Kaitlin E. Sundling, MD, PhD
January 2019—The evolution of minimally invasive techniques and new diagnostic modalities have placed new demands on medical laboratories. Cytotechnologists find themselves uniquely poised to take on these new responsibilities, using their morphologic and analytical skills. In this article, I summarize potential roles for cytotechnologists that go beyond screening cytology slides to add value and improve quality in the clinical laboratory.
Prescreening slides for potentially rare microorganisms uses morphologic and locator skills. Groups at Massachusetts General Hospital and Mayo Clinic report cytotechnologist prescreening for microorganisms using immunohistochemical stains for H. pylori, AFB stains for mycobacterial organisms, and GMS stains for fungus.1,2 This prescreening has the potential to add value by increasing the sensitivity of detection for rare organisms as well as saving pathologists time.
Cytotechnologists’ rigorous approach to screening and attention to detail may help standardize the interpretation of prognostic and predictive immunohistochemical stains. For example, a Canadian group reports that cytotechnologist counting of Ki-67 index for gastrointestinal and pancreatic neuroendocrine tumors showed a significant time savings for pathologists and more accurate tumor grading.3 Similarly, cytotechnologists may be involved in HER2, estrogen receptor, and progesterone receptor quantification.1 The potential value of cytotechnologist pre-scoring of immunohistochemical stains could be extended to any biomarker with a clinical decision based on a quantitative result, such as PD-L1.
Digital pathology has the highest probability of success when trained microscopists review the whole slide images. In our laboratory, cytotechnologists perform the scanning, review the images, and re-scan slides that are poor quality. Cytotechnologists at Mayo Clinic additionally perform digital image analysis.1 Cytotechnologists can help ease the digital transition and provide needed quality assurance for these tools.
Evaluation of blood specimens for circulating tumor cells requires the use of strict morphologic criteria to evaluate multichannel fluorescence signals of rare tumor cells. Circulating tumor cell enumeration results are FDA cleared for breast, prostate, and colorectal cancers; however, they are most commonly used in the context of clinical trials. Kane and colleagues of Mayo Clinic report cytotechnologist screening of these data prior to pathologist review.1 It is expected that cytotechnologists’ involvement would improve the reproducibility of this test compared with pathologist review alone, although studies to this effect have not been identified.
Fluorescence in situ hybridization may also benefit from cytotechnologists’ morphologic skills and attention to detail. The group at Mayo Clinic reports cytotechnologist involvement in FISH for more than a decade, with applications ranging from urinary, pancreaticobiliary, esophageal, and pulmonary specimens.1 Cytotechnologists’ morphologic expertise allows them to better differentiate the DAPI nuclear signals of normal cells from abnormal cells, with the potential to achieve more accurate FISH results where normal cells are mixed with tumor cells.
Molecular HPV testing is a natural fit in the cytotechnology laboratory, and many cytotechnologists already perform this testing, including cytotechnologists in our laboratory. Cytotechnologist performance of other molecular testing is less common. ASCP-certified cytotechnologists are eligible to take the Technologist in Molecular Biology exam, and although this is not required to perform molecular testing, it may be a helpful credential for cytotechnologists who find an increasing niche in molecular testing.
Selection of tissue for send-out or in-house molecular testing places a logistical burden on surgical pathology and cytopathology. Even with efforts to prospectively indicate the best block for molecular testing at the time of the initial diagnosis, microscopic review may still be required if multiple specimens of different types are available. With additional training in histopathology as needed, cytotechnologists can also fulfill this role.1 This has the potential to reduce turnaround time for these tests, improve the quality of molecular results, and better conserve tissue for future tests.
Finally, cytotechnologists may also be ideally suited to perform translational research in anatomic pathology. Kopp and colleagues of Mayo Clinic report construction and interpretation of tissue microarrays by a collaborative group of cytopathologists and cytotechnologists.4 Many researchers outside the pathology department may lack morphologic expertise, and pathologists may lack the time to meet researchers’ needs. Thus, cytotechnologists can help bridge this gap while broadening their horizons beyond direct clinical work.
Although I have listed a number of specific applications suited to cytotechnologists’ skills, next-generation cytotechnology will not achieve its full potential through the acquisition of a specific set of skills or knowledge alone. This potential will be achieved by cytotechnologists building upon their scientific knowledge and laboratory expertise to become flexible laboratory professionals who will lead the way to the next improvements in diagnosis and treatment for our patients.
- Kane LE, Root RR, Voss JS, et al. Molecular diagnostics, personalized medicine, and the evolving role of the cytotechnologist: an institutional experience. Acta Cytol. 2012;56(6):678–685.
- Rego M, LoBuono C, Ring L, Smith H, Sweeney B, Wilbur D. Cytotechnologists accurately pre-screen special stains GMS/AFB on histologic or cytologic specimens and immunohistochemistry stains for H. pylori and Ki67 index on histologic specimens. J Am Soc Cytopathol. 2017;6(5):S57.
- Cottenden J, Filter ER, Cottreau J, et al. Validation of a cytotechnologist manual counting service for the Ki67 index in neuroendocrine tumors of the pancreas and gastrointestinal tract. Arch Pathol Lab Med. 2018;142(3):402–407.
- Kopp KJ, Passow MR, Del Rosario KM, et al. Cytotechnologists as coinvestigators in anatomical pathology research. Cancer Cytopathol. 2018;126(4):232–235.
Dr. Sundling is faculty director of the cytotechnology program, clinical instructor, and cytopathologist, University of Wisconsin School of Medicine and Public Health, Madison. She is a member of the CAP Cytopathology Committee.