A national survey of endoscopic mucosal resection for superficial gastrointestinal neoplasia.

BACKGROUND AND STUDY AIM: Studies on endoscopic mucosal resection (EMR) are mostly based on data from centers with high expertise. We report the average EMR results in a national survey of consecutive patients in France. METHODS: A 1-year survey was carried out to record immediate outcome data of all EMRs performed, regardless of lesion size or gastrointestinal location. RESULTS: Overall, 1335 EMRs in 1210 patients were reported by 241 of the 736 gastroenterologists who performed such procedures (33 %). Resections were done for upper gastrointestinal lesions in 125 cases (41 esophageal, 43 gastric, and 41 duodenal lesions), in 45 % of cases using specific EMR techniques such as ligation, cap, or traction. The technique for resecting the 1210 lower gastrointestinal lesions mostly consisted of saline-assisted polypectomy or EMR, with specific techniques used in only 2.2 %. En bloc resection was less common with esophageal (46 %) or duodenal (54 %) neoplasms than in the lower gastrointestinal tract (73 %); size also had some influence (53 % > 1 cm vs. 92 % ≤ 1 cm). The overall complication rate was 5.2 %; the rate was lower for lesions 1 cm or smaller (0.6 % vs. 4.6 %). Fifty-four early and 17 delayed complications were recorded, in 12 % of upper gastrointestinal and 4.6 % of colonic lesions. Surgery became necessary in 1.6 % for upper and 2.9 % for lower gastrointestinal neoplasms. No association was seen between physician EMR caseload and either en bloc resection rate or complication rate. CONCLUSIONS: EMR in general, especially saline-assisted polypectomy in the colon, appears to be reasonably safe even when performed by nonexperts. EMR for larger or for upper gastrointestinal lesions should probably be limited to high-volume centers.

Identification by genomic typing of non-DR3 HLA class II genes associated with myasthenia gravis.

HLA association with myasthenia gravis (MG) has been studied in a series of 114 patients using class I and class II genotyping after PCR amplification. Positive association was found with DR3, particularly in women (RR = 2.6) and in early MG onset (RR = 3.4). DRB1, DRB3, DQB1, DQA1 and B (B8 and B18) genotyping revealed that the association was predominantly with the B8 DRB1*03 DRB3*0101 DQB1*0201 DQA1*0501 ancestral haplotype. This haplotype frequency was also increased in patients with thymic hyperplasia (RR = 3.5) and was greatly reduced in patients with thymoma (RR = 0.35). Sixteen out of 48 patients carrying this 8.1 ancestral haplotype showed absence of B8 (n = 4) or of DR3 (n = 12). HLA class II genotyping further revealed the existence of two other significant associations. MG was positively associated with the DQB1*0604 allele (RR = 3.4), particularly in patients with thymoma (RR = 5.7). Furthermore, the disease was negatively associated with DR1 in females (RR = 0.32). These data suggest that MG is placed under the control of at least three distinct genes: (1) a class II predisposing gene in the 8.1 ancestral haplotype; (2) a thymoma-associated class II allele on the DQB1*0604 haplotype; and (3) a protective allele DR1.