LLETZ- Versus A Knife Conization

Results clearly favour the loop conization

Through an effective gynecological check-up, cell degeneration of the cervix uteri can be detected and treated even before the development of an invasive cervical carcinoma. The current standard treatment of a higher grade or low to moderate persistent neoplasm of the cervix uteri (CIN) represents the conization in which a conical shaped piece of tissue is removed from the cervical canal. Various conization techniques can be used. The original knife conization method has been replaced in the Western industrial countries, in most cases by the loop conization (“Large loop excision of the transformation zone“– LLETZ). Other methods such as laser conization, needle excision or ablative procedures are rarely used. With the LLETZ conization, the conus is not removed with a knife, but with a high frequency loop. A wide variety of studies showed that the LLETZ cone biopsy, due to the significantly lower peri- and postoperative complications, is superior to the knife conization. Nevertheless, in Austria the knife conization is still frequently performed.

Success rate and morbidity

With regards to the success rate of the conization, meaning the excision in healthy tissue the LLETZ conization and the knife conization can be regarded as equivalent. This is described by Martin-Hirsch et al. in a systematic Cochrane Review from 23 studies. The peri- and postoperative morbidity of the conization is, regardless of which operation technique, overall low. Nevertheless the knife conization compared to the LLETZ conization has a noticeable higher intra-operative loss of blood (79.1 +/- 74.6 ml vs. 3.3 +/- 2.8 ml, p < 0.01) and a significantly longer operation time (14 +/- 18.6 min vs. 2.8 +/- 2.9 min Oyesanya et al., 1993).

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