ENDOSCOPIC ULTRASONOGRAPHY OF SUPERFICIAL SQUAMOUS-CELL CARCINOMA OF THE ESOPHAGUS

Superficial squamous cell carcinomas of the oesophagus are defined as cancers confined to the mucosa or involving the submucosa but sparing the muscularis mucosae, with or without lymph node extension. Although lymph node involvement is rare (less than 5 %) in tumours confined to the mucosa, it is frequent (30 to 45 %) in tumours involving the submucosa, which have a prognosis similar to that of the usual obstructive tumours. Endoscopic ultrasonography is the most accurate examination (diagnostic accuracy greater than 95 %) to distinguish between superficial and advanced cancers. The absence of visualization of the muscularis mucosae with the currently available transducers limits the decision-making value of such a distinction except in the case of flat tumours in which the absence of ultrasonographically detectable parietal thickening indicates the presence of a cancer confined to the mucosa, with an excellent prognosis.