Masato Taniguchi

Invasion depth diagnosis of depressed type early colorectal cancers by combined use of videoendoscopy and chromoendoscopy

BACKGROUND Depressed type early colorectal cancers are found less frequently than other polypoid cancers although they have a higher submucosal invasion rate. Recently videocolonoscopy and chromoendoscopy have become available and precise descriptions of these lesions are now routine. Because endoscopic mucosal resection is designated for intramucosal and focally extended submucosal (m-sm1) cancers, an evaluation of the characteristic findings indicating invasion depth with these modalities is important. METHODS Between January 1991 and March 1996, 64 depressed type early colorectal cancers were detected and treated. When a faint abnormality of the mucosa was suspected by routine videocolonoscopy, 0.1% of indigo carmine solution was sprayed on the mucosal surface (chromoendoscopy). Colonoscopic findings of m-sm1 cancers and moderately and massively extended submucosal (sm2-3) cancers were retrospectively reviewed and compared with confirmed histologic findings. RESULTS Characteristic colonoscopic findings needed for surgical operation were as follows: (1) expansion appearance, (2) deep depression surface, (3) irregular bottom of depression surface, and (4) folds converging toward the tumor. By using these findings, the invasion depth of depressed type early colorectal cancers could be correctly determined in 58 of 64 lesions (91%). CONCLUSIONS Characteristic colonoscopic findings obtained by a combination of videocolonoscopy and chromoendoscopy are useful for determination of the invasion depth of depressed type colorectal cancers, an essential factor in choosing a treatment modality.

Genetic and Phenotypic Polymorphisms of the A Subunit of Coagulation Factor XIII in Japanese Population

To clarify whether genetic polymorphisms in exon 14 of Coagulation factor XIII A-subunit gene (FXIIIA) affect phenotype expressions, we studied genetic polymorphisms in exon 14 of FXIIIA in a Japanese population and the relationship between the genetic polymorphisms and phenotype expression. Genetic polymorphisms in exon 14 of FXIIIA of 144 unrelated Japanese were analyzed by single-strand conformation polymorphism. Plasma FXIIIA antigen concentrations, FXIII activities, and phenotype were also determined by two-dimensional electrophoresis. The frequencies of the three genotypes, the homozygote (AD), the homozygote (BC) and the heterozygote (AD/BC), were 77.1, 0.7, and 22.2%, respectively. The gene frequencies of AD and BC were 0.88 and 0.12. We detected AD (GTTand BC (ATTat codon 650 and 651 of exon 14. There were no significant differences of FXIIIA antigen concentrations and FXIII activities between these genotypes. We detected three pl differences among them as being pls of 5.3, 5.6, 5.8 in the homozygote (AD) and the heterozygote (AD/BC), and a pl of 5.8 in the homozygote (BC). These polymorphisms affected isoelectric mobility, but did not affect protein levels, enzyme activities, or the molecular weight of FXIII.