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

Patients present daily about symptoms that could represent a new diagnosis of cancer. Some will present with easily recognised high risk symptoms such as dysphagia (5% likelihood of cancer if age >55 years), postmenopausal 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.As these symptoms are shared with benign, chronic, or self limiting conditions, the likelihood of cancer is low (mostly under 0.5%). The clinical consequence is that diagnosis of cancers with vague symptoms tend to be delayed: for example, about half of patients in England with multiple myeloma have to consult three or more times before referral, and over a third present to hospital as emergencies.Depending on the cancer site, reducing diagnostic delay can lead to improved survival, earlier stage at diagnosis, and improved quality of life. The answer to this diagnostic problem is not to investigate every low risk symptom at first consultation. 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 for exploring non-specific symptoms. However, taking time is not without hazard. Patients want to be reassured they do not have cancer. Theymay 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. Safety-netting has come to be regarded as “best practice” in relation to cancer diagnosis in non-specialist settings. Its aim is to ensure patients do not drop through the healthcare net but are monitored until symptoms are explained. We searched for evidence on how safety-netting can be done effectively in this context (see table 1⇓). What is the evidence of uncertainty?