Lung Squamous Adenocarcinoma Research Articles

Integrative prognostic modeling for stage III lung adenosquamous carcinoma post-tumor resection: machine learning insights and web-based implementation.

The prognostic landscape of stage III Lung Adenosquamous Carcinoma (ASC) following primary tumor resection remains underexplored. A thoughtfully developed prognostic model has the potential to guide clinicians in patient counseling and the formulation of effective therapeutic strategies. Utilizing data from the Surveillance, Epidemiology, and End Results database spanning 2000 to 2018, this study identified independent prognostic factors influencing Overall Survival (OS) in ASC using Boruta analysis. Employing Gradient Boosting, Random Forest, and Neural Network algorithms, predictive models were constructed. Model performance was assessed through key metrics, including Area Under the Receiver Operating Characteristic Curve (AUC), calibration plot, Brier score, and Decision Curve Analysis (DCA). Among 241 eligible patients, seven clinical parameters-age, sex, primary tumor size, N stage, primary tumor site, chemotherapy, and systemic therapy-were identified as significant predictors of OS. Advanced age, male gender, larger tumor size, absence of chemotherapy, and lack of systemic therapy were associated with poorer survival. The Random Forest model outperformed others, achieving 3- and 5-year AUCs of 0.80/0.79 (training) and 0.74/0.65 (validation). It also demonstrated better calibration, lower Brier scores (training: 0.189/0.171; validation: 0.207/0.199), and more favorable DCA. SHAP values enhanced model interpretability by highlighting the impact of each parameter on survival predictions. To facilitate clinical application, the Random Forest model was deployed on a web-based server for accessible prognostic assessments. This study presents a robust machine learning model and a web-based tool that assist healthcare practitioners in personalized clinical decision-making and treatment optimization for ASC patients following primary tumor resection.

Wolf in sheep’s clothing: a case of primary lung adenosquamous carcinoma mimicking traumatic pulmonary pseudocyst

BackgroundTraumatic pulmonary pseudocyst is a rare “cystlike” lung lesion that typically develops following blunt chest trauma. It differs from lung cancer associated with cystic airspaces in terms of pathogenic mechanisms, clinical manifestations, and radiological features. Furthermore, there are few reports of the diagnostic bias between traumatic pulmonary pseudocyst and lung cancer associated with cystic airspaces. Here, we present a rare case of lung cancer associated with cystic airspaces that mimicks traumatic pulmonary pseudocyst.Case presentationA 61-year-old man with no chest medical or surgical history, no chest radiologic examination within the last five years, and no smoking history had an air-filled “cystlike” lesion surrounded by solid components and ground-glass opacities in the middle third of the right upper lobe of the lung during a computed tomography evaluation following blunt chest trauma. He was initially diagnosed with traumatic pulmonary pseudocyst and treated conservatively. On the third post-trauma day, he experienced hemoptysis, which was successfully treated with intravenous hemostatic medication. On the ninth post-trauma day, he exhibited a significant hemoptysis and a moderate dyspnea. A subsequent chest computed tomography scan demonstrated that the solid components had entered the lesion’s cavity and significantly expanded, and the surrounding ground-glass opacities had slightly enlarged. A contrast-enhanced chest computed tomography scan and a three-dimensional reconstruction computed tomography image confirmed that the solid components were a hematoma caused by damage to the right upper pulmonary vein. A right upper lobectomy was performed based on the concern about severe intrapulmonary bleeding. An intraoperative frozen section analysis showed significant bleeding in the lung parenchyma. Adenosquamous carcinoma was unexpectedly identified during the postoperative pathological examination of the resected specimen. A diagnosis of primary lung adenosquamous carcinoma was made. He was discharged on the seventh postoperative day and followed up for two years without any recurrence.ConclusionsThe potential of lung cancer associated with cystic airspaces should be considered for “cystlike” lung lesions discovered in elderly patients after blunt chest trauma. A comprehensive review of the medical history, meticulous analysis of the radiological findings, and close monitoring can help clinicians reduce the risk of diagnostic bias.

Ensartinib in the treatment of anaplastic lymphoma kinase-positive locally advanced or metastatic patients with lung squamous or adenosquamous carcinoma: A real-world, retrospective study.

To report the efficacy and safety of ensartinib, an anaplastic lymphoma kinase (ALK) inhibitor, in treating patients with ALK-positive advanced lung squamous cell carcinoma (LUSC) or lung adenosquamous carcinoma (LASC) in China. This retrospective study analyzed data for 36 advanced-stage patients with ALK-positive LUSC (cohort A) and 13 patients with ALK-positive LASC (cohort B) between December 16, 2020 and December 16, 2021. All patients received once-daily ensartinib 225mg. Outcome analysis included the demographic characteristics, tumor response, progression-free survival (PFS), and treatment-related adverse events (TRAE). Among the 49 patients, the majority were under 65 years old (73.5%), non-smokers (85.7%), had an Eastern Cooperative Oncology Group Performance Status of 0-1 (77.6%), and were at stage IV (71.4%). All patients were included in the efficacy and safety analysis. Seven PFS events were reported in cohort A while no patients experienced PFS events in cohort B. The median PFS was not estimable for both cohorts. In cohort A, the objective response rate (ORR) was 63.9%, and the disease control rate (DCR) was 83.3%. In the cohort B, the ORR was 76.9% and the DCR was 100.0%. Rash was the only TRAE reported in the cohort A (8.3%) and cohort B (23.1%). No patients had grade 3 or higher TRAE. Ensartinib has been tentatively proven favorable efficacy and tolerability in the treatment of patients with ALK-positive advanced LUSC or LASC in the real-world. However, confirmatory studies are still needed in larger sample sizes.

Multi-omics profiling the genomic origin and adeno-squamous transdifferentiation mechanism in adenosquamous carcinoma.

e20032 Background: Adenosquamous carcinoma (ASC) represents a rare subtype (0.4-4%) of non-small-cell lung cancer (NSCLC), with its multi-omic landscape yet to be fully elucidated. This study aims to explore the genomic origins and molecular mechanisms of adeno-squamous transdifferentiation in lung ASC through comprehensive multi-omics. Methods: We analyzed 69 samples from 31 lung ASC patients, including 16 FFPE samples with microdissected paired adenocarcinoma (AC) and squamous cell carcinoma (SCC) components, and additionally, incorporated pure Lung Adenocarcinoma (LUAD, n = 51) and pure Squamous Cell Carcinoma (LUSC, n = 28) for comparative analysis. Techniques included whole-exome sequencing, whole-genome methylation profiling, transcriptomics, single-cell RNA sequencing, and spatial transcriptomics. Results: AC and SCC exhibited similar genomic mutation landscapes, indicating a common genomic origin for AD and SCC. The SCC component in ASC displayed higher homologous recombination repair deficiency (HRD) and a notable 16p13.3 deletion in 31% of ASC transformations. Differential methylation analysis highlighted TP63's lower methylation in SCC, correlating negatively with RNA expression (P < 0.001), indicative of methylation-driven regulation. DMR binding motif analysis revealed hypo-methylation in p63, p53, and AP-1 motifs, and hyper-methylation in MKX2-1, FOXA1/2 motifs (P < 0.05). The transition from AC to SCC in ASC was marked by upregulated MYC signaling, proliferation, and DNA repair, with EMT changes not methylation-driven. Metabolic pathways were upregulated, and EMT/KRAS pathways downregulated in SCC compared to LUSC. Immune infiltration in LUAD-AC-ASC transformation showed an initial increase and subsequent decrease, transitioning from immune-infiltrated and immune-excluded to immune-desert phenotypes. IL36G of the IL1 family was highly expressed in the SCC component and strongly correlated with the squamous marker P63 (Pearson r = 0.72, P < 0.001). Single-cell RNA-seq data demonstrated a significant increase in IL36G in squamous cells of lung ASC. In vivo models showed adeno-squamous differentiation in adenocarcinoma cells expressing IL36G. Conclusions: This study provides a comprehensive multi-omic insight into the complex genomic and epigenomic landscape of ASC, highlighting a shared genomic origin and distinct molecular mechanisms in the adeno-squamous transdifferentiation process. The findings, particularly the role of TP63 methylation and IL36G expression in the SCC component, offer novel insights into the molecular heterogeneity of ASC. These results not only deepen our understanding of ASC but also pave the way for future investigations into targeted therapies that could potentially exploit these molecular distinctions for more effective treatment strategies in ASC.

Evaluation of the genomic and immune profiles of patients with lung adenosquamous carcinoma (LUAS) and association of response to treatment.

8567 Background: LUAS is a rare subset of non-small cell lung cancer (NSCLC) comprising up to 4% of cases, characterized by at least 10% of both adenocarcinoma and squamous components. Limited studies exist on LUAS regarding the genomic/immune landscape and response to immunotherapy (IO). Methods: NSCLC samples (n = 35404) underwent NextGen Sequencing of DNA (592 genes or whole exome)/RNA (whole transcriptome) at Caris Life Sciences. PD-L1 expression was assessed using IHC (22c3; positive: TPS >1%). High tumor mutational burden (TMB-H) was defined as ≥10 mut/MB. Cell infiltration in the tumor microenvironment was estimated by quanTIseq. Gene expression profiles were analyzed for transcriptomic signatures (IFN-γ) predictive of IO response. Real-world overall survival (rwOS) was obtained from insurance claims data, calculated from time of biopsy to last contact. Time on treatment (TOT) was calculated from the first pembrolizumab (pembro) treatment to the last. Mann-Whitney U and X2/Fisher-Exact tests were applied where appropriate, with p-values adjusted ( p < .05). Results: Among NSCLC samples, 1.0% (n=374) were LUAS, 26.5% (n = 9365) were squamous (SCC) and 72.5% (n = 25665) were adenocarcinoma (AC). LUAS exhibited actionable alterations in 29% (n = 110/374) of cases, with MET exon 14 skipping alteration ( METex14) significantly higher in LUAS compared to SCC or AC (9.02% vs 1.21% vs 2.61%, p < 0.01). BRAF V600E (0.54% vs 0.13%, p = 0.041) and ALK-Fusion (1.13% vs 0.12%, p = 0.0145) were higher in LUAS compared to SCC, while PIK3CA mutation was higher in LUAS compared to AC (10.8% vs 4.1%, p <0.01). Notably, LUAS exhibited higher prevalence of KRAS, targetable EGFRand STK11 mutations compared to SCC but lower compared to AC ( KRAS G12C: 8.63% vs 1.37% vs 13.24%, p <0.01; EGFR: 13.1% vs 1.12% vs 17.53%, p<0.01; STK11: 6.97% vs 1.83% vs 17.22%, p<0.01). LUAS exhibited significantly higher PD-L1+ (65.5% vs 59.8% vs 53.7%, p <0.01), along with elevated expression of immune checkpoint genes and the IFN-γ signature compared to AC and SCC. Moreover, LUAS exhibited significantly higher neutrophils, CD8 T cells, M2 macrophages and Tregs compared to SCC. LUAS showed improved rwOS compared to SCC (HR 0.792, p<0.01), with no difference noted in the rwOS between LUAS and AC (HR = 0.98, p = 0.81). While PD-L1+ was not associated with TOT on pembro in LUAS, high TMB showed improved TOT on pembro in LUAS. Conclusions: This study provides a comprehensive genomic landscape of LUAS, highlighting actionable alterations in ~ 29% of cases. LUAS exhibits distinct molecular and clinical features compared to AC and SCC, with enrichment in actionable METex14, emphasizing the need for NGS testing. Although PD-L1 status may not significantly impact TOT in LUAS, it remains relevant in other NSCLC subtypes on IO and high TMB emerges as a potential biomarker for favorable TOT on pembro in LUAS, warranting further investigation.

Metastatic pattern and prognosis in patients with lung adenosquamous carcinoma: A surveillance, epidemiology, and end results-based population study

BackgroundLung adenosquamous carcinoma (ASC) is a rare tumor with high invasive and metastatic potential. Few studies have explored metastatic patterns in patients with advanced-stage ASC. MethodsPatients diagnosed with ASC in the Surveillance, Epidemiology, and End Results database from 2010 to 2015 were selected. Descriptive statistics were obtained to characterize the metastatic sites of the study participants. The Kaplan–Meier method was applied to compare survival curves among patients with different metastatic patterns. Cox regression analysis was performed to evaluate risk factors for metastasis. ResultsA total of 858 eligible patients with ASC were enrolled; the mean age was 71.5 years (standard deviation ± 7.8 years). There was a slightly higher proportion of male patients (54.0 %). A total of 63.2 % of patients harbored single-site metastasis (median OS: 5 months), 23.6 % of patients had two-site metastasis (median OS: 4 months), and approximately 10 % of patients harbored three or more sites metastasis (median OS: 3 months). Bone (56.9 %) was the most frequent site of metastasis (median OS: 4 months), followed by lung metastasis (37.6 %, median OS: 5 months), liver metastasis (22.1 %, median OS: 5 months), and brain metastasis (21.4 %, median OS: 4 months). Chemotherapy decreased the risk of death by 70 % (HR = 0.296, 95 % CI 0.241–0.363), 70 % (HR = 0.302, 95 % CI 0.224–0.406), 78 % (HR = 0.218, 95 % CI 0.151–0.314), and 70 % (HR = 0.302, 95 % CI 0.231–0.396) in patients harboring bone, liver, brain and lung metastases, respectively. The brain increased the risk of death by 50 % (HR = 1.501, 95 % CI 1.209–1.865), 64 % (HR = 1.644, 95 % CI 1.126–2.402), and 128 % (HR = 2.284, 95 % CI 1.653–3.157) in patients harboring bone, liver and lung metastases, respectively. ConclusionPatients with advanced-stage ASC have unfavorable outcomes. Early detection and aggressive treatment can improve patients outcomes.

Clinicopathological Features and Survival Outcomes of Resected Lung Adenosquamous Carcinoma: Results From a Nationwide Japanese Registry Data

ObjectivesThe objective of this study was to clarify the clinicopathological features and prognostic factors of resected lung adenosquamous carcinoma (ASC) using a nationwide multi-institutional database. MethodsWe retrospectively reviewed the records of 15,542 patients who underwent complete R0 resection for ASC (n = 326), adenocarcinoma (AC, n = 11,820), or squamous cell carcinoma (SC, n = 3396) from a Japanese lung cancer registry in 2010. To reduce the selection bias, an inverse probability of treatment weighting (IPTW) method using a propensity score was implemented. ResultsThe ASC group showed worse recurrence-free and overall survival (RFS and OS) than both the AC and SC groups (5-year OS: 57.5% in ASC, 83.9% in AC [< 0.001], and 62.3% in SC [P = .086]). In multivariate analyses, prognostic factors that affected OS for ASC included male, p-stage II-III, and postoperative complications within 30 days (grade ≥ 3 in the Clavien–Dindo classification). The sensitizing EGFR mutation was detected in 28 (21.5%) of 130 screened patients with ASC, but it did not affect either RFS, OS, or postrecurrence survival. Although more patients in the ASC group received adjuvant chemotherapy compared to the AC and SC groups, both multivariate and IPTW-adjusted analyses did not show positive impact of adjuvant chemotherapy on RFS and OS in ASC. ConclusionsIn this nationwide registry study, lung ASC was more aggressive than both AC and SC. No apparent survival impact of conventional adjuvant chemotherapy prompted us to investigate novel adjuvant strategies to optimize survival outcomes.

Clinicopathological Characteristics and Prognosis Analysis of Lung Carcinoma With p40/TTF1 Coexpression and Lung Adenosquamous Carcinoma: Lung Carcinoma With p40/TTF1 Coexpression Is a Rare Tumor With High Metastatic Potential.

Background. Lung carcinoma with p40/TTF1 coexpression (LC-PTC) is a very rare tumor with poor prognosis, and few cases have been reported to date. Objectives. To better understand biological behavior and prognosis of LC-PTC. Methods. We collected 9 examples of LC-PTC and compared them with 36 lung adenosquamous carcinomas during the same period in clinicopathologic characteristics, biologic behaviour, and prognosis. Results. Lung carcinoma with p40/TTF1 coexpression mainly occurred in middle-aged and elderly men; 8 tumors belonged to the peripheral type, and 1 belonged to the central type. The rates of lymph node and distant metastasis were 88% (7/8) and 50% (4/8), respectively; 2 patients died during follow-up. Histologically, the LC-PTC showed nest-like growth pattern without glandular growth pattern; the surface of 2 tumors was covered with ciliated columnar epithelium and tumor cells grew under the columnar epithelium. In all patients, tumor cells diffusely coexpressed p40 and TTF1. Although there was no significant difference in the maximum diameter of tumor with lymph node metastasis or with distant metastasis between LC-PTC and lung adenosquamous carcinoma, LC-PTC had a higher rate of lymph node metastasis and distant metastasis. There was no significant difference in overall survival of patients between LC-PTC and lung adenosquamous carcinoma. Additional histologic evaluation of normal pulmonary structures revealed that p40/TTF1 coexpression cells existed in bronchial mucosa and the number of cells coexpressing p40/TTF1 increased gradually from proximal bronchus to distal bronchus. Conclusions. Lung carcinoma with p40/TTF1 coexpression is a rare tumor with high metastatic potential and may originate from p40/TTF1 coexpression cells in distal bronchial mucosa.

EML4-ALK fusions drive lung adeno-to-squamous transition through JAK-STAT activation.

Human lung adenosquamous cell carcinoma (LUAS), containing both adenomatous and squamous pathologies, exhibits strong cancer plasticity. We find that ALK rearrangement is detectable in 5.1-7.5% of human LUAS, and transgenic expression of EML4-ALK drives lung adenocarcinoma (LUAD) formation initially and squamous transition at late stage. We identify club cells as the main cell-of-origin for squamous transition. Through recapitulating lineage transition in organoid system, we identify JAK-STAT signaling, activated by EML4-ALK phase separation, significantly promotes squamous transition. Integrative study with scRNA-seq and immunostaining identify a plastic cell subpopulation in ALK-rearranged human LUAD showing squamous biomarker expression. Moreover, those relapsed ALK-rearranged LUAD show notable upregulation of squamous biomarkers. Consistently, mouse squamous tumors or LUAD with squamous signature display certain resistance to ALK inhibitor, which can be overcome by combined JAK1/2 inhibitor treatment. This study uncovers strong plasticity of ALK-rearranged tumors in orchestrating phenotypic transition and drug resistance and proposes a potentially effective therapeutic strategy.

Distant organ metastasis patterns and prognosis of lung adenosquamous carcinoma: a SEER database analysis.

Our purpose is to evaluate the patterns of organ metastasis and the prognosis in lung adenosquamous carcinoma patients with organ metastasis. We collected the data from the surveillance epidemiology and end results database, covering the period of 2000-2018. Cox regression, Kaplan-Meier and log-rank analyses were performed. Totally, 2698 patients were enrolled, comprising 851 (31.54%) patients diagnosed with organ metastasis and 2017 (68.46%) patients without organ metastasis. Patients with distant organ metastasis show a significant decrease in median overall survival. In addition to the aforementioned factors, age over 70 years, male, main bronchus, advanced T stage, larger tumour size, absence of primary tumour surgery and lack of radiotherapy have all been identified as prognostic indicators associated with a poorer outcome. In terms of treatment options, patients with organ metastasis can benefit from chemotherapy and primary tumour surgery. Moreover, in patients with organ metastasis, those who received a combination treatment of surgery, chemotherapy and radiotherapy displayed the most favourable prognosis, with a median overall survival of 17 months. We identified the prognostic indicators for organ metastasis in patients with lung adenosquamous carcinoma. Highly selected patients who undergo a combination treatment of surgery, chemotherapy and radiotherapy may experience the greatest survival benefit.

Efficacy of epidermal growth factor receptor-tyrosine kinase inhibitor for lung adenosquamous cell carcinoma harboring EGFR mutation: a retrospective study and pooled analysis.

To explore the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) on lung adenosquamous cell carcinoma (ASC) with EGFR mutation. Efficacy of EGFR-TKIs in the treatment of advanced or recurrent lung ASC with EGFR mutations was assessed retrospectively in 44 patients. Pooled analysis of 74 patients using EGFR-TKIs, including 30 patients selected from 11 publications, was conducted. In our retrospective research, patients treated with EGFR-TKI in ASC with EGFR mutations had objective response rate (ORR) of 54.5%, disease control rate (DCR) of 79.5%, median progression free survival (mPFS) of 8.8 months, and median overall survival (mOS) of 19.43 months, respectively. A pooled analysis reveals ORR, DCR, mPFS, and mOS are, respectively, 63.4%, 85.9%, 10.00 months, and 21.37 months for ASC patients. In patients with deletions in exon 19 and exon 21 L858R mutations, mPFS (11.0 versus 10.0 months, P=0.771) and mOS (23.67 versus 20.33 months, P=0.973) were similar. Erlotinib or gefitinib-treated patients had an overall survival trend that was superior to that of icotinib-treated patients. ASC harboring EGFR mutations can be treated with EGFR-TKI in a similar manner to Adenocarcinoma (ADC) harboring EGFR mutations. There is still a need for further investigation to identify the separate roles of ASC's two components in treating EGFR.

Current status and prospect of PET-related imaging radiomics in lung cancer.

Lung cancer is highly aggressive, which has a high mortality rate. Major types encompass lung adenocarcinoma, lung squamous cell carcinoma, lung adenosquamous carcinoma, small cell carcinoma, and large cell carcinoma. Lung adenocarcinoma and lung squamous cell carcinoma together account for more than 80% of cases. Diverse subtypes demand distinct treatment approaches. The application of precision medicine necessitates prompt and accurate evaluation of treatment effectiveness, contributing to the improvement of treatment strategies and outcomes. Medical imaging is crucial in the diagnosis and management of lung cancer, with techniques such as fluoroscopy, computed radiography (CR), digital radiography (DR), computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET)/CT, and PET/MRI being essential tools. The surge of radiomics in recent times offers fresh promise for cancer diagnosis and treatment. In particular, PET/CT and PET/MRI radiomics, extensively studied in lung cancer research, have made advancements in diagnosing the disease, evaluating metastasis, predicting molecular subtypes, and forecasting patient prognosis. While conventional imaging methods continue to play a primary role in diagnosis and assessment, PET/CT and PET/MRI radiomics simultaneously provide detailed morphological and functional information. This has significant clinical potential value, offering advantages for lung cancer diagnosis and treatment. Hence, this manuscript provides a review of the latest developments in PET-related radiomics for lung cancer.

Correlation analysis of hemoglobin, albumin, lymphocyte, platelet score and platelet to albumin ratio and prognosis in patients with lung adenosquamous carcinoma.

To investigate the effect of hemoglobin, albumin, lymphocytes, platelet (HALP) score and platelet to albumin ratio (PAR) on prognosis of patients with lung adenosquamous carcinoma (ASC) after surgery. A total of 52 patients diagnosed with ASC after surgical resection were collected from Nanjing Chest Hospital from 2012 to 2021, and their general clinical data, pathological data and laboratory indexes were collected. The changes of Alb and Plt levels before and after surgery, HALP scores (hemoglobin albumin lymphocytes/platelets), and postoperative PAR, PLR, NLR were retrospectively analyzed, and their influence on the prognosis of patients with ASC was investigated. The cut-off value of △Alb, △Plt, postoperative PAR, PLR and NLR were determined by the receiver operating characteristic (ROC) curve, the optimal cut-off value of HALP score before and after surgery was calculated by using X-tile software, and the clinicopathological characteristics were compared between the high PAR and low PAR groups and between high HALP score and low HALP score group to analyze the factors influencing the prognosis of patients with ASC. Univariate and multivariate Cox proportional regression analyses were used to assess independent risk factors affecting overall survival (OS) and disease-free survival (DFS) in patients with ASC. Kaplan-Meier method was used to evaluate the correlation between OS, DFS and PAR and HALP score. A critical value of PAR was 7.40×10^9 and an area under the curve (AUC) of 0.737 (95%CI: 0.597-0.876, P = 0.004). The best cut-off value of the preoperative HALP score was 24.3. Univariate Cox analysis showed that the cut margin (P = 0.013), the degree of differentiation (P = 0.021), N stage (P = 0.049), △Plt (P = 0.010), △Alb (P = 0.016), PAR (P = 0.003), NLR (P = 0.025), PLR (P = 0.029), preoperative HALP score (P = 0.000) and post-operative HALP score (P = 0.010) were all associated with postoperative OS in ASC patients. Cut margin (P = 0.029), the degree of differentiation (P = 0.045), maximum tumor diameter (P = 0.018), N stage (P = 0.035), △Plt (P = 0.007), △Alb (P = 0.007), PAR (P = 0.004), NLR (P = 0.041), PLR (P = 0.030), preoperative HALP score (P = 0.000), and postoperative HALP score (P = 0.011) were related to postoperative DFS in ASC patients. Multivariate analysis revealed that PAR (HR: 6.877, 95%CI: 1.817-26.038, P = 0.005), differentiation degree (HR: 0.059, 95%CI: 0.006-0.591, P = 0.016) and preoperative HALP score (HR: 0.224, 95%CI: 0.068-0.733, P = 0.013) had significant effect on OS. Tumor maximum diameter (HR: 3.442, 95%CI: 1.148-10.318, P = 0.027) and preoperative HALP score (HR: 0.268, 95%CI: 0.085-0.847, P = 0.025) had significant influence on DFS. PAR and preoperative HALP score were potentially useful biomarkers for evaluating the outcome of patients with postoperative ASC. PAR, the degree of differentiation and preoperative HALP score were independent prognostic factors for postoperative OS in ASC patients. Maximum tumor diameter and preoperative HALP score were independent prognostic factors for postoperative DFS in ASC patients.

Clonal dynamics and Stereo-seq resolve origin and phenotypic plasticity of adenosquamous carcinoma

The genomic origin and development of the biphasic lung adenosquamous carcinoma (ASC) remain inconclusive. Here, we derived potential evolutionary trajectory of ASC through whole-exome sequencing, Stereo-seq, and patient-derived xenografts. We showed that EGFR and MET activating mutations were the main drivers in ASCs. Phylogenetically, these drivers and passenger mutations found in both components were trunk clonal events, confirming monoclonal origination. Comparison of multiple lesions also revealed closer genomic distance between lymph node metastases and the ASC component with the same phenotype. However, as mutational signatures of EGFR-positive lung squamous carcinomas (LUSCs) were more comparable to EGFR-positive ASCs than to wild-type LUSCs, we postulated different origination of these LUSCs, with ASC being the potential intermediate state of driver-positive LUSCs. Spatial transcriptomic profiling inferred transformation from adenocarcinoma to squamous cell carcinoma, which was then histologically captured in vivo. Together, our results explained the development of ASC and provided insights into future clinical decisions.

Radiomics and deep learning models to differentiate lung adenosquamous carcinoma: A multicenter trial

Adenosquamous carcinoma (ASC) is frequently misdiagnosed or overlooked in clinical practice due to its dual histological components and potential transformation from either adenocarcinoma (ADC) or squamous cell carcinoma (SCC). Our study aimed to differentiate ASC from ADC and SCC by incorporating features of enhanced CTs and clinical characteristics to build radiomics and deep learning models. The classification models were trained in Xiangya Hospital and validated in two other independent hospitals. The areas under the receiver operating characteristic curves (AUC), accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were used to estimate the performance. The optimal three-class classification model achieved a maximum AUC of 0.89 and accuracy of 0.81 in external validation sets, AUC of 0.99 and accuracy of 0.99 in the internal test set. These findings highlight the efficacy of our models in differentiating ASC, providing a non-invasive, timely, and accurate diagnostic approach before and during the treatment.

Pulmonary venous extension of adenosquamous lung carcinoma into the left atrium with resultant mitral valve obstruction.

Pulmonary venous extension of adenosquamous lung carcinoma into the left atrium with resultant mitral valve obstruction.

Abstract 107: EML4-ALK fusions drive lung adeno-to-squamous transdifferentiation through phase separation-mediated JAK-STAT activation

Abstract Phenotypic plasticity is now recognized as a hallmark of cancer. EML4-ALK is the most common oncogenic fusion in non-small-cell lung cancer (NSCLC), accounting for approximately 5% of NSCLC patients. Different from other oncogenic drivers, e.g., EGFR or KRAS mutants, the ALK-rearranged tumors often show strong phenotypic plasticity and unique clinicopathologic features. Previous studies show that certain ALK-rearranged LUAD express the squamous biomarker p63 besides the adenomatous biomarker TTF1. Several studies also show that ALK-rearrangement is observed in certain lung tumors with mixed adenosquamous pathology, and quite rare in LUSC. Moreover, histological transformation such as adeno-to-squamous transdifferentiation (AST) are also observed in the relapsed ALK-rearranged LUAD patients failed from molecular targeted therapy. These clinical observations implicate a potential link between the oncogenic ALK fusions, and cancer plasticity, and even drug resistance. We established two lung cancer mouse models with wildtype EML4-ALK or L1196M mutant. H&amp;E and IHC staining were conducted to pathologically define the LUAD and lung squamous carcinoma (LUSC). Single-cell RNA sequencing (scRNA-Seq) of mouse LUAD, LUSC and human ALK-rearranged LUAD were conducted to uncover the intratumorally heterogeneity and identify the cell subpopulations with squamous signature. Organoid culture system was established for AST process recapitulation and mechanism studies. Drug treatment in vitro and in vivo were conducted to study the TKI responses of LUAD and LUSC samples. Through analyses of RNA-seq and paired WGS data from 93 lung adenosquamous carcinoma specimens, we identified ALK-rearrangements were detectable at 7.5%. We then employ the EML4-ALK GEMM and find that transgenic expression of EML4-ALK fusion drives LUAD formation initially and squamous transformation at late stage, which mirrors the AST process in human ALK-rearranged lung adenosquamous carcinoma. We identify club cells as the main cell-of-origin for squamous transformation. Through recapitulating such lineage transition in organoids system, we identify the JAK-STAT signaling, activated by EML4-ALK phase separation, significantly promotes squamous transformation. Integrative study with scRNA-seq and immunostaining identify a plastic cell subpopulation in ALK-rearranged human LUAD showing squamous biomarker expression. Moreover, those also relapsed ALK-rearranged LUAD show notable upregulation of squamous biomarkers. Consistently, mouse squamous tumors or LUAD with squamous signature display certain resistance to ALK inhibitor, which can be overcome by combined JAK1/2 inhibitor treatment. Our study not only uncovers the link between EML4-ALK fusions and cancer plasticity as well as TKI resistance, but also provides a potentially effective therapeutic strategy. &amp;lt;!–EndFragment–&amp;gt; Citation Format: Zhen Qin, Hongbin Ji. EML4-ALK fusions drive lung adeno-to-squamous transdifferentiation through phase separation-mediated JAK-STAT activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 107.

Counteracting lineage-specific transcription factor network finely tunes lung adeno-to-squamous transdifferentiation through remodeling tumor immune microenvironment.

Human lung adenosquamous cell carcinoma (LUAS), containing both adenomatous and squamous pathologies, harbors strong plasticity and is significantly associated with poor prognosis. We established an up-to-date comprehensive genomic and transcriptomic landscape of LUAS in 109 Chinese specimens and demonstrated LUAS development via adeno-to-squamous transdifferentiation. Unsupervised transcriptomic clustering and dynamic network biomarker analysis identified an inflammatory subtype as the critical transition stage during LUAS development. Dynamic dysregulation of the counteracting lineage-specific transcription factors (TFs), containing adenomatous TFs NKX2-1 and FOXA2, and squamous TFs TP63 and SOX2, finely tuned the lineage transition via promoting CXCL3/5-mediated neutrophil infiltration. Genomic clustering identified the most malignant subtype featured with STK11-inactivation, and targeting LSD1 through genetic deletion or pharmacological inhibition almost eradicated STK11-deficient lung tumors. These data collectively uncover the comprehensive molecular landscape, oncogenic driver spectrum and therapeutic vulnerability of Chinese LUAS.

Clinical outcomes of immune checkpoint inhibitor therapy for advanced lung adenosquamous carcinoma.

Primary adenosquamous carcinoma (ASC) of the lung is a rare and aggressive disease and limited information is available on the efficacy of immune checkpoint inhibitors (ICIs) for this disease. Here, we evaluated the expression status of programmed death-1 ligand 1 (PD-L1) and efficacy of ICIs in patients with pulmonary ASC. The efficacy and toxicity of ICIs were examined in 38 patients with previously treated lung ASC from November 2017 to October 2021 in Zhejiang Cancer Hospital (Hangzhou, China). Survival curves were plotted using the Kaplan-Meier method and the Cox proportional hazards model applied for univariate and multivariate analyses. A total of 38 patients with ASC were included in this retrospective study. ICI treatment induced an objective response rate (ORR) of 23.7% and a disease control rate (DCR) of 86.8%. The median progression-free survival (PFS) and median overall survival (OS) were 5.47 and 24.10 months, respectively. Seventeen patients were successfully evaluated for PD-L1 expression status, with 11 (64.7%) identified as PD-L1-positive. ORR and DCR for PD-L1-positive patients were 36.4% (4/11) and 100% (11/11) and the corresponding values for PD-L1-negative patients were 0 (0/6) and 50% (3/6), respectively. The median PFS of PD-L1-positive and PD-L1-negative patient groups was 5.00 and 1.90 months (P=0.166) while the median OS was 11.30 months and not reached, respectively (P=0.966). The incidence rate of immune-related adverse events (irAEs) was 52.6%, with 13.2% grade 3-4 irAEs. The most common irAEs were malaise and pneumonitis. One patient died of pneumonitis during the study. ICIs show considerable potential as a treatment option for lung ASC. PFS and OS rates are similar for PD-L1-positive and PD-L1-negative patients. Further large-scale studies are required to establish the relationship between PD-L1 expression and response to ICIs in ASC.

Oxidative stress-triggered Wnt signaling perturbation characterizes the tipping point of lung adeno-to-squamous transdifferentiation

Lkb1 deficiency confers the Kras-mutant lung cancer with strong plasticity and the potential for adeno-to-squamous transdifferentiation (AST). However, it remains largely unknown how Lkb1 deficiency dynamically regulates AST. Using the classical AST mouse model (KrasLSL-G12D/+;Lkb1flox/flox, KL), we here comprehensively analyze the temporal transcriptomic dynamics of lung tumors at different stages by dynamic network biomarker (DNB) and identify the tipping point at which the Wnt signaling is abruptly suppressed by the excessive accumulation of reactive oxygen species (ROS) through its downstream effector FOXO3A. Bidirectional genetic perturbation of the Wnt pathway using two different Ctnnb1 conditional knockout mouse strains confirms its essential role in the negative regulation of AST. Importantly, pharmacological activation of the Wnt pathway before but not after the tipping point inhibits squamous transdifferentiation, highlighting the irreversibility of AST after crossing the tipping point. Through comparative transcriptomic analyses of mouse and human tumors, we find that the lineage-specific transcription factors (TFs) of adenocarcinoma and squamous cell carcinoma form a “Yin-Yang” counteracting network. Interestingly, inactivation of the Wnt pathway preferentially suppresses the adenomatous lineage TF network and thus disrupts the “Yin-Yang” homeostasis to lean towards the squamous lineage, whereas ectopic expression of NKX2-1, an adenomatous lineage TF, significantly dampens such phenotypic transition accelerated by the Wnt pathway inactivation. The negative correlation between the Wnt pathway and AST is further observed in a large cohort of human lung adenosquamous carcinoma. Collectively, our study identifies the tipping point of AST and highlights an essential role of the ROS-Wnt axis in dynamically orchestrating the homeostasis between adeno- and squamous-specific TF networks at the AST tipping point.