A study of diagnostic failure of loop conization in microinvasive carcinoma of the cervix

Objective. The aim of this study was to evaluate the specimen adequacy and the histological interpretation of loop conization for microinvasive cervic al carcinoma. Methods. We retrospectively reviewed the histopathological findings of the original cone specimens together with the final hysterectomy specimens in p atients with microinvasive carcinoma of the cervix, From 1990 to 1995, 63 c onsecutive patients with microinvasive carcinoma of the cervix were include d in the study, of which 35 patients underwent loop conization and 28 under went cold-knife conization. All patients had a hysterectomy. Results. The mean width, depth, and cone volume of the conization specimens were 2.44 cm, 2.15 cm, and 3.96 cm(3), respectively, in the loop group ver sus 2.3 cm, 2.35 cm, and 4.38 cm(3) in the cold-knife group. No significant differences were seen between the two groups. The application of loop coni zation was completed in a single slice in 27 patients (77.1%) and multiple slices by the loop in 8 (22.9%), in spite of the attempt to perform conizat ion in a one-pass application when possible. In assessing these cone specim ens microscopically, the rate of transection of tissue was significantly hi gher in the loop cone than in the cold-knife cone (17.1% versus 0%, P = 0.0 2). Because of transection of tissue and misorientation, pathologic determi nation of the depth and width of stromal invasion was undetermined in two l oop cone specimens compared with none in the cold-knife cones. Conclusion. Our study suggests that cold-knife conization is a preferred me thod in assessing microinvasive carcinoma of the cervix if multiple applica tions of loop conization are inevitable. (C) 1999 Academic Press.