EVALUATION OF THE APPRENTICESHIP OF ENDOS ONOGRAPHY - APPLICATION TO THE STAGING OF CANCER OF THE ESOPHAGUS AND THE CARDIA

Objectives. - Learning endosonography (EES) is known to be difficult, and the theory must be understood before performing EES routinely. The aim of the study was tb evaluate the diagnostic indexes of EES in the staging of cardio-oesophageal cancer after a period of theoretical ap prenticeship of EES and a learning period in a centre experienced in E ES since 1989. Methods. - Five observers, having never used EES, follo wed to EES examinations for a 3-6 month period. They then reviewed the standardized records of 29 patients with cardio-oesophageal cancer. T hey had to evaluate the degree of tumour infiltration within oesophage al wall and the site of metastatic lymph nodes. Results were compared with the diagnosis of 5 experienced senior endoscopists. Interobserver agreement was estimated with kappa statistics and considered excellen t for k greater than or equal to 0.75, good to moderate if 0.75 > k gr eater than or equal to 0.40, and poor if k < 0.40. Results. - Inter-ob server agreement was poor for the topographic diagnosis of lymph nodes (kappa index from - 0.09 to 0.33), lower to that of the 5 senior obse rvers (0.33 to 0.77). It was satisfactory for degree of tumour infiltr ation (T1 : k = 0.66, T2 : k = 0.58; T3: k = 0.56; T4 : k = 0.46). The individual sensitivities were weak according to lymph nodes site, but good for presence of lymph nodes (86 to 100 %), with a specificity of 40 to 73 %. Conclusions. - After theoretical training of EES, agreeme nt and diagnostic performances are good enough to diagnose pathologica l images (except for T4 tumors), and poor for localizing images in the mediastinum. This emphasizes the difficulties in learning echo-anatom y and gives useful guidelines for training programs in EES.