Huang L L, Shang Z X, Han Y C
Department of Pathology, Shanghai Chest Hospital/Chest Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200030, China.
Zhonghua Bing Li Xue Za Zhi. 2024 Nov 8;53(11):1117-1121. doi: 10.3760/cma.j.cn112151-20240508-00301.
To investigate the clinicopathological features and differential diagnosis of primary pulmonary hyalinizing clear cell carcinoma (HCCC), as well as its diagnostic pitfalls in assessing biopsy specimens. Five cases of primary pulmonary HCCC diagnosed in the Department of Pathology, Shanghai Chest Hospital, Shanghai, China from August 2019 to December 2023 were collected. The clinicopathological characteristics, immunohistochemistry, and the EWSR1 gene related translocation and fusion were summarized, and relevant literature was reviewed. Among the five cases of HCCC, two were males and three were females, with ages ranging 36-74 years. The tumors were located in the lumen of the bronchus or trachea and showed an exophytic polypoid growth pattern. The maximum diameter of the tumors ranged from 1.3 to 5.0 cm. Histologically, the tumor cells showed transparent cytoplasm and slight cellular atypia, with medium-sized round cells arranged in cords, nests, and trabecula. Small nucleoli were noted, while mitotic figures were rare. The interstitial bands of the tumor in various thickness were anastomosed with hyalining and sclerosing fibrous tissues. All the tumor cells were positive for CKpan, CK7, p40, p63 and CK5/6, but negative for S-100, SMA, Calponin, TTF1 and Napsin A; Ki-67 proliferation index was less than 10% (1%-10%). FISH testing showed EWSR1 gene translocation in all cases, three of which were confirmed by next generation sequencing to have EWSR1::ATF1 gene fusion. Biopsy specimens of primary HCCC in the lungs are prone to misdiagnosis due to the expression of squamous cell carcinoma biomarkers, which poses a unique challenge. A complete understanding of the morphological characteristics of primary pulmonary HCCC, combined with immunohistochemistry and molecular testing, is helpful to reach accurate diagnosis.
探讨原发性肺透明变性透明细胞癌（HCCC）的临床病理特征、鉴别诊断及其在评估活检标本时的诊断陷阱。收集了2019年8月至2023年12月在中国上海胸科医院病理科诊断的5例原发性肺HCCC。总结其临床病理特征、免疫组化以及EWSR1基因相关易位和融合情况，并复习相关文献。5例HCCC中，男性2例，女性3例，年龄36 - 74岁。肿瘤位于支气管或气管腔内，呈外生性息肉样生长模式。肿瘤最大直径为1.3至5.0 cm。组织学上，肿瘤细胞胞质透明，细胞异型性轻微，中等大小的圆形细胞呈条索状、巢状和小梁状排列。可见小核仁，而有丝分裂象罕见。肿瘤的间质带厚度不一，与透明变性和硬化性纤维组织吻合。所有肿瘤细胞CKpan、CK7、p40、p63和CK5/6均呈阳性，但S - 100、SMA、钙调蛋白、TTF1和Napsin A均为阴性；Ki - 67增殖指数小于10%（1% - 10%）。FISH检测显示所有病例均有EWSR1基因易位，其中3例经二代测序证实存在EWSR1::ATF1基因融合。由于肺原发性HCCC活检标本中存在鳞状细胞癌生物标志物的表达，容易误诊，这带来了独特的挑战。全面了解原发性肺HCCC的形态学特征，结合免疫组化和分子检测，有助于做出准确诊断。
