Servizio di Istopatologia e Citodiagnosi, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, 00168, Rome, Italy.
Institute of Pathology, Università Cattolica del Sacro Cuore, Roma, Italy.
BMC Cancer. 2019 Aug 2;19(1):763. doi: 10.1186/s12885-019-5981-x.
Bladder leiomyosarcoma is the most frequent mesenchymal neoplasm of the bladder. However, the rarity of the disease and some morphological aspects could give serious problems to differential diagnosis.
A 86-year-old male patient was referred to our institution to undergo endoscopic low-urinary-tract re-evaluation 2 months after the detection of a "low-grade urothelial neoplasia" in urinary cytology. A TURBT (transurethral resection of bladder tumor) was performed and revealed a tumor extending for 3.5 cm with thin stalk peduncle on the left lateral wall of the bladder, cephalad and lateral to the left ureteral orifice. The exophytic part of the tumor was resected with the underlying bladder wall. Histologically, the tumor showed a quite complex pattern, composed of spindle cells, with often invasion to the surrounding bladder muscular wall, and the presence of numerous multinucleated, osteoclast-like giant cells, scattered throughout the neoplasia.
Here we report a unique case of urinary bladder leiomyosarcoma with osteoclast-like multinucleated giant cells (OGCs). These cells, confounding the morphological aspect, indeed showed an immunohistochemical phenotype of non-neoplastic origin (most likely a histiocyte/macrophage differentiation). We feel that the presence of the OGCs within this tumor is reactive. Nevertheless, more research is necessary to understand the role of OGCs in urinary bladder tumors and leiomyosarcoma, in paticular.
膀胱平滑肌肉瘤是膀胱最常见的间叶性肿瘤。然而，由于该病罕见，且存在一些形态学特征，可能会给鉴别诊断带来严重问题。
一名 86 岁男性患者因尿细胞学检查发现“低级别尿路上皮肿瘤”，在 2 个月后被转诊至我院进行内镜下下尿路再评估。进行了经尿道膀胱肿瘤切除术（TURBT），发现肿瘤位于膀胱左侧侧壁，呈 3.5cm 长的细茎状蒂，位于左输尿管口上方和外侧。肿瘤的外生部分与膀胱壁的下层一起被切除。组织学上，肿瘤显示出一种相当复杂的模式，由梭形细胞组成，常侵犯周围膀胱肌肉壁，并存在许多散在分布于肿瘤中的多核、破骨样巨细胞。
我们在此报告一例罕见的具有破骨样多核巨细胞（OGC）的膀胱平滑肌肉瘤。这些细胞使形态学方面变得复杂，但实际上表现出非肿瘤起源的免疫组织化学表型（最有可能是组织细胞/巨噬细胞分化）。我们认为，这些肿瘤内的 OGC 是反应性的。然而，仍需要更多的研究来了解 OGC 在膀胱肿瘤和平滑肌肉瘤中的作用。
