Background and study aims: The macroscopic appearance of early gastric cancers, classified according to the Japanese criteria, has been shown to be an important prognostic factor for local endoscopic therapy. No prospective data about the distribution of macroscopic types and their location in early Barrett's neoplasia are available, however. The present study was conducted to evaluate the clinical applicability of this macroscopic classification and to analyze the relative proportions of the different gross types in early Barrett's neoplasms and the correlation between the macroscopic classification and the stage or grade of differentiation.
Patients and methods: A total of 344 patients with 380 Barrett's neoplastic lesions who were referred between October 1996 and September 2005 for endoscopic therapy of early Barrett's high-grade intraepithelial neoplasia and carcinoma were prospectively included in the study. Routine endoscopy prior to endoscopic resection in our center included assessment of the macroscopic type (according to the Japanese classification) and documentation of the radial location of the neoplastic lesions. Images were recorded which were later assessed by six independent reviewers; intra- and interobserver agreement for the assessment of the macroscopic type were calculated using kappa statistics.
Results: The distribution of the lesions by gross type was as follows: type I, n = 49 (13 %); type IIa, n = 139 (37 %); type IIb, n = 106 (28 %); type IIc, n = 17 (4 %); type IIa + c, n = 62 (16 %); type III, n = 7 (2 %). Type IIb lesions seem to be the most favorable type with regard to differentiation and T category ( P < 0.05). The mean kappa value for the interobserver agreement was 0.86 and the mean kappa value for the intraobserver agreement was 0.89. Most lesions were found at the 12 o'clock and 3 o'clock positions.
Conclusions: Assessment of the macroscopic type may provide important information about the possibility of endoscopic treatment. The harder-to-detect flat lesions are by far the most frequent macroscopic type of neoplastic lesion in Barrett's esophagus.