Shinozaki-Ushiku Aya, Ishikawa Shumpei, Komura Daisuke, Seto Yasuyuki, Aburatani Hiroyuki, Ushiku Tetsuo
Department of Pathology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Department of Preventive Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Gastric Cancer. 2020 Sep;23(5):944-947. doi: 10.1007/s10120-020-01061-9. Epub 2020 Mar 18.
NTRK gene rearrangements occur in a wide spectrum of tumors and are actionable events predictive of response to TRK inhibitor. We report the first case of gastric carcinoma harboring a NTRK fusion in a 79-year-old man. The tumor was composed predominantly of poorly cohesive carcinoma with focal tubular differentiation. Solid sheet-like or nested pattern of large oxyphilic cells was also noted in 10% of tumor. Pan-Trk immunohistochemistry demonstrated Trk expression with a diffuse cytoplasmic and dot-like staining only in the solid component. Extensive lymphatic invasion and multiple nodal metastases were noted and were predominated by Trk-positive component. A novel ATP1B1-NTRK1 fusion was detected by RNA-seq using fresh frozen sample. The patient died of the disease, despite surgery and chemotherapy. Although extremely rare, NTRK rearrangement does occur in gastric carcinoma and might be associated with aggressive phenotype as well as histologic features like solid growth with extensive lymphatic invasion.
NTRK基因重排在多种肿瘤中发生，是可预测对TRK抑制剂反应的可靶向事件。我们报告了首例79岁男性胃腺癌伴有NTRK融合的病例。肿瘤主要由低黏附性癌组成，伴有局灶性管状分化。在10%的肿瘤中还可见大片嗜酸性大细胞呈实性片状或巢状排列。泛Trk免疫组化显示Trk表达，仅在实性成分中呈弥漫性胞质和点状染色。可见广泛的淋巴浸润和多处淋巴结转移，且以Trk阳性成分为主。使用新鲜冷冻样本通过RNA测序检测到一种新的ATP1B1-NTRK1融合。尽管接受了手术和化疗，患者仍死于该疾病。虽然极为罕见，但NTRK重排确实在胃癌中发生，可能与侵袭性表型以及实性生长伴广泛淋巴浸润等组织学特征有关。
