NUT-rearranged sarcoma.

NUT-rearranged sarcoma is an emerging group of soft tissue sarcomas defined by NUT rearrangement. It is distinct from NUT carcinoma. These sarcomas show a predilection for somatic soft tissue, the thoracic region, the gastrointestinal tract, and body cavities, and affect a wide age range. Histologically, they display one or multiple growth patterns within the tumor, including fibrosarcomatous, round cell, epithelioid/rhabdoid, and hyalinized/nested patterns. Tumor cells invariably express NUT (with the exception of tumors harboring NUTM2) and may have aberrant expression of other markers. Molecularly, NUT-rearranged sarcoma typically involves genes in the MAD transcription family. Those NUT-rearranged sarcomas seem to have distinct clinical and pathologic features. While BET inhibitors are effective in NUT carcinoma, they may not be effective in NUT-rearranged sarcoma.