A 62-year-old man with a 20-pack-year smoking history presents with persistent cough and haemoptysis for 3 weeks. Chest X-ray shows a 3 cm opacity in the left upper lobe with irregular margins. What is the most appropriate next step in management?

## Clinical Context A 62-year-old smoker with haemoptysis and a suspicious 3 cm opacity with irregular margins on CXR has a high pretest probability of lung malignancy. ## Imaging Algorithm for Suspected Lung Cancer **Key Point:** Any nodule >1 cm with suspicious features (irregular margins, spiculation, associated symptoms like haemoptysis) in a high-risk patient requires **CT chest with IV contrast** as the next step — not repeat CXR or sputum cytology. **High-Yield:** The standard workup for suspected lung cancer is: 1. **High-resolution CT chest with IV contrast** — defines nodule characteristics, mediastinal involvement, and excludes contralateral disease 2. **PET-CT** — performed simultaneously or immediately after CT for staging (detects metastases, lymph node involvement) 3. **Tissue diagnosis** — bronchoscopy, FNAC, or biopsy only *after* imaging is complete and staging is known ## Why CT + PET-CT First? | Feature | Benefit | |---------|----------| | **CT chest** | Characterizes nodule (size, margins, density), detects mediastinal/pleural involvement, identifies contralateral lesions | | **PET-CT** | Metabolic activity (SUV) helps differentiate malignancy from benign lesions; stages disease (M, N staging) | | **Timing** | Both should be done *before* invasive biopsy to guide biopsy site and plan treatment | **Clinical Pearl:** Haemoptysis + irregular margin + smoking history = **presumed malignancy until proven otherwise**. Imaging must precede tissue diagnosis to avoid sampling error and to stage disease. **Mnemonic: CPTB** — **C**T, **P**ET, **T**issue, **B**ronchoscopy (in that order for lung nodules). ## Why Not the Other Options? - **Sputum cytology & repeat CXR:** Low sensitivity (~40%) for peripheral nodules; delays diagnosis in a high-risk patient with haemoptysis. - **Immediate bronchoscopy:** Appropriate *after* CT/PET staging; bronchoscopy without imaging first risks sampling error and incomplete staging. - **Chest ultrasound:** Poor for lung parenchyma and mediastinal assessment; not standard for nodule characterization. [cite:Harrison 21e Ch 101]