The Brock model for a lung nodule

A clinician enters details such as age, sex, family history of lung cancer, emphysema and characteristics seen on CT. Nodule size, location, type, number and edge shape can influence the calculated estimate. The output helps place an imaging finding into a management pathway; it does not show that cancer is present. A small nodule may still need comparison with earlier scans, while a more concerning pattern may lead to further imaging, specialist review or tissue sampling. The model is interpreted alongside symptoms, general health and scan quality.

Ask for the CT findings in plain language and clarify whether the model was appropriate for your type of nodule. Confirm whether older scans are available, because stability or growth can change the management decision. Follow the agreed plan for surveillance imaging, additional scanning or biopsy, and keep the appointment even if you feel well. If smoking is relevant, support to stop can benefit lung health, but a smoking history alone neither confirms nor excludes malignancy. Report new respiratory or general symptoms rather than waiting for scheduled imaging.

Contact your clinician promptly for coughing up blood, a persistent or changing cough, unexplained weight loss, worsening breathlessness, chest pain or a hoarse voice that does not settle. Lung cancer can present with these symptoms, but each also has other possible causes; the Brock estimate does not determine their cause. Seek emergency care for severe breathing difficulty, heavy bleeding from the airway, fainting, blue-grey lips or sudden intense chest pain. Urgency is based on the symptom and your condition, not on the model score.

Ask which features contributed most to the estimate, whether the nodule was compared with earlier imaging, and what uncertainty remains. Clarify the next test or scan, what change the team will look for, and how other health conditions affect the choice between monitoring and biopsy. If treatment is being discussed, confirm that the diagnosis and stage have been established separately from the Brock calculation.