Department of Pathology, Panyu District Central Hospital, Guangzhou, China.
Department of Urology, Panyu District Central Hospital, Guangzhou, China.
Diagn Pathol. 2023 Aug 29;18(1):97. doi: 10.1186/s13000-023-01383-z.
Malakoplakia is a rare inflammatory disease of the urogenital tract. There have been no reports of malakoplakia expressing anaplastic lymphoma kinase (ALK) to date. Here, we present one case of malakoplakia with aberrant ALK expression by immunohistochemistry and discuss the clinical significance.
A 65-year-old Chinese woman with a history of diabetes presented with solid masses in the liver and kidney and elevated lesions on the mucosal surface of the colon. Right nephrectomy and partial liver resection were performed. Microscopically, sheets of histiocytes with poor intercellular adhesion were seen, with Michaelis-Gutmann bodies present in both the intracellular and extracellular interstitium. CD10-, CD68-, and CD163-positive cells were present, with Michaelis-Gutmann bodies confirmed by staining with Alcian blue, periodic acid-Schiff (PAS), periodic acid-Schiff with diastase, Von Kossa, and Prussian blue. Aberrant ALK1 and ALK (D5F3) expression was observed in the cytoplasm and nucleus of cells. However, ALK gene mutation was not detected by fluorescence in situ hybridization or whole exome next-generation sequencing. NGS revealed nine individual somatic gene mutations: GOT1L1, GLIS2, SPOUT1, TMEM97, MUC3A, NSD2, SFXN5, ADAD1 and RAD50. The significance of the somatic gene mutations detected in this study is not clear, and the relationship between them and malakoplakia cannot be clarified by existing scientific studies. The pathological diagnosis was malakoplakia with aberrant ALK expression by immunohistochemistry. The antibiotics imipenem and vancomycin were started based on the results of drug sensitivity analysis and the patient was subsequently discharged. She experienced no discomfort during 30 months of follow-up.
This is the first reported case of malakoplakia with aberrant ALK expression, it should be differentiated from ALK-positive histiocytosis to avoid misdiagnosis.
黏膜黑色素细胞增多症是一种罕见的泌尿生殖道炎症性疾病。目前尚无黏膜黑色素细胞增多症表达间变性淋巴瘤激酶（ALK）的报道。本文报道了一例通过免疫组织化学显示异常ALK 表达的黏膜黑色素细胞增多症病例，并探讨了其临床意义。
一名 65 岁中国女性，有糖尿病病史，表现为肝、肾实质肿块和结肠黏膜表面隆起性病变。行右肾切除术和部分肝切除术。镜下可见细胞间黏附不良的组织细胞片，细胞内外间质均可见 Michaelis-Gutmann 小体。CD10、CD68 和 CD163 阳性细胞，用阿尔辛蓝、过碘酸雪夫（PAS）、PAS 加唾液酸酶、Von Kossa 和普鲁士蓝染色证实 Michaelis-Gutmann 小体的存在。细胞浆和核内观察到异常的 ALK1 和 ALK（D5F3）表达。然而，荧光原位杂交或全外显子组下一代测序未检测到 ALK 基因突变。NGS 显示 9 个个体体细胞基因突变：GOT1L1、GLIS2、SPOUT1、TMEM97、MUC3A、NSD2、SFXN5、ADAD1 和 RAD50。本研究中检测到的体细胞基因突变的意义尚不清楚，且现有科学研究无法阐明它们与黏膜黑色素细胞增多症之间的关系。病理诊断为免疫组织化学显示异常 ALK 表达的黏膜黑色素细胞增多症。根据药敏分析结果开始使用亚胺培南和万古霉素治疗，随后患者出院。在 30 个月的随访中，患者无不适症状。
这是首例报道的异常 ALK 表达的黏膜黑色素细胞增多症病例，应与 ALK 阳性组织细胞增多症相鉴别，避免误诊。
