Tao Sirong, Zhang Yan, Wang Wei, He Ying, Jiang Lili
Department of Pathology, West China Second University Hospital, Sichuan University, Chengdu, China.
Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, West China Second University Hospital, Sichuan University, Chengdu, China.
Front Oncol. 2025 Jul 31;15:1573747. doi: 10.3389/fonc.2025.1573747. eCollection 2025.
Müllerian papilloma is a rare benign genital tract tumor, and its malignant transformation is extremely rare. Due to its complex and diverse pathological morphological manifestations, it is prone to misdiagnosis.
We reported the malignant transformation of Müllerian papilloma into endometrioid carcinoma in two young girls, along with their pathological results. For the first time, we combined next-generation sequencing (NGS) technology to explore the molecular characteristics.
The two cases of malignant transformation into endometrioid adenocarcinoma exhibited similar pathological morphology and immunohistochemical (IHC) markers. Morphologically, they presented complex and diverse features. The benign areas showed a mild papillary structure, while the malignant areas displayed complex papillary branches, cribriform patterns, and solid structures, accompanied by hemorrhage, necrosis, and interstitial inflammatory cell infiltration. In terms of IHC, CK7 and EMA were either focally positive or diffusely positive; Vimentin, P16, and SALL-4 were negatively expressed; P53 showed wild-type expression; the ki67 proliferation index was 35-45%. Subsequent sequencing revealed a low tumor mutation burden and stable microsatellites. However, three novel fusion genes were identified.
The malignant transformation of Müllerian papilloma is extremely rare, with complex and diverse morphological manifestations. High vigilance is required during diagnosis to avoid confusion with sarcomas. This tumor has a low tumor mutation burden and stable microsatellites, and the exact mechanism of malignant transformation requires further investigation.
苗勒管乳头状瘤是一种罕见的良性生殖道肿瘤，其恶变极为罕见。由于其病理形态表现复杂多样，容易误诊。
我们报告了两名年轻女孩的苗勒管乳头状瘤恶变为子宫内膜样癌的病例及其病理结果。首次结合二代测序（NGS）技术探索其分子特征。
两例恶变为子宫内膜样腺癌的病例表现出相似的病理形态和免疫组化（IHC）标志物。形态学上，它们呈现出复杂多样的特征。良性区域表现为轻度乳头状结构，而恶性区域则显示出复杂的乳头状分支、筛状结构和实性结构，伴有出血、坏死和间质炎性细胞浸润。免疫组化方面，CK7和EMA呈局灶性阳性或弥漫性阳性；波形蛋白、P16和SALL-4呈阴性表达；P53呈野生型表达；ki67增殖指数为35%-45%。随后的测序显示肿瘤突变负荷较低且微卫星稳定。然而，鉴定出了三个新的融合基因。
苗勒管乳头状瘤的恶变极为罕见，形态表现复杂多样。诊断时需要高度警惕，避免与肉瘤混淆。该肿瘤肿瘤突变负荷低且微卫星稳定，恶变的确切机制需要进一步研究。
