@article{oai:redcross.repo.nii.ac.jp:00013653,
 author = {Kenji, Yorita and Naoto, Kuroda and Yoshiko, Agatsuma and Yukari, Wada and Masahiko, Ohara and Kaori, Yasuoka and Keiko, Mizuno and Junya, Fukuda and Hideyuki, Nakagawa and Katsushi, Miyazaki and Nobuyuki, Tanida and Nobumasa, Hamaguchi},
 issue = {1},
 journal = {高知赤十字病院医学雑誌, Medical Journal of Kochi Red Cross Hospital},
 month = {Mar},
 note = {Background: Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland
tumor. Histological diagnosis of MECs that exhibit classical histological features is not difficult. However,
diagnosis of some histological variants or high-grade MEC tumors can be challenging because of overlaps
in histological features with other diseases. Recently, chromosomal translocations in salivary gland
tumors have been recognized, and the detection of MAML2 rearrangements can support the pathological
diagnosis of MECs. Recently, MECs without MAML2 rearrangements might be reclassified as hyalinizing
clear cell carcinoma (HCCC) based on the detection of EWSR1 -ATF1 gene fusions. The present study
aimed to investigate the presence of MAML2 and EWSR1 rearrangements in MECs via fluorescence in
situ hybridization (FISH).
Materials and methods: We retrospectively analyzed tumor samples from five MEC patients diagnosed in
our hospital between 2008 to 2015. A total of six tumors from the five cases were pathologically evaluated
and subjected to FISH analysis, which was performed using a MetaSystems image analysis system.
Results: The median age of the patients was 75 years (range: 32-79), with the majority of patients
being male (male to female ratio, 4:1). The localization and pathological classification (histological
grade, histological variant) of the six tumors were parotid gland/low grade/classical histology (n=2),
submandibular gland/low grade/clear cell variant (n=1), lung/high grade (n=1), lung/low grade/classical
(n=1), and maxillary sinus/low grade/clear cell variant (n=1). Less than 10% of the background nonneoplastic
cells showed split signals of MAML2 . Positive MAML2 rearrangements were observed in two
parotid tumors and one maxillary sinus tumor because each tumor showed over 90% of MAML2 split
signals. The other tumors appeared to show equivocal results for MAML2 rearrangement. No EWSR1
rearrangements were detected in all cases, suggesting that HCCC was not present.
Conclusion: FISH was found to be effective for obtaining conclusive MEC diagnoses with small biopsy
samples. However, this method may have a high rate of returning equivocal results, thereby limiting its
use in confirming the presence of gene rearrangements.},
 pages = {23--28},
 title = {Computer-aided automated evaluation of MAML2 and EWSR1 rearrangements in five cases of mucoepidermoid carcinoma: A single-institution study using fluorescence in situ hybridization(和訳中)},
 volume = {22},
 year = {2018}
}