Evaluating cytology for the detection of invasive cervical cancer.

OBJECTIVE: To assess the sensitivity, the number needed to screen (NNS) and the positive predictive value (PPV) of cervical cytology for the diagnosis of cancer by age in a screening population. METHODS: A retrospective cohort of women with invasive cervical cancer nested within a census of cervical cytology. All (c. 8 million) women aged 20-64 years with cervical cytology (excluding tests after an earlier abnormality). From April 2007 to March 2010, 3372 women had cervical cancer diagnosed within 12 months of such cytology in England. The sensitivity of cervical cytology to cancer, NNS to detect one cancer and predictive values of cytology were calculated for various 'referral' thresholds. These were calculated for ages 20-24, 25-34, 35-49 and 50-64 years. RESULTS: The sensitivity of at least moderate dyskaryosis [equivalent to a high-grade squamous intraepithelial lesion (HSIL) or worse] for cancer of 89.4% [95% confidence interval (CI) 88.3-90.4%] in women offered screening was independent of age. At all ages, women with borderline-early recall or mild dyskaryosis on cytology (equivalent to ASC-US and LSIL, respectively, in the Bethesda system) had a similar risk of cervical cancer to the risk in all women tested. The PPV of severe dyskaryosis/?invasive and ?glandular neoplasia cytology (equivalent to squamous cell carcinoma and adenocarcinoma/adenocarcinoma in situ, respectively, in the Bethesda System) were 34% and 12%, respectively; the PPV of severe dyskaryosis (HSIL: severe dysplasia) was 4%. The NNS was lowest when the incidence of cervical cancer was highest, at ages 25-39 years, but the proportion of those with abnormal cytology who have cancer was also lowest in younger women. CONCLUSIONS: The PPV of at least severe dyskaryosis (HSIL: severe dysplasia) for cancer was 4-10% of women aged 25-64 years, justifying a 2-week referral to colposcopy and demonstrating the importance of failsafe monitoring for such patients. The sensitivity of cytology for cervical cancer was excellent across all age groups.

Characteristics and screening history of women diagnosed with cervical cancer aged 20-29 years.

BACKGROUND: There was concern that failure to screen women aged 20-24 years would increase the number of cancers or advanced cancers in women aged 20-29 years. We describe the characteristics of women diagnosed with cervical cancer in England aged 20-29 years and examine the association between the period of diagnosis, screening history and FIGO stage. METHODS: We used data on 1800 women diagnosed with cervical cancer between April 2007 and March 2012 at age 20-29 from the National Audit of Invasive Cervical Cancers. RESULTS: The majority of cancers (995, or 62% of those with known stage) were stage 1A. Cancer at age 20-24 years was rare (12% of those aged 20-29 years), when compared with age 25 (24%) and age 26-29 years (63%); however, cancers in women aged 20-24 years tended to be more advanced and were more often of a rare histological type. For 59% of women under age 30, the cervical cancer was screen detected, most of them (61%) as a result of their first screening test. A three-fold increase in the number of cancers diagnosed at age 25 years was seen since the start of the study period. CONCLUSION: Cervical cancer at age 20-24 years is rare. Most cancers in women under age 30 years are screen detected as microinvasive cancer.