Invasive cervical cancer following treatment of pre-invasive lesions: A potential theory based on a small case series.

Purpose: The aim of this study is to present a single department's experience on cervical cancer cases following previous excision of cervical intraepithelial neoplasia (CIN) and to discuss potential pathogenesis.

Methods: Nine cervical cancer cases meeting the inclusion criteria, with available pathological and follow-up data, were considered eligible for this study.

Results: The majority (7/9) have had clear excisional margins. The interval between initial treatment and cancer diagnosis ranged from 7 to 17 years. In all cases cancer diagnosis was "unexpected", as the prior cytological and/or colposcopic evaluation was not suggestive of significant cervical pathology. All cancers were squamous, and 5/9 at stage I.

Conclusion: The long interval between initial CIN treatment and final diagnosis as well as the normal post-treatment follow-up may suggest a 'de novo' underlying but 'hidden' carcinogenesis process. It might be that dysplastic cells entrapped within crypts (or normal metaplastic affected by the same predisposing factors) continue undergoing their evolution, undetectable by cytology and colposcopy until they invade stroma and surfaces (endo- and/or ectocervical) approximately a decade later. Heavy cauterisation of cervical crater produced post excision might be a potential culprit of this entrapment.