| [ Summary ] |
In the past, despite initial skepticism on the non-polypoid route of colorectal carcinogenesis in Brazil and other Latin American countries, accumulating evidence points toward the existence of this macroscopic type of neoplasia in South American patients. The incidence of the depressed type colorectal neoplasia in our institution was prospectively evaluated and it revealed 13 cases (0.7%) diagnosed among 1,930 total colonoscopies performed in individuals with abdominal symptoms, family history of colorectal neoplasia and/or positive testing for fecal occult blood. Histological examination of the resected lesions at our institution confirmed previous evidence reported in Japan that regardless of their smaller size, a significantly higher incidence of carcinoma is observed in the depressed type of colorectal neoplasia. A growing number of magnifying scopes and regular utilization of chromoscopy in endoscopy units in Brazil, reflect the medical interest in qualifying the endoscopic diagnosis of colorectal premalignant lesions.
Depressed colorectal neoplasia presenting histologic features comparable to the ones previously reported by Japanese investigators are also detected in Brazilian native patients. In order to prevent colorectal carcinoma in South America, besides colorectal polyps it is necessary to endoscopically diagnose and resect flat and depressed colorectal neoplastic lesions. |