肉瘤样癌（SC）是一种可以出现在任何器官中的罕见疾病。为了阐明SC在器官之外的共同特征，我们评估了通过单一组织学标准定义的SC的临床病理学和免疫学特征，并与随机匹配的经典癌症（非SC）进行了比较，对疾病分期进行了调整。免疫学特征通过多重免疫组织化学评估，比较肿瘤组织中的免疫细胞密度和肿瘤PD-L1表达。我们在我院手术期间（1997-2020年）的7197名患者中确定了101名SC或非SC患者（31名肺部，19名食道，22名胰腺，15名肝脏，4名胆道，6名肾脏，2名子宫和2名卵巢）。SC与较差的生存率显著相关（HR：1.571，95% CI：1.084-2.277，P = .017）。术后6个月内进展的频率在SC患者中显著较高（54％vs 28％，P = .002）。免疫分析显示，CD8 + T细胞密度（130 vs 72个细胞/ mm2; P = .004），肿瘤相关巨噬细胞（566 vs 413个细胞/ mm2; P <.0001）和肿瘤PD-L1表达评分（40％vs 5％; P <.0001）在SC中显著高于非SC。在73例术后进展的SC患者中，多元Cox回归分析显示免疫疗法在生存率方面有可能与有利关联（HR：0.256；95％CI：0.062-1.057; P = .060）。总之，SC在不同器官中共享临床病理学和免疫学特征。我们的研究可以提供SC的病理学定义规范和该罕见疾病的跨器官研究和开发的合理性基础。 © 2023 UICC.

Sarcomatoid carcinoma (SC), which can occur in any organ, is a rare disease. To elucidate common characteristics of SC beyond organs, we evaluated clinicopathological and immunological features of SC defined by the single histological criterion beyond organs compared to randomly matched conventional carcinoma (non-SC) adjusted for the disease stage. Immunological features were assessed by multiplex immunohistochemistry, comparing immune cell density in tumor tissues and tumor programmed death-ligand 1 (PD-L1) expression. A total of 101 patients with SC or non-SC (31 lung, 19 esophagus, 22 pancreas, 15 liver, 4 bile duct, 6 kidney, 2 uterus and 2 ovary) were identified among 7197 patients who underwent surgery at our institute (1997-2020). SC was significantly associated with worse survival (HR: 1.571; 95% CI: 1.084-2.277; P = .017). The frequency of postoperative progression within 6 months was significantly higher for SC patients (54% vs 28%; P = .002). The immune profiling revealed the densities of CD8+ T cells (130 vs 72 cells/mm2 ; P = .004) and tumor-associated macrophages (566 vs 413 cells/mm2 ; P < .0001) and the tumor PD-L1 expression score (40% vs 5%; P < .0001) were significantly higher in SCs than in non-SCs. Among 73 SC patients with postoperative progression, multivariate Cox regression analysis showed that immunotherapy tended to be associated with favorable survival (HR: 0.256; 95% CI: 0.062-1.057; P = .060). Collectively, SCs shared clinicopathological and immunological features across organs. Our study can initiate to standardize the pathological definition of SC and provide a rationale for the investigation and development for this rare disease in a cross-organ manner.© 2023 UICC.