31st December 2024

Diagnosis of lung cancer

CXR is often the first-line investigation, but CT chest, abdomen and pelvis is the investigation of choice in all patients with suspected lung cancer. PET scan may also be done. Tissue to confirm the diagnosis may be obtained with endobronchial ultrasound (EBUS) or, if not accessible by EBUS, on CT-guided percutaneous biopsy or video-assisted thoracoscopic surgery (VATS).  Pleural fluid may additionally be aspirated and sent for cytology. Pleural tap results suggestive of malignancy are an exudate (protein >30 g/L) with high LDH, low pleural pH (<7.3) and low glucose (<3.4 mmol/l), and with lymphocytosis or blood in the sample.