Future of Cytotechnology
Human papillomavirus (HPV) has become the main subject of study in the field of cervical cytology because it has been discovered to be the causative agent in the vast majority of premalignant and malignant lesions of the uterine cervix. High-risk HPV types (16, 18) are detected in 99 percent of cervical cancers, according to Eileen F. Dunn, MD, MPH, (et. al.) in the article, "Prevalence of HPV Infection Among Females in the United States." This discovery has led to new developments in the field of cervical cytology. The FDA has approved the use of HPV testing and, more recently, a prophylactic HPV vaccine. Cytotechnologists are also starting to be trained in the field of molecular diagnostics. Molecular diagnostics, a field in which the tests probe molecular structure and function in diseased tissues and biological fluids, is being introducted into the cytotechnology repertoire. This type of testing allows for the ability to identify or predict a disease based on an individual's genetic profile.
HPV testing, which is an example of molecular diagnostics, is now done in conjunction with liquid-based cytology. The HPV test works by investigating the patient's cervical cell DNA for low or high risk HPV DNA. Different companies use different HPV testing techniques. For example, Digene uses the "hybrid capture" test, while Ventana uses "Inform HPV," which is a DNA probe cocktail for HPV. It's important to note that HPV testing is not done alone, but as previously stated, in conjunction with liquid-based cytology. It's the combination of both that provides a nearly 100 percent negative predictive value, according to Diane D. Davey, MD, of the University of Kentucky Medical Center in her article, "Reflex Human Papillomavirus Testing: Leave the Cytology Interpretation Alone." One test cannot work without the other.
There have now been two prophylactic HPV vaccines developed, only one of which has been approved by the FDA. They are Gardasil (Merck & Co., Inc.) and Cervarix (GlaxoSmithKline), Gardasil is the vaccine approved by the FDA for females ages 11-18. It protects against four strains of HPV (two low risk- 6,11 and two high risk-16,18) and Cervarix protects against two strains of HPV (high risk-16,18). These four strains are the most common cancer-causing HPV strains. Many argue that there will be no need for cervical cytologic screening as the vaccine is being implemented. The facts speak against this argument. The vaccines protect against only four strains of HPV. There are many other strains of HPV, and if women who get vaccinated are not getting screened, they run the risk of developing cancer from the other carcinogenic types of HPV not present in the vaccine, according to Debbie Saslow, PhD, (et. al.) in "American Cancer Society Guideline for Human Papillomavirus (HPV) Vaccine Use To Prevent Cervical Cancer and Its Precursors." Also according to the article, screening will need to continue to protect women who will not get the vaccine and who are already infected prevaccination. Presently, the American Cancer Society states that it is critical that women, whether vaccinated or not, continue screening according to current early detection guidelines.
Another new development in cytotechnology is the imaging system. Some laboratories are now using this imaging system to aid in cytotechnologists' screening. The imaging system involves a computerized imager that pre-screens Pap slides and selects random fields of view on the slide that it deems necessary for review by a cytotechnologist. The cytotechnologist then reviews the pre-screened slides on a special automated microscope that moves the slide to show the cytotechnologist the selected fields of view. If abnormal cells are found, the cytotechnologist then screens the entire slide and marks abnormalities for review by the pathologist. The imaging system is not intended to replace cytotechnologists, but rather intended to aid in the sensitivity and specificity of the cytotechnologists' screening. It has been proven to be more accurate in the discovery of high grade lesions, and it allows for rapid screening by cytotechnologists. The imaging system is a promising part of cytotechnologists' future.
In conclusion, cytotechnologists have a promising future. Even with the new developments in cervical cytology, screening will still be required in aiding in the discovery and diagnosis of malignancy and disease of the uterine cervix. Along with this, screening will also still be required in non-gynecological cytologic evaluations, and there will be a need for cytotechnologists trained in molecular diagnostics. All of these things together provide for a bright future for cytotechnology.