervical canal), it is decided whether the cone must be cut out very shallowly or somewhat deeper, into the cervical canal.There are different techniques of conization. Either the cone is cut out with a scalpel (knife conization), a laser (laser conization) or, as is most common today, with an electric snare (snare conization). Each method has advantages and disadvantages. However, because conization with the electric snare performs well in terms of complications, especially bleeding during and after the operation, and microscopic evaluation, it is the preferred method today. Since there may still be altered cells in the upper part of the cervical canal after conization, a cervical abrasion of the upper part of the cervix must be performed in any case. A scraping of the uterus is usually performed for safety reasons. If it is not possible to stop the bleeding by coagulation or sutures, it may be necessary to insert a tamponade, which is usually removed after one or two days. Overall, the operation is low-risk. The cone is then cut into many small slices and examined under the microscope. The pathologist thereby gains a spatial extension of the cell changes. This determines whether further treatment may be necessary or whether conization was already sufficient therapy. In about 85% of cases, the altered tissue is completely removed by conization. Early lesions are thus adequately treated if completely removed. In these mild cases, conization is already the therapy. Subsequently, short-term control examinations are required at approximately 3-month intervals. In all other cases, further clarification or therapy depends on what the microscopic result of conization is.
Possible complications
- The most common complications are post-operative bleeding either shortly after surgery or after 5-9 days. This is the time when the wound scab peels off. During this time, the patient should take it easy if possible. The wound is usually healed only after 4-6 weeks. Heavy physical strain should be avoided for this long. In addition, no sexual intercourse may take place during this time.
Finally, it should be mentioned that based on a meta-analysis, conization leads to a significant increase in miscarriages in the second trimester (period from the fourth to the sixth month; 1.6% versus 0.4%). Furthermore, ectopic pregnancies (pregnancies outside the uterine cavity) were also increased (1.6% versus 0.8%).
