Diagnosing cancer in older adults: a review of international guidelines

Problem

Early cancer detection and diagnosis is one of the most effective means we have to improve cancer survival. Primary care is an important setting for achieving this, as most people with cancer see their general practitioner with symptoms in the year before they are diagnosed. Adults aged over 65 account for two thirds of all new diagnoses. However, late diagnosis and emergency presentations remain predominant in this group. In addition, screening programs often have an upper age cut off between 65 and 75.

This systematic review of clinical practice guidelines (CPGs) aimed to assess recommendations for investigating suspected cancer symptoms in older adults. Focusing on CPGs from high income countries and the four most common cancers in the UK (breast, prostate, lung, and bowel cancer). We addressed the following: i) what the recommendations for referral for further investigations are; ii) the upper and lower age cut off thresholds for referral; iii) what evidence underpins those recommendations iv) what are the differences between countries in guideline recommendations.

Approach

MEDLINE, Embase and TRIP databases were systematically searched, from 1 May 2020 to October 2020 for guidelines on the assessment of patients with symptoms suggestive of lung, breast, prostate, or colorectal cancer. Known guideline databases, websites and references of related literature were searched. We included CPGs related to diagnosis in symptomatic primary care populations, published within the last 10 years and available in English.

Findings

The search yielded 1592 titles and abstracts. We identified 31 guidelines which covered the management of suspected cancer symptoms in primary care in nine countries (Europe, n = 14; Oceania, n = 4; and North America, n = 13). Preliminary analysis shows most of the CPGs use systematic reviews of existing CPGs and primary research to underpin guidance. Consequently, there is broad consensus between CPGs on which ‘red flag’ symptoms to investigate. However, the presence of age cut offs appear to be a distinguishing factor. There is variance across the different regions, in particular North America versus Europe; with prostate and colorectal cancer guidelines also more likely to provide age cut offs in recommendations for referral.

Consequences

This is the first systematic review of CPGs addressing recommendations in relation to age thresholds for investigating suspected cancer symptoms. The questions posed in this review are key in highlighting the dearth of evidence to support recommendations surrounding age cut offs in referral and investigation of suspected cancer symptoms. In doing this review, we will identify how current recommendations deal with cancer risk in older adults. We believe that it will lead to future research surrounding the interpretation of symptoms in a population group at higher risk. Full results will be presented at the conference.