Alberta revises its cervical cancer screening guideline

Alberta has revised its Cervical Cancer Screening Clinical Practice Guideline (CPG) based on new technologies and epidemiologic evidence from Alberta and internationally. Led by Toward Optimized Practice (TOP), the revised guideline recommends:

• For most women, an extension to the Pap test screening interval from annually to every three years (following three negative Pap tests completed at least 12 months apart)
• Beginning Pap test screening for cervical cancer at age 21 or approximately three years after first intimate sexual activity, whichever occurs later

TOP, a tri-laterally sponsored program (supported by the Alberta Medical Association, Alberta Health and Wellness, Alberta Health Services and The College of Physicians and Surgeons), has the provincial mandate to develop, maintain and distribute Alberta's CPGs.

The changes to the Cervical Cancer Screening CPG resulted from the work of a multi-disciplinary expert committee led by TOP and made up of physicians and healthcare experts. It was the task of this committee to review the literature, along with new and existing data, and establish a Clinical Practice Guideline based on the evidence. The aim of this revised CPG is to optimize Pap testing in Alberta and decrease invasive cancer and deaths from this preventable disease, while minimizing screening risks.

Since the previous cervical cancer guidelines were written, new and improved lab technologies for reading Pap tests have been developed. Pap test guidelines have been changed to reflect these advances and help make sure women in Alberta benefit from cervical screening and avoid unnecessary tests. All other provinces across Canada have moved away from annual screening. Dr. Verna Mai, Chair of the Screening Action Group for the Canadian Partnership Against Cancer said, "The new guideline is evidence-based and is aligned with cervical screening guidelines followed in other provinces in Canada. It should be a welcome change for women as there will be fewer Pap tests needed for women who have repeated normal results."

There is also a new understanding about how cervical cancer develops. It is now known that:

• Most cervical cell changes are caused by infections with certain types of the human papillomavirus (HPV)
• These types of HPV are spread by sexual contact
• HPV is so common and spreads so easily that over 70% of people will get HPV in their lifetime
• Most people are not aware when they have HPV because most often there are no symptoms
• The immune system will usually clear the HPV within 2 years
• When the virus does not clear, it can cause cell changes that may lead to cervical cancer. These changes develop slowly over many years
• By getting Pap tests at least once every three years, cervical cell changes can be found early and if needed, treated so that cancer does not develop

Although the previous Alberta Pap test guidelines recommended that testing begin at 18 years for women who had ever had sexual intercourse, cervical cancer is extremely rare in women younger than 21 years. It is rare in this age group because it takes many years for cervical cell changes to develop into cancer, beginning with a persistent HPV infection. Many women will have a HPV infection soon after becoming sexually active, but the vast majority of these infections clear up on their own within 1-2 years. By waiting until age 21 to begin Pap testing, or 3 years after becoming sexually active, whichever is later, almost all important cervical cell changes will be found before they progress to cancer. This will greatly reduce the detection of cervical changes that would never progress and will reduce the anxiety for women and follow-up testing that go along with it. Women younger than 21 will still need regular visits with their healthcare providers for other health issues and to learn how to protect themselves from HPV and other sexually transmitted infections.

"The change in screening frequency from every year to every three years for most women with a history of normal Pap tests will ensure women receive the appropriate interval of screening, while not being over screened. Failure to be screened and being under screened are the major risk factors for cervical cancer in Alberta so it's very important that all women get screened. Women should discuss their previous Pap test results and other health issues with their primary care provider to determine what's best for them. It is anticipated this new guideline will help Alberta women get the most out of Pap testing, "says Dr June Bergman, Family Physician and co-chair, Cervical Cancer Screening Guideline Committee.

Additional information can be found at: www.screeningforlife.ca and www.topalbertadoctors.org