探讨原发性胃淋巴上皮瘤样癌(LELC)的临床病理特点、CT影像特征，以提高对该病的认识。

回顾性分析2016年2月至2021年6月郑州大学第一附属医院收治20例经手术病理证实的胃LELC患者的临床、病理及CT影像资料。男性16例、女性4例；年龄31~76岁，中位年龄58岁。全部患者均接受CT平扫及增强检查，由2名经验丰富的腹部放射科医师对影像资料进行观察分析，包括病灶的部位、形态、生长方式、长径与厚径的比值、密度、黏膜表面有无溃疡，病灶增强方式及强化程度等。所有标本均行HE染色及免疫组织化学染色诊断。

胃LELC位于胃体9例，贲门-胃底8例，胃窦3例，病灶长径为1.5~8.3 cm，平均(4.1±1.9)cm，病灶厚径为1.0~7.0 cm，平均(3.2±1.6)cm，厚度与长径的比值为0.33~1.00(0.79±0.17)；9例表现为胃壁局限性肿块，4例表现为胃壁向心性增厚，4例表现为黏膜下肿块，3例表现为胃壁弥漫性肿块；13例病灶表面出现溃疡，仅1例病灶内见坏死；平扫CT值为31~57(42.53±7.54)HU，动脉期CT值为59~118(87.00±18.64)HU，静脉期CT值为50~123(91.57±17.72)HU，增强后14例强化均匀，6例强化不均；16例呈持续性强化，4例呈渐进性强化，其中11例强化明显。病理示14例为溃疡型，6例为隆起型。脉管癌栓7例，神经侵犯12例；7例侵犯浆膜下层，5例侵犯肌层，5例侵犯胃壁全层，2例侵犯浆膜层，1例侵犯黏膜下层。20例原位杂交EBER表达均为阳性。

胃LELC好发于中老年男性的近端胃，CT上形态具有多样性，亦可表现为黏膜下肿块，病灶密度均匀且不易出现坏死，增强多呈持续性明显强化，诊断依靠组织病理学及免疫组化，确诊时临床分期较早，淋巴结受累少见，预后较好。

To explore the clinicopathological features and CT imaging features of primary gastric lymphoepithelioma-like carcinoma(LELC)in order to improve the understanding of the disease.

The clinical, pathological and CT imaging data of 20 patients with gastric LELC confirmed by surgery and pathology admitted to the First Affiliated Hospital of Zhengzhou University from February 2016 to June 2021 were retrospectively analyzed.There were 16 males and 4 females.They ranged in age from 31 to 76 years, with a median age of 58 years.All patients underwent CT plain and enhanced examinations, and two experienced abdominal radiologists observed and analyzed the imaging data, including lesion location, morphology, growth pattern, ratio of length-diameter to thick-diameter, density, presence of ulcers on the mucosal surface, and enhancement pattern and degree of lesions.All specimens were diagnosed by HE staining and immunohistochemical staining.

Gastric LELC was located in the gastric body in 9 cases, cardia-fundus in 8 cases, and gastric sinus in 3 cases.The length-diameter of the lesions ranged from 1.5 to 8.3 cm, with a mean of(4.1±1.9)cm, the thick-diameter of the lesions ranged from 1.0 to 7.0 cm, with a mean of(3.2±1.6)cm, and the ratio of thickness to length-diameter ranged from 0.33 to 1.00(0.79±0.17). Nine cases showed a limited mass in the gastric wall, 4 cases showed centripetal thickening of the gastric wall, 4 cases showed a submucosal mass, and 3 cases showed a diffuse mass in the gastric wall; 13 cases showed ulceration on the surface of the lesion, and only 1 case showed necrosis within the lesion.CT values ranged from 31 to 57(42.53±7.54)HU on plain CT, 59 to 118(87.00±18.64)HU on arterial CT, and 50 to 123(91.57±17.72)HU on venous CT.After enhancement, 14 cases had uniform enhancement and 6 cases had uneven enhancement; 16 cases showed persistent enhancement and 4 cases showed progressive enhancement, of which 11 cases had significant enhancement.Pathology showed that 14 cases were ulcer type and 6 cases were protuberant type.There were 7 cases of vascular tumor thrombus and 12 cases of nerve invasion; 7 cases invaded the subserous layer, 5 cases invaded the muscular layer, 5 cases invaded the full layer of gastric wall, 2 cases invaded the serous layer and 1 case invaded the submucosa.Twenty cases were positive for EBER expression by in situ hybridization.

Gastric LELC usually occurs in the proximal stomach of middle-aged and elderly men.The morphology on CT is diverse, and it can also be shown as a submucosal mass.The density of the focus is uniform, and necrosis is not easy to occur.Most of the enhancement shows significantly persistent enhancement.The diagnosis depends on histopathology and immunohistochemistry.The clinical stage is early when the diagnosis is made, lymph node involvement is rare, and the prognosis is good.