CASE:
A 69-year-old female non-smoker presented with prolonged coughing with haemoptysis, loss of weight and loss of appetite. The initial CT scan revealed a heterogeneous mass in the lower lobe of the right lung with surrounding ‘crazy paving’ appearance (Figure 1A). The CT-guided biopsy revealed invasive moderately differentiated adenocarcinoma (eGFR positive) of the lung. She also developed right humeral pathological fracture secondary to bone metastasis. Her disease initially showed some improvement with Gefitinib, but progressed 6-months later. A repeat CT scan showed the whole aforementioned area of crazy paving appearance was completely replaced by solid tumour, confirming that the ‘crazy paving’ was tumour infiltration (Figure 1B).
Lung carcinoma usually appears as nodule (solid or subsolid) or mass on CT.1 Rarely, they may appear as ground glass opacity or consolidation.1 For lung carcinoma to demonstrate crazy paving as the CT appearances is rare despite its recognized existence and is usually caused by adenocarcinoma. Demonstration of crazy paving surrounding a sizable solid component of lung adenocarcinoma is even rarer. For lesion with solid and crazy paving changes, the solid component likely represent invasive portion of the neoplasm, whereas, the peripheral ‘crazy paving’ opacity may represent areas of lepidic growth.