Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
Department of Pathology, Aga Khan University Hospital, Nairobi, Kenya.
Am J Clin Pathol. 2021 Jun 17;156(1):42-55. doi: 10.1093/ajcp/aqaa201.
Peripheral T-cell lymphomas (PTCLs) are heterogeneous, clinically aggressive, and rare. Subtype distribution varies by geographic location; however, data from sub-Saharan Africa (SSA) are lacking. We sought to elucidate clinicopathologic features of PTCL in SSA.
We reviewed PTCL consultation cases from three SSA countries. PTCL subtype was determined per 2017 World Health Organization classification. Cases with sufficient material were evaluated by polymerase chain reaction for human T-cell leukemia virus type 1 (HTLV-1) and T-cell receptor γ (TCRG) rearrangement.
Among 32 cases, median age was 45 years and male-to-female ratio was 1.7. Thirty (94%) of 32 cases required additional workup for subclassification. PTCL, not otherwise specified (PTCL-NOS) was the most common subtype (13/32, 41%), followed by PTCL with T-follicular helper phenotype (6/32, 19%) and systemic anaplastic large cell lymphoma (6/32, 19%). Four (16%) of 25 cases were Epstein-Barr virus positive (EBV+) (2/2 extranodal natural killer/T-cell lymphoma, 1/13 PTCL-NOS, and 1/4 angioimmunoblastic T-cell lymphoma with EBV+ immunoblasts). Two (15%) of 13 patients with PTCL-NOS were human immunodeficiency virus positive. No cases with evaluable DNA (0/15) were HTLV-1 positive, and 9 of 10 showed clonal TCRG rearrangements.
In comparison to Western studies, PTCLs from SSA show similar subtype distribution and male predominance but a younger age at diagnosis. Appropriate diagnosis of PTCL requires extensive ancillary testing not readily available in low-income countries, including much of SSA.
外周 T 细胞淋巴瘤（PTCLs）具有异质性、侵袭性强、发病率低等特点。亚型分布因地理位置而异，但撒哈拉以南非洲（SSA）的数据尚缺乏。本研究旨在阐明 SSA 地区 PTCL 的临床病理特征。
我们回顾了来自三个 SSA 国家的 PTCL 会诊病例。根据 2017 年世界卫生组织分类确定 PTCL 亚型。对有足够材料的病例进行人 T 细胞白血病病毒 1（HTLV-1）和 T 细胞受体 γ（TCRG）重排的聚合酶链反应评估。
32 例患者的中位年龄为 45 岁，男女比例为 1.7。为了进一步分类，32 例中的 30 例（94%）需要进行额外的检查。未特指的外周 T 细胞淋巴瘤（PTCL-NOS）是最常见的亚型（13/32，41%），其次是滤泡辅助 T 细胞表型的 PTCL（6/32，19%）和系统性间变性大细胞淋巴瘤（6/32，19%）。25 例中有 4 例（16%）为 EBV 阳性（2/2 结外自然杀伤/T 细胞淋巴瘤，1/13 PTCL-NOS，和 1/4 血管免疫母细胞性 T 细胞淋巴瘤伴 EBV+免疫母细胞）。13 例 PTCL-NOS 患者中有 2 例（15%）HIV 阳性。15 例可评估 DNA 患者中无一例 HTLV-1 阳性，10 例中有 9 例 TCRG 重排呈克隆性。
与西方研究相比，来自 SSA 的 PTCL 具有相似的亚型分布和男性为主的发病趋势，但诊断时年龄更轻。PTCL 的正确诊断需要广泛的辅助检测，而这些检测在低收入国家，包括大部分 SSA 国家，并不容易获得。
