ALK, NUT, and TRK Do Not Play Relevant Roles in Gastric Cancer-Results of an Immunohistochemical Study in a Large Series.

ALK, NUT, and TRK are rare molecular aberrations that are pathognomonic for specific rare tumors. In low frequencies, however, they are found in a wide range of other tumor entities. This study aimed to investigate the frequency, association with clinicopathological characteristics, and prognosis of the immunohistochemical expressions of ALK, NUT, and TRK in 477 adenocarcinomas of the stomach and gastroesophageal junction. Seven cases (1.5%) showed an expression of TRK. In NGS, no NTRK fusion was confirmed. No case with ALK or NUT expression was detected. ALK, NUT, and NTRK expression does not seem to play an important role in gastric carcinomas.