ABSTRACT
OBJECTIVE: To quantify the risk of residual invasion when cervical conization reveals microinvasive squamous carcinoma and to determine whether any factors affect this risk. METHODS: We reviewed the charts and histopathology slides of 87 women who underwent a conization that contained microinvasive squamous carcinoma, followed by either a repeat conization or hysterectomy. Depth of invasion, number of invasive foci, and status of the internal margin and post-conization endocervical curettage (ECC) were assessed. The findings were correlated with the presence of residual invasion. RESULTS: Significant predictors of residual invasion included status of the internal margin (residual invasion present in 22% of women with an involved margin versus 3% with a negative margin; P < .03) and the combined status of the internal margin and post-conization ECC (residual invasion in 4% of patients if both negative, 13% if one positive, and 33% if both positive; P < .015). Depth of invasion and number of invasive foci in the conization specimen were not significant. The power of this study to detect a 25% difference in the risk of residual invasion was 73% for depth of invasion and 75% for number of invasive foci. CONCLUSION: Women with microinvasive squamous carcinoma in a conization specimen in which both the internal conization margin and post-conization ECC are negative have a low risk of residual invasion and are candidates for follow-up or simple hysterectomy. If either the internal margin or the post-conization ECC contains dysplasia or carcinoma, the risk of residual invasion is high and warrants repeat conization before definitive treatment planning.
