EGFR Exon 20 Insertion Mutations in Sinonasal Squamous Cell Carcinoma

Investigating the impact of clinical and genetic factors on the post-surgery prognosis of sinonasal squamous cell carcinoma

Sinonasal squamous cell carcinoma (SNSCC) is an aggressive cancer affecting the nasal and sinus regions, with its progression factors, particularly genetic ones, not yet fully understood. Here, we first conducted a retrospective study with 219 SNSCC patients to identify clinical factors affecting SNSCC prognosis. Additionally, we mined a vast literature dataset to uncover genetic factors associated with SNSCC progression. Based on this data, we constructed SNSCC prognosis pathways and performed a gene set enrichment analysis (GSEA). Clear operative margins were linked to a 73.5-86.3% improvement in overall survival and a 73.5-88.9% lower risk of recurrence. Nasal cavity-originated cases exhibited a 67.6-97.4% decrease in mortality and an 80.7-96.7% lower recurrence rate. Patients at T1-2 staging had a 65.0-80.6% reduced risk of death and recurrence compared to those at T3 stage. Additionally, we identified 53 genes associated with SNSCC, with 14 also implicated in primary tumor site, T stage, and operative margin. These genes, including EGFR, PIK3CA, ERBB2, PTEN, BCL2, BRAF, KRAS, and PRL, form a complex SNSCC-prognosis pathway and were significantly enriched in 42 KEGG pathways and Gene Ontology (GO) terms (FDR-corrected p-value < 0.001), influencing cell growth, apoptosis, and oncogenic signaling pathways. Our study suggests that three clinical parameters (operative margin type, primary tumor site, and T-stage) and 14 genetic factors may influence SNSCC prognosis post-surgery. These findings deepen our understanding of SNSCC and offer potential avenues to enhance its treatment and outcomes.

High 4-1BB Expression in PBMCs and Tumor Infiltrating Lymphocytes (TILs) in Patients with Head and Neck Squamous Cell Carcinoma

OBJECTIVE

 4-1BB is a costimulatory immune-activating molecule. Increased amounts of this protein have previously been found in the plasma of patients with oropharyngeal and oral cancer. Here, we focused on this molecule that functions as part of the immune system. We investigated 4-1BB in the peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TILs) of patients with head and neck squamous cell cancer (HNSCC).

MATERIALS AND METHODS

 The expression level of 4-1BB in the PBMCs was determined using real-time polymerase chain reaction (PCR). The TIMER (Tumor Immune Estimation Resource) web server was utilized to approximate the 4-1BB level in HNSCC TILs. Moreover, 4-1BB immunohistochemistry (IHC) was used to validate TILs in four organs of HNSCC, including oral cancer (OC), oropharyngeal cancer (OPC), sinonasal cancer (SNC), and laryngeal cancer (LC), in both the tumor area and adjacent normal epithelium. The difference in 4-1BB expression levels in various groups was assessed using a Kruskal-Wallis test and an independent sample t-test.

RESULTS

 The level of 4-1BB expression in PBMCs was highest in OPC, followed by OC and healthy controls (HC). Significant differences were discovered between HC and OPC and between OC and OPC. Bioinformatics revealed a substantial correlation between 4-1BB expression level and lymphocyte infiltration in HNSCC, including B cells, CD8+ T cells, and CD4+ T cells. IHC validation in HNSCC tissue revealed that the average number of 4-1BB positive TILs in all four HNSCC subtypes was considerably greater than the number of lymphocytes seen in adjacent normal tissue. Interestingly, the number of lymphocytes that were 4-1BB positive increased in relation to the TIL level.

CONCLUSION

 A higher number of 4-1BB expression levels were found in the PBMCs and TILs of HNSCC patients, implying that 4-1BB may be a promising approach for HNSCC patients to improve their immune function. It is important to study and create a treatment that uses 4-1BB medicine as well as existing drugs.

EGFR exon20 insertion mutations in non-small cell lung cancer: Clinical implications and recent advances in targeted therapies

The advent of targeted therapies for oncogenic mutations has led to a major paradigm shift in the management of non-small cell lung cancer (NSCLC). Molecular targets, such as epidermal growth factor receptor (EGFR)-activating mutations in the region of exons 18 through 21 are the most common oncogenic driver in NSCLC. Classical activating mutations, such as in-frame deletions in exon 19 and point mutations in exon 21 (L858R), are strong predictors for good clinical response to the approved EGFR-tyrosine kinase inhibitors (EGFR-TKIs). However, low frequency mutations occurring within exon 20 (ex20ins) have poorer responses to first/second generation EGFR-TKIs. Moreover, patients with NSCLC harboring EGFR ex20ins are known to have poorer prognosis than those with other EGFR-TKI sensitive mutations, leading to unmet clinical need of novel specific therapeutic options. Rapid changes in molecular diagnostics identifying specific causes have hastened the translation of diagnostic recommendations into clinical practice. Emergence of treatment strategies targeting EGFR ex20ins, such as newer EGFR-TKIs with increased specificity and novel approaches using bispecific monoclonal antibodies, may hold promising therapeutic options in the near future. In this review, we describe the structural, molecular characteristics, and detection strategies of EGFR ex20ins mutations and summarize the latest clinical data on approved treatments and emerging therapies for patients with NSCLC harboring EGFR ex20ins mutations. Further, we will discuss the response heterogeneity of ex20ins mutations to new drugs and acquired drug resistance mechanisms.

An in vitro model and the underlying pathways of sinonasal inverted papilloma development

Recently, the specific association between Sinonasal inverted papilloma (SIP) and EGFR exon 20 mutations has been reported. To investigate the link between specific EGFR mutations and SIP development, we established organotypic raft culture system using nasal polyp-derived immortalized NP2 (iNP2) cells expressing EGFR exon 20 mutants or an exon 19 mutant, and SIP-derived iIP4 cells harboring P772_H773insPYNP mutation. In the raft culture, iIP4 cells showed the inverted growth pattern characteristic to SIP. Interestingly, iNP2 cells expressing EGFR exon 20 duplication mutants, S768_D770dup and N771_H773dup, but not of EGFR exon 19 mutant, E746_A750del, showed the inverted growth pattern. Enhanced activation of the PI3K/AKT signaling pathway was observed in iNP2_S768_D770dup and iIP4 cells, while increased MAPK signaling was found in iNP2_N771_H773dup. Increased cell migration and invasion were found in all cells carrying EGFR mutations when compared to iNP2 cells, and this effect was inhibited by either PI3K or MEK inhibitor. Notably, iNP2 cells expressing the N771_H773dup mutant showed the highest migration and invasion abilities. These results suggest that specific mutations in EGFR exon 20 play a crucial role in SIP development, partially though hyper-activation of the PI3K/AKT and MAPK signaling pathways. This study presents the first in vitro model for SIP development, which could facilitate further investigations into SIP pathogenesis and preclinical studies for new therapeutic agents.

Sinonasal Cancer: Improving Classification, Stratification and Therapeutic Options

The nasal cavities and paranasal sinuses are the site of origin of a wide spectrum of histologically and clinically distinct disease entities [...].

Frontal sinus carcinoma in forty-one dogs (2001-2022)

Reports on canine frontal sinus carcinomas (FSCs) are scarce. This retrospective review of 41 dogs with FSC (2001-2022) describes demographic and clinical characteristics of canine FSC and reports the clinical experience and overall survival following treatment with toceranib phosphate (TOC) and meloxicam in 10 cases. Median age at diagnosis was 10.6 years (range: 6.5-15.4 years). There was a male-to-female-ratio of 2.4:1. The most common breeds were Jack Russell Terriers (JRT) (n = 7; 17.1%) and Rottweilers (n = 3, 7.3%). Mesocephalic breeds (70.6%) were most commonly affected, brachycephalics accounted for 8.8%. The most frequent clinical signs included skull deformation dorsomedial to the eye (87.5%), pain/head-shyness (40.0%), ocular (22.5%)/nasal (17.5%) discharge, and exophthalmos (17.5%). Duration of symptoms prior to diagnosis varied from a few days to 9 months. There were no neurological signs at initial presentation despite imaging evidence of osteolysis of the lamina interna of the frontal bone in most dogs (69.4%). In 11.5%, pulmonary changes suggestive of metastasis or concurrent primary pulmonary neoplasia were present. Tumour types included squamous cell carcinoma (58.5%), unspecified carcinoma (29.3%), and adenocarcinoma (9.8%). Ten dogs were treated with TOC (median 2.8 mg/kg EOD or three times per week) and meloxicam (0.1 mg/kg, EOD) (TOC-M), resulting in subjective regression of skull deformity in 8/10 (80.0%) patients. Overall median survival time with TOC-M was 183.5 days (range: 120-434 days). FSCs typically present with skull deformation, but no overt neurological signs. Male dogs and JRT may be overrepresented. The use of TOC-M in FSC appears promising and warrants further prospective evaluation.

Molecular Basis and Rationale for the Use of Targeted Agents and Immunotherapy in Sinonasal Cancers

Despite the progress of surgery, radiotherapy, and neoadjuvant chemotherapy, the prognosis for advanced sinonasal cancers (SNCs) remains poor. In the era of precision medicine, more research has been conducted on the molecular pathways and recurrent mutations of SNCs, with the aim of understanding carcinogenesis, helping with diagnosis, identifying prognostic factors, and finding potentially targetable mutations. In the treatment of SNC, immunotherapy is rarely used, and no targeted therapies have been approved, partly because these tumors are usually excluded from major clinical trials. Data on the efficacy of targeted agents and immune checkpoint inhibitors are scarce. Despite those issues, a tumor-agnostic treatment approach based on targeted drugs against a detected genetic mutation is growing in several settings and cancer subtypes, and could also be proposed for SNCs. Our work aims to provide an overview of the main molecular pathways altered in the different epithelial subtypes of sinonasal and skull base tumors, focusing on the possible actionable mutations for which potential target therapies are already approved in other cancer types.

Recurrence rates of de-novo versus inverted papilloma-transformed sinonasal squamous cell carcinoma: a meta-analysis

Background: There is a paucity of reporting on recurrence patterns of de-novo sinonasal squamous cell carcinoma (DN-SCC) and inverted-papilloma-transformed sinonasal squamous cell carcinoma (IP-SCC). Method: A systematic literature review queried studies comparing recurrence patterns in patients with both DN-SCC and IP-SCC. Primary outcomes included local and regional recurrence and rates of distant metastasis. Of the 595 studies screened, eight were included. Results: Patients with DN-SCC had significantly higher rates of positive margins, advanced T classification (T3/T4), treatment with chemotherapy and radiotherapy. There were no significant differences in local recurrence or regional recurrence. Overall risk of distant metastasis was lower in IP-SCC. DN-SCC, compared to IP-SCC, is more likely to present with advanced TNM classification and have positive margins after surgical resection, which may affect rates of distant metastasis and recurrence. Conclusions: The findings in this study suggest IP-SCC may be a less aggressive malignancy compared to DN-SCC, with the possibility of a reduced role for adjuvant therapy in IP-SCC. Further studies are required to better understand differences in tumor biology and treatments strategies between IP-SCC and DN-SCC.