BACKGROUND AND AIMS: This study was designed to evaluate the discrepancies in the histological grade of submucosal (SM) gastric carcinoma between biopsy and resected specimens graded using the Japanese classification of gastric carcinoma (JCGC) and TNM classifications. SAMPLES AND METHODS: This study comprised 250 consecutive paired biopsy and curative gastrectomy resection specimens from SM gastric carcinomas obtained between 1995 and 2011. RESULTS: Of the 250 SM gastric carcinomas, 47 (19%) were smaller than 1.5 cm. Of 32 biopsy specimens diagnosed as differentiated type according to the JCGC classification, only 1 (3.1%) was eventually diagnosed as undifferentiated type according to the resected specimen. In contrast, of 25 biopsy specimens diagnosed as differentiated type according to the TNM classification, 2 (8.0%) were eventually diagnosed as undifferentiated type according to the resected specimens. These specimens were all mixed-type carcinomas. CONCLUSIONS: Mixed-type gastric carcinoma is associated with a high incidence of histological discrepancy between biopsy and resected specimens in both JCGC and TNM classification. For mixed-type gastric carcinoma in particular, the treatment strategy selected from the limited treatments options available should be based on the histological grade according to biopsy specimens.
BACKGROUND AND AIMS: This study was designed to evaluate the discrepancies in the histological grade of submucosal (SM) gastric carcinoma between biopsy and resected specimens graded using the Japanese classification of gastric carcinoma (JCGC) and TNM classifications. SAMPLES AND METHODS: This study comprised 250 consecutive paired biopsy and curative gastrectomy resection specimens from SM gastric carcinomas obtained between 1995 and 2011. RESULTS: Of the 250 SM gastric carcinomas, 47 (19%) were smaller than 1.5 cm. Of 32 biopsy specimens diagnosed as differentiated type according to the JCGC classification, only 1 (3.1%) was eventually diagnosed as undifferentiated type according to the resected specimen. In contrast, of 25 biopsy specimens diagnosed as differentiated type according to the TNM classification, 2 (8.0%) were eventually diagnosed as undifferentiated type according to the resected specimens. These specimens were all mixed-type carcinomas. CONCLUSIONS: Mixed-type gastric carcinoma is associated with a high incidence of histological discrepancy between biopsy and resected specimens in both JCGC and TNM classification. For mixed-type gastric carcinoma in particular, the treatment strategy selected from the limited treatments options available should be based on the histological grade according to biopsy specimens.