Histologic Changes in Non-Small Cell Lung Cancer Under Various Treatments: A Comparison of Histology and Mutation Status in Serial Samples

Clinical application of microwave ablation combined with coaxial needle biopsy using different sequences for treating lung nodules suggestive of malignancy

OBJECTIVE

This study aimed to evaluate the safety and efficacy of computed tomography (CT)-guided percutaneous microwave ablation (MWA) combined with coaxial needle biopsy performed in different sequences for treating lung nodules with signs of malignancy.

METHODS

A retrospective analysis was conducted on 51 patients (56 lesions) with lung nodules treated with MWA and coaxial needle biopsy between January 2020 and March 2024. Patients were divided into Group A (post-MWA biopsy; 26 patients, 29 lesions) and Group B (pre-MWA biopsy; 25 patients, 27 lesions). Ablation parameters, postoperative complications, prognosis, and pathological diagnosis rates were compared between groups. Patients with malignant pathology findings from both groups (Group C) were analyzed for overall survival (OS) and progression-free survival (PFS).

RESULTS

Technical success for needle biopsy and MWA was 100%. Pneumothorax incidence was 24.14% (7/29) in Group A and 33.33% (9/27) in Group B (p = 0.447). Intrapulmonary hemorrhage occurred in 13.79% (4/29) of Group A patients and 37.04% (10/27) of Group B of patients, showing a significantly higher rate in Group B (p = 0.026). The pathological diagnosis rate was 100% in both the groups, with malignancy rates of 72.41% (21/29) in Group A and 81.48% (22/27) in Group B (p = 0.422). For Group C, the 1-3-year OS rates were 100.00%, 93.75%, and 75.00%, respectively, and the corresponding PFS rates were 97.50%, 84.38%, and 60.00%.

CONCLUSIONS

Biopsy post-MWA maintains pathological diagnostic accuracy while significantly reducing the incidence of intrapulmonary hemorrhage compared to pre-MWA biopsy.

Clinicopathologic features of histologic transformation in lung adenocarcinoma after treatment with epidermal growth factor receptor-tyrosine kinase inhibitors

BACKGROUND

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) may lead to drug resistance, and the underlying mechanism may involve histologic transformations to small cell carcinoma (SCC), squamous cell carcinoma (SqCC), and sarcomatoid carcinoma (SC). Although there are reports regarding these transformations, comprehensive analyses are limited.

METHODS

A total of 233 patients with primary lung adenocarcinoma treated with EGFR-TKIs were reviewed. Among them, 26 patients (11.1 %) showed histologic transformation.

RESULTS

Eleven patients (42.3 %) showed SCC and SqCC transformations respectively, and four patients (15.4 %) showed SC transformation. The median time from TKI initiation to transformation was 19.8 months (6.8-51.4) for SCC, 45.3 months (2.4-101.5) for SqCC, and 11.8 months (6.8-15.7) for SC. The median overall survival (OS) was 41.8 months (12.5-78.9), 72.6 months (18.8-112.7), and 23.7 months (17.4-34.4), respectively. The survival from transformation was 12.3 months (2.1-28.3), 16.9 months (0.7-43.2), and 11.4 months (1.6-23.5), respectively. The most common mutations were TP53, PTEN, and RB1 in SCC; TP53 and RB1 in SqCC; and TP53 and KMT2D in SC. SC transformation had the worst OS, followed by SCC and SqCC (p < 0.001). This prognosis difference was also reflected in the time to transformation after EGFR-TKI treatment (p = 0.005). However, survival after transformation was not associated with tumor subtypes (p = 0.536).

CONCLUSIONS

The analysis of mutation profiles and survival outcomes revealed that the transformation subtype affects prognosis. Additionally, the time taken to undergo transformation is critical for patient outcomes.

Whole Exome Sequencing Study Identifies Distinct Characteristics of Transformed Small Cell Lung Cancer With EGFR Mutation Compared to De Novo Small Cell and Primary Non-Small Cell Lung Cancers

BACKGROUND

Epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma (LUAD) is the most common subtype among non-small cell lung cancer (NSCLC) and targeted therapies are the primary approach for treatment. However, the development of resistance to therapy and histological transformation into small cell lung cancer (SCLC) present significant challenges. Understanding the mechanisms underlying this transformation is crucial for effective differential diagnosis and the formulation of treatment strategies.

METHODS

In this study, we collected tissue from 5 primary LUAD before SCLC transformation, 12 transformed SCLC after EGFR tyrosine kinase inhibitor (TKI) treatment, and 18 de novo SCLC from lung cancer patients treated at Beijing Chest Hospital, Capital Medical University from January 2015 to December 2021. Whole-exome sequencing was performed on these samples to compare the genomic alterations of these three tumor types, elucidating their similarities, differences, and connections. Statistical analyses were conducted using the Fisher exact test and performed with R v4.2.1 environment.

RESULTS

Among 12 transformed SCLC cases, the majority were female (10/12, 83.3%), non-smokers (10/12, 83.3%) and harbored EGFR 19del mutations (11/12, 91.7%). Four were with limited stage and 8 with extensive stage. TP53 mutations and RB1 loss are important but not necessary for SCLC transformation. The mutation rates of TP53 were 60% (3/5) in primary LUAD, 70% (7/10) in transformed SCLC, and 89% (16/18) in de novo SCLC. RB1 loss rates were 40% (2/5) in primary LUAD, 30% (3/10) in transformed SCLC, and 50% (9/18) in de novo SCLC. Additionally, mutations in COL22A1 and ALMS1 were only observed in transformed SCLC and de novo SCLC. In contrast, mutations in PTCH2, CNGB3, SPTBN5, CROCC, and MYO15A were more common in transformed SCLC, whereas PABPC3 and MUC19 mutations were more frequent in de novo SCLC. Smoking-related mutations (SBS4) were only found in de novo SCLC, with no changes observed in transformed SCLC. TMB levels were significantly lower in transformed SCLC compared to de novo SCLC (p = 0.01). Genomic instability was significantly higher in transformed SCLC compared to primary LUAD and de novo SCLC. This was supported by higher levels of homologous recombination deficiency (HRD, p = 0.025), uniparental disomy (UPD, p = 0.003), loss of heterozygosity (LOH, p = 0.008), and telomeric allelic imbalance (TAI, p = 0.02). The increased frequency of UPD events in transformed SCLC suggests that UPD may act as a "second hit" in Knudson's model, leading to biallelic inactivation of tumor suppressor genes. High similarity was observed in genetic alterations related to DNA damage repair (DDR) and Notch signaling pathways between transformed SCLC and de novo SCLC.

CONCLUSIONS

The identification of these specific genomic alterations in transformed SCLC contributes to a better understanding of the mechanisms driving this transformation. This knowledge may guide future predicting the transformation of SCLC and the development of personalized treatment strategies for these patients.

Metachronous development of L858R and T790M EGFR mutations following ALK inhibitor therapy in stage IV lung adenocarcinoma: a case report

Background

Metachronous lung cancers with distinct driver mutations are rare, particularly following targeted therapy. This report presents a unique case of tumor evolution in non-small cell lung cancer (NSCLC).

Case Description

A 73-year-old East Asian woman was diagnosed with stage IV anaplastic lymphoma kinase (ALK)-rearranged lung adenocarcinoma in the right middle lobe (RML). After 18 months of alectinib treatment, while the initial lesion regressed, a new nodule developed in the right upper lobe (RUL). Biopsy revealed adenocarcinoma with epidermal growth factor receptor (EGFR) L858R/T790M co-mutations without ALK rearrangement. We conducted a comparative analysis of genetic alterations in biopsies from 2022 and 2024 using targeted next-generation sequencing (NGS), revealing significant molecular evolution over time, with a marked increase in single nucleotide variants (SNVs) and copy number variants (CNVs) and distinct changes in key mutations such as ALK-EML4 and EGFR. The patient received stereotactic body radiotherapy (SBRT) for the new lesion while continuing alectinib, resulting in significant improvement until now.

Conclusions

This case represents the first documented occurrence of metachronous L858R and T790M EGFR mutations following ALK inhibitor therapy, highlighting the emergence of distinct driver mutations over time and reflecting temporal and spatial tumor heterogeneity. These findings underscore the importance of monitoring clonal evolution to guide tailored therapeutic strategies in NSCLC. Furthermore, re-biopsy is essential to assess tumor heterogeneity, identify potential drug resistance, and detect new mutations, ensuring that treatment strategies remain optimized for evolving disease conditions.

Patients outcomes in lung adenocarcinoma transforming to small-cell lung cancer after tyrosine kinase inhibitor therapy

BACKGROUND

Non-small cell lung cancer (NSCLC) transforming to small cell lung cancer (SCLC) is one of the mechanisms of resistance to tyrosine kinase inhibitors (TKIs). Cases of NSCLC transforming into SCLC have been discovered. However, we lack concentrated data on the characteristics of this population and the transformed SCLC to aid our insight of the biology and clinical value of NSCLC transforming with positive.

METHODS

We systematically reviewed the published literatures and summarized the pathological and clinical characteristics, and the prognosis, of published cases.

RESULTS

140 patients with lung adenocarcinoma (LUAD) were included in this study, with a median age of 56.8 years. The median time from the first diagnosis of LUAD transforming to SCLC (ttSCLC) was 20.0 months. The median overall survival (mOS) after the diagnosis of SCLC was 11.0 months (95% CI, 7.41 to 14.59 months). In the univariate analysis, ever smoking (either former or current) was a promising predictor of a shorter ttSCLC (HR, 1.73; 95% CI, 1.14 to 2.62; P = 0.010). TKIs therapy administered as a second line and beyond treatment was related to a significant delay in SCLC onset compared to first-line therapy (HR, 0.62; 95% CI, 0.40 to 0.96; P = 0.031). The median progression-free survival (mPFS) on first-line platinum plus etoposide after the conversion to SCLC was 3.0 months. Female appeared to be related to worse outcomes after transformation of SCLC.

CONCLUSION

Transformed SCLC exhibited poor response to primary SCLC classic chemotherapy and immunotherapy. It carries a worse prognosis. Exploring novel therapeutic strategies for transformed SCLC is imperative.

Using ex vivo bioengineered lungs to model pathologies and screening therapeutics: A proof-of-concept study

Respiratory diseases, claim over eight million lives annually. However, the transition from preclinical to clinical phases in research studies is often hindered, partly due to inadequate representation of preclinical models in clinical trials. To address this, we conducted a proof-of-concept study using an ex vivo model to identify lung pathologies and to screen therapeutics in a humanized rodent model. We extracted and decellularized mouse heart-lung tissues using a detergent-based technique. The lungs were then seeded and cultured with human cell lines (BEAS-2B, A549, and Calu3) for 6-10 days, representing healthy lungs, cancerous states, and congenital pathologies, respectively. By manipulating cultural conditions and leveraging the unique characteristics of the cell lines, we successfully modeled various pathologies, including advanced-stage solid tumors and the primary phase of SARS-CoV-2 infection. Validation was conducted through histology, immunofluorescence staining, and pathology analysis. Additionally, our study involved pathological screening of the efficacy and impact of key anti-neoplastic therapeutics (Cisplatin and Wogonin) in cancer models. The results highlight the versatility and strength of the ex vivo model in representing crucial lung pathologies and screening therapeutics during the preclinical phase. This approach holds promise for bridging the gap between preclinical and clinical research, aiding in the development of effective treatments for respiratory diseases, including lung cancer.

Noninvasive Lung Cancer Subtype Classification Using Tumor-Derived Signatures and cfDNA Methylome

Accurate diagnosis of lung cancer is important for treatment decision-making. Tumor biopsy and histologic examination are the standard for determining histologic lung cancer subtypes. Liquid biopsy, particularly cell-free DNA (cfDNA), has recently shown promising results in cancer detection and classification. In this study, we investigate the potential of cfDNA methylome for the noninvasive classification of lung cancer histologic subtypes. We focused on the two most prevalent lung cancer subtypes, lung adenocarcinoma and lung squamous cell carcinoma. Using a fragment-based marker discovery approach, we identified robust subtype-specific methylation markers from tumor samples. These markers were successfully validated in independent cohorts and associated with subtype-specific transcriptional activity. Leveraging these markers, we constructed a subtype classification model using cfDNA methylation profiles, achieving an AUC of 0.808 in cross-validation and an AUC of 0.747 in the independent validation. Tumor copy-number alterations inferred from cfDNA methylome analysis revealed potential for treatment selection. In summary, our study demonstrates the potential of cfDNA methylome analysis for noninvasive lung cancer subtyping, offering insights for cancer monitoring and early detection.

SIGNIFICANCE

This study explores the use of cfDNA methylomes for the classification of lung cancer subtypes, vital for effective treatment. By identifying specific methylation markers in tumor tissues, we developed a robust classification model achieving high accuracy for noninvasive subtype detection. This cfDNA methylome approach offers promising avenues for early detection and monitoring.

Clinical Outcome of Stereotactic Body Radiotherapy in Patients with Early-Stage Lung Cancer with Ground-Glass Opacity Predominant Lesions: A Single Institution Experience

PURPOSE

The detection rate of early-stage lung cancer with ground-glass opacity (GGO) has increased, and stereotactic body radiotherapy (SBRT) has been suggested as an alternative to surgery in inoperable patients. However, reports on treatment results are limited. Therefore, we performed a retrospective study to investigate the clinical outcome after SBRT in patients with early-stage lung cancer with GGO-predominant tumor lesions at a single institution.

MATERIALS AND METHODS

This study included 89 patients with 99 lesions who were treated with SBRT for lung cancer with GGO-predominant lesions that had a consolidation-to-tumor ratio of ≤0.5 at Asan Medical Center between July 2016 and July 2021. A median total dose of 56.0 Gy (range, 48.0-60.0) was delivered using 10.0-15.0 Gy per fraction.

RESULTS

The overall follow-up period for the study was median 33.0 months (range, 9.9 to 65.9 months). There was 100% local control with no recurrences in any of the 99 treated lesions. Three patients had regional recurrences outside of the radiation field, and three had distant metastasis. The 1-year, 3-year, and 5-year overall survival rates were 100.0%, 91.6%, and 82.8%, respectively. Univariate analysis revealed that advanced age and a low level of diffusing capacity of the lungs for carbon monoxide were significantly associated with overall survival. There were no patients with grade ≥3 toxicity.

CONCLUSION

SBRT is a safe and effective treatment for patients with GGO-predominant lung cancer lesions and is likely to be considered as an alternative to surgery.

Gene-level dissection of chromosome 3q locus amplification in squamous cell carcinoma of the lung using the nCounter assay

BACKGROUND

Amplification of the 3q region has been identified as a useful biomarker for the diagnosis and treatment of squamous cell carcinoma (SqCC). This region contains genes such as PIK3CA and YEATS2, which have been linked to the prognosis of SqCC.

METHODS

The NanoString nCounter assay is a powerful tool for identifying genetic alterations that affect the progression and prognosis of SqCC. The NanoString nCounter assay was used to identify a subgroup of patients with gene level gain in the 3q region.

RESULTS

Gene level gain in the 3q region was more frequent in SqCC than in adenocarcinoma. We found that genes such as PIK3CA and YEATS2 in the 3q region were associated with the prognosis of SqCC. Therefore, identifying a subgroup of patients with gene level gain in the 3q region using the NanoString nCounter assay can aid in selecting appropriate treatment options and improving prognostic predictions for SqCC patients.

CONCLUSION

Amplification of the 3q region in SqCC of lung cancer is a useful biomarker for diagnosis and treatment. The NanoString nCounter assay is a powerful tool for identifying specific genetic alterations that affect the progression and prognosis of SqCC. Our study highlights the importance 3q amplification and its associated genes in lung cancer.

Hepatoid Adenocarcinoma of the Lung: A Review of the Most Updated Literature and a Presentation of Three Cases

In a Surgical Thoracic Center, two females and a man were unexpectedly diagnosed with hepatoid adenocarcinoma of the lung (HAL) in a single year. HAL is a rare lung cancer with pathological features of hepatocellular carcinoma with no evidence of liver tumor or other primitive sites of neoplasms. As of today, a comprehensive treatment is still not written. We reviewed the most updated literature on HAL, aiming to highlight the proposed treatments available, and comparing them in terms of survival. General hallmarks of HAL are confirmed: it typically affects middle-aged, heavy-smoker males with a median of 5 cm bulky right upper lobe mass. Overall survival remains poor (13 months), with a longer but non-significant survival in females. Treatments are still unsatisfactory today: surgery guarantees a small benefit compared to non-operated HALs, and only N0 patients demonstrated improved survival (p = 0.04) compared to N1, N2, and N3. Even though the histology is fearsome, these are probably the patients who will benefit from upfront surgery. Chemotherapy seemed to behave as surgery, and there is no statistical difference between chemotherapy only, surgery, or adjuvant treatments, even though adjuvant treatments tend to be more successful. New chemotherapies have been reported with notable results in recent years, such as Tyrosine Kinase Inhibitors and monoclonal antibodies. In this complicated picture, new cases are needed to further build shared evidence in terms of diagnosis, treatments, and survival opportunities.

Histologic transformation in lung cancer: when one door shuts, another opens

Histologic transformation (HT) is a major cause of drug resistance to therapy in patients with lung cancer. HTs to small-cell lung cancer (SCLC) have been reported frequently in patients with epidermal growth factor receptor (EGFR)-mutated lung cancer. Although HTs have an impact on the clinical outcomes in patients owing to a high refractoriness to treatments, there is limited data on the prevalence, causes, mechanisms, treatment efficacy, and future treatment strategies. In this review, we assess the literature regarding HTs comprehensively, including those describing EGFR-tyrosine kinase inhibitors, other molecular targeted drugs, and immune checkpoint inhibitors. Furthermore, we discuss the mechanisms of HTs and the lineage plasticity to SCLC and squamous cell carcinoma in lung cancer. In addition, we summarize the treatment efficacy and future perspectives of HTs in patients with lung cancer, and propose better management strategies for this group of patients.

Challenges and Opportunities for Immunoprofiling Using a Spatial High-Plex Technology: The NanoString GeoMx® Digital Spatial Profiler

Characterization of the tumor microenvironment through immunoprofiling has become an essential resource for the understanding of the complex immune cell interactions and the assessment of biomarkers for prognosis and prediction of immunotherapy response; however, these studies are often limited by tissue heterogeneity and sample size. The nanoString GeoMx^® Digital Spatial Profiler (DSP) is a platform that allows high-plex profiling at the protein and RNA level, providing spatial and temporal assessment of tumors in frozen or formalin-fixed paraffin-embedded limited tissue sample. Recently, high-impact studies have shown the feasibility of using this technology to identify biomarkers in different settings, including predictive biomarkers for immunotherapy in different tumor types. These studies showed that compared to other multiplex and high-plex platforms, the DSP can interrogate a higher number of biomarkers with higher throughput; however, it does not provide single-cell resolution, including co-expression of biomarker or spatial information at the single-cell level. In this review, we will describe the technical overview of the platform, present current evidence of the advantages and limitations of the applications of this technology, and provide important considerations for the experimental design for translational immune-oncology research using this tissue-based high-plex profiling approach.