Goldfaden Joshua S, Kim Seungwon, Seethala Raja R
Oral and Maxillofacial Pathology Resident, Department of Diagnostic Sciences, School of Dental Medicine, University of Pittsburgh, G-132 Salk Hall, 3501 Terrace Street, Pittsburgh, PA, 15261, USA.
Department of Otolaryngology, University of Pittsburgh, #300 Presbyterian University Hospital, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
Head Neck Pathol. 2025 Mar 26;19(1):41. doi: 10.1007/s12105-025-01774-2.
Mucoepidermoid carcinoma (MEC) typically occurs in isolation. We report an unusual case of MEC coexisting with an intercalated duct lesion (IDL), both harboring MAML2 rearrangements.
An 82-year-old male with a left parotid mass underwent superficial parotidectomy.
Microscopic examination of immunohistochemical stains and fluorescence in situ hybridization (FISH) studies were performed.
The parotid demonstrated an intermediate grade MEC and an adjacent IDL with the typical abluminal ΔNp63 (p40) and ductal SOX-10 immunopositivity, but absent LEF-1 and nuclear β-catenin staining. FISH confirmed MAML2 rearrangements in both lesions.
This case expands the spectrum of IDL-associated tumors and suggests IDLs may serve as MEC precursors.
黏液表皮样癌（MEC）通常孤立发生。我们报告了一例罕见的MEC与闰管病变（IDL）共存的病例，二者均存在MAML2重排。
一名82岁左侧腮腺肿物男性接受了腮腺浅叶切除术。
进行了免疫组织化学染色和荧光原位杂交（FISH）研究的显微镜检查。
腮腺显示为中级MEC和相邻的IDL，具有典型的腔外ΔNp63（p40）和导管SOX-10免疫阳性，但LEF-1和核β-连环蛋白染色阴性。FISH证实两个病变均存在MAML2重排。
该病例扩展了与IDL相关肿瘤的范围，并提示IDL可能是MEC的前体。
