This is a study comparing routine inclusion of the lower neck in initial CT thorax in patients with suspected lung cancer to not including it. The study aims to assess whether such an intervention reduces the number of invasive investigations required to achieve a final diagnosis and clinical stage and whether it improves the detection of cervical lymph nodes involvement by lung cancer.

Two practices currently exist regarding the role of lower neck CT in patients with suspected lung cancer but with little evidence for either. Routine lower neck CT is potentially associated with benefits of higher detection of neck lymphadenopathy leading to better staging, less invasive procedure with positive implications for patients experience and care. The potential harms are delay in diagnosis due to false positive findings and radiation exposure. There is limited evidence in this area so this study will potentially provide evidence to inform health policy decisions based on the risk benefit balance.

This is a retrospective comparative study to assess the real-life impact of routine lower neck CT on the diagnostic and staging work up of patients with suspected lung cancer across two cohorts.

Inclusion Criteria:

• Male or female age > 18 years
• Pathologically confirmed primary lung cancer
• Intrathoracic N2 and or N3 disease on CT defined as lymph node with short diameter > 10 mm

Exclusion Criteria:

• None

Patients initially seen with suspected lung cancer