Article
A comparison between type 3 excision of the transformation zone by straight wire excision of the transformation zone (SWETZ) and large loop excision of the transformation zone (LLETZ): a randomized study
Registro en:
RUSSOMANO, Fábio. et al. A comparison between type 3 excision of the transformation zone by straight wire excision of the transformation zone (SWETZ) and large loop excision of the transformation zone (LLETZ): a randomized study. BMC womens health., London, v. 15, n. 12, 2015.
10.1186/s12905-015-0174-5
Autor
Russomano, Fábio Bastos
Tristao, Maria Aparecida Pereira
Côrtes, Renata
Camargo, Maria José de
Resumen
Background:The management of preinvasive cervical lesions has the objective to ensure the absence of invasive
lesions and to prevent progression to cancer. Excisional procedures have been preferred to treat these lesions as
they report the presence of unsuspected invasive lesions and the status of surgical margins, allowing inferring full
excision when such are free of disease. The purpose of this study is to determine whether Straight Wire Excision of
the Transformation Zone (SWETZ) is a better alternative than Large Loop Excision of the Transformation Zone
(LLETZ-cone) as a type 3 excision of the Transformation Zone (TZ) to reduce incomplete excision and concerning
other outcomes of surgical interest.
Method:Randomized controlled trial including women who needed type 3 excision of the TZ referred to a
colposcopy clinic after cytological screening between January 2008 thru December 2011. The interventions were
performed using local anesthesia and sedation in an inpatient basis by different experienced surgeons. The study
enrolled and randomized 164 women, of which 82 were allocated to each group. After exclusions, 78 remained in
SWETZ and 76 in LLETZ-cone groups for the analysis of outcomes of surgical interest and 52 and 54, respectively,
for the margins analysis.
Results:There was an even distribution between the groups after randomization and exclusions, concerning mean
age, parity, current smoking, prior cytological diagnosis and histopathological diagnosis obtained in cone specimen
even after exclusions. We observed significantly higher risk of compromised or damaged endocervical margin in
specimens resulting from the LLETZ-cone in relation to SWETZ (RR 1.72, 95% CI: 1.14 to 2.6), with an absolute risk
reduction (ARR) of 26.4% (95% CI: 8.1 to 44.8) for patients operated by SWETZ. The specimens obtained by SWETZ
showed less fragmentation (ARR = 19.8%, 95% CI: 10.3 - 29.3%), but the procedure took longer. There were
complications in 5.6% of the procedures, with no significant differences between the groups.Conclusion:This study showed a lower proportion of compromised or damaged endocervical surgical margin in
specimens resulting from SWETZ in relation to LLETZ-cone.SWETZ demonstrated to be more efficient than LLETZ-cone
concerning less fragmentation of the specimen obtained. However, it accounted for longer surgical time. Both techniques
showed morbidity.