The cytological detection of persistent cervical intraepithelial neoplasia after local ablative treatment: a comparison of sampling devices

Abstract

Objective To determine whether the cytological detection of persistent cervical intraepithelial neoplasia (CIN) after local ablative treatment is improved by the use of sampling devices other than the Ayre's spatula. Design A randomized controlled study. Setting Lothian Area Colposcopy Clinic. Subjects 856 patients who had received local therapy (CO2 laser or cold coagulation) for CIN II or III between 9 and 30 months earlier. Intervention Each patient had three consecutive cervical smears taken, one with the Ayre's spatula, one with either the Aylesbury, the Rocket or the Multispatula device, and finally one with the Cytobrush. The allocation of which spatula and the order of the first two was randomized. Each patient had a colposcopic examination immediately after the smears were taken. Main outcome measures A comparison of the detection of histologically proven persistent CIN by the Ayre's spatula with the detection of persistent disease by alternative sampling devices. Results Of the 856 patients 130 had histologically proven persistent CIN. Another 98 had suspicious findings on colposcopy but punch biopsies reported as histologically normal. Of the remaining patients with normal colposcopy 130 were randomly selected to form a control group. The cervical smears from these 358 women were reported. Significantly fewer Ayre’ s samples contained endocervical cells than Aylesbury samples (47%vs 59%, difference 12%; 95% CI 3%‐21%; P<0.1), Rocket samples (47%vs 67%; difference 20%, 95% CI; 12%‐32%; P<0.001) or Multispatula samples (47%vs 76%; difference 29%, 95% CI 19–38%; P<0.001). When punch biopsies contained CIN, dyskaryotic cells were seen in 10% of Ayre's samples, 4.3% of Aylesbury samples, 8.3% of Rocket samples, and in no smear taken with the Multispatula. Obtaining a third smear with the Cytobrush did not substantially improve the detection rate of dyskaryosis. Neither the order of use of the spatulas, the form of initial treatment nor the size of the transformation zone had any apparent effect on the cytological detection of persistent CIN. Conclusions We recommend that surveillance of patients who have received local ablative therapy for CIN should be by both cytology and colposcopy, and that cytological samples should be obtained using the Ayre's spatula.

Cervical intraepithelial neoplasia in patients with breast cancer: a cytological and colposcopic study

“…None of the cases of CIN in breast cancer patients was detected by cervical cytology, although the smears were taken under optimal conditions at colposcopy. This is a worrying finding but is consistent with our previous data (Hughes et al, 1989;Hughes et al, 1992) and with that of other authors (Richart & Barron, 1981;Giles et al, 1988). Giles et al (1988) report a cytological false negative rate of 58% for small lesions of CIN 1 and CIN 2 and postulate that this is due to the failure of these smaller lesions to exfoliate sufficient abnormal cells to enable accurate detection by cytology.…”

Authors' reply

“…1984) and our data would support this assertion. We found the Multispatula to be significantly better than the Ayre's spatula in this respect, with 76% of Multispatula samples from patients with treated cervical intraepithelial neoplasia (CIN) containing endocervical cells versus 47% of Ayre's samples (Hughes et al 1992). These figures are remarkably similar to those quoted by Pistofidis et al (1984), in relation to antenatal patients, who reported that 81 % of Multispatula…”

Meta‐analysis of the efficacy of cold coagulation as a treatment method for cervical intraepithelial neoplasia: a systematic review

“…In total, the 13 papers described the efficacy of cold coagulation as observed among 4569 women with CIN1‐3 . The remaining nine studies were not included in the meta‐analyses for the following reasons: cold coagulation was provided in combination with another treatment method ( n = 2); treatment was for non‐CIN cervical anomalies ( n = 1); data corresponded to safety/acceptability rather than efficacy ( n = 2); and insufficient data were provided for calculation of cure rates ( n = 4) …”

“…Over a median follow‐up period of 81 months, 1.2% displayed recurrent disease. Hughes and colleagues assessed persistence in 856 CIN2‐3 patients treated by either CO 2 laser, or cold coagulation . A total of 130 patients (15%) presented with persistent CIN over 9–30 months’ follow up.…”