Lymphoepithelioma-like carcinoma of the upper urinary tract: A systematic review of case reports

BACKGROUND Lymphoepithelioma-like carcinomas (LELCs) are rare, malignant epithelial tumors, generally considered a subtype of squamous cell carcinoma. LELCs are undifferentiated and can occur in multiple tissues, although LELCs in the urinary tract are extremely rare. As such, evidence does not provide clinicians with guidelines for the best practices. Even though this is a rare disease, it is associated with high morbidity and mortality. Therefore, we must learn to differentiate LELC types and identify risk factors for early identification. AIM To develop an evidence base to guide clinicians treating primary LELCs of the upper urinary tract (UUT-LELC). METHODS We performed a systematic review of all reports on UUT-LELC from the first published case in 1998 until October 2019, according to the PRISMA. A database was then developed by extracting data from previously published reports in order to analyze interactions between clinical characteristics, pathological features, interventions and outcomes. Survival was analyzed using Kaplan–Meier estimates, which were compared using log rank tests. RESULTS A total of 28 previously published cases were identified for inclusion. The median age was 72 years with a male to female ratio of 4:3. Pure type LELCs were most common with 48.3% (n = 14), followed by 37.9% (n = 11) predominant LELCs and 3.4% (n = 1) focal LELCs. Epstein-Barr virus testing was negative in all cases. Fourteen patients received radical nephroureterectomy (RNU)-based intervention. Twenty-three patients survived with no evidence of further metastasis, although six died before the median 18 mo follow-up point. Survival analysis suggests pure histological subtypes, and patients who receive complete tumor resection have more favorable prognoses. As always in cancer care, early identification generally increases the probability of interventional success. CONCLUSION The most effective treatment for UUT-LELC is RNU-based therapy. Since cases are few in number, case reporting must be enhanced and publishing encouraged to both save and prolong lives.

背景 淋巴上皮瘤样癌（LELC）是罕见的恶性上皮性肿瘤，通常被视为鳞状细胞癌的一个亚型。LELC未分化，可发生于多种组织，但泌尿系统的LELC极为罕见。因此，相关证据无法为临床医生提供最佳实践指南。尽管这是一种罕见疾病，但它与高发病率和高死亡率相关。所以，我们必须学会区分LELC的类型，并确定风险因素以便早期识别。 目的 建立一个证据基础，为治疗上尿路原发性LELC（UUT - LELC）的临床医生提供指导。 方法 我们根据PRISMA对1998年首例发表的病例至2019年10月期间所有关于UUT - LELC的报告进行了系统综述。然后通过从先前发表的报告中提取数据建立了一个数据库，以分析临床特征、病理特征、干预措施和结果之间的相互关系。使用卡普兰 - 迈耶估计法进行生存分析，并使用对数秩检验进行比较。 结果 共确定了28例先前发表的病例可纳入研究。中位年龄为72岁，男女比例为4∶3。纯型LELC最为常见，占48.3%（n = 14），其次是占37.9%（n = 11）的优势型LELC和占3.4%（n = 1）的局灶型LELC。所有病例的爱泼斯坦 - 巴尔病毒检测均为阴性。14名患者接受了以根治性肾输尿管切除术（RNU）为基础的干预。23名患者存活且无进一步转移的证据，尽管有6名患者在中位18个月的随访点之前死亡。生存分析表明，纯组织学亚型以及接受完整肿瘤切除的患者预后更佳。在癌症治疗中，一如既往，早期识别通常会增加干预成功的概率。 结论 对UUT - LELC最有效的治疗是以RNU为基础的疗法。由于病例数量较少，必须加强病例报告并鼓励发表，以挽救和延长生命。