BACKGROUND Membranous nephropathy is the most common glomerular disease related to malignancy. However, it is difficult to distinguish between true malignancy-related membranous nephropathy and idiopathic membranous nephropathy coincident with cancer. It has been reported that phospholipase A2 receptor (PLA2R) is the first autoantigen involved in idiopathic membranous nephropathy and thrombospondin type-1 domain-containing 7A (THSD7A) may have a close relationship with malignancy-related membranous nephropathy. Therefore, the aim of this study was to compare the clinicopathological characteristics between membranous nephropathy patients with cancer and idiopathic membranous nephropathy patients without cancer to better detect malignancy-related membranous nephropathy, including glomerular PLA2R and THSD7A depositions and their circulating antibodies, together with glomerular IgG4 deposition. METHODS Twelve membranous nephropathy patients with cancer and 257 idiopathic membranous nephropathy patients without cancer were included in this study and had been followed up for more than 1 year. The glomerular expression of PLA2R, THSD7A, and IgG4 was analyzed by immunohistochemistry. Circulating anti-PLA2R and anti-THSD7A antibodies were assessed by enzyme-linked immunosorbent assay and indirect immunofluorescence testing, respectively. RESULTS Membranous nephropathy patients with cancer were significantly older and had higher serum creatinine and a lower estimated glomerular filtration rate than idiopathic membranous nephropathy patients (P<0.05). The positive rates of glomerular PLA2R and IgG4 depositions and circulating anti-PLA2R antibodies in membranous nephropathy patients with cancer were significantly lower than those in idiopathic membranous nephropathy patients without cancer (P<0.01). CONCLUSION The absence of glomerular PLA2R deposition and negative circulating anti-PLA2R antibodies, along with negative glomerular IgG4 staining, may be useful clues to more accurately screen underlying malignancies in membranous nephropathy patients.

中文翻译：

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膜性肾病伴癌症的临床病理学特征：回顾性单中心研究和文献综述。

背景技术膜性肾病是与恶性肿瘤相关的最常见的肾小球疾病。然而，很难区分真正的恶性肿瘤相关膜性肾病和与癌症同时发生的特发性膜性肾病。据报道，磷脂酶A2受体（PLA2R）是第一个参与特发性膜性肾病的自身抗原，含有血小板反应蛋白1型结构域的7A（THSD7A）可能与恶性肿瘤相关的膜性肾病关系密切。因此，本研究的目的是比较膜性肾病伴癌症患者和特发性膜性肾病非癌症患者的临床病理特征，以更好地检测恶性肿瘤相关的膜性肾病，包括肾小球 PLA2R 和 THSD7A 沉积及其循环抗体，以及肾小球 IgG4 沉积。方法 12例膜性肾病伴癌患者和257例非癌特发性膜性肾病患者纳入本研究，随访1年以上。通过免疫组织化学分析PLA2R、THSD7A和IgG4的肾小球表达。分别通过酶联免疫吸附测定和间接免疫荧光测试评估循环抗PLA2R和抗THSD7A抗体。结果 与特发性膜性肾病患者相比，膜性肾病合并癌症的患者年龄更大，血清肌酐更高，估计肾小球滤过率更低（P<0.05）。膜性肾病伴癌患者肾小球PLA2R、IgG4沉积及循环抗PLA2R抗体阳性率显着低于非癌性特发性膜性肾病患者（P<0.01）。结论 无肾小球 PLA2R 沉积和循环抗 PLA2R 抗体阴性，以及肾小球 IgG4 染色阴性，可能是更准确筛查膜性肾病患者潜在恶性肿瘤的有用线索。