The Changing Role of Pathologists in the Age of Precision Medicine
Article Feb 07, 2018 | By Anna MacDonald, Science Writer for Technology Networks
Pathology Department at the Central Cancer Research Laboratories. Credit: G. Terry Sharrer, Ph.d. National Museum Of American History.
The role of pathologists in cancer care is evolving to bring pathologists to the centre of multidisciplinary collaborations, providing vital information to tumour boards about a patient’s cancer diagnosis and treatment options. Developments in diagnostic technology and the rise of precision medicine mean pathologists are more involved in clinical decisions than ever.
We spoke to Dr Philippe Taniere, Consultant Histopathologist/Molecular Pathology, and Dr Matthew Evans, Specialist Registrar at University Hospitals Birmingham, to learn how the role of pathologists is changing, what this means for oncologists and cancer patients, and some of the challenges these changes may present.
Anna MacDonald (AM): How does the role of today’s pathologist differ from 5, 10, or 20 years ago, and what do these changes mean for oncologists and patients?
Dr Philippe Taniere and Dr Matthew Evans (PT/ME): More than ever before, pathologists are increasingly involved in the clinical management of patients. In large part, this has evolved alongside developments in technologies and systems which allow this involvement.
Firstly, unlike in the past, diagnosis of tumours is made prior to their removal, owing to the new ability to acquire small tissue through modern imaging-guided technologies; this means that clinicians and pathologists alike have all the salient information up-front and can make more complex management decisions. This is tied to the fact that the number of therapeutic options has greatly expanded, and it may be the case even that surgery is not the most appropriate initial step.
Secondly, the range of tests which can be undertaken by pathologists on these very small samples has expanded. It includes the use of stains, immunohistochemical markers and molecular markers. This allows much more accurate prognostication and prediction of response to treatment than before. One of the best examples is the situation for patients presenting with advanced lung cancer: most patients can now have a small sample of tumour taken despite their frailty, which can allow foremost an accurate diagnosis of the type of tumour present, but also to assess the suitability of the patient for various available targeted therapies (EGFR mutation, ALK translocation, PD-L1 expression). The entire assessment can now be completed within a week and available for early discussion at tumour board meetings – a vital requirement for these very ill patients. Pathologists nowadays must integrate multiple different pieces of information derived from various tests, and correlate these with clinical information; thus, pathologists must now take an active role in clinical decision-making.
Thirdly, information provided by pathological assessment is far more detailed and clinically-guided than before. The information provided by pathologists is dynamically adapted based on the point of the patient’s management and what is required at a given time in the patient’s journey: the information which must be provided on a biopsy is different from that needed from a surgical specimen, which is in turn different from that needed on a biopsy of recurrent disease. In a very real sense, while pathologists do not physically see their patients, they now must follow up patients and be aware of what treatment they require at any given time in their management. This is increasingly important now that – thanks in part to these new developments – patients with cancer are living longer and longer.
All this means that pathologists are able to provide much more personalised and accurate information than ever before. This means that oncologists are empowered to provide their patients with the most appropriate treatments, and patients are able to benefit from this personalisation.
AM: Do pathologists now face any new challenges?
PT/ME: The first hurdle which pathologists must overcome is to become familiar with, and to be able to integrate the information derived from, the plethora of new and sophisticated techniques available which contribute to the depth of information accompanying the pathological diagnosis, including extensive sequencing and digital pathology. In achieving this, pathology departments must be more multidisciplinary than ever before: teams must consist both of medically-trained pathologists and of scientists from various backgrounds, including morphologists, geneticists, informaticians and bioinformaticians.
The challenge is to ensure that those new technologies are nonetheless regarded as being complementary techniques to classical pathology, and are not considered a replacement on the basis of expertise in a single technology. Ultimately, it is the morphological diagnosis which has the biggest impact on predicting prognosis and response to treatment in cancer, and technologies such as wider sequencing refine this. In the same vein, it remains absolutely necessary that the integration of data from all these sources be by a medically-trained pathologist, and translated into its clinical relevance, before being discussed with the clinical team at the tumour board meeting.
AM: How do you see the role of pathologists evolving in the future?
PT/ME: In general, pathologists will spend increasing amounts of time on each case in the future, and there will be a need for increasing specialisation of individual pathologists. It is likely that, as the amount of information coming from increasingly large numbers of sources continues to increase, pathologists will be spending more and more time on each case, integrating this into a complete, clinically-relevant report. Much of this will require the use of algorithmic analysis of the data to determine the best course of action for each individual patient. Developments in digital pathology will also allow more accurate and reproducible assessment of quantitative data.
Pathologists – equipped with both their pathological and clinical backgrounds – will have an increasingly important role to play in patient care, as long as laboratories remain well-resourced with both equipment and with staff.
You can watch Dr Taniere and other leading pathology figures speak more about the increasing importance of the pathologist in cancer care in this short film by Agilent: https://www.agilent.com/about/newsroom/videos/2017/fight-against-cancer.html
Dr Taniere and Dr Evans were speaking to Anna MacDonald, Science Writer for Technology Networks.
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