This case demonstrates a pathology-proven upper esophageal squamous cell carcinoma with local invasion into the posterior wall of the trachea.

Early staging of oesophagal cancers is essential, but CT cannot differentiate between diseases categorized as T1, T2, or T3. The primary role of CT is identifying the loss of fat planes between the tumor and adjacent organs, which suggests the possibility of invasion, or frank invasion of adjacent structures (T4). Endoscopic ultrasound is the imaging modality of choice for T staging of the esophageal cancer.

Other signs that indicate potential direct invasion of esophageal cancer include:

• more than 90° of contact between the tumor and aorta

• displacement of adjacent structures

• indentation of adjacent structures, including the heart, posterior wall of the bronchus, or trachea, caused by the tumor; and

• pericardial thickening or effusion.

The use of multi-planar CT reformatting can also help to estimate tumor length more accurately.