Have we dismissed ablative treatment too soon in colposcopy practice?

摘要

Sir, We thank Dr Cruickshank and Prof. Kitchener for their interest in our commentary. The paper by Bruinsma et al. supports the evidence from other controlled studies illustrated by the comprehensive meta-analysis published in the Lancet in 2006 demonstrating that ablative therapy does not appear to have adverse obstetric outcomes. The majority of studies evaluating these outcomes after loop excision compared with controls are underpowered but suggest adverse effects. Statistical pooling reduces the likelihood of types 1 and 2 statistical errors within individual studies and clearly demonstrates obstetric morbidity. The eight studies included within the meta-analysis used LLETZ for all types of transformation zone (TZ). Individual studies from Sadler et al. (New Zealand) and Samson et al. (Canada) have evaluated obstetric outcomes after more than 500 outpatient excisional treatments, thus fulfilling the power calculations suggested as necessary by Cruickshank and Kitchener. These two papers on their own suggest adverse obstetric outcomes and therefore must be considered as an important part of the evidence base for decision making in screening programmes. In this era of evidence-based medicine, quoting a single, early, underpowered study with equivocal results (by Cruickshank) is not representative of the growing evidence that LLETZ is associated with adverse outcomes. Tt is fundamental to modem clinical practice that all studies should be evaluated as part of a systematic review, whether they are UK or internationally based, when deciding on optimum practice within the NHS cervical screening programme.