Conservative treatment of microinvasive squamous cell carcinoma of the cervix stage IA1: Defining conization height to an optimal oncological outcome

OBJECTIVE: This paper searches an ideal cone height for stage definition and safe treatment of cervical microinvasive squamous carcinoma stage IA1 (MIC IA1), avoiding excessive cervix resection, favoring a future pregnancy. METHODS: A retrospective study was performed involving 562 women with MIC IA1, from 1985 to 2013, evaluating cone margin involvement, depth of stromal invasion, lymph vascular invasion, conization height, and residual uterine disease (RD). High-grade squamous lesions or worse detection was considered recurrence. Univariate and multivariate regression analyses were performed, including age, conization technique (CKC, cold-knife, or ETZ, excision of transformation zone), and pathological results. Conization height to provide negative margins and the risk of residual disease were analyzed. RESULTS: Conization was indicated by biopsy CIN2/3 in 293 cases. Definitive treatments were hysterectomy (69.8%), CKC (20.5%), and ETZ (9.7%). Recurrence rate was 5.5%, more frequent in older women (p = 0.030), and less frequent in the hysterectomy group (p = 0.023). Age ≥40 years, ETZ and conization height are independent risk factors for margin involvement. For ages <40 years, 10 mm cone height was associated with 68.6% Negative Predictive Value (NPV) for positive margins, while for 15 mm and 25 mm, the NPV was 75.8% and 96.2%, respectively. With negative margins, the NPV for RD varied from 85.7–92.3% for up to 24 mm cone height and 100% from 25 mm. CONCLUSION: Conization 10 mm height for women <40 years provided adequate staging for almost 70%, with 10% of RD and few recurrences. A personalized cone height and staging associated with conservative treatment are recommended.