Mangogna Alessandro, Cox Maria Christina, Ruco Luigi, Lopez Gianluca, Belmonte Beatrice, Di Napoli Arianna
Pathology Unit, Clinical Department of Medical, Surgical and Health Science, University of Trieste, Cattinara Hospital, 34149 Trieste, Italy.
Haematology Unit, Sant'Andrea Hospital, Sapienza University, 00189 Rome, Italy.
Diagnostics (Basel). 2020 May 26;10(6):341. doi: 10.3390/diagnostics10060341.
Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is the most common entity of mature T-cell neoplasms. PTCL-NOS generally has an aggressive behavior and is often refractory to standard therapy. Only a few cases of PTCL with aberrant expression of B-cell antigens have been reported so far. This phenotypic aberrancy may lead to misdiagnosis as B-cell non-Hodgkin lymphomas and eventual inappropriate patient management, whereas in an accurately diagnosed PTCL, the presence of CD20 may appear as an appealing therapeutic target. In this setting, response to anti-CD20 monoclonal antibody in combination with chemotherapy has been poorly explored. We describe the case of a 59-year-old male diagnosed by a pathological and molecular approach as PTCL-NOS with aberrant co-expression of the B-cell antigens CD20 and CD79a, which proved non-responsive to the addition of rituximab to standard polychemotherapy. This case highlights that the presence of CD20 in PTCL may be misleading in the diagnosis and also act as a lure for the clinician to adopt a rituximab-based treatment, the effectiveness of which is undefined as the molecular mechanisms underlying B-cell marker expression in PTCL.
外周T细胞淋巴瘤，非特指型（PTCL-NOS）是成熟T细胞肿瘤中最常见的类型。PTCL-NOS通常具有侵袭性，对标准治疗往往耐药。迄今为止，仅有少数PTCL病例报告存在B细胞抗原异常表达。这种表型异常可能导致误诊为B细胞非霍奇金淋巴瘤，并最终导致患者管理不当，而在准确诊断的PTCL中，CD20的存在可能成为一个有吸引力的治疗靶点。在这种情况下，抗CD20单克隆抗体联合化疗的疗效尚未得到充分研究。我们描述了一例59岁男性病例，通过病理和分子方法诊断为PTCL-NOS，伴有B细胞抗原CD20和CD79a的异常共表达，该病例在标准多药化疗中加用利妥昔单抗后无效。该病例强调，PTCL中CD20的存在在诊断中可能产生误导，也可能诱使临床医生采用基于利妥昔单抗的治疗方法，但其有效性尚不确定，因为PTCL中B细胞标志物表达的分子机制尚不明确。
