Digital pathology enables a pathologist to work with a digitized image created from a glass slide, providing the necessary technology and workflow for image acquisition and archival. Telepathology, which adds telecommunications technology to digital imagery, provides an opportunity to efficiently source (and route) cases based upon available resources, regardless of location. There is also a reduction in the expense of transporting slides and/or the overnight delivery of slides for secondary reads.
Digital pathology provides access to immunohistochemistry (IHC) and special stains, and facilitates remote frozen section diagnosis and rapid assessments of radiology directed biopsies. Telepathology facilitates consultations or second opinions, backup coverage for subspecialty pathologists, and secondary consultations from outside experts.
Making the Transition to Telepathology
Telepathology, a form of telemedicine, has several applications. A distant pathologist can provide a primary diagnosis to a site with no pathologist. A pathologist can request a second opinion from a distant colleague for a complex or ambiguous case, or an expert referral from a subspecialist. Other telepathology applications include quality assurance, education, and research. Telepathology is a rapidly growing segment of the telemedicine field.
Telepathology does not require the patient’s presence, which makes it one of the more remote forms of telemedicine. Teleradiology, telepathology’s close cousin, does not require the patient’s presence either, but radiologists’ transition to digital perpetuates their practice of working with digital images, whereas pathologists traditionally examine physical artifacts. The physical slide still retains legal value and must be examined and archived in most jurisdictions. The transition to telepathology thus adds extra steps to the process and involves laboratory technicians performing tasks previously devolved onto pathologists, such as manipulating large pieces of tissues and specimens.
Whole Slide Imaging
The College of American Pathologists has established guidelines for Validating Whole Slide Imaging for Diagnostic Purposes in Pathology, allowing pathologists to securely share their images and findings with colleagues and experts through email or over the web. They can also coordinate in real-time with specialists for secondary reads and consultations, regardless of their location or time zone. This opens up opportunities for pathologists to work from any location, at any time, that is most convenient for them. This, in turn, opens doors to work with facilities they may have an interest in, but don’t want to relocate to. It also allows pathologists to provide their skills to multiple remote facilities.
On April 12, 2017, the U.S. Food and Drug Administration (FDA) permitted marketing of the Philips IntelliSite Pathology Solution (PIPS), a whole slide imaging (WSI) system allowing for review and interpretation of digital surgical pathology slides prepared from biopsied tissue. This was the first time the FDA permitted the marketing of a WSI system for these purposes.
“The system enables pathologists to read tissue slides digitally in order to make diagnoses, rather than looking directly at a tissue sample mounted on a glass slide under a conventional light microscope,” said Alberto Gutierrez, Ph.D., Director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health. “Because the system digitizes slides that would otherwise be stored in physical files, it also provides a streamlined slide storage and retrieval system that may ultimately help make critical health information available to pathologists, other health care professionals and patients faster.”
Digital pathology is quickly becoming a proven, standard technology that significantly contributes to the reduction of laboratory expenses, improves operational efficiencies, increases productivity, and provides faster, more accurate diagnosis, treatment decisions, and patient care. Consider the movement of glass slides prior to digital pathology. The risk of shipping glass (ie: breakage, lost shipments, not receiving all of the slides back, etc.) along with the cost of actual shipments, not to mention the time involved—all equal high cost.
Healthcare facilities now have access to pathologists anytime and anywhere—giving them the ability to hire the best and the most affordable staff. Healthcare facilities with digital pathology are more competitive and attractive for pathologists’ services by allowing pathologists to work from their location of choice and on their timeframe. It also decreases the time to route cases and images to remote (or in-house) pathologists based upon availability and specialty. If additional specimen stains or views are required, the pathologist can order it from a lab who can then send the digital image back within hours (or less).
Digital pathology is transforming IHC. Instead of viewing and analyzing IHC slides under a microscope, digital pathology systems scan the stained slides in their entirety, storing the resulting whole-slide images in a digital format that can then be viewed and manipulated on a computer.
Digital Pathology in Cancer Diagnosis
Digital pathology aids in cancer diagnosis by providing faster access to the digital image and a greater ability to easily view all relevant case information, clinical findings, and any prior history (including comparing prior images). Tumor boards can better review and discuss complex, rare, interesting, and difficult cases. Access to specialists and experts around the globe leads to more accurate and faster cancer diagnosis and improved outcomes.
Digital pathology reduces the necessity of a pathologist to read a slide through a physical microscope, improving diagnostic capabilities by allowing the technology to zoom at various levels (while still allowing pathologists to monitor their progress through the entire specimen), quickly finding areas of interest, and allowing pathologists to annotate, measure, mark, and comment on the image itself. Pathologists can also capture regions of interest and thumbnail images from a digital slide which can be incorporated into the patient’s pathology report, along with the diagnosis, and be sent to the ordering, or treating, physician.
Patients benefit from access to specialists, experts, and the best diagnostic technology offered. The typical time from securing an appointment with a specialist once a patient or their physician identifies they need it through the evaluation, testing, reading, and receipt of a diagnosis typically ranges from four to twelve weeks. Digital pathology offers patients a faster diagnosis leading to a faster treatment plan. In addition, digital pathology allows patients to view and discuss their pathology findings directly with the pathologist over the internet.
