Mature T-cell and NK-cell lymphomas: updates on molecular genetic features

Mature T-cell and NK-cell lymphomas are a heterogeneous group of rare and typically aggressive neoplasms. Diagnosis and subclassification have historically relied primarily on the integration of clinical, histologic, and immunophenotypic features, which often overlap. The widespread application of a variety of genomic techniques in recent years has provided extensive insight into the pathobiology of these diseases, allowing for more precise diagnostic classification, improved prognostication, and development of novel therapies. In this review, we summarize the genomic features of the most common types of mature T-cell and NK-cell lymphomas with a particular focus on the contribution of genomics to biologic insight, classification, risk stratification, and select therapies in the context of the recently published International Consensus and updated World Health Organization classification systems.

[Two Lethal Cases of Monomorphic Epitheliotropic Intestinal T-cell Lymphoma Deteriorated Rapidly After Emergency Surgery for Intestinal Perforation]

Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare and aggressive form of primary gastrointestinal T-cell lymphoma. Symptoms can vary but often include fever, abdominal pain, weight loss, diarrhea, obstruction, and perforation. Disease-specific symptoms rarely present before patients reach an advanced stage, which contributes to delayed diagnosis and poor survival outcomes. Approximately half of the patients with MEITL undergo emergency surgery for acute intestinal obstruction or perforation, leading to peritonitis, septic shock, and multiple organ failure. These factors contribute to treatment delays, which are associated with a worse prognosis, particularly in the case of chemotherapy. This paper reports two fatal cases of patients with MEITL who deteriorated rapidly after emergency surgery for intestinal perforation. Patient 1 complained of persistent diarrhea, but a delayed diagnosis led to bowel perforation, and the subsequent chemotherapy treatment was canceled. Patient 2 was diagnosed relatively early, but treatment was delayed due to intestinal perforation. Despite its rarity, MEITL should be considered through a "high index of suspicion" approach when a patient complains of unexplained abdominal pain and diarrhea. This is expected to improve early diagnosis and ultimately patient prognosis.

[Peripheral T-cell lymphoma with follicular helper of T cell phenotype of Waldeyer's ring: a clinicopathological and genetic study of eight cases]

Objective: To study the clinicopathologic and genetic features of Waldeyer's ring peripheral T-cell lymphoma with follicular helper T cell immunophenotypes (wPTCL-TFH), with comparison to the nodal peripheral T-cell lymphoma with TFH immunophenotypes (nPTCL-TFH) and angioimmunoblastic T-cell lymphoma (AITL), as to know this rare tumor better. Methods: The clinical data, histopathology features, EBV positivity, T cell clonality and IDH2(R172) gene mutation in 8 cases of wPTCL-TFH were collected at the First Affiliated Hospital of Zhengzhou University from December 2015 to April 2019, and analyzed by immunohistochemistry, in situ hybridization, TCR gene rearrangement (BIOMED-2) and Sanger sequencing.Follow-up data were obtained by telephone. Results: There were 6 males and 2 females with a median age of 62.5 years (age ranging from 30 to 75 years). All patients had neither fever nor skin manifestations, but were all found mucosa thickened or mass of waldeyer's ring with multiple lymph nodes enlarged by PET-CT/CT scans. Five of the 7 patients were at advanced stages (Ⅲ/Ⅳ stage). Microscopically, the mucosa was infiltrated diffusely and characteristically by numerous small-medium sized lymphocytes, lacking polymorphous inflammatory background and extra-follicular expansion of follicular dendritic cell networks (FDC networks). The clear T cells presented in 5 cases. Ulcers on mucosal surfaces (6 cases) and local-extensive loss of intramucosal glands (7 cases) were commonly noted. Granulomas composed of epithelioid histiocytes were observed in 2 cases. Immunohistochemically, all the tumor cells expressed CD4 and at least 2 types of follicular helper of T cell (TFH) markers: PD-1 (8/8), bcl-6 (8/8), CXCL13 (7/8) and CD10 (1/8). Most of the cases (6 cases) expressed CD30. EBV positive appeared in 4 cases. All 8 cases were T cell monoclonal. IDH2(R172) were wild-type in 6 cases. One patient died at the follow-up time on 18 months; the other 7 survived (the follow-up time varied from 3 to 10 months). Conclusions: wPTCL-TFH is rare, and its clinicopathological features are similar to nPTCL-TFH which may be the manifestation of the same disease at different stage, and partly overlapped with AITL. The differential diagnosis from PTCL-NOS is necessary and comprehensive analyses of clinical, morphological, immunohistochemical and genetic features can help make a correct diagnosis.

[Clinical outcomes of peripheral blood stem cell transplantation for aggressive peripheral T-cell lymphoma]

目的

研究外周血造血干细胞移植治疗外周T细胞淋巴瘤（PTCL）的疗效。

方法

回顾性分析解放军总医院血液科2007年6月至2017年6月接受外周血造血干细胞移植PTCL患者的临床资料。

结果

共有41例PTCL患者纳入研究，男30例，女11例，中位年龄38（13~57）岁。17例行自体外周血造血干细胞移植（auto-PBSCT），24例行异基因外周血造血干细胞移植（allo-PBSCT）。auto-PBSCT组ALK阳性间变大细胞淋巴瘤占47.1%（8/17），allo-PBSCT组NK/T细胞淋巴瘤和外周T细胞淋巴瘤-非特指型占66.7%（16/24）。auto-PBSCT组患者移植前疾病处于完全缓解（CR）状态者占58.8%（10/17），疾病进展（PD）状态者占11.8%（2/17）；allo-PBSCT组移植前疾病状态为CR者8.3%（2/24），PD者45.8%（11/24）。auto-PBSCT组和allo-PBSCT组移植后2年总生存率、无病生存率差异均无统计学意义[（64.0±10.8）%对（53.5±9.7）%，P=0.543；（57.1±12.4）%对（53.5±10.6）%，P=0.701]。auto-PBSCT组6例死亡，5例死于复发；allo-PBSCT组12例死亡，其中5例死于复发，7例为移植相关死亡。

结论

auto-PBSCT和allo-PBSCT均是PTCL的有效治疗方法。

[Prognostic significance of NCCN-International Prognostic Index (NCCN-IPI) for patients with peripheral T-cell lymphoma treated with CHOP-based chemotherapy]

目的

明确美国国家综合癌症网络国际预后指数（NCCN-IPI）对外周T细胞淋巴瘤（PTCL）患者化疗后的预后评估价值。

方法

回顾性分析2003年1月至2013年5月接受CHOP或CHOP样方案化疗的162例初治PTCL患者的临床资料，采用国际预后指数（IPI）和NCCN-IPI进行危险分层和预后评估。

结果

①162例患者预期5年总生存（OS）和无进展生存（PFS）率分别为33%和20%，中位OS和PFS时间分别为17.0和9.2个月。②多因素分析提示美国东部肿瘤协作组体能状态评分（ECOG评分）≥2分（PFS：HR＝2.418，95%CI 1.535～3.809，P<0.001；OS：HR＝2.347，95%CI 1.435～3.839，P＝0.001）和存在特定的结外病变部位（PFS：HR＝1.800，95%CI 1.216～2.665，P＝0.003；OS：HR＝1.608，95%CI 1.054～2.454，P＝0.027）是影响患者PFS和OS的独立危险因素；ALK⁺是影响间变性大细胞淋巴瘤患者PFS（HR＝0.424，95%CI 0.184～0.975，P＝0.043）及OS（HR＝0.276，95%CI 0.087～0.877，P＝0.029）的独立预后良好因素。③NCCN-IPI低危组患者的生存率显著高于IPI低危组患者（5年OS率74%对54%，χ²＝5.041，P＝0.025；5年PFS率50%对38%，χ²＝5.295，P＝0.021），差异均有统计学意义。

结论

NCCN-IPI较IPI对低危PTCL患者具有更好的预后判断意义，可作为PTCL患者有效的预后分层工具。

[Prognostic value of lymphocyte-to-monocyte ratio in angioimmunoblastic T cell lymphoma]

目的

探究淋巴细胞/单核细胞比值（LMR）在血管免疫母细胞性T细胞淋巴瘤（AITL）患者中的预后价值。

方法

回顾性分析2009年6月至2017年7月南京医科大学第一附属医院收治的64例初诊AITL患者资料。采用ROC曲线计算LMR临界值，并以此将患者分为高LMR和低LMR组，采用Pearson卡方检验及Fisher精确概率法进行组间比较。采用Kaplan-Meier法和Cox回归分析影响无进展生存（PFS）和总生存（OS）的预后因素。

结果

64例患者中，男39例，女25例，中位年龄63（29~89）岁。LMR临界值为3.07。中位随访33（5~103）个月，低LMR与高LMR组比较，患者的PFS时间（9对13个月，P=0.044）和OS时间（16个月对未达到，P=0.014）差异均有统计学意义。多因素分析显示低LMR是影响患者PFS（HR=0.48, 95% CI 0.26~0.92，P=0.027）和OS（HR=0.38，95% CI 0.18~0.82，P=0.013）的独立预后不良因素。亚组分析结果显示，在中高危至高危[非特指型预后指数（PIT）评分2~4分]患者中，低LMR者有更短的PFS和OS时间（P值分别为0.013、0.031），而在低危至中低危（PIT评分0~1分）患者中其差异均无统计学意义（P值分别为0.949、0.238）。

结论

可根据PIT评分及LMR的状态初步评估患者的疾病风险。低LMR提示患者具有更差的预后。

[Classification of malignant lymphomas. Current situation]

BACKGROUND

The World Health Organization (WHO) is planning an update of the WHO classification of malignant lymphomas.

OBJECTIVE

To present new findings concerning the diagnostics and subclassification of malignant lymphomas.

MATERIAL AND METHODS

A selective literature search ( http://www.ncbi.nlm.nih.gov ) was carried out and combined with the practical experiences of the authors in clinicopathological diagnostics.

RESULTS

In recent years an increasing number of early lesions of malignant lymphomas have been described but the potential malignancy of these lesions is at least for some entities still uncertain. Newly defined entities have been described within the group of T-cell lymphomas and prognostic subgroups have been identified in the heterogeneous group of diffuse large B-cell lymphomas. Detection of mutations facilitates the differential diagnostics of morphologically similar diseases and can be an important component of the diagnostics.

CONCLUSION

Recent scientific insights are being included more and more into the diagnostics of lymphomas. The update of the WHO classification is a consequence of these developments.