CRTC1-MAML2 gene fusion in mucoepidermoid carcinoma of the lacrimal             gland.
Epithelial tumors of the lacrimal gland are histologically similar to salivary             gland tumors. Here we report on a rare case of mucoepidermoid carcinoma (MEC)             in a 73‑year-old man with a swelling of the left lacrimal gland. The tumor had             a microscopic appearance consistent with a classical low-grade MEC of the lacrimal             gland. There were no signs of recurrence or metastases during a five-year follow-up.             Using RT-PCR and FISH we demonstrated that the tumor was positive for the CRTC1-MAML2             gene fusion previously shown to be associated with in particular low-grade salivary             MECs with favorable prognosis. By immunohistochemistry we showed that the majority             of tumor cells, including epidermoid, intermediate and mucous producing cells,             expressed the CRTC1-MAML2 fusion protein. In contrast, 15 non-MEC lacrimal neoplasm             were fusion-negative. Our findings show that lacrimal MEC is not only clinically             and morphologically but also genetically identical to MECs originating from other             exocrine glands, including those of the lung, thyroid, cervix and salivary glands.             Taken together, the present and previous studies further emphasize the fundamental             biologic and genetic similarities among MECs developing from different anatomical             sites and organs. Moreover, our findings indicate that the CRTC1-MAML2 fusion             may be a useful diagnostic and prognostic biomarker for lacrimal MEC.
Institute of Neuroscience and Pharmacology, Eye Pathology Section,                     Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
Sarah Linéa
SL
Von Holstein
André
A
Fehr
Steffen
S
Heegaard
Marianne Hamilton
MH
Therkildsen
Göran
G
Stenman
D000165:Acridine Orange; D000368:Aged; D018277:Carcinoma, Mucoepidermoid / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005134:Eye Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D015870:Gene Expression; D006801:Humans; D007765:Lacrimal Apparatus / Q000473:pathology; D008297:Male; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D015514:Oncogene Proteins, Fusion / Q000235:genetics* / Q000378:metabolism; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
C500984:CRTC1 protein, human; D004268:DNA-Binding Proteins; C471297:MAML2 protein, human; D009687:Nuclear Proteins; D015514:Oncogene Proteins, Fusion; D015534:Trans-Activators; D014157:Transcription Factors; D000165:Acridine Orange