Other epithelial tumors

2023-05-17   Paola Dal Cin, PhD , Yin (Rex) Hung, MD 

1.Brigham and Women's Hospital , Harvard Medical School, Boston , MA (USA)
2.Massachussetts General Hospital,Harvard Medical School, Boston (MA)

Classification

Definition

Two recently described and molecularly defined aggressive lung neoplasms includes NUT carcinoma, characterized mainly by a t(15;19)(q15;p13) associated to BRD4::NUTM1 fusion,1-3 and thoracic SMARCA4-deficient undifferentiated tumor. 4-6

Other epithelial tumorsGenetic marker(s)
NUT carcinomaNUT carcinoma, previously known as NUT midline carcinoma, carries a t(15;19)(q15;p13)} associated to BRD4::NUTM1 fusion in 70% of the cases. Different NUTM1, alias NUTM1, gene partners have bee described in the remaining cases, such as BRD3, NSD3, ZNF532, or ZNF592. 2 Notably, all these non-BRD4 fusion genes interact with BRD4 as part of a complex that regulates epigenetics and transcription.2 The confirmation of NUTM1 rearrangement or chromosomal translocation t(15;19) can be made by cytogenetic analysis, in situ hybridization (FISH), RT-PCR, or next-generation sequencing, if the diagnosis is suspected despite a negative immunostaining for NUT, 3 although NUT immunohistochemistry is fairly sensitive and specific. 7 Three risk groups were defined by anatomic site and NUTM1 gene partner: best prognosis in patients with non-thoracic primary with non-BRD4 partner gene, followed by non-thoracic primary with BRD4 partner gene, and worst survival in thoracic NUT carcinoma patients, regardless of the gene partne. 8
Thoracic SMARCA4-deficient undifferentiated tumor (SMARCA4-UT)Thoracic SMARCA4-UT, previously as known as "SMARCA4-deficient thoracic sarcoma", is a high-grade malignant tumor frequently shows rhabdoid or plasmacytoid cytomorphology but generally imparts an undifferentiated appearance. Many cases of SMARCA4-UT are considered as smoking-related malignancy 4,5,9. SMARCA4-UT is characterized genetically by the presence of inactivating SMARCA4 mutations, such as nonsense or frame-shift mutations, and SMARCA4-UT frequently also harbors alterations with loss of SMARCA2. Loss of SMARCA4 encoded by SMARCA4 can be detected by immunohistochemistry. SMARCA4-UT is characterized by frequent presence of smoking-related mutational signature, high mutation burden, and frequent TP53 mutation, with a subset of tumors that can harbor other non-small cell lung carcinoma-associated mutations such as KRAS, STK11, and KEAP1. 4 The transcriptional profiles of thoracic SMARCA4-UT appear distinct from those of conventional non-small cell lung carcinomas with SMARCA4 deficiency but similar to those of malignant rhabdoid tumors.10

Article Bibliography

Reference NumberPubmed IDLast YearTitleAuthors
1260011442015Primary Pulmonary NUT Midline Carcinoma: Clinical, Radiographic, and Pathologic Characterizations.Sholl LM et al
2303626542018NUT Carcinoma: Clinicopathologic features, pathogenesis, and treatment.French CA et al
3341766982021NUT carcinoma of the lung.Lantuejoul S et al
4317516812020SMARCA4-Deficient Thoracic Sarcomatoid Tumors Represent Primarily Smoking-Related Undifferentiated Carcinomas Rather Than Primary Thoracic Sarcomas.Rekhtman N et al
5319880012020Clinicopathologic Characteristics of BRG1-Deficient NSCLC.Dagogo-Jack I et al
6356186272022Efficacy of Immune Checkpoint Inhibitors in SMARCA4-Deficient Thoracic Tumor.Shinno Y et al
7193634412009Diagnosis of NUT midline carcinoma using a NUT-specific monoclonal antibody.Haack H et al
8323285622020An Anatomical Site and Genetic-Based Prognostic Model for Patients With Nuclear Protein in Testis (NUT) Midline Carcinoma: Analysis of 124 Patients.Chau NG et al
9371153432023Thoracic SMARCA4-deficient undifferentiated tumor.Jiang J et al
10263433842015SMARCA4 inactivation defines a group of undifferentiated thoracic malignancies transcriptionally related to BAF-deficient sarcomas.Le Loarer F et al

Citation

Paola Dal Cin, PhD ; Yin (Rex) Hung, MD

Other epithelial tumors

Atlas Genet Cytogenet Oncol Haematol. 2023-05-17

Online version: http://atlasgeneticsoncology.org/solid-tumor/209154/other-epithelial-tumors