The role of healthcare scientists in cancer diagnosis and management
Medical pathologists and healthcare scientists work collaboratively to improve pathology services for patients. Dr Jo Horne and Patrick Kumah describe the role of consultant scientists in the diagnosis and treatment of bowel cancer.
Every year over 40,000 cases of bowel cancer are diagnosed in the UK.1 Most diagnoses are made through diagnostic biopsies, taken at colonoscopy, where images are taken of the colon to detect any abnormalities. Biopsies (small samples of tissue) are taken to investigate symptoms that patients presented with, such as a change in bowel habit or bleeding. We usually receive biopsies from patients who are being investigated via the national bowel cancer screening programme.
Surgical resection specimens (larger pieces of diseased tissue) are examined, described and dissected by both medical histopathologists and healthcare scientists, with representative areas of individual specimens sampled and processed through the laboratory. The samples are stained to assess any significant changes in the structure of the tissue.
Consultant histopathologists, and increasingly, consultant scientists make the diagnosis. Consultant scientists have been eligible to train to report histopathology samples from the gastrointestinal tract (and other sites) since 2012. Our main role is to produce a histopathological report on the patient’s specimen. For biopsies, the report will contain diagnostic information and molecular test results.
Diagnosis is usually made on a glass side using a light microscope but, increasingly, digital pathology is being utilised for routine diagnostic histopathology. In digital pathology, images of the glass slide are created and captured with a scanning device to provide a high-resolution image that can be viewed on a computer screen or mobile device.
Cells that have grown normally have a uniform and organised appearance. By contrast, abnormal cells show a different range of features, a deeper colour on staining and a disorganised growth pattern. The bowel is made up of tissue layers, and when these abnormal cells grow in the wrong areas, this is known as cancer. To aid diagnosis, further investigations, using genetic testing or immunohistochemistry (a technique that makes proteins visible and helps to identify whether the patient has abnormal mismatch CASE repair genes), are performed. Mismatch repair genes are responsible for correcting any errors that are made when DNA is copied within a normal cell. Cells with abnormal mismatch repair genes build up many DNA mutations, which can lead to bowel cancer developing. Knowing whether there are abnormalities in the mismatch repair genes helps to exclude an inherited disorder called Lynch syndrome. It can also predict how the tumour will respond to any treatments that are planned for the patient.
Part of the role of healthcare scientists is to attend colorectal multidisciplinary team meetings (MDTs). In these meetings the team confirms the cancer diagnosis and sets out the patient’s individual treatment pathway. We review the histopathology reports beforehand. With increasing access to rapid molecular testing, we inform oncologists of any gene mutations that may indicate Lynch syndrome. All newly diagnosed cases of bowel cancer are assessed for Lynch syndrome. This is an inherited condition that puts people at a much higher risk of developing bowel cancer, as well as increasing the risk of other cancers including ovarian cancer, stomach cancer and womb cancer. Family members may have the condition, and they can be referred for genomic testing and counselling.
Attending MDTs allows scientists to fully integrate within clinical teams and has the added benefit of releasing time for medical histopathologists to undertake other, more complex work. The role of pathology in the diagnosis, staging and monitoring of colorectal cancer has increased greatly over the last few years. Scientists and pathologists are responsible for ensuring that the right tests are carried out to the highest standard on behalf of patients. As the workload continues to increase, there must be an appropriately trained and experienced clinical workforce, comprising both medical histopathologists and healthcare scientists.
Scientists are highly qualified and experienced individuals and, with appropriate training programmes and opportunities, in line with other healthcare professions, are in a perfect position to contribute to safely managing the increasing workload within histopathology. We can act as the conduit between the laboratory, MDT coordinators and clinicians, ensuring that cases are ready for discussion at MDT. We have the skills and knowledge to increase collaboration and integration between histopathology, molecular pathology departments and genomic testing laboratories, and to develop and quality assure new tests and ways of working, such as digital pathology or rapid molecular testing and interpretation.
The key now is to develop new, improved and widened workplace and academic training programmes for scientists in histopathology. We need to work towards more collaborative and integrated training programmes for medics and scientists, both nationally and within pathology networks. Undertaking this work, alongside increasing training places for medical histopathologists, is essential to safely sustain and improve histopathology services, ensuring that every person diagnosed with bowel cancer receives the right diagnosis and right treatment at the right time.
1. Cancer Research UK. Bowel cancer statistics.