MiT family translocation carcinomas of the kidney and related entities

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• The MiT family of transcription factors, including TFE3 and TFEB, are implicated in specific renal cell carcinoma (RCC) subtypes.
• Gene fusions involving TFE3 and TFEB characterize distinct RCCs, such as Xp11 translocation RCC and t(6;11) translocation RCC.
• These RCC subtypes exhibit morphologic similarities and shared downstream targets due to the overlapping functions of TFE3 and TFEB.

Purpose of the Study:

• To review current knowledge on MiT family translocation RCCs.
• To discuss related neoplasms with alterations in TFE3 and TFEB, including TFE3-rearranged PEComas and TFEB-amplified RCC.
• To outline differential diagnostic considerations for these molecularly defined neoplasms.

Main Methods:

• Literature review of molecularly defined neoplasms.
• Analysis of gene fusions and amplifications involving MiT family transcription factors.
• Comparative analysis of morphologic and molecular features of RCC subtypes.

Main Results:

• TFE3 and TFEB gene fusions define specific RCC subtypes with overlapping features.
• MiT family translocation RCCs, TFE3-rearranged PEComas, and TFEB-amplified RCC represent a spectrum of related neoplasms.
• Understanding these molecular alterations is crucial for accurate diagnosis.

Conclusions:

• MiT family translocation RCCs are a distinct group of neoplasms characterized by TFE3 or TFEB alterations.
• Related entities like TFE3-PEComas and TFEB-amplified RCC expand the spectrum of MiT family-driven tumors.
• Accurate diagnosis relies on integrating molecular findings with clinicopathologic features.