Li Xiao-Hong, Zhang Yu-Tao, Feng Hao
Department of Pathology, The First People's Hospital of Zigong, Zigong 643099, Sichuan Province, China.
Department of Radiology, The First People's Hospital of Zigong, Zigong 643099, Sichuan Province, China.
World J Clin Cases. 2021 Jul 6;9(19):5238-5244. doi: 10.12998/wjcc.v9.i19.5238.
Adenoid cystic carcinoma (ACC) is a common malignant tumor of salivary gland. The lung and liver are frequent sites of distant metastasis. Liver metastasis as the initial clinical manifestation of sublingual gland ACC is very rare.
A 51-year-old Chinese woman presented with a painless mass in the right lobe of liver. The tumor was composed of ductal cells and myoepithelial cells with a morphology including tubiform and cribriform structures. Immunostaining results showed ductal cells positive for CK7, CK14, CK19, CD117, and 34βE12, and negative for MYB, vimentin, ER, PR, and CEA. The myoepithelial cells were positive for p63, calponin and CK5/6. Metastatic salivary ACC was considered, and a sublingual gland mass was revealed by computed tomography. Histological evaluation confirmed primary sublingual gland ACC. Fluorescence hybridization (FISH) did not find an MYB-NFIB fusion gene in specimens from either the primary or metastatic ACC tumors. The sublingual gland ACC relapsed in 20 mo. The recurrent lesion disappeared following local radiation therapy and computed tomography-guided radioactive seed implantation. The patient remains in good condition until now.
Metastatic sublingual gland ACC with initial clinical manifestation as a liver mass is very rare, and was pathologically confirmed in this patient by its histological appearance. Primary hepatic tumors and metastatic carcinomas should be included in the differential diagnosis. Immunohistochemical detection of MYB protein and MYB-NFIB fusion gene detection by FISH can be helpful, but occasional negative results confuse the diagnosis.
腺样囊性癌（ACC）是涎腺常见的恶性肿瘤。肺和肝是常见的远处转移部位。舌下腺ACC以肝转移为初始临床表现非常罕见。
一名51岁中国女性因肝脏右叶无痛性肿块就诊。肿瘤由导管细胞和肌上皮细胞组成，形态学上包括管状和筛状结构。免疫组化结果显示导管细胞CK7、CK14、CK19、CD117和34βE12阳性，MYB、波形蛋白、雌激素受体（ER）、孕激素受体（PR）和癌胚抗原（CEA）阴性。肌上皮细胞p63、钙调蛋白和CK5/6阳性。考虑为涎腺ACC转移，计算机断层扫描显示舌下腺有肿块。组织学评估证实为原发性舌下腺ACC。荧光原位杂交（FISH）在原发性和转移性ACC肿瘤标本中均未发现MYB-NFIB融合基因。舌下腺ACC在20个月后复发。局部放疗及计算机断层扫描引导下放射性粒子植入后，复发病灶消失。患者至今状况良好。
以肝脏肿块为初始临床表现的转移性舌下腺ACC非常罕见，该患者经组织学表现病理确诊。鉴别诊断应包括原发性肝肿瘤和转移性癌。免疫组化检测MYB蛋白及FISH检测MYB-NFIB融合基因可能有帮助，但偶尔的阴性结果会使诊断混淆。
