Can safety-netting improve cancer detection in patients with vague symptoms?

Patients present daily about symptoms that could represent a new diagnosis of cancer (1). Some will present with easily recognised high-risk symptoms such as dysphagia (5% likelihood of cancer if age >55 years), post-menopausal bleeding (4% likelihood if age >55 years), or haemoptysis (2% likelihood if age >40 years). But most will have vague or non-specific symptoms such as cough, fatigue, or abdominal pain (2-4). As these symptoms are shared with benign, chronic, or self-limiting conditions, the likelihood of cancer is low (mostly under 0.5%) (1). The clinical consequence is that diagnosis of cancers with vague symptoms tend to be delayed – for example, 51% of patients with multiple myeloma have to consult 3 or more times before referral (5) and 37% present to hospital as emergencies (6). Depending on the cancer site, reducing diagnostic delay can lead to improved survival, earlier-stage at diagnosis, and improved quality of life (7). The answer to this diagnostic problem is not to investigate every low-risk symptom at first consultation (8). Doctors have a responsibility to avoid causing unnecessary alarm and wasting scarce resources through over-investigation which may result in harm to the patient. Teasing out serious disease by following-up patients over time, with planned sequential investigation, is usually the best approach to exploring non-specific symptoms (9). However, taking time is not without hazard. Patients want to be reassured they do not have cancer (10). They may not re-consult to report unresolved symptoms, particularly if a repeat appointment is difficult to make or incurs a cost. If initial testing is driven by an incorrect preliminary diagnosis, resulting in reassuringly negative results, both patient and doctor may be reluctant to investigate further (11). Safety-netting has come to be regarded as “best practice” in relation to cancer diagnosis in non-specialist settings (12). Its aim is to ensure patients do not drop through the health-care net but are monitored until symptoms are explained. We searched for evidence on how safety netting can be done effectively in this context (see box 1) (13).