透明细胞牙源性癌（CCOC）是一种牙源性癌，其特征是空泡和透明细胞的片状和岛状。当肿瘤细胞偏离其特征性的清晰形态时，即使借助基因分析来识别 CCOC，非典型 CCOC 的诊断也会构成挑战。在这篇手稿中，我们详细介绍了复发性透明细胞牙源性癌 (CCOC) 的首个病例64 岁男性有明显的鳞状分化。该个体的原发性肿瘤最初表现出双相透明细胞表型。然而，在第三次复发后，透明的肿瘤细胞完全被表皮样细胞取代，其特征是嗜酸性细胞质、囊泡染色质和突出的核仁。注意到显着的侵袭性特征，例如坏死、明显的细胞学恶性肿瘤、神经周围播散和血管侵犯。此外，肿瘤进展为明显的肺转移。肿瘤细胞对 AE1/AE3、KRT19、Pan-CK、EMA、P40、P63、CK34βE12 和 P53 表现出阳性免疫反应性，而对 CK35βH11、KRT7、S-100 和神经内分泌标志物检测呈阴性。 Ki-67增殖指数经计算平均为15%。此外，FISH 分析揭示了 EWSR1::ATF1 基因融合的存在。该病例说明了一种罕见且侵袭性的 CCOC 病例，其特征是肿瘤复发后出现显着的鳞状分化。© 2024。作者。

Clear cell odontogenic carcinoma (CCOC) is an odontogenic carcinoma characterized by sheets and islands of vacuolated and clear cells. The diagnosis of atypical CCOC can pose a challenge when tumor cells deviate from their characteristic clear morphology, even with the aid of genetic profiling for CCOC identification.In this manuscript, we detailed the inaugural instance of a recurrently recurring clear cell odontogenic carcinoma (CCOC) with pronounced squamous differentiation in a 64-year-old male. The primary tumor in this individual initially displayed a biphasic clear cell phenotype. However, subsequent to the third recurrence, the clear tumor cells were entirely supplanted by epidermoid cells characterized by eosinophilic cytoplasm, vesicular chromatin, and prominent nucleoli. Notable aggressive attributes such as necrosis, conspicuous cytological malignancy, perineural dissemination, and vascular invasion were noted. Additionally, the tumor progressed to manifest lung metastases. The tumor cells exhibited positive immunoreactivity for AE1/AE3, KRT19, Pan-CK, EMA, P40, P63, CK34βE12, and P53, while they tested negative for CK35βH11, KRT7, S-100, and neuroendocrine markers. The Ki-67 proliferation index was calculated at an average of 15%. Furthermore, FISH analysis unveiled the presence of the EWSR1::ATF1 gene fusion.This case illustrated a rare and aggressive case of CCOC characterized by significant squamous differentiation upon recurrence of the tumor.© 2024. The Author(s).