A randomized prospective study comparing three techniques of conization: cold knife, laser, and LEEP

Three different techniques of cervical excision, cold knife conization, laser conization, and loop electrosurgical excisional procedure (LEEP) were prospectively compared with respect to treatment reliability, effectiveness, and safety. One hundred ten women with CIN1-2 and the squamnocolumnar junction not seen or CIN3 at the original diagnosis were randomized to treatment with cold knife conization (n = 37), laser conization (n = 37), or LEEP (n = 36). All three treatments were performed with local anesthesia on an outpatient basis. The mean age, histologic features (original and histology of the conization), endocervical involvement, and ectocervical extension were similar in the three groups. Blood loss and operating time were less (P < 0.01) in the LEEP group (5.4 cc of mean blood loss and 5.4 min mean duration time) than in the two other groups (16.2 cc and 14.0 min for cold knife conization, 21.5 cc and 15.6 min for laser conization). Volumes of the cones were evaluated: LEEP cones and laser cones were smaller than the cold knife cones (P < 0.001). During the pathological review of the conization, the major problem was difficulty in evaluating the lesion and its margins due to the coagulation induced by the laser or the LEEP. This alteration was present in 53% of the LEEP conization specimens and in 51% of the laser conization specimens. In the majority of the cases the coagulation was mild, but in one case (LEEP group) and in two cases (laser group) the conization was totally altered by the coagulation, and in 31% of all the LEEP conizations and 38% of all the laser conizations, evaluation of the entire margin was not possible due to coagulation of the tissue. During postoperative follow-up, the number of complications was the same in the three groups (two episodes of post-operative bleeding in each of the three groups). Two months after the treatment the cervix was evaluated: the os was diminished in the cold knife group compared to the two other groups and as a result, the squamnocolumnar junction was not seen in entirety in 50% of cold knife cases, in 19% of LEEP cases, and in 20% of laser cases. These results suggest that in our hands: (1) laser conization is relatively costly and time consuming and alters the tissues significantly, and (2) the choice between cold knife and LEEP is more difficult--cold knife gives a sample adequate for histological evaluation (including evaluation of the margins), while the LEEP procedure is technically easier and less time consuming but sometimes induces electrocautery artifact so that evaluation of the margins is not possible.