title: Intravascular NK-cell lymphoma: a case report and review of the literature.
abstract: BACKGROUND
  Intravascular NK-cell lymphoma (IVNKL) is an extremely rare variant of non-Hodgkin lymphoma. To our knowledge, there are only a few cases reported in the English literature. Here, a case of a 29-year-old male with IVNKL involving the skin of the trunk and 4 extremities and liver is presented. A comprehensive literature review is undertaken to summarize the clinical and pathological features of this disorder.
  
  
  RESULTS
  In our case, large neoplastic lymphoid cells are restricted to the lumen of small vessels and exhibit the phenotype of a true NK cell. The morphology and immunophenotype, positivity of EBER and NK-cell origin are similar to other IVNKL cases. In addition, some cases including ours carry a poor prognosis as multiple systems or vital organs are involved.
  
  
  CONCLUSIONS
  In summary, we report a case of an unusual intravascular lymphoma of NK-cell lineage that displays both clinical and pathological features and compare it with other differential diagnoses. It is important to recognize this rare entity to make an appropriate diagnosis and achieve a better understanding regarding the treatment and prognosis.
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. Biyeye81@126.com.
authors.forename: Yalan
authors.initials: Y
authors.lastname: Bi
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. Huozhen1976@126.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Huo
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. LiangZY@pumch.cn.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Liang
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. MengYX@pumch.cn.
authors.forename: Yunxiao
authors.initials: Y
authors.lastname: Meng
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. David_jia0814@163.com.
authors.forename: Congwei
authors.initials: C
authors.lastname: Jia
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. Shixiaohua3762@hotmail.com.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Shi
authors.affiliation: Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. sallysonglan@sina.com.
authors.forename: Lan
authors.initials: L
authors.lastname: Song
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. LuoYF@pumch.cn.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. LingQ@pumch.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Ling
authors.affiliation: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No.1 Shuaifuyuan, Wangfujing, DongCheng District, Beijing, 100730, China. Liuth_pumch192911@yahoo.com.
authors.forename: Tonghua
authors.initials: T
authors.lastname: Liu
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D001706:Biopsy; D019070:Cell Lineage; D003937:Diagnosis, Differential; D017809:Fatal Outcome; D019672:Genes, T-Cell Receptor; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D054391:Lymphoma, Extranodal NK-T-Cell / Q000188:drug therapy / Q000235:genetics / Q000276:immunology / Q000473:pathology* / Q000821:virology; D008297:Male; D055611:Natural Killer T-Cells / Q000276:immunology / Q000473:pathology* / Q000821:virology; D010641:Phenotype; D011237:Predictive Value of Tests; D012367:RNA, Viral / Q000235:genetics; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D019043:Vascular Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000276:immunology / Q000473:pathology* / Q000821:virology
chemical_list: D014408:Biomarkers, Tumor; D012367:RNA, Viral