A 62-year-old male heavy smoker presents with worsening cough and hemoptysis. Frontal chest radiography reveals superior and medial displacement of the minor fissure, elevation of the right pulmonary hilum, and a dense triangular opacity in the right upper hemithorax. The medial aspect of the displaced minor fissure demonstrates a convex inferior contour, while the lateral aspect forms a concave superior arc, creating an inverted 'S' shape ('Golden S sign of Steno').
What is the underlying cause of this specific radiographic contour?
- AChronic right upper lobe cavitary tuberculosis with secondary cicatricial atelectasis
- BLateral loculated malignant pleural effusion displacing the fissure superiorly
- CNormal anatomical variant of an accessory azygos fissure
- DRight upper lobe lobar collapse draped over a central obstructing endobronchial or hilar mass
- ETraumatic diaphragmatic rupture with herniation of the right hepatic lobe into the thorax
Rationale
The Golden S sign (or S-sign of Golden) is created on frontal chest radiographs when right upper lobe atelectasis collapses superiorly and medially (forming the concave lateral limb of the 'S') around a centrally obstructing hilar mass (which forms the convex inferior/medial limb of the 'S'). In an adult smoker, this appearance is virtually pathognomonic of an obstructing bronchogenic carcinoma (classically squamous cell carcinoma or small cell carcinoma) until proven otherwise.
Why not A?
Cicatricial atelectasis from tuberculosis causes retraction and upward displacement of the fissure, but lacks the central convex mass contour unless an active tuberculoma is present. Option B: A pleural effusion produces blunting of the costophrenic angle or a lateral meniscus, not an inverted S-shaped fissure. Option C: An azygos fissure is created by failure of normal migration of the azygos vein, appearing as a delicate, curved line terminating in a teardrop-shaped azygos vein at the right tracheobronchial angle. Option E: Diaphragmatic rupture causes bowel or liver herniation through the hemidiaphragm into the lower or mid-hemithorax, not an isolated RUL fissure deformation.
Volume 1, Chapter 2 (Thoracic), Section 2: Atelectasis Patterns, pp. 52–55