Division of Digestive Surgery, Department of Surgery, Kyoto Prefectural University of Medicine, Kawaramachihirokoji, Kamigyo-ku, Kyoto, Japan.
J Surg Oncol. 2012 Jun 15;105(8):800-4. doi: 10.1002/jso.23010. Epub 2011 Dec 20.
This study was designed to evaluate the clinical significance of undifferentiated component in differentiated T1/T2 gastric adenocarcinoma.
Two hundred thirty-one patients who underwent curative gastrectomy were diagnosed pathologically as differentiated type T1/T2 gastric cancer according to Japanese Classification of Gastric Carcinoma (JCGC). The patients were divided into subgroups, pure differentiated type (pure D group, 181 patients) and differentiated-predominant mixed type (D > U group, 51 patients). The clinicopathological features of D > U group were compared with those of pure D group, and also those of undifferentiated-predominant type (U > D group).
Patients in D > U group were more likely to have larger and deeper tumors with lymphatic invasion and metastases than pure D group. However, there was no significant difference in clinicopathological factors between D > U and U > D groups, except for depth of tumor invasion. The postoperative 5-year survival rate of D > U group was significantly poorer than that of pure D group (88% and 98%, P = 0.011). Multivariate analysis revealed the presence of undifferentiated component was an independent prognostic factor.
The presence of undifferentiated component in differentiated T1/T2 gastric cancer is associated with tumor progression. Therefore, the decision criterion of histological mixed type in TNM classification is better suited than JCGC in T1/T2 gastric cancer.
本研究旨在评估分化型 T1/T2 胃腺癌中未分化成分的临床意义。
231 例患者接受根治性胃切除术，病理诊断为日本胃癌分类（JCGC）分化型 T1/T2 胃癌。患者分为亚组，纯分化型（纯 D 组，181 例）和分化优势混合型（D＞U 组，51 例）。比较 D＞U 组与纯 D 组、未分化优势型（U＞D 组）的临床病理特征。
D＞U 组患者肿瘤较大、较深，且有淋巴管浸润和转移，较纯 D 组更为常见。然而，两组间除肿瘤浸润深度外，在临床病理因素方面无显著差异。D＞U 组患者术后 5 年生存率明显低于纯 D 组（88%和 98%，P=0.011）。多因素分析显示，未分化成分的存在是独立的预后因素。
在分化型 T1/T2 胃腺癌中存在未分化成分与肿瘤进展相关。因此，与 JCGC 相比，TNM 分类中组织学混合类型的判断标准更适合 T1/T2 胃腺癌。
