The challenges of diagnosing pancreatic cancer: new pointers for clinicians

New biomarkers and access to imaging needed to diagnose pancreatic cancer earlier, Primary Care study finds.

No initial symptoms which differentiate between those diagnosed with and without pancreatic cancer were found in a new study from Dr Fiona Walter and colleagues at the Primary Care Unit, but key additional symptoms which may signal pancreatic cancer were identified.

Pancreatic cancer - the tenth most common cancer in the UK - is difficult to diagnose because the symptoms much more commonly arise from other benign or self-limiting conditions, and GPs face a considerable challenge to evaluate patients whilst making efficient use of hospital-based resources. There are currently no effective screening tools, and most cases of pancreatic cancer have already invaded local structures or metastasised by the time patients are diagnosed. Survival from pancreatic cancer is very poor, with less than 5% of patients alive at one year.

Shorter intervals between the time the patient first notices symptoms and the time that treatment is initiated are associated with better survival rates. Although pancreatic cancer patients may experience symptoms for many months before they ask for help, recent reports suggest that the time between symptom onset and treatment is longer than for other common cancers, such as lung or urological cancer.

Not all individuals interpret their initial symptoms as serious, and some attribute them to aging, lifestyle or other diseases. And even after they have asked for medical help, diagnosis in primary care may be complex, with delays arising when presentation is complicated by other illnesses, when referral is delayed or declined, or from false-negative investigation.

The new study looked at 391 patients with symptoms suggestive of pancreatic cancer and found only subtle differences in the impact of symptoms and patient factors on patient and health system intervals, highlighting the challenges of diagnostic testing and referral decisions for suspected pancreatic cancer.

“As GPs, we feel that pancreatic cancer is notoriously difficult to diagnose early, due to the insidious nature of the presenting symptoms. Indeed, in our combined years of General Practice, only one of us has diagnosed a case in primary care, with clinical suspicion arising only due to previous experience in gastro-intestinal medicine during training. There are few red flags in the presenting history of a patient with pancreatic cancer, but this study highlights possible amber warning signs that could facilitate earlier diagnosis. Future work could focus on developing guidelines for early diagnosis in primary care, which would require GPs to have direct access to urgent imaging,” explained Dr Kinnary Martin and Dr Alexandra Davidson from the General Practice Education Group in Cambridge.

Although no strong initial ‘alarm’ symptoms signalling pancreatic cancer were found, some clear implications for policy makers and clinicians emerged:

  • awareness campaigns could consider messages that reflect the importance of multiple, often intermittent, symptoms including decreased appetite and indigestion and systemic symptoms such as fatigue and weight loss
  • GPs could consider concurrent rather than sequential investigation with CT and gastroscopy for older people who present with indigestion that is atypical or associated with systemic symptoms
  • GPs could also have an increased awareness of the risk of pancreatic cancer among people diagnosed with diabetes
  • All health care professionals should remain alert to possible pancreatic cancer in people with back pain, and beware of misattributing potential symptoms of pancreatic cancer in those with self-reported anxiety and/or depression.

Dr Fiona Walter, Principal Researcher, Primary Care Cancer Research, said, 'We found that only people presenting with jaundice and decreased appetite as an initial symptom were investigated promptly. More targeted evaluation of people with suspicious symptoms could help to identify pancreatic cancer at an earlier stage, but it is clear that we also need other strategies for earlier diagnosis, including the development of diagnostic biomarkers and improved access to imaging.” 

More targeted evaluation of suspicious symptoms could help to identify pancreatic cancer at an earlier stage, when treatment is likely to deliver better results, but the study's authors conclude that other strategies for earlier diagnosis are also needed, including the development of diagnostic biomarkers and improved access to imaging.

Reference
Dr Fiona Walter, Katie Mills et al. Symptoms and patient factors associated with diagnostic intervals for pancreatic cancer (SYMPTOM pancreatic study): a prospective cohort study. The Lancet Gastroenterology and hepatology; 4 October 2016; DOI: 10.1016/S2468-1253(16)30079-6

30 Sep 2016