Pap Testing as Primary Screening
HPV Vaccine and the Pap Test:
Are Both Necessary?
Like the pap test, the HPV vaccine is an important advancement in the fight against cervical cancer. It targets two high-risk strains of the virus that cause 70% of cervical cancers. Even with the vaccine, however, cancer can still develop due to strains that are not covered or due to other contributing factors. Because of this, routine pap testing will continue to play a vital role in women’s cervical healthcare.1
HPV high-risk types
Approximately 11,000 women are diagnosed with cervical cancer in the U.S. each year. It is the second most common type of cancer for women worldwide — but it is also the most preventable. Over 95% of cervical cancer cases are associated with HPV, of which 70% are attributable to the high-risk types HPV-16 and HPV-18.2,3 The remaining 30% of cases are associated with other strains of HPV.
The importance of continued pap testing
With the recent availability of the HPV vaccine for women ages 9 to 26, there is a need for patient education surrounding the importance of continuing pap tests even after getting the vaccine.3 The American College of Obstetricians and Gynecologists (ACOG) recommends that pap tests be routinely performed even in women who have been vaccinated.4
Increasing incidence of adenocarcinoma
Most cervical cancers (80% to 90%) are squamous cell cancers. Adenocarcinoma is the second most common type of cervical cancer, accounting for the remaining 10% to 20% of cases. Although the overall incidence of cervical cancer has decreased, a shift has occurred in the frequency of the subtypes — the proportion of adenocarcinoma has been increasing.
Recent studies indicate that the proportion of adenocarcinoma has doubled relative to squamous cell carcinoma, especially in young women.5-8 The reason for the recent increase is unclear; however, probable risk factors include history of uterine disease, sexual history, and HPV infection.
The ThinPrep Pap Test is the only pap test for which the FDA has approved labeling supported by multiple peer-reviewed publications reporting improved glandular disease detection.9-12
Advances in pap testing: the ThinPrep Imaging System
Since the introduction of the pap smear for cervical cancer testing, followed by liquid-based pap testing in the past decade, rates of cervical cancer incidence and mortality have dramatically reduced. And recently, advances with the ThinPrep Imaging System have raised disease detection standards to new levels.
1. Gardasil® product information.
2. Bosch FX, de Sanjose S. Human papillomavirus and cervical cancer-burden and assessment of causality. J Natl Cancer Inst Monogr. 2003;31:3-13.
3. Villa LL, Costa RLR, Petta CA, et al. Prophylactic quadrivalent human papillomavirus (types 6, 11, 16, and 18) LI virus-like particle vaccine in young women: A randomised double-blind placebo-controlled multicentre phase II efficacy trial. Lancet Oncol. 2005;6:271-8.
4. American College of Obstetricians and Gynecologists. Human papillomavirus vaccination: ACOG Committee Opinion No. 344, Obstet Gynecol. 2006;108:699-705.
5. Chan PG, Sung HY, Sawaya GF. Changes in cervical cancer incidence after three decades of screening US women less than 30 years old. Obstet Gynecol. 2003;102:765-73.
6. Liu S, Semenciw R, Mao Y. Cervical cancer: the increasing incidence of adenocarcinoma and adenosquamous carcinoma in younger women. CMAJ. 2001;164:1151-2.
7. Wang N, Emancipator SN, Rose P, et al. Histologic follow-up of atypical endocervical cells: liquid-based, thin-layer preparation vs. Conventional Pap smear. Acta Cytol. 2002;46:453-7.
8. Bai H, Sung CJ, Steinhoff MM. ThinPrep Pap Test promotes detection of glandular lesions of the endocervix. Diagn Cytopathol. 2000;23:19-22.
9. Carpenter AB, Davey DD. ThinPrep Pap Test: Performance biopsy follow-up in a university hospital. Cancer. 1999;87:105-12.
10. Guidos BJ, Selvaggi SM. Detection of endometrial adenocarcinoma with the ThinPrep Pap Test. Diagn Cytopathol. 2000;23:260-5.
11. Schorge JO, Hossein Saboorian M, Hynan L, et al. ThinPrep detection of endometrial adenocarcinoma: a retrospective cohort study. Cancer Cytopathol. 2002;96:338-43.
12. Ashfaq R, Gibbons D, Vela C, Saboorian MH, Iliya F. ThinPrep Pap Test accuracy for glandular disease. Acta Cytol. 1999;43:81-5.
Learn more about independent studies with the ThinPrep Pap Test and the ThinPrep Imaging System.