How good is a chest CT scan at predicting the risk of pulmonary metastatic disease in patients with head and neck cancer? A retrospective observational study

Objectives: Our objectives were to assess whether a CT chest, when performed as part of initial staging investigations, is a robust method to identify lung metastases or synchronous primary lung cancers in patients with head and neck squamous cell and whether small nodules are likely to represent metastases in this group of patients. Design: Retrospective observational study performed between 1994 and 2005. Setting: Head and neck cancer department, Queen Elizabeth Hospital, Birmingham. Participants: All patients that were included had a new head and neck squamous cell carcinoma and underwent a CT chest as part of their staging investigation. Main outcome measures: The presence of lung masses on the initial screening CT of the chest as determined by the radiologist's report. The development of lung metastases or primary bronchogenic carcinoma in any patient. Results: Two hundred and thirty-nine patients met the inclusion criteria. 38 (16%) patients had a CT chest report for a lung malignancy (either metastatic or primary bronchogenic), 33 of these 38 (87%) patients actually had a lung malignancy. 32 (13%) patients had a CT chest report for a small nodule, three of these 32 (9%) patients were later diagnosed with a lung malignancy, all at a different site to the nodule. 169 (71%) patients had normal CT chest reports, of these 3 (2%) patients were later diagnosed with a lung malignancy. Conclusions: The CT chest is a useful screening tool but is not infallible. Small nodules should be taken seriously and monitored, but should not alter the initial decision as to the management of the patient.