An electrical scalpel conization versus Shimodaira-Taniguchi conization procedure for cervical intraepithelial neoplasia

The incidence of cervical intraepithelial neoplasia(CIN) among reproductive-aged women has increased in Japan. Cervical conization is commonly applied for local cervical treatment to preserve fertility. The Shimodaira-Taniguchi (S-T) conization procedure is widely used in Japan. S-T conization uses a high-frequency current and a triangular probe with a linear excision electrode to remove cervical tissue as a single informative specimen. However, alternative of an electrosurgical scalpel (ES) has the advantage of adjusting the surgical margin to the transformation zone in order to preserve the maximum amount of healthy cervical tissue with good hemostasis. The aim of this study is to retrospectively analyze data regarding surgical margin status, perioperative adverse events, cervical stenosis, and preterm birth between S-T and ES. Between January 2009 and December 2014, the medical records of 1166 patients who were diagnosed as CIN II, III, or stage 1a1 cervical cancer and who were treated with conization in 7 hospitals in Gunma Prefecture, Japan were enrolled for this retrospective study. The clinicopathological data was analyzed to statistically compare outcome between S-T and ES conization. There was no difference for age or post-operative follow-up period between ES and S-T treatments. However, positive surgical margins were significantly less frequent in patients who were treated with S-T than in those treated with ES, resulting in a reduced incidence of re-treatment for S-T in comparison with ES patients. In perioperative adverse events, S-T had more patients who were administered antibiotics. The incidence of preterm delivery and cervical stenosis did not differ significantly between the groups. We demonstrate here that S-T is an alternative procedure for cervical conization with a low risk of recurrence and acceptably low rate of adverse events such as cervical stenosis and preterm delivery. The results of this study can provide useful information for future management of patient with cervical intraepithelial neoplasia.