Background: The International Endocervical Adenocarcinoma Criteria and Classification (IECC) separated endocervical adenocarcinomas into human papillomavirus (HPV) associated (HPVA) and non–HPV-associated (NHPVA) categories by morphology alone. Our primary objective was to assess the accuracy of HPV prediction by the IECC system compared to p16 immunohistochemistry and HPV RNA in-situ hybridization (RISH). Our secondary goal was to directly compare p16 and HPV RISH concordance. Methods: Cases were classified by IECC and stained for p16 and HPV RISH on tissue microarray, with discordant p16/HPV RISH cases re-stained on whole tissue sections. Remaining discordant cases (p16/HPV, IECC/p16, IECC/HPV discordances) were re-reviewed by the original pathologists (n = 3) and external expert pathologists (n = 2) blinded to the p16 and HPV RISH results. Final IECC diagnosis was assigned upon independent agreement between all reviewers. Results: One hundred and eleven endocervical adenocarcinomas were classified originally into 94 HPVA and 17 NHPVA cases. p16 and HPV RISH was concordant in 108/111 cases (97%) independent of the IECC. HPV RISH and p16 was concordant with IECC in 103/111 (93%) and 106/111 (95%), respectively. After expert review, concordance improved to 107/111 (96%) for HPV RISH. After review of the eight discordant cases, one remained as HPVA, four were reclassified to NHPVA from HPVA, two were unclassifiable, and one possibly represented a mixed usual and gastric-type adenocarcinoma. Conclusions p16 and HPV RISH have excellent concordance in endocervical adenocarcinomas, and IECC can predict HPV status in most cases. Focal apical mitoses and apoptotic debris on original review led to the misclassification of several NHPVA as HPVA.

INTRODUCTIONA retrospective observational study was performed to evaluate the effectiveness of CervicalScreen Singapore (CSS), a National Cervical Cancer Screening Programme.

METHODSNational trends on incidence, mortality of cervical cancer and carcinoma in situ of the cervix before and after the launch of CSS were examined. Linear regression was used to calculate the average annual percentage change in age-standardised incidence and mortality rates. We also examined the operational measures of CSS, such as the women who joined the CSS programme and the diagnostic accuracy of Pap smears. The study was confined to women who consented to join CSS at government-funded polyclinics.

RESULTSNationally, there was a greater decline in the age-standardised incidence and mortality rates in the period 2004-2008 as compared to the period 1987-2003. Under CSS, a total of 99,759 Pap smears were performed on 81,087 women in the period 2004-2008. However, the number of first screens decreased from 18,434 in 2004 to 11,624 in 2008. Among women aged 25-69 years who had their first Pap smear screening and who were recommended for routine rescreen in three years, 10% had a subsequent rescreen within three years. Overall, the CSS programme was able to detect 0.37 invasive cancers per 1,000 screens in women aged 25-69 years.

CONCLUSIONThe CSS programme has contributed to a decline in the mortality and incidence of cervical cancer in Singapore. However, the challenges of increasing the screening uptake among eligible women need to be addressed.

Adult ; Age Factors ; Aged ; Early Detection of Cancer ; methods ; Female ; Humans ; Incidence ; Mass Screening ; methods ; Middle Aged ; Papanicolaou Test ; Registries ; Retrospective Studies ; Singapore ; Uterine Cervical Neoplasms ; diagnosis ; epidemiology ; prevention & control ; Vaginal Smears