147O Scope of NUT carcinomas (NC): An international multicentric study

NC represents a rare malignancy with a devastating prognosis. It's produced by the rearrangement of the NUTM1 gene, affecting people of all ages and arising from different localisations, the thoracic being the most common. Due to its rarity and heterogeneity, there is no standard of care for NC and most of the evidence comes from retrospective series. Ambispect multicentric international study for the clinical and therapeutic characterisation of NC. The primary endpoint is to describe first-line treatment and survival in a non-curative and curative setting. Secondary endpoints are to describe baseline characteristics and prognostic. Characteristics will be defined in terms of frequency, median with confidence intervals. The Kaplan-Meier estimate stratified by treatment type will be applied. 51 patients (28 from France, 10 Spain, 6 Poland, 5 United States, 1 Greece, and 1 Peru) have been included. The median age was 34 years and 60% were men. The most common partner of fusion was BRD4 (23%), and the thoracic area was the most frequent primary site (51%), followed by the head and neck (45%). 16% of the patients had localised disease, 37% locally advanced, and 47% metastatic. 51% of the patients were in the poor prognostic group, while 10% and 4% had intermediate and good prognostic. 25 patients underwent a curative intention approach and 26 underwent palliative treatment. The median number of treatment lines was 2. With a median follow-up of 27 months, in the whole population, median overall survival (OS) was 9 months (95%CI 6.4-20.4). OS and Progression Free Survival (PFS) for each type of treatment is summarized in the table. Table: 147ONPFS (months)OS (months)Median (95%CI)Median (95%CI)Curative253.8 (2.5-7.4)8.7 (4.8-20.4)Surgery42.1 (0.4-2.5)NRChemoradiotherapy106.7 (1.2-7.6)9.0 (3.9-NR)Multimodal approach115.2 (2.9-8.7)5.7 (2.1-9.3)Palliative264.0 (3.6-8.1)9.4 (5.6-22.0)Chemotherapy83.9 (1.7-52.1)6.4 (1.9-22.0)BET inhibitors84.3 (1.0-17.1)5.6 (1.1-29.4)Chemo-immunotherapy84.8 (0.2-8.8)21.3 (6.7-26.5)Immunotherapy25.4 (3.6-7.1)19.4 (9.4-29.3) Open table in a new tab The multidisciplinary approach represents a cornerstone of curative treatment. Chemoimmunotherapy could have a potential role in the metastatic setting. The International Registry is a powerful tool in rare tumours such as NC.