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Diagnostic Journeys in Prostate Cancer
Can prostate cancer, especially aggressive prostate cancers, be diagnosed earlier? This is the research question that a 3 year study, joint-funded by Cancer Research Wales and West Wales Prostate Support Group, seek to provide some answers for. Cancer patients in Wales generally tend to get diagnosed at a late stage, which is thought to be a significant factor in why survival rates in Wales lag behind other countries that have similar healthcare systems.
The issues surrounding late diagnosis are both complex and multi-factorial, and will vary depending on the cancer type. Delays in the diagnosis and treatment of cancers can occur at the level of the patient, where they may be unaware of symptoms,or may be too embarrassed or frightened to go to the GP; they may occur at the level of primary care, where a patient has to visit a GP several times before referral to secondary care; or they could arise in secondary care, where following the necessary scans, biopsies etc, a delay to diagnosis and start of treatment may occur.
The Challenge for Prostate Cancer
Each cancer presents a unique challenge with respect to early diagnosis, and prostate cancer is no different. Every year in the UK, there are over 40,000 new diagnoses of prostate cancer, with 2600 of those in Wales. Whilst the incidence has increased greatly in the past two decades, the number of men diagnosed with late stage disease has fallen. This, in part, has been attributed to early detection of prostate cancer due to increased use of the prostate specific antigen (PSA) test. The challenge for prostate cancer diagnosis is the ability to quickly diagnose and treat those cancers that are aggressive, whilst avoiding over-diagnosis and over-treatment in men whose disease may be clinically insignificant or of a more indolent nature.
What we do know is that prostate cancer has longer diagnostic journeys compared to other more common cancers. Symptoms of prostate cancer may develop over time and some patients experience symptoms up to one year prior to diagnosis; while others are without symptoms. Some patients who request, or receive, opportunistic PSA testing tend to have low risk disease. Unfortunately, however, to date there are no published studies reporting the complete and in-depth journey to diagnosis of prostate cancer patients.
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Most men with prostate cancer typically present with similar symptoms to those who have benign non-cancerous enlarged prostates, and the two conditions can co-exist. These symptoms include urinary frequency, including at night, hesitancy, erectile dysfunction and presence of red blood cells in the urine. Men with more extensive disease may present with other symptoms, for example, pathological fractures. Because of a lack of a clear pattern of symptoms, there have been efforts to develop screening programmes, predominantly based upon prostate specific antigen (PSA) readings. PSA is widely available, and PSA values over a certain threshold normally trigger further testing. However, PSA screening has not been shown to be effective or cost-effective in large-scale trials, mainly because it is a non-specific test. Screening can cause over-diagnosis and inadvertent harms caused by subsequent procedures, and therefore is not recommended. However, there are developments on the horizon that may lead to better screening tests in the future.
The diagnosis of prostate cancer is therefore predicated on the selection of men with certain symptoms in primary care for further investigation, and is likely to remain the case for the foreseeable future. The NICE referral guidelines were updated in 2015 and the revised guidelines contain a list of symptoms for who digital rectal examination (DRE) and a PSA should be considered. The evidence base that underpinned the guidelines was not of sufficient strength for this guidance to be stronger (i.e. mandating rather than suggesting). Once abnormalities in PSA or DRE (although this is a relatively unreliable test) are evident, referral using the relevant suspected cancer pathway is mandated. For patients who fall outside the mandate for investigation or referral (for example patients with low-risk or non-specific symptoms), the guideline recommends review within a particular timeframe, or seeing the patient again if new symptoms develop, symptoms recur, worsen or cause concern.
As it happens the guidelines, which are now in use in England and Wales, were only based upon five studies, four of which were not unselected primary care populations and the fifth was a primary care case control study which may have led to inflation of the test accuracy statistics (NICE). It has also been suggested that adherence to the previous NICE Cancer Referral guidelines was poor in Wales. There is some evidence of opportunistic screening of symptomless men in Wales (for example in routine blood taking for chronic disease monitoring), and similar happening elsewhere; this has the potential to harm. Also there is no current evidence, for the effectiveness of different safety-netting strategies for patients being monitored in primary care for suspected cancer.
Picture credit: Oncology Central
The Research Project
Importantly, the NICE guidelines recommend further research, including the need for studies of patient experience of symptoms and the experience of referral. This what the new joint-funded research project will aim to address. The project will seek to describe, in detail, the ways in which men with prostate cancer are diagnosed from their first experience of symptoms or blood testing, and to identify all the factors and influences that contribute to this diagnostic journey. This will be achieved by recruiting newly diagnosed prostate cancer patients and undertaking detailed surveys with them. Similar surveys will also be conducted with their GPs and their urologists. Using the information gained in these surveys, the researchers will design an interview study with prostate cancer patients and GPs.
The study will address a number of issues will and include; Adherence to NICE guidelines; Effectiveness of PSA and DRE in the diagnostic pathway; investigation of ‘non-qualifying’ patients; How often the key symptoms are seen in primary and secondary care, and how often these are due to ‘significant’ prostate cancer Pulling all this information together, the objective of the study will be to identify and generate best practice recommendations in the identification of men with symptoms for testing to ensure effective diagnosis of prostate cancer.
The research project will be undertaken by research scientists based at the North Wales Centre for Primary Care, at Bangor University. One of the UK’s leading departments for the investigation of early cancer diagnosis. The leaders of the study, Professor Clare Wilkinson and Professor Richard Neal, are both practicing GPs, as well as clinical academics who have earned a world renowned reputation in this field of research.
The post-doctoral researcher who will work on the project on a full time basis is Tania Seale, who as part of her PhD studies undertook exactly the same research for multiple myeloma. Tania presented the results of her PhD studies at a recent national conference for Early Cancer Diagnosis held in London at the end of February, and therefore is someone who is ideally positioned to undertake such as project for prostate cancer, as many of the methodologies will already have been established.
We very much look forward to seeing the results that this important research study will produce.