Background: Primary pulmonary lymphoepithelial carcinoma (PPLEC) is a rare form of lung malignancy, accounting for only 0.7% of all lung cancers. It is currently classified as a distinct subtype within squamous cell carcinomas. This study aims to explore the clinicopathological characteristics of PPLEC and its subtypes, with the objective of enhancing understanding and improving diagnostic accuracy for this disease.
Methods: A retrospective analysis was conducted on the clinical, pathological, imaging, and prognostic data of 14 patients diagnosed with PPLEC at the First Affiliated Hospital of Soochow University between February 2019 and June 2023.
Results: A total of 14 cases of PPLEC were identified, including 5 cases of the Regaud type, with ages ranging from 33 to 73 years, comprising 2 males and 3 females; and 9 cases of the Schmincke type, with ages ranging from 36 to 79 years, including 4 males and 5 females. Computed tomography (CT) scans consistently demonstrated soft tissue masses or nodular shadows. Reagud type mainly showed peripheral masses and Schmincke type mainly showed central masses. Pathological examination revealed tumor cells exhibiting syncytial-like growth, accompanied by lymphocytic infiltration and stromal fibrosis, with the Regaud type showing well-defined borders combined with granulomatous inflammation, while the Schmincke type exhibited indistinct tumor margins. Immunohistochemistry showed that CK, CK5/6, P40 and P63 were positive, and the Ki-67 index of Regaud type was lower than that of Schmincke type; notably, all 8 cases tested for programmed death-ligand 1 (PD-L1) were positive. Epstein-Barr virus-encoded RNA (EBER) in situ hybridization was positive in all instances. Among these cases, 6 underwent surgical treatment, and 8 received comprehensive therapy; by the end of the follow-up period, all 14 patients remained alive.
Conclusions: PPLEC is a rare form of malignant lung tumor associated with Epstein-Barr virus (EBV) infection. The Regaud and Schmincke subtypes display distinct imaging and pathological characteristics. In the early stages of the disease, surgical intervention is the primary treatment method; however, for advanced stages, a multimodal treatment approach is utilized, resulting in a relatively favorable prognosis. Immunotherapy represents a promising and effective treatment modality for patients with middle to advanced stage disease exhibiting high PD-L1 expression levels.
【中文题目：14例原发性肺淋巴上皮癌的临床病理分析】 【中文摘要：背景与目的 原发性肺淋巴上皮癌（primary pulmonary lymphoepithelial carcinoma, PPLEC）是一种罕见的肺部恶性肿瘤，其发病率仅占所有肺恶性肿瘤的0.7%。目前，PPLEC被归类为鳞状细胞癌的特殊亚群。本研究旨在探讨PPLEC的两种亚型在临床病理学上的特征，以提升对该疾病的认识和诊断能力。方法 回顾性分析2019年2月至2023年6月苏州大学附属第一医院经病理学证实为PPLEC的14例患者的临床、病理学、影像学及预后资料，并对相关文献进行复习。结果 PPLEC总计14例，其中Regaud型5例，年龄33-73岁，男性2例，女性3例；Schmincke型9例，年龄36-79岁，男性4例，女性5例。计算机断层扫描（computed tomography, CT）均表现为软组织肿块影或结节影，Reagud型以周围型肿块为主，Schmincke型以中央型为主。病理学示肿瘤细胞呈合胞体样生长，伴随淋巴细胞浸润及间质纤维化，Regaud型边界清晰合并肉芽肿性炎性病变，Schmincke型肿瘤边界模糊。免疫组织化学示肿瘤细胞CK、CK5/6、P40、P63阳性，Regaud型Ki-67增殖指数低于Schmincke型；其中8例接受程序性细胞死亡配体1（programmed death-ligand 1, PD-L1）检测均呈阳性；EB病毒编码的小RNA（Epstein-Barr virus-encoded RNA, EBER）原位杂交检测均阳性；在所有病例中，6例接受手术治疗，8例实施综合治疗，截至随访结束14例患者均存活。结论 PPLEC是一种罕见的肺恶性肿瘤，与EB病毒（Epstein-Barr virus, EBV）感染相关。该疾病可分为Regaud型和Schmincke型，二者在影像学和病理学特征上具有独特差异。在治疗方面，早期以手术治疗为主，中晚期则采取综合治疗，整体预后较好。对于PD-L1高表达的中晚期患者，免疫治疗是一种较为有效的治疗选择。 】 【中文关键词：原发性肺淋巴上皮癌；亚型；预后】.
Keywords: Primary pulmonary lymphoepithelial carcinoma; Prognosis; Subtype.