OC 09-06PRELIMINARY 48 MONTH EXIT RESULTS FROM THE HPV FOCAL CERVICAL CANCER SCREENING TRIAL

08. Screening methods
A. Coldman 1, D. Van Niekirk 2, M. Krajden 3, L. Smith 2, D. Cook 3, L. Gondara 2, R. Martin 4, S. Gavin 4, D. Quinlan 4, M. Lee 4, K. Ceballos 2, S. Peacock 1, E. Franco 5, G. Ogilvie 4.
1BC Cancer Research Centre (Canada), 2BC Cancer Agency (Canada), 3BC Centre for Disease Control (Canada), 4University of British Columbia (Canada), 5McGill University (Canada)

Background / Objectives

HPV FOCAL is a RCT conducted within the organized cervical cancer screening program in British Columbia (BC) Canada.  HPV FOCAL is comparing

the efficacy of high-risk HPV DNA testing, with Liquid Based Cytology (LBC) triage for HPV positives , to LBC testing with HPV triage for ASCUS,  

for the detection of  >CIN3 over 48 months. Presented are age stratified preliminary CIN detection rates at the 48 month exit. 


Methods

Over 18,000 women aged 25-65 were randomized into the Control and Intervention arms. Intervention Arm (IA):  Baseline HPV testing,

if HPV negative (HPV-) exit at 48 months with both HPV and LBC (co-testing). Control Arm (CA):  Baseline LBC testing, if LBC negative (NILM),

rescreened at 24 months with LBC and exit at 48 months with co-testing. This analysis includes 48 month exit data for women randomized

before July 1, 2011 with baseline screen negative (HPV- or NILM) results. Co-test results and detection rates of ≥CIN2 and ≥CIN3 are reported.


Results

There were 13091women (6538 Control and 6553 Intervention) randomized by July 1, 2011 with baseline negative results.

The exit co-test positivity rate was 6.0% for Control versus 4.6% for the Intervention (P<.001) arm. For women of all ages,

the >CIN2 rate was significantly higher in the Control than the Intervention arm (CA: 7.0/1000 [95%CI: 5.2, 9.4] vs.  

IA: 3.4 [95% CI: 2.1, 5.1], p-value 0.003). The CIN3 rate was also higher in the Control arm but not significant

(CA: 2.9 [95%CI: 1.8, 4.5] vs. IA: 1.4 [95%CI: 0.6, 2.6] p-value 0.06). The most >CIN2 detected in either arm was in women

25-29yrs at baseline (CA 32.2/1000 vs. 1A 14.7/1000), the lowest >50yrs (CA 3.7 vs IA 1.7). Across all ages, the

highest >CIN2 and CIN3 rates were in women HPV+ but LBC- at 48 months.


Conclusion

Four years after initial testing, more >CIN2 was identified in women who screened LBC negative at baseline than HPV negative,

illustrating the safety of the extended interval with a negative HPV result. The highest >CIN2 and CIN3 exit findings for women

of any age were in those with HPV+/NILM results, demonstrating that HPV, not cytology results are predictive of dysplasia.

These findings are highly informative for programs planning for HPV-based testing with an extended screening interval of 4 years. 


References