Ikegami H, Iwasaki H, Ohjimi Y, Takeuchi T, Ariyoshi A, Kikuchi M
Department of Pathology and Urology, School of Medicine, Fukuoka University, Japan.
Hum Pathol. 2000 Mar;31(3):332-40. doi: 10.1016/s0046-8177(00)80247-6.
Sarcomatoid carcinoma of the urinary bladder is a rare entity, in which both the histogenesis and biological behavior remain controversial. We herein describe the clinicopathologic and immunohistochemical profiles of sarcomatoid carcinomas and discuss the significance of cell adhesion molecules in the development of this peculiar neoplasm. The authors examined formalin-fixed and paraffin-embedded tissue samples from 14 patients with sarcomatoid carcinoma of the urinary bladder. An immunohistochemical analysis was performed by using antibodies against epithelial and mesenchymal antigens as well as adhesion molecules. Most patients suffered from an advanced stage of the tumor, extending to the muscular layer (7 cases) or to the perivesical tissues (5 cases). Microscopically, all 14 tumors were composed predominantly of a carcomatoid component and an obviously carcinomatous component. The sarcomatoid component was composed of a mixture of spindle cells, round cells, and pleomorphic giant cells. The carcinomatous components consisted of papillary or nonpapillary high-grade transitional cell carcinoma (TCC). The zones of gradual transition between the carcinomatous and the sarcomatous elements were focally apparent in each tumor. The findings of an immunohistochemical examination indicated that both carcinomatous and sarcomatoid components expressed epithelial antigens (pankeratin or EMA), even though the staining pattern varied from case to case. As for cell adhesion molecules, the carcinomatous components were positive for E-cadherin (8 of 12), CD44s (8 of 12), and CD44v6 (6 of 12). Although the sarcomatoid components were also positive for E-cadherin (5 of 12), CD44s (4 of 12), and CD44v6 (3 of 12), these rates were lower than those in the carcinomatous components. Six patients died of their disease between 5 and 36 months after the diagnosis was made. The recognition of sarcomatoid carcinomas has important therapeutic and prognostic implications. It seems appropriate to treat these neoplasms in the same manner as conventional high-grade TCCs with similar degrees of invasion. We consider that sarcomatoid carcinomas should be regarded as a high-grade carcinoma that shows a prominent pseudosarcomatous dedifferentiation. The sarcomatoid component of sarcomatoid carcinomas may result from either anaplastic changes or dedifferentiation related to the process of losing cell adhesion molecules.
膀胱肉瘤样癌是一种罕见的疾病，其组织发生和生物学行为仍存在争议。我们在此描述膀胱肉瘤样癌的临床病理和免疫组化特征，并讨论细胞黏附分子在这种特殊肿瘤发生发展中的意义。作者检查了14例膀胱肉瘤样癌患者的福尔马林固定石蜡包埋组织样本。使用针对上皮和间充质抗原以及黏附分子的抗体进行免疫组化分析。大多数患者肿瘤处于晚期，已侵犯肌层（7例）或膀胱周围组织（5例）。显微镜下，所有14个肿瘤主要由肉瘤样成分和明显的癌成分组成。肉瘤样成分由梭形细胞、圆形细胞和多形性巨细胞混合组成。癌成分由乳头状或非乳头状高级别移行细胞癌（TCC）组成。在每个肿瘤中，癌成分和肉瘤样成分之间的逐渐过渡区域局部可见。免疫组化检查结果表明，癌成分和肉瘤样成分均表达上皮抗原（全角蛋白或EMA），尽管染色模式因病例而异。至于细胞黏附分子，癌成分中E-钙黏蛋白（12例中的8例）、CD44s（12例中的8例）和CD44v6（12例中的6例）呈阳性。虽然肉瘤样成分中E-钙黏蛋白（12例中的5例）、CD44s（12例中的4例）和CD44v6（12例中的3例）也呈阳性，但这些比例低于癌成分中的比例。6例患者在诊断后5至36个月死于该病。认识膀胱肉瘤样癌具有重要的治疗和预后意义。以与侵袭程度相似的传统高级别TCC相同的方式治疗这些肿瘤似乎是合适的。我们认为膀胱肉瘤样癌应被视为一种表现出明显假肉瘤样去分化的高级别癌。膀胱肉瘤样癌的肉瘤样成分可能源于间变或与细胞黏附分子丢失过程相关的去分化。
