Objective-To compare the outcomes in women with mild and moderate dysk
aryosis after increasing periods of surveillance and thereby to define
a rational protocol for managing such women. Design-Prospective study
with randomisation of women to one of four treatment groups, each wit
h a different period of surveillance; one group in which the women wer
e given immediate treatment and three other groups in which the women
were under surveillance for six, 12, and 24 months. Setting-A dedicate
d colposcopy clinic in Aberdeen, Scotland. Subjects-902 women who pres
ented with a mildly or moderately dyskaryotic smear for the first time
. Interventions-Cytological and colposcopic examinations at intervals
of six months until the allocated period of surveillance was completed
, at which time biopsy was performed. Women with severe dyskaryosis we
re withdrawn from surveillance and a biopsy was performed. Main outcom
e measures-The histological findings after punch biopsy or large loop
excision of the transformation zone, and the trends in cytological app
earances of serial cervical smears. Results-793 women completed the st
udy. In all, 769 women had an adequate final smear, of which 197 were
normal cytologically, 328 were still mildly or moderately dyskaryotic,
and 244 were severely dyskaryotic. Seventeen of the 67 (25%) women wi
th one repeat smear showing non-dyskaryosis had cervical intraepitheli
al neoplasia grade III compared with only one of the 31 (3%) women wit
h no dyskaryosis in four repeat cervical smears (P < 0.0001). None of
the women had invasive cancer. Of 158 women whose index smear showed m
ild dyskaryosis and who were allocated to the group under surveillance
for two years, only 40 had not defaulted or still had dyskaryotic sme
ars by the end of the two years. Conclusion-Cytological surveillance,
although safe, is not an efficient strategy for managing women with mi
ldly abnormal smears. Women with any degree of dyskaryosis in a smear
should be referred for colposcopy.