Hong Jin Yoon1, Yong Hoon Kim1, Jie-Hyun Kim2, HyunKi Kim3, Hoguen Kim3, Jae Jun Park1, Young Hoon Youn1, Hyojin Park1, Jong Won Kim4, Woo Jin Hyung5, Sung Hoon Noh5, Seung Ho Choi4. 1. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea; Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea. 2. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea; Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea. Electronic address: otilia94@yuhs.ac. 3. Department of Pathology, Yonsei University College of Medicine, Seoul, South Korea. 4. Department of Surgery, Yonsei University College of Medicine, Seoul, South Korea; Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea. 5. Department of Surgery, Yonsei University College of Medicine, Seoul, South Korea.
Abstract
PURPOSE: Early gastric cancer (EGC) of mixed histology is more aggressive than other histologies. In addition, signet ring cell (SRC) mixed histology shows more submucosal invasion and greater lymph node metastasis (LNM). However, there are no criteria for endoscopic resection (ER) in mixed histology. Therefore, this study investigated whether new criteria for mixed histology are necessary for ER in EGC. METHODS: From January 2005 to December 2012, 3419 patients with EGC underwent surgery. Lesions were classified using three histological classifications: the Japanese classification; World Health Organization (WHO) classification including SRC mixed histology; and Lauren classification. The mixed type in the Lauren classification was also reclassified according to the proportion of differentiated and undifferentiated components. Clinicopathological characteristics were compared according to histological classifications, with special reference to the ER criteria. RESULTS: With the Lauren classification, 179 (5.3%) lesions were classified as mixed type, including 54 (30.2%) lesions as the differentiated-predominant mixed type. There were 361 (10.6%) lesions classified as SRC mixed histology. Mixed-type lesions in the Lauren classification and SRC mixed lesions were significantly associated with larger size and a greater LNM. Among the lesions meeting the ER criteria, 20 (1.6%) and 55 (4.7%) were categorized as mixed type by the Lauren classification and SRC mixed histology, respectively. However, there was no LNM among the lesions recategorized into mixed histology. CONCLUSIONS: Mixed histology showed no LNM among the lesions met the present ER criteria. Thus, separate criteria for mixed histology might be not necessary in the criteria for ER in EGC.
PURPOSE: Early gastric cancer (EGC) of mixed histology is more aggressive than other histologies. In addition, signet ring cell (SRC) mixed histology shows more submucosal invasion and greater lymph node metastasis (LNM). However, there are no criteria for endoscopic resection (ER) in mixed histology. Therefore, this study investigated whether new criteria for mixed histology are necessary for ER in EGC. METHODS: From January 2005 to December 2012, 3419 patients with EGC underwent surgery. Lesions were classified using three histological classifications: the Japanese classification; World Health Organization (WHO) classification including SRC mixed histology; and Lauren classification. The mixed type in the Lauren classification was also reclassified according to the proportion of differentiated and undifferentiated components. Clinicopathological characteristics were compared according to histological classifications, with special reference to the ER criteria. RESULTS: With the Lauren classification, 179 (5.3%) lesions were classified as mixed type, including 54 (30.2%) lesions as the differentiated-predominant mixed type. There were 361 (10.6%) lesions classified as SRC mixed histology. Mixed-type lesions in the Lauren classification and SRC mixed lesions were significantly associated with larger size and a greater LNM. Among the lesions meeting the ER criteria, 20 (1.6%) and 55 (4.7%) were categorized as mixed type by the Lauren classification and SRC mixed histology, respectively. However, there was no LNM among the lesions recategorized into mixed histology. CONCLUSIONS: Mixed histology showed no LNM among the lesions met the present ER criteria. Thus, separate criteria for mixed histology might be not necessary in the criteria for ER in EGC.