结外NK/T细胞淋巴瘤诊治进展

Research progress of extranodal NK-T cell lymphoma

结外NK/T细胞淋巴瘤(ENKTCL)多见于亚洲和中南美洲,病因可能与EB病毒感染有关,病理学表现为多形态肿瘤组织侵犯血管。肿瘤细胞特异性表达CD2、CD56和胞浆CD3,但TCR基因重排阴性。确诊需病理组织学检查,影像学检查可对诊断提供帮助。化疗主要用于疾病播散、复发和放疗失败者。在传统的CHOP方案基础上加用足叶以甙、亚硝基脲类、左旋门冬酰胺酶等可能提高疗效,并可作为复发患者的挽救治疗。预后因素的研究显示分期、B组症状、LDH水平、初治疗效、血清nm23-H1水平与结外NK/T细胞淋巴瘤的预后有关。

Extranodal natural killer （NK）/T cell lymphoma is recognized as a distinct entity of malignant lymphoma. These lymphomas are prevalent in East Asia and certain parts of Central and South America. The onset of these lymphomas has a strong association with Epstein-Barr virus. The pathological features are angiocentricity and angioinvasion accompanied by angiodestruction and zonal necrosis. The tumour affects mainly the nose and midface although the disease can also arise on the skin, gastrointestinal tract, testes, CNS, and so on. Immunophenotypically, NK lymphoma cells are characterized by the expression of CD2, cytoplasmic CD3 and CD56. But TCR gene rearrangement is usually negative. Recently, Protocadherin 15（PCDHI5） was specially detected in NK cell tumors. Radiotherapy is usually used in stages Ⅰ and Ⅱdisease. The planning target fields should include all macroscopic lesions and enough margins. Chemotherapy is recommended to use in patients with dissemination stage of the disease, recurrence and failure to radiotherapy. CHOP based regimen combined with some agents （ e. g. etoposide, nitrosourea, L-asparaginase） may provide better treatment Results than conventional CHOP regimen and can be used in patients with recurrence. SCT may be considered as a first-line option for patients with stage Ⅲ/Ⅳ extranodal NK/T-cell lymphoma. Disease stage, B-group symptom, serum LDH level, serum nm23-H1 and initial treatment response are found to be independent prognostic factors for extranodal NK/T cell lymphoma.