Carcinoma, Signet Ring CellAdenocarcinoma, MucinousStomach NeoplasmsAppendiceal NeoplasmsUmbilicusAlcian BlueMicrosatellite InstabilityRare DiseasesGastrectomyMucinsAdenocarcinomaImmunohistochemistryProto-Oncogene Proteins B-rafPeritoneal NeoplasmsColorectal NeoplasmsCadherinsGallbladder NeoplasmsPyloric AntrumEndoscopy, GastrointestinalAppendectomyras ProteinsNeoplasm StagingChromosomes, Human, Pair 18Loss of HeterozygosityRectal NeoplasmsGastric MucosaHistocytochemistryMicrosatellite RepeatsFatty Acid SynthasesColonic NeoplasmsO(6)-Methylguanine-DNA MethyltransferaseNeoplasms