Video monitoring of smear-taking at colposcopy: relationship to cytology.
OBJECTIVE
To investigate the reasons why cervical smears occasionally fail to reflect the underlying pathology in the cervix even when the smear is taken at colposcopy.


METHODS
A randomised study of three different smear-taking devices.


METHODS
A colposcopy clinic.


METHODS
Women attending the colposcopy clinic.


METHODS
A smear was taken from 172 nulliparous and 100 multiparous women at colposcopy and the procedure was monitored on a video-imaging system. The cytological findings were compared with the biopsy report in 147 nulliparous and 85 multiparous women.


METHODS
Accuracy of cytology and the effect of a range of variables on the accuracy of cytology.


RESULTS
Sampling of the transformation zone was incomplete in 15% of nulliparous women and 8% of multiparous women. Univariate analysis of a range of variables including parity, type of sampling devices, completeness of sampling of the transformation zone, size of the transformation zone, size of the lesion (aceto-white area) and location of the squamo-columnar junction showed that the accuracy of cytology was influenced by all these factors except for parity and smear-taking devices. Multivariate analysis showed that the location of the squamo-columnar junction, the size of the transformation zone area, the size of the aceto-white area and the ratio of the aceto-white area to the area of the transformation zone influenced the accuracy of cytology.


CONCLUSIONS
Women with large transformation zone areas (>30.03 mm(2)) and/or small aceto-white lesions (<7.01 mm(2)) are more likely to have an inaccurate cytology reports than women with small transformation zone and women with larger aceto-white areas. A ratio of the aceto-white area to the area of the transformation zone of 0.22 or less increases the risk of disagreement between the cytological and histological findings.
Department of Histopathology and Cytology, Imperial College School of Medicine at Hammersmith Hospital, Du Cane Road, London W12 0NN, UK.
Rana M
RM
Al-Awadhi
Elizabeth
E
Mansell
Swee
S
Chong
Carl
C
Chow
Albert
A
Singer
Dulcie V
DV
Coleman
D000328:Adult; D003127:Colposcopy / Q000379:methods*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D002583:Uterine Cervical Neoplasms / Q000473:pathology*; D014626:Vaginal Smears / Q000295:instrumentation / Q000379:methods*; D014741:Video Recording; D002578:Uterine Cervical Dysplasia / Q000473:pathology*