A retrospective study of cervical screening in women under 25 years (2005-2009)

Since 2003, when the age threshold of cervical screening in England has been raised from 20 to 25, there have been many calls to restore the previous starting age for cervical screening as there are concerns about the delaying of initiating cervical screening may result in an increase in the risk of cervical cancer. We conducted a retrospective study to analyse the safety of changing the starting age of cervical screening programme in England to the age of 25, by reviewing the cervical cytology performed in 426 women under 25 years in Bromley Borough of London, UK, between 2005 and 2009.

We conducted a retrospective analysis of 426 women under 25 years, who were referred with cervical smears taken at Bromley PCT's to the colposcopy clinic at Bromley Hospitals, South London Healthcare NHS Trust, over a 4-year period, between 2005 and 2009. The colposcopy findings and histology results were reviewed and analysed.

In our review, 44.80 % of smears showed mild dyskaryosis. 23 and 12 % showed moderate dyskaryosis and severe dyskaryosis, respectively. 11.2 % had borderline smear, and 0.2 % revealed glandular changes. On colposcopic examination, only 16.2 % (69) were reported as normal; however, 25.8, 20 % of the women were diagnosed with low and high grade abnormalities, respectively. 12 % (53) of the cases showed HPV-related changes, whereas no suspected malignancy was found. Colposcopic-directed cervical biopsy was obtained in 228 women (~54 %) depending on the colposcopic examination findings. The most histological finding was CIN I which constitutes 48 % (110) of all biopsies. However, 25 % (58) and 9 % (20) revealed CIN II and CIN III, respectively. The glandular changes noticed in only one case (0.44 %). The treatment was planned for 130 women, a significant proportion (30.5 %) of the 426 women who referred for colposcopy. The histological examination of the biopsies showed CIN in 91 % of the cases (115), 74.8 % (86) of them had CIN II (36) or CIN III (50). In addition, the glandular changes found in two cases (1.6 %). More importantly, there was one case diagnosed with micro-invasive cervical cancer (0.79 %) and this comprises 0.23 % of our sample.

In view of the size and the heterogeneity of our sample, it is difficult to recommend changing the starting age of the cervical screening programme. However, we strongly recommend to have a low threshold to offering cervical cytology to the women under 25 on clinical basis, particularly, after the recent introduction of HPV triage (outside the scope of this study), which will enable us to avoid the two main disadvantages of the early screening, namely over-diagnosis and over-treatment.