Identifying patients with undetected pancreatic cancer in primary care: an independent and external validation of QCancer(®) (Pancreas).

BACKGROUND: Despite its rarity, the prognosis of pancreatic cancer is very poor and it is a major cause of cancer mortality; being ranked fourth in the world, it has one of the worst survival rates of any cancer. AIM: To evaluate the performance of QCancer(®) (Pancreas) for predicting the absolute risk of pancreatic cancer in an independent UK cohort of patients, from general practice records. DESIGN AND SETTING: Prospective cohort study to evaluate the performance QCancer (Pancreas) prediction models in 364 practices from the UK, contributing to The Health Improvement Network (THIN) database. METHOD: Records were extracted from the THIN database for 2.15 million patients registered with a general practice surgery between 1 January 2000 and 30 June 2008, aged 30-84 years (3.74 million person-years), with 618 pancreatic cancer cases. Pancreatic cancer was defined as incident diagnosis of pancreatic cancer during the 2 years after study entry. RESULTS: The results from this independent and external validation of QCancer (Pancreas) demonstrated good performance data on a large cohort of general practice patients. QCancer (Pancreas) had very good discrimination properties, with areas under the receiver operating characteristic curve of 0.89 and 0.92 for females and males respectively. QCancer (Pancreas) explained 60% and 67% of the variation in females and males respectively. QCancer (Pancreas) over-predicted risk in both females and males, notably in older patients. CONCLUSION: QCancer (Pancreas) is potentially useful for identifying undetected cases of pancreatic cancer in primary care in the UK.