Pulmonary adenoid cystic carcinoma: molecular characteristics and literature review.

BACKGROUND: Pulmonary adenoid cystic carcinoma (PACC) is an exceptionally rare salivary gland-type malignant neoplasm. Because of its clinical manifestations, imaging features are not different from other types of non-small cell lung cancer, which is a diagnostic challenge for most doctors. CONCLUSIONS: A review of the literature shows that high amounts of immunohistochemical (IHC) markers, such as CK7, CD117, P63, SMA, CK5/6, and S-100 are helpful for PACC diagnosis. Surgical resection is the main treatment of PACC, but treatment options for advanced PACC patients are limited and the research of molecular targeted drugs is ongoing in advanced cases not eligible for surgery. Currently, research on PACC targeted therapy mainly focuses on the exploration of v-myb avian myeloblastosis virus oncogene homolog (MYB) and its downstream target genes. In addition, median tumor mutation burden and PD-1/PD-L1 were lower in PACC, which may indicate poor efficacy of immunotherapy in PACC patients. This review focuses on the pathologic features, molecular characteristics, diagnosis, treatment and prognosis of PACC to establish a comprehensive understanding of PACC.

Thoracic SMARCA4-deficient undifferentiated tumor.

Thoracic SMARCA4-deficient undifferentiated tumor (SMARCA4-UT) is a recently described smoking-related malignancy. The pathogenesis of SMARCA4-UT is the mutational inactivation and loss of expression of a subunit encoding the mammalian switch/sucrose nonfermenting ATPase-dependent chromatin remodeling complex (which can be mobilized using adenosine triphosphate hydrolysis nucleosomes and regulate other cellular processes including development, differentiation, proliferation, and apoptosis), in particular SMARCA4 and SMARCA2. The dynamic activity of this complex plays an important role in regulating the activation and repression of gene expression programs. SMARCA4-UT exhibits morphological features similar to the malignant rhabdoid tumor (MRT), small cell carcinoma of the ovary of the hypercalcemic type (SCCOHT), and INI1-deficient tumor, but SMARCA4-UT differs from SCCOHT and MRT from a genomic perspective. SMARCA4-UT mainly involves the mediastinum and lung parenchyma, and appears as a large infiltrative mass that easily compresses surrounding tissues. At present, chemotherapy is a common treatment, but its efficacy is not clear. Moreover, the inhibitor of the enhancer of zeste homolog 2 showed promising efficacy in some patients with SMARCA4-UT. This study aimed to review the clinical characteristics, diagnosis, treatment, and prognosis of SMARCA4-UT.

Contrast-Enhanced Ultrasound Liver Imaging Reporting and Data System in Diagnosing Hepatocellular Carcinoma: Diagnostic Performance and Interobserver Agreement.

OBJECTIVES: To determine the diagnostic performance and inter-reader agreement of the contrast-enhanced ultrasound liver imaging reporting and data system (CEUS-LI-RADS) for diagnosing hepatocellular carcinoma (HCC) in high-risk patients. METHODS: In this prospective study, CEUS-LI-RADS categories (LR-5 for predicting HCC) were assigned by six blinded readers and compared to the definitive HCC diagnosis in patients with liver cirrhosis per the 2017 China Liver Cancer Guidelines (CLCG). CEUS features were recorded in 96 patients with 96 histology-proven lesions. The diagnostic performance of LR-5 was described by the sensitivity, specificity and accuracy. Multi-reader agreement was assessed by using intraclass correlation coefficients (ICC). RESULTS: In cirrhotic patients, the specificity of LR-5 (range: 92.7-100.0 %) was statistically higher than that of CLCG for each reader (range: 28.6-64.3 %). However, the sensitivity (range: 38.6-63.6 %) and accuracy (range: 53.4-70.7 %) were statistically lower in CEUS-LIRADS than in CLCG (sensitivity range: 88.6-100.0 %; accuracy range: 77.6-86.2 %). Only fair to moderate inter-reader agreement was achieved for the CEUS-LI-RADS category (ICC = 0.595) and washout appearance (ICC range: 0.338 to 0.555). Neither nodule-in-nodule nor mosaic architecture was observed more often in HCC (all P > 0.05), with poor inter-reader consistency for both (both ICC < 0.20). CONCLUSION: CEUS-LI-RADS category 5 has a high specificity but a low accuracy for identifying HCC in high-risk patients. Inter-reader agreement is not satisfactory concerning CEUS-LIRADS category and washout appearance. Moreover, the clinical value of ancillary features favoring HCC is quite limited.