What are the treatment options for different grades of Cervical Intraepithelial Neoplasia (CIN)?

Treatment Options for Cervical Intraepithelial Neoplasia (CIN)

For optimal patient outcomes regarding morbidity and mortality, treatment of CIN should be based on the grade of the lesion, with CIN-1 generally managed conservatively while CIN-2,3 requires more aggressive intervention.

CIN-1 Management

When Colposcopy is Satisfactory:

• Follow-up without treatment is the preferred approach for CIN-1 with satisfactory colposcopy 1
• Follow-up options include:
  • Repeat Pap tests at 6 and 12 months OR HPV DNA testing at 12 months 1
  • Refer to colposcopy if repeat cytology shows ASC or greater, or if high-risk HPV DNA positive 1
  • Return to annual screening after 2 negative cytology results or a negative HPV test 1
• A combination of repeat cytology and colposcopy at 12 months is an acceptable alternative follow-up approach 1
• The decision to treat persistent CIN-1 should be based on patient and provider preferences after discussing risks and benefits 1

When Treatment is Selected for CIN-1:

• Acceptable treatment modalities include:
  • Cryotherapy
  • Laser ablation
  • LEEP (Loop Electrosurgical Excision Procedure)
  • Electrofulguration
  • Cold coagulation 1
• Endocervical sampling is recommended before any ablative procedure 1
• Excisional modalities (LEEP, laser conization) are preferred for recurrent CIN-1 after previous ablative therapy 1

When Colposcopy is Unsatisfactory:

• A diagnostic excisional procedure (LEEP, laser conization, or cold-knife conization) is the preferred treatment 1
• Follow-up without treatment is acceptable only in special populations:
  • Pregnant women
  • Immunosuppressed women
  • Adolescents 1
• Ablative procedures are unacceptable for CIN-1 with unsatisfactory colposcopy 1

CIN-2,3 Management

Initial Management:

• Both excision and ablation are acceptable for CIN-2,3 with satisfactory colposcopy 1
• For recurrent CIN-2,3, excisional modalities are preferred 1
• Diagnostic excisional procedures are recommended for CIN-2,3 with unsatisfactory colposcopy 1
• Observation of CIN-2,3 with sequential cytology and colposcopy is unacceptable, except in special circumstances (e.g., pregnancy) 1
• Hysterectomy is unacceptable as primary therapy for CIN-2,3 1

Follow-up After Treatment:

• Follow-up using either cytology or combination of cytology and colposcopy at 4-6 month intervals until at least 3 cytologic results are negative 1
• During cytologic follow-up, the recommended threshold for referral to colposcopy is ASC or greater 1
• Annual cytology follow-up is recommended after 3 negative cytologic results 1
• HPV DNA testing at 12 months post-treatment has better sensitivity than cytology for detecting recurrence 1, 2

Special Considerations

• Natural history of CIN-1: Approximately 19% progress to CIN-2+ within 5 years, with higher risk in those with high-grade cytology or HPV16/18 positive status 3
• Natural history of CIN-2: About 43% regress without treatment, 35% persist, and 22% progress to carcinoma in situ or invasive cancer 1
• Treatment efficacy: No significant differences in treatment failures have been demonstrated between different surgical techniques 4
• Treatment selection: LLETZ (Large Loop Excision of the Transformation Zone) provides the most reliable specimens for histology with the least morbidity compared to other techniques 4
• Post-treatment monitoring: HPV testing at 12 months post-treatment has higher sensitivity than cytology for detecting recurrence 2, 5

Pitfalls to Avoid

• Avoid hysterectomy as primary treatment for CIN-1 or CIN-2,3 1
• Avoid ablative procedures for CIN-1 with unsatisfactory colposcopy 1
• Do not use podophyllin or podophyllin-related products on the cervix or vagina 1
• Do not perform repeat conization or hysterectomy based on a single positive HPV test 1
• Avoid under-treatment of CIN-2,3 as these lesions are more likely to persist or progress than to regress 1