Metastatic NUT Midline Carcinoma

Introduction: NUT midline carcinoma (NMC) is a rare carcinoma that presents with rearrangement to the NUTM1 (aka NUT) gene affecting all ages, but predominantly teens and young adults. Mainly reported in pathology and oncology literature, this highly lethal cancer is presumably under-recognized and may account for varying undifferentiated neoplasms. Typically, NMC presents in the midline upper airway regions of the head, neck, and thorax, with few reported cases including the solid organs and intramuscular locations. There is no gold standard for the diagnosis and treatment of NUT carcinoma to date. This educational exhibit will report the FDG PET/CT findings of metastatic NMC.

Methods: Baseline FDG PET/CTs were performed on two patients with biopsy-proven NMC within one month of diagnosis and before therapeutic interventions. Representative images and a brief review of published findings are presented.

Results: In very limited reported FDG PET/CT studies, NMC is noted to be FDG avid. In our two patients, intense FDG uptake is noted in areas of tumor involvement. Additionally, FDG PET/CT was able to identify osseous metastases that were not evident in other cross-sectional imaging studies.

Conclusions: NMC is a rare carcinoma that predominantly affects teens and young adults but can be seen in all ages. Given the rarity and lack of diagnostic standards, increasing awareness of this unusual and deadly disease is essential.