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Atlas of visual inspection of the cervix with acetic acid for screening, triage, and assessment for treatment

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Steps to determine eligibility for ablative treatment Ė Principles of treating cervical precancerous lesions


Treatment of cervical precancer using cryotherapy (ablative technique):

Excision of the transformation zone using large loop excision of the transformation zone (LLETZ):

The basic principles of treatment of cervical intraepithelial neoplasia (CIN) are the following.

  • The decision about treatment may be based on the outcome of the screening test (all screen-positive women are treated) or on the colposcopy diagnosis (all women suspected to have high-grade CIN on colposcopy may be treated) or the histopathology diagnosis.
  • Whatever the decision-making process is, the treatment of cervical precancer involves either of the two types of technique: ablative techniques or excisional techniques.
  • The entire transformation zone undergoes HPV-induced clonal change and is at risk of developing CIN. Therefore, the whole transformation zone should be treated (either ablated or excised), irrespective of the size of the lesion.
  • High-grade CIN lesions often extend into the crypts present in the transformation zone. The depth of the crypts can be up to 5 mm. During ablative treatment, the tissue destruction must extend up to 7Ė8 mm to ensure complete clearance of disease. Similarly, during excisional treatment the specimen to be excised should be fashioned in such a way that the entire transformation zone, including the full length of the crypts, is removed.
  • CIN1 lesions detected on histology or colposcopy may not be treated, because they rarely progress to higher grades. Such low-grade lesions should be treated only if the lesions increase in size or in severity during follow-up, persist beyond 2 years, or are associated with high-grade cytological abnormalities, or when follow-up is not guaranteed.
  • CIN2 and CIN3 lesions should always be treated in women aged 30 years and older.
  • No treatment of CIN should be performed during pregnancy. Wait for 3 months after childbirth before recalling the patient for treatment.
To learn more about the different treatment techniques, access the Atlas of Colposcopy: Principles and Practice.


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