The IASLC Lung Cancer Staging Project: Proposals for Coding T Categories for Subsolid Nodules and Assessment of Tumor Size in Part-Solid Tumors in the Forthcoming Eighth Edition of the TNM Classification of Lung Cancer

Imaging and Management of Subsolid Lung Nodules

Subsolid nodules (SSNs) are increasingly encountered in chest computed tomography (CT) imaging and clinical practice, as awareness of their significance and CT utilization grows. Either part-solid or solely ground-glass in attenuation, SSNs are shown to correlate with lung adenocarcinomas and their precursors, although a differential diagnosis is to be considered that includes additional neoplastic and inflammatory etiologies. This review discusses the differential diagnosis for SSNs, imaging and clinical features, and pathology that are helpful when making management decisions that may include PET/CT, biopsy, or surgery. Potential pitfalls in nodule characterization and management will be highlighted, to aid in managing SSNs appropriately.

Clinical and Genetic Characteristics of Early-Onset Lung Adenocarcinoma in a Large Chinese Cohort

BACKGROUND

The characteristics of early-onset lung adenocarcinoma (EOLA) have not been extensively studied. Our research aimed to comprehensively assess the clinical and genetic features of EOLA.

METHODS

We conducted a retrospective analysis of surgically resected lung adenocarcinoma patients, categorizing them into the EOLA group (aged <40 years) and the late-onset lung adenocarcinoma (LOLA) group (aged >60 years). A comparative investigation of clinical, germline, and genomic features was conducted. Propensity score matching was used to balance baseline characteristics for gene mutation analysis.

RESULTS

We enrolled 487 EOLA and 2507 LOLA patients. EOLA patients exhibited a higher female-to-male ratio (2.55 vs 1.19) and a higher proportion of family history of lung cancer in the ground-grass opacity subgroup (12.7% vs 8.9%). The EOLA group exhibited higher rates of earlier stage in the ground-grass opacity subgroup and solid subgroup. Preinvasive adenocarcinoma was the dominant histologic subtype in the EOLA group within the ground-glass opacity subgroup (73.8% vs 25.6%). After propensity score matching, we analyzed 241 stage 0/I patients with available genetic test results. Significant disparities in gene mutation rates emerged between the EOLA and LOLA patients, including Erb-B2 receptor tyrosine kinase 2 (ERBB2; 38.0% vs 2.8%), epidermal growth factor receptor (EGFR; 36.0% vs 64.5%), MET (0.0% vs 7.1%), neurofibromin 1 (NF1; 0.0% vs. 5.7%), and anaplastic lymphoma kinase (ALK) fusion (10.0% vs 1.4%).

CONCLUSIONS

EOLA patients exhibited distinct clinical and genetic characteristics compared with LOLA patients.

Qualitative and quantitative CT analyses of the solid component in lung adenocarcinoma for predicting invasiveness

PURPOSE

This study aimed to evaluate the CT findings of lung adenocarcinoma with solid components and to determine the difference between adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) with invasive adenocarcinoma (IAC).

MATERIALS AND METHODS

A total of 54 cases were included in this study. The diagnoses of lung adenocarcinoma consisted of AIS or MIA (n = 20) and IAC (n = 34). The following factors were evaluated on CT images: part-solid nodule or solid nodule, presence of air bronchogram, air space, calcification within the tumor, presence of interstitial pneumonia and emphysema, diameters of the tumor and solid component, and CT values of the solid component. The volume and CT number histograms, including the 50th, 75th, and 100th percentiles of solid component were obtained using a software program. The CT criteria were compared between AIS, MIA, and IAC, and an indicator of differentiation was considered.

RESULTS

Part-solid nodules were observed more frequently in AIS and MIA (85.0%) than in IAC (55.9%). All criteria for quantitative analysis showed significant differences between AIS or MIA and IAC, and the diameter of the solid component in the mediastinal window was an indicator of differentiation (p = 0.0006; odds ratio, 1.4; 95% confidence interval, 1.2-1.8).

CONCLUSION

The diameter of the solid component on the mediastinal window was considered an indicator of differentiation between AIS, MIA, and IAC.

CONDENSED ABSTRACT

Quantitative data of solid component, including both manual measurements and evaluation using CT software, are correlated with pathological invasiveness. Diameter of the solid component in the mediastinal window would be an indicator of IAC.

Comparative validation of clinical staging based on solid component versus total tumor size in resected lung adenocarcinoma

OBJECTIVES

To compare clinical staging based on total tumor size with that of solid component size using the same criteria.

MATERIALS AND METHODS

Patients who underwent curative resection for clinical stage IA1-IB adenocarcinoma between 2011 and 2021 were retrospectively included. Patients were re-staged according to the criteria of the current TNM staging using total tumor size (cStagetotal) and solid component size (cStagesolid). Discrimination and prognostication for overall survival and freedom from recurrence were compared between cStagetotal and cStagesolid. The correlation with pathologic risk factors (high-grade pattern, lymphovascular invasion, and pathologic lymph node metastasis) was assessed.

RESULTS

A total of 4680 patients were included. From cStagetotal to cStagesolid, 32.6% of patients (1525/4680) were downstaged. Overall survival stratification within clinical stage IA-3 for subsolid lesions was enabled only with cStagesolid. Both cStagetotal and cStagesolid demonstrated mortality risk stratification between neighboring stages from IA1 to IB (all p < 0.05); however, discrimination (C-index: 0.732 vs. 0.721) and prognostication (Akaike Information Criterion (AIC): 8609 vs. 8645; R2: 0.084 vs. 0.077) were better in cStagesolid. Additionally, cStagesolid showed an improved correlation with pathologic risk factors and pathologic lymph node metastasis (both any pN and pN2). cStagesolid also showed improved discrimination (C-index: 0.731 vs. 0.722) and prognostication (AIC: 12,257 vs. 12,316; R2: 0.102 vs. 0.091) than cStagetotal for freedom from recurrence.

CONCLUSION

Using the same size criteria, clinical staging based on solid component size provides enhanced performance and correlation with pathologic risk factors compared to total tumor size.

KEY POINTS

Question A direct comparative validation of clinical staging based on solid component size versus total tumor size under the same criteria has not been conducted. Findings Correlation with pathologic risk factors and lymph node metastasis, especially pN2, was stronger in clinical staging based on solid component. Clinical relevance It is reasonable for future revisions to be based on the current scheme using solid component size.

Impact of tumor size by clinical N subclassification and histology in trimodality-treated N2 non-small cell lung cancer

The evolving TNM classification has emphasized the tumor size's role in NSCLC prognosis, reclassifying stage IIIA patients from the previous edition as stage IIIB (T3-4N2M0, 8th edition). However, the prognostic implications of tumor size and survival in stage III NSCLC patients undergoing neoadjuvant therapy remain unexplored. Therefore, we investigated the association between tumor size and mortality in N2 non-small cell lung cancer (NSCLC) patients undergoing neoadjuvant concurrent chemoradiotherapy followed by surgery (trimodality therapy), considering the number of metastatic N2 stations and histology. We analyzed 756 patients with stage III (T1-3N2) NSCLC who underwent trimodality therapy, excluding those with T3 tumors with invasion components or additional nodules (2003-2019). Overall survival was compared using the Cox-proportional hazards model, while the tumor size-survival relationship was estimated using restricted cubic splines. Using 8th TNM edition, 32.1%, 48.5%, and 19.3% were clinical T1, T2, and T3. During a median follow-up of 53.5 months, 398 patients died. The adjusted hazard ratios for overall survival comparing T2 and T3 to T1 were 1.46 (95% confidence interval, 1.14-1.85) and 1.48 (1.10-1.99). For the extent of clinical N2, large tumor size increased the mortality risk in patients with N2b but not in N2a. Tumor size did not increase mortality risk in squamous cell carcinoma patients; however, the mortality risk was increased with larger tumors in adenocarcinoma. These findings raise the importance of considering tumor size in treatment planning and suggesting tailored strategies.

Radiographical consolidation tumor size and preoperative clinical characteristics are significantly correlated with the postoperative survival of patients with part-solid and pure-solid adenocarcinomas: a propensity score-matched analysis

PURPOSE

Patients with part-solid adenocarcinomas treated by surgery generally have more favorable outcomes than those with pure-solid adenocarcinomas. We conducted this study to understand the effects of the lepidic components and preoperative characteristics on the postoperative survival of patients with part-solid adenocarcinomas.

METHODS

The subjects of this retrospective study were 313 patients with stage 1 part-solid adenocarcinomas and 634 patients with pure-solid adenocarcinomas, treated at our institution between 2006 and 2020. Propensity score matching was performed to analyze survival in an unmatched cohort (PSM0, n = 313 vs. 634); a matched cohort based on the consolidation diameter (PSM1, n = 217 each); and a matched cohort based on 11 clinical characteristics (PSM2, n = 103 each). Multivariate analysis was also performed.  RESULTS: The 5-year overall/recurrence-free survival rates for part-solid and pure-solid adenocarcinomas were 90.2%/79.3% and 80.8%/66.0% in the PSM0 cohort (P < 0.0001), 87.4%/79.2% and 76.3%/68.6% in the PSM1 cohort (P < 0.05), and 91.6%/92.1% and 76.6%/79.0% in the PSM2 cohort (P > 0.05), respectively. Multivariate analysis revealed that male sex (P = 0.04) and the carcinoembryonic antigen value (P < 0.0001) were significant factors affecting overall survival, while the carcinoembryonic antigen value (P = 0.0002) and consolidation tumor size (P = 0.002) affected recurrence-free survival. The lepidic component was not related to overall (P = 0.45) or recurrence-free (P = 0.78) survival.

CONCLUSIONS

Preoperative factors are strongly associated with "consolidation size", which could be the "representative factor" indicating the malignant potential in adenocarcinomas being consistent with the current eighth edition of the TNM.

Multidisciplinary expert consensus on diagnosis and treatment of multiple lung cancers

The rising incidence of multiple lung cancers (MLCs), encompassing multiple primary lung cancers (MPLCs) and intrapulmonary metastasis (IPM), poses two significant clinical challenges. First, distinguishing between MPLC and IPM remains difficult due to insufficiently accurate criteria and ambiguous integration of genetic testing. Second, standardized therapeutic protocols are still lacking. To address these issues, the Lung Cancer Expert Committee of China Anti-Cancer Association (CACA) assembled a multidisciplinary expert panel spanning thoracic surgery, pulmonary medicine, oncology, radiology, and pathology. Following a comprehensive literature review ending on October 23, 2024, the panel engaged in iterative discussions and conducted two rounds of expert voting, culminating in 25 evidence-based recommendations across five key domains: epidemiology, pre-treatment evaluation, definitive diagnostics, surgical treatment, and non-surgical treatment. This consensus provides clinicians with practical guidance to enhance diagnostic precision and therapeutic decision-making in MLC management while highlighting unmet needs to inform future guideline development.

Molecular characterization of early-stage lung adenocarcinoma presenting as subsolid nodules in a real-life European cohort

OBJECTIVES

Subsolid nodules emerged as frequent radiological variants of lung adenocarcinoma. Radiological features including solid-component prevalence and larger tumour dimensions prompt tumoral invasiveness guiding prognosis and management. Thus, we aimed to clarify the molecular grounds that dictate these radiological appearances and clinical behaviour in a real-life European-cohort. Additionally, following the growing interest toward targeted-therapies in early-stage diseases, we aimed to present real-life epidemiological data of actionable mutations in these patients.

METHODS

In this retrospective single-centre study, targeted next-generation sequencing was performed continuatively in all the resected subsolid lung adenocarcinomas in the period between May 2016 and December 2023. Clinico-radiological data were collected. The genetic landscape of our real-life European subsolid adenocarcinoma population is defined. Common and actionable mutations (frequency > 5%) relation to key clinico-radiological features are evaluated.

RESULTS

Overall, 156 subsolid adenocarcinomas were analysed. KRAS-mutations, mostly KRAS p.G12C, were the most prevalent followed by EGFR, including 25% uncommon EGFR-mutations, TP53 and MET mutations. Amongst the clinico-radiological variables, KRAS-mutations and KRAS p.G12C-mutation were associated to smoking history (≥ 20 pack/years), aggressive histologic subtype and higher consolidation-to-tumor ratio (CTR). Moreover, KRAS-mutated nodules had faster tumour-doubling-time. Conversely, EGFR-mutations were associated to female sex and lower CTR. The latter not being confirmed in common EGFR-mutations. Additionally, in common EGFR-mutated nodules, aggressive histological components were rarer.

CONCLUSION

Our study presents the molecular profile of subsolid lung adenocarcinoma in a real-life European-cohort. KRAS-mutations were the most prevalent, and were related to smoking history, higher CTR and faster growth. Conversely, common EGFR-mutations were rarer than expected and unrelated to smoking history and radiological features.

Data set for the reporting of lung cancer: recommendations from the International Collaboration on Cancer Reporting (ICCR)

Lung cancer is the leading cause of cancer related deaths worldwide, although some patients with early-stage disease can be cured with surgical resection. Standardised reporting of all clinically relevant pathological parameters is essential for best patient care and is also important for ongoing data collection and refinement of important pathological features that impact patient prognosis, staging and clinical care. Using the established International Collaboration on Cancer Reporting (ICCR) procedure, a representative international expert panel of nine lung pathologists as well as an oncologist was convened. Essential core elements and suggested non-core elements were identified for inclusion in the resected lung cancer pathology data set based on predetermined levels of evidence as well as consensus expert opinion. A lung cancer histopathology reporting guide was developed that includes relevant clinical, macroscopic, microscopic and ancillary testing. Critical review and discussion of current evidence was incorporated into the new data set including changes from the 2021 World Health Organisation (WHO) Classification of Thoracic Tumours, fifth edition, new requirements for grading invasive non-mucinous adenocarcinomas, assessment of response to neoadjuvant therapy and requirements for molecular testing in early-stage resected lung carcinomas. This ICCR data set represents incorporation of all relevant parameters for histology reporting of lung cancer resection specimens. Routine use of this data set is recommended for all pathology reporting of resected lung cancer and it is freely available worldwide on the ICCR website (https://www.iccr-cancer.org/datasets/published-datasets/). Widespread implementation will help to ensure consistent and comprehensive pathology reporting and data collection essential for lung cancer patient care, clinical trials and other research.

Clinical TNM Lung Cancer Staging: A Diagnostic Algorithm with a Pictorial Review

Lung cancer is a prevalent malignant disease with the highest mortality rate among oncological conditions. The assessment of its clinical TNM staging primarily relies on contrast-enhanced computed tomography (CT) of the thorax and proximal abdomen, sometimes with the addition of positron emission tomography/CT scans, mainly for better evaluation of mediastinal lymph node involvement and detection of distant metastases. The purpose of TNM staging is to establish a universal nomenclature for the anatomical extent of lung cancer, facilitating interdisciplinary communication for treatment decisions and research advancements. Recent studies utilizing a large international database and multidisciplinary insights indicate a need to update the TNM classification to enhance the anatomical categorization of lung cancer, ultimately optimizing treatment strategies. The eighth edition of the TNM classification, issued by the International Association for the Study of Lung Cancer (IASLC), transitioned to the ninth edition on 1 January 2025. Key changes include a more detailed classification of the N and M descriptor categories, whereas the T descriptor remains unchanged. Notably, the N2 category will be split into N2a and N2b based on the single-station or multi-station involvement of ipsilateral mediastinal and/or subcarinal lymph nodes, respectively. The M1c category will differentiate between single (M1c1) and multiple (M1c2) organ system involvement for extrathoracic metastases. This review article emphasizes the role of radiologists in implementing the updated TNM classification through CT imaging for correct clinical lung cancer staging and optimal patient management.

Prognosis of surgically resected clinical stage 1A non-small cell lung cancers manifesting as a subsolid nodule on computed tomography including pure ground glass nodules

OBJECTIVES

This is a protocol for a Cochrane Review (prognosis). The objectives are as follows: To quantify the risk of tumour relapse/recurrence after a surgical resection of stage 1A non-small cell lung cancer (NSCLC) as manifested on computed tomography (CT) imaging as a subsolid nodule.

CENPF (+) cancer cells promote malignant progression of early-stage TP53 mutant lung adenocarcinoma

The prevention and precise treatment of early-stage lung adenocarcinoma (LUAD) characterized by small nodules (stage IA) remains a significant challenge for clinicians, which is due largely to the limited understanding of the oncogenic mechanisms spanning from preneoplasia to invasive adenocarcinoma. Our study highlights the pivotal role of cancer cells exhibiting high expression of centromere protein F (CENPF), driven by TP53 mutations, which become increasingly prevalent during the transition from preneoplasia to invasive LUAD. Biologically, cancer cells (CENPF+) exhibited robust proliferative and stem-like capabilities, thereby propelling the malignant progression of early-stage LUAD. Clinically, autoantibodies against CENPF in the serum and elevated cancer cells (CENPF+) in tissue correlated positively with the progression of early-stage LUAD, especially those in stage IA. Our findings suggest that cancer cells (CENPF+) play a central role in orchestrating the malignant evolution of LUAD and hold potential as a novel biomarker for early-stage detection and management of the disease.

Safety and Efficacy of Salvage Surgery after Treatment With Immune-Checkpoint Adjuvant Inhibitors for Advanced Non-Small Cell Lung Cancer: A Multicentric Study

OBJECTIVE

In advanced non-small cell lung cancer (NSCLC), immune-checkpoint inhibitors (ICIs) can achieve significant clinical responses. This raises the question of whether to consider salvage surgery as a curative treatment option. Few case series reported encouraging results in terms of pathological response. However, intraoperative risk and postoperative morbidity have been highlighted. This study aims to assess the safety and feasibility of surgery after ICIs administration and to evaluate its effectiveness on the final pathological examination.

METHODS

We retrospectively identified stages III-IVA NSCLC consecutive patients who underwent surgery with radical intent after ICIs at three National Centers (2016-2022). Before treatment, all patients were considered unresectable by a multidisciplinary discussion. After surgery, pathological response was evaluated according to the International Association for the Study of Lung Cancer (IASLC) recommendation.

RESULTS

Thirty-one patients were included; pretreatment clinical stage was: IIIA in 4 patients (10%), IIIB in 13 (42%), IIIC in 3 (13%), and IVA in 11 (35%). Median treatment duration was four cycles. Only anatomical resections were performed, with lobectomy that represent the main type of resection (22 patients, 74%). A minimally invasive approach was performed in 10 patients (32%), with a conversion rate of 0%. Postoperative complications were observed in eight patients (25%). Complete pathologic response (CPR) and major pathologic response (MPR) were 48% and 16%, respectively. Two and 3-years survival were 88%.

CONCLUSIONS

Based on our experience, salvage surgery of advanced NSCLC treated with ICIs confirm his feasibility and safety in responder patients. Moreover, it is associated with low morbidity, high CPR rate, and satisfying medium-term survival.

Impact of histopathological subtypes on invasive lung adenocarcinoma: from epidemiology to tumour microenvironment to therapeutic strategies

Lung adenocarcinoma is the most prevalent type of lung cancer, with invasive lung adenocarcinoma being the most common subtype. Screening and early treatment of high-risk individuals have improved survival; however, significant differences in prognosis still exist among patients at the same stage, especially in the early stages. Invasive lung adenocarcinoma has different histological morphologies and biological characteristics that can distinguish its prognosis. Notably, several studies have found that the pathological subtypes of invasive lung adenocarcinoma are closely associated with clinical treatment. This review summarised the distribution of various pathological subtypes of invasive lung adenocarcinoma in the population and their relationship with sex, smoking, imaging features, and other histological characteristics. We comprehensively analysed the genetic characteristics and biomarkers of the different pathological subtypes of invasive lung adenocarcinoma. Understanding the interaction between the pathological subtypes of invasive lung adenocarcinoma and the tumour microenvironment helps to reveal new therapeutic targets for lung adenocarcinoma. We also extensively reviewed the prognosis of various pathological subtypes and their effects on selecting surgical methods and adjuvant therapy and explored future treatment strategies.

Identifying invasiveness to aid lung adenocarcinoma diagnosis using deep learning and pathomics

Most classification efforts for primary subtypes of lung adenocarcinoma (LUAD) have not yet been integrated into clinical practice. This study explores the feasibility of combining deep learning and pathomics to identify tumor invasiveness in LUAD patients, highlighting its potential clinical value in assisting junior and intermediate pathologists. We retrospectively analyzed whole slide image (WSI) data from 289 patients with surgically resected ground-glass nodules (GGNs). First, three ResNet deep learning models were used to identify tumor regions. Second, features from the best-performing model were extracted to build pathomics using machine learning classifiers. Third, the accuracy of pathomics in predicting tumor invasiveness was compared with junior and intermediate pathologists' diagnoses. Performance was evaluated using the area under receiver operator characteristic curve (AUC). On the test cohort, ResNet18 achieved the highest AUC (0.956) and sensitivity (0.832) in identifying tumor areas, with an accuracy of 0.904; Random Forest provided high accuracy and AUC values of 0.814 and 0.807 in assessing tumor invasiveness. Pathology assistance improved diagnostic accuracy for junior and intermediate pathologists, with AUC values increasing from 0.547 to 0.759 and 0.656 to 0.769. This study suggests that deep learning and pathomics can enhance diagnostic accuracy, offering valuable support to pathologists.

Prognostic Impact of Non-Predominant Lepidic Components in Pathologic Stage I Invasive Nonmucinous Adenocarcinoma

INTRODUCTION

This study investigated the prognostic impact of non-predominant lepidic components in invasive nonmucinous adenocarcinoma.

METHODS

Patients who underwent lobectomy and were diagnosed with stage I nonmucinous, non-lepidic-predominant invasive adenocarcinoma based on pathologic findings were included. Tumors were staged according to the eighth edition of TNM classification and categorized on the basis of the presence of lepidic components in the final pathologic findings. Overall survival (OS) and recurrence-free survival (RFS) were analyzed before and after applying inverse probability of treatment weighting. Competing risk analyses for recurrence were also compared in the two groups.

RESULTS

Of the 1270 patients, 858 (67.6%) had lepidic components (+). The pathologic stage and histologic grade were higher in the lepidic (-) group (p < 0.001, respectively). The 5-year OS and RFS were significantly worse in the lepidic (-) group than in the lepidic (+) group (OS: 88.2% versus 94.9%, p < 0.001; RFS: 79.4% versus 91.9%, p < 0.001). These trends were consistent after weighted analysis (OS: 92.4% versus 96.4%, p = 0.029; RFS: 85.6% versus 92.3%, p = 0.007). The 5-year cumulative incidence of any recurrence was 14.0% in the lepidic (-) group and 4.1% in the lepidic (+) group (p < 0.001). Multivariable Fine-Gray regression analysis found that the lepidic (+) group exhibited a lower risk of recurrence than did the lepidic (-) group (hazard ratio = 0.52, 95% confidence interval: 0.29-0.93, p = 0.031).

CONCLUSIONS

In pathologic stage I invasive nonmucinous adenocarcinoma, the presence of histologically diagnosed non-predominant lepidic components might be associated with a better prognosis after curative surgery.

Reassessment of the Prognostic Implication of Ground-Glass Opacity: An Investigation Into Hypermetabolic Clinical Stage IA Lung Adenocarcinoma

BACKGROUND

Subsolid lung nodules represent a distinct group of lung cancers with less-aggressive biological behavior and favorable survival. We aimed to examine the prognostic impact of the ground-glass opacity (GGO) in clinical stage IA (cIA) lung adenocarcinoma with high metabolic activity.

METHODS

A retrospective study was conducted among patients with resected hypermetabolic and/or pure-solid cIA lung adenocarcinoma from a single institution database. The primary outcome was recurrence-free survival (RFS). The secondary outcomes included overall survival, pathological nodal upstaging, and recurrence rate.

RESULTS

A total of 621 patients were reviewed and classified into three groups: patients with low metabolic, solid nodules (SNs) into group A (N = 128), patients with hypermetabolic ground-glass nodules (GGNs) into group B (N = 105), and patients with hypermetabolic SNs into group C (N = 388). The five-year RFS of group B was significantly better than that of group C in the cT1a + T1b (93.3% vs. 72.5%, p = 0.002) subgroup but not in the cT1c (73.4% vs. 69.0%, p = 0.23) subgroup. Multivariable analysis showed that GGO component was an independent prognostic factor of RFS (hazard ratio [HR] = 0.41, 95% confidence interval [CI]: 0.19-0.89, p = 0.02) and protective factor of nodal upstaging (odds ratio [OR] = 0.44, 95% CI: 0.21-0.94, p = 0.03) among the hypermetabolic subgroup. All except one postoperative recurrence occurred in GGNs with solid component size > 2 cm.

CONCLUSIONS

The presence of GGO component was an independent prognostic factor even in hypermetabolic cIA lung adenocarcinoma. However, the oncologic outcomes of hypermetabolic GGNs were not equally favorable in different T categories.

Asian Thoracic Oncology Research Group expert consensus statement on the peri-operative management of non-small cell lung cancer

The peri-operative management of non-small cell lung cancer (NSCLC) in earlier stage disease has seen significant advances in recent years with the incorporation of immune checkpoint inhibitors and targeted therapy. However, many unanswered questions and challenges remain, including the application of clinical trial data to routine clinical practice. Recognising the unique demographic profile of Asian patients with NSCLC and heterogeneous healthcare systems, the Asian Thoracic Oncology Research Group (ATORG) convened a consensus meeting in Singapore on 26 April 2024 to discuss relevant issues spanning diagnostic testing to post-neoadjuvant treatment considerations and future directions. An interdisciplinary group of 19 experts comprising medical oncologists, thoracic surgeons, radiation oncologists, pulmonologists and pathologists from Singapore, Hong Kong, Mainland China, Korea, Japan, Taiwan, India, Malaysia, Thailand, Vietnam and Australia met to discuss emerging data, identify existing gaps in clinical care and develop a multidisciplinary, multinational expert consensus statement on the peri-operative management of NSCLC tailored to the Asia-Pacific region.

Highly proliferating cancer cells function as novel prognostic biomarkers for lung adenocarcinoma with particular usefulness for stage IA risk stratification

BACKGROUND

The refinement of risk stratification in lung adenocarcinoma (LUAD) plays a pivotal role in advancing precision medicine; however, the current staging classification falls short of comprehensiveness, particularly in the case of stage IA patients. We aimed to molecularly stratify LUAD patients especially for stage IA.

METHODS

We analysed tumour heterogeneity and identified highly proliferating cancer cells (HPCs) in LUAD by performing single-cell RNA sequencing (scRNA-seq) analysis, immunohistochemical (IHC) staining using a tissue microarray, flow cytometry and biological experiments. Then, we quantified the content of HPCs in nine LUAD datasets by single-sample gene set enrichment analysis and evaluated the relationship between the percentage of HPCs and overall survival (OS). Next, we analysed the OS predictive effect of HPCs at different LUAD stages, especially for stage I risk stratification. Furthermore, we established a prognostic prediction model based on HPC-associated genes for clinical application. The above findings were validated in another five LUAD datasets. Finally, we explored the relationship between HPCs and the progressive pathological evolution of early-stage LUAD and the driving mutations by scRNA-seq, bulk RNA-seq and IHC staining.

RESULTS

LUAD tissues carry a small proportion of HPCs, which show potential for malignant proliferation and intense interactions with the microenvironment. A high HPC content is an independent risk factor for OS in LUAD patients, even in stage IA patients. HPCs can be used to establish a cut-off point for the prognosis of stage IA disease, with patients with a higher risk showing a prognosis similar to that of patients with stage IB disease. We built an R package (HSurADs) based on HPC-associated genes, which exhibited good efficacy for the prognostic prediction of LUAD. HPCs gradually increase with the pathological evolution of early-stage LUAD, which may be affected by TP53 mutations.

CONCLUSION

The HPC content can be used as a novel prognostic factor for LUAD, especially for stage IA risk stratification.

Radiologists Versus AI-Based Software: Predicting Lymph Node Metastasis and Prognosis in Lung Adenocarcinoma From CT Under Various Image Display Conditions

PURPOSE

To compare the variability of quantitative values from lung adenocarcinoma CT images independently assessed by 2 radiologists and AI-based software under different display conditions, and to identify predictors of pathological lymph node metastasis (LNM), disease-free survival (DFS), and overall survival (OS).

METHODS

Preoperative CT images of 307 patients were displayed under 4 conditions: lung-1, lung-2, mediastinum-1, and mediastinum-2. Two radiologists (R1, R2) measured total diameter (tD) and the longest solid diameter (sD) under each condition. The AI-based software automatically detected lung nodules, providing tD, sD, total volume (tV), and solid volume (sV).

RESULTS

All measurements by R1 and R2 with AI-based software were identical. Four out of the 8 measurements showed significant variation between R1 and R2. For LNM, multivariate logistic regression identified significant indicators including sD at mediastinum-2 of R1, sD at mediastinum-1 and mediastinum-2 of R2, tV, and the proportion of sV to tV (sV/tV) of AI-based software. For DFS, multivariate Cox regression identified sD at lung-1 of R1, the proportions of sD to tD at lung-2 of R1, sD at lung-2 and mediastinum-1 of R2, tV, and sV/tV of AI-based software as significant. For OS, multivariate Cox regression identified sD at lung-1 and mediastinum-2 of R1, tD at lung-2 of R2, sD at mediastinum-1 of R2, sV, and sV/tV of AI-based software as significant.

CONCLUSION

Radiologists' CT measurements were significant predictors of LNM and prognosis, but variability existed among radiologists and display conditions. AI-based software can provide accurate and reproducible indicators for predicting LNM and prognosis.

Clinical Versus Pathological Staging in Patients with Resected Ground Glass Pulmonary Lesions

BACKGROUND

A ground glass nodule (GGN) is a radiologically descriptive term for a lung parenchymal area with increased attenuation and preserved bronchial and vascular structures. GGNs are further divided into pure versus subsolid lesions. The differential diagnosis for GGNs is wide and contains a malignant possibility for a lung adenocarcinoma precursor or tumor. Clinical and pathological staging of GGNs is based on the lesions' solid component and falls into a specific classification including T0 for TIS, T1mi for minimally invasive adenocarcinoma (MIA) and T1abc for lepidic predominant adenocarcinoma (LPA) according to the eighth edition of the TNM classification of lung cancer. Correlation between solid parts seen on a CT scan and the tumor pathological invasive component is not absolute.

METHODS

This retrospective study collected the data of 68 GGNs that were operated upon in Carmel Medical Center. A comparison between preoperative clinical staging and post-surgery pathological staging was conducted.

RESULTS

Over a third of the lesions, twenty-four (35.3%), were upstaged while only four (5.9%) lesions were downstaged. Another third of the lesions, twenty-three (33.8%), kept their stage. In three (4.4%) cases, premalignant lesion atypical adenomatous hyperplasia (AAH) was diagnosed. Ten (14.7%) cases were diagnosed as non-malignant on final pathology. These findings show an overall low agreement between the clinical and pathological stages of GGNs.

CONCLUSIONS

The relatively high percentage of upstaging tumors detected in this study and the overall safe and short surgical procedure advocate for surgical resection even in the presence of a significant number of non-malignant lesions that retrospectively do not mandate intervention at all.

Pembrolizumab versus sintilimab in patients with advanced NSCLC: a retrospective multicenter study with propensity-score matching analysis

Background

Programmed cell death protein 1 (PD-1) inhibitors are commonly used worldwide for the management of non-small cell lung cancer (NSCLC). However, it remains unclear whether pembrolizumab and sintilimab, two of the most widely used PD-1 inhibitors in China, have significantly different effects on patients with NSCLC. A multicenter retrospective cohort study was designed and implemented using propensity-score matching (PSM) analysis to compare the effectiveness and safety profiles of pembrolizumab and sintilimab in patients with advanced NSCLC undergoing comprehensive therapy.

Methods

A total of 225 patients who received comprehensive therapy including pembrolizumab (n = 127) or sintilimab (n = 98), from 1 January to 31 December 2020 and met the eligibility criteria were included. PSM analysis (1:1) was performed to balance potential baseline confounding factors. For both treatments, Kaplan-Meier analysis and Cox regression were used to compare 1-year progression-free survival (PFS), disease control rate (DCR), objective response rate (ORR), and rates of all adverse events (AEs).

Results

PSM analysis resulted in 63 matched pairs of patients. After PSM, the median PFS was 8.68 months in the sintilimab group and 9.46 months in the pembrolizumab group. The 1-year PFS showed no significant difference between the pembrolizumab and sintilimab groups before and after PSM (P = 0.873 and P = 0.574, respectively). Moreover, within the matched cohort, the pembrolizumab group had an ORR of 30.2% and a DCR of 84.1%, whereas the sintilimab group exhibited an ORR of 41.3% and a DCR of 88.9%. There were no significant differences in the ORR and DCR between the two groups (P = 0.248 and P = 0.629, respectively). The incidence of grade 3 or 4 treatment-related AEs was significantly higher in the pembrolizumab group than that in the sintilimab group (42.9% vs. 33.3%, P = 0.043). Multivariable Cox proportional hazards regression analysis indicated that the lines of treatment and regimens significantly influenced the PFS of patients (P <0.05).

Conclusions

This study demonstrated the similar effectiveness of sintilimab and pembrolizumab in the treatment of patients with advanced NSCLC, with sintilimab potentially displaying a superior clinical safety profile.

Clinical trial registration

https://www.medicalresearch.org.cn/, identifier MR4423000113.

Imaging of Lung Cancer Staging: TNM 9 Updates

Imaging plays a key role in clinical staging of lung cancer and guiding therapy. A thorough understanding of the staging system including the nomenclature and updates is necessary to tailor treatment plans and optimize patient care. The 9th edition of the Tumor, Node, Metastasis staging system for lung cancer has no changes for T classification and subdivides N2 and M1c categories. In nodal staging, N2 splits into N2a, ipsilateral mediastinal single station involvement and N2b, ipsilateral mediastinal multiple stations involvement. In the staging of multiple extrathoracic metastases, M1c splits into M1c1, multiple extrathoracic metastases in one organ system and M1c2, multiple extrathoracic metastases in multiple organ systems. Awareness of the proposed changes in TNM-9 staging classification is essential to provide methodical and accurate imaging interpretation.

Growth and Clinical Impact of Subsolid Lung Nodules ≥6 mm During Long-Term Follow-Up After Five Years of Stability

OBJECTIVE

To investigate the incidence and timing of late growth of subsolid nodules (SSNs) ≥6 mm after initial 5-year stability, its clinical implications, and the appropriate follow-up strategy.

MATERIALS AND METHODS

This retrospective study included SSNs ≥6 mm that remained stable for the initial five years after detection. The incidence and timing of subsequent growth after five years of stability were analyzed using the Kaplan-Meier method. Descriptive analyses were conducted to evaluate the clinical stage shift in the SSNs, showing growth and the presence of metastasis during the follow-up period. Finally, an effective follow-up CT scan strategy for managing SSNs after a 5-year period of stability was investigated.

RESULTS

Two hundred thirty-five eligible SSNs (211 pure ground-glass and 24 part-solid nodules) in 235 patients (median age, 63 years; 132 female) were followed for additional <1 to 181 months (median, 87.0 months; interquartile range [IQR], 47.0-119.0 months) after 5-year stability. Fourteen SSNs (6.0%) showed growth at two to 145 months (median, 96 months; IQR: 43.0-122.25 months) from the CT scan confirming 5-year stability, with the estimated cumulative incidence of growth of 0.4%, 2.1%, and 6.5% at 1, 5, and 10 years, respectively. Nine SSNs (3.8%) exhibited clinical stage shifts. No lung cancer metastases were observed. Hypothetical follow-up CT scans performed at 5, 10, and 15 years after 5-years of stability, would have detected 5 (36%), 11 (79%), and 14 (100%) of the 14 growing SSNs, along with 4 (44%), 8 (89%), and 9 (100%) of the nine stage shifts, respectively.

CONCLUSION

During a long-term follow-up of pulmonary SSNs ≥6 mm after 5-years of stability, a low incidence of growth without occurrence of metastasis was noted. CT scans every five years after the initial 5-year stability period may be reasonable.

Proposed Ninth Edition TNM Staging System for Lung Cancer: Guide for Radiologists

Lung cancer continues to be the primary cause of cancer-related deaths globally. Precise staging is imperative for the development of successful treatment approaches and improvement of patient outcomes. Traditionally, lung cancer staging has depended on the TNM staging system, and the International Association for the Study of Lung Cancer (IASLC) has recently recommended modifications. The updated classification for the ninth edition of the TNM staging system (TNM-9), slated to take effect in January 2025, is derived from a thorough analysis of a newly established large international database of lung cancer cases compiled by the IASLC. Proposed changes in TNM-9 include the following: (a) The mediastinal nodal category (N2) was split into single-station (N2a) and multiple-station (N2b) subcategories, and (b) multiple extrathoracic metastatic lesions (M1c) were split into single organ system (M1c1) and multiple organ systems (M1c2) subcategories. Considering these revisions, adjustments have been made to the established stage groups. In terms of pathologic nodal staging, patients in the post-neoadjuvant ypN category demonstrated worse prognosis than those in the similar non-neoadjuvant pN category. Understanding the fundamental changes introduced in TNM-9 enables radiologists to precisely determine the clinical stage of lung cancer and enhance therapeutic approaches.

Prevalence of invasive lung cancer in pure ground glass nodules less than 30 mm: A systematic review

BACKGROUND

The IASLC TNM proposal suggests that pure ground glass nodules less than 30 mm should be classified as cTis corresponding to pathologic adenocarcinoma in situ implying no invasive malignancy potential. We sought to ascertain the proportion of pure ground glass nodules that harbour tissue confirmed minimally invasive or invasive adenocarcinoma.

METHODS

We analyzed data from 3874 individuals with pure ground glass nodules less than 30 mm, reported in 28 observational studies identified through a systematic search of electronic databases. The primary outcome was the prevalence of invasive malignancy by random effects meta-analysis, and we used meta-regression to determine the impact of baseline risk, size, and country of investigation on overall effect size. The study was registered with PROSPERO (CRD42021286261).

RESULTS

All published studies were retrospective (n = 28) and the majority conducted in Asia (n = 25). Baseline patient cohorts were mainly from published surgical series (n = 22) or lung cancer screening programs (n = 6). The proportion of minimally invasive and invasive cancer ranged from 0.9 % to 100 % with a pooled prevalence of 42.4 % [95 % CI: 0.28, 0.57]. Considerable heterogeneity was observed (I2 =99 %) and patient selection was the most significant contribution, accounting for 73 % of the observed heterogeneity (p < 0.0001). Meta-regression based on size selection and country of investigation revealed no significant contribution to effect size effect or heterogeneity.

CONCLUSIONS

Pure ground glass nodules less than 30 mm harbour a high proportion of invasive malignancy, contrary to the IASLC staging proposals and opinions from numerous guidelines across the world.

Computed tomography characteristics of cN0 primary non-small cell lung cancer predict occult lymph node metastasis

RATIONALE

Occult lymph node metastasis (OLNM) is frequently found in patients with resectable non-small cell lung cancer (NSCLC), despite using diagnostic methods recommended by guidelines.

OBJECTIVES

To evaluate the risk of OLNM in NSCLC patients using the radiologic characteristics of the primary tumor on computed tomography (CT).

METHODS

We retrospectively reviewed clinicopathologic features of 2042 clinical T1-4N0 NSCLC patients undergoing curative intent pulmonary resection. Unique radiological features (i.e., air-bronchogram throughout the whole tumor, heterogeneous ground-glass opacity (GGO), mainly cystic appearance, endobronchial location), percentage of solid portion, and shape of tumor margin were analyzed via a stepwise approach. We used multivariable logistic regression to assess the relationship between OLNM and tumor characteristics.

RESULTS

Compared with the other unique features, endobronchial tumors were associated with the highest risk of OLNM (OR = 3.9, 95% confidence interval (CI) = 2.29-6.62), and heterogeneous GGO and mainly cystic tumors were associated with a low risk of OLNM. For tumors without unique features, the percentage of the solid portion was measured, and solid tumors were associated with OLNM (OR = 2.49, 95% CI = 1.86-3.35). Among part-solid tumors with solid proportion > 50%, spiculated margin, and peri-tumoral GGO were associated with OLNM.

CONCLUSIONS

The risk of OLNM could be assessed using radiologic characteristics on CT. This could allow us to adequately select optimal candidates for invasive nodal staging procedures (INSPs) and complete systematic lymph node dissection.

CLINICAL RELEVANCE STATEMENT

These data may be helpful for clinicians to select appropriate candidates for INSPs and complete surgical systematic lymph node dissection in NSCLC patients.

KEY POINTS

Lymph node metastasis status plays a key role in both prognostication and treatment planning. Solid tumors, particularly endobronchial tumors, were associated with occult lymph node metastasis (OLNM). The risk of OLNM can be assessed using radiologic characteristics acquired from CT images.

Single-cell RNA sequencing reveals immune microenvironment niche transitions during the invasive and metastatic processes of ground-glass nodules and part-solid nodules in lung adenocarcinoma

BACKGROUND

Radiographically, ground-glass nodules (GGN) and part-solid nodules (PSN) in lung adenocarcinoma (LUAD) have significant heterogeneity in their clinical manifestations, biological characteristics, and prognosis. This study aimed to explore the heterogeneity of LUAD in different radiological phenotypes and associated factors influencing tumor evolution.

METHODS

We performed single-cell RNA sequencing (scRNA-seq) on tumor tissues from eight and seven cases of GGN- and PSN-LUAD, respectively, at different disease stages, including minimally invasive adenocarcinoma (MIA), invasive adenocarcinoma (IAC), and metastatic lung cancer (MLC). Additionally, we analyzed adjacent normal tissues from four cases. Immunohistochemistry, multiplex immunofluorescence, and external scRNA-seq data were employed to confirm the expression of signature genes as well as the distribution patterns of CXCL9 + TAMs and TREM2 + TAMs. A LUAD mouse model was generated using gene editing, organoid culture, and orthotopic transplantation techniques, and comprehensive analyses such as histopathology, RNA sequencing, and Western blotting were performed to validate key pathways.

RESULTS

Diverse cellular compositions were observed in the tumor microenvironment (TME) during GGN- and PSN-LUAD invasion and metastasis. Notably, CXCL9 + and TREM2 + tumor-associated macrophages (TAMs) exhibited the most significant enrichment changes. It was found that GGN-LUAD exhibited a stronger immune response than PSN-LUAD, with increased interaction between CXCL9 + TAMs and CD8 + tissue-resident memory T cells during invasion stage (MIA-IAC). Conversely, greater interactions between TREM2 + TAMs and tumor cells were observed in PSN-LUAD during the MLC stage. Additionally, TREM2 + TAMs were found to differentiate into TREM2 + /SPP1 + and TREM2 + /SPP1- TAMs at different stages, which promotes tumor progression. This study also emphasizes that during the transdifferentiation process of GGN- and PSN-LUAD, IFN-γ activates the STAT1 signaling pathway to regulate the activation of CXCL9 + TAMs, and further recruiting CD8 + Trm cells and activating T cells through MHC class I antigen presentation. The role of the IFN-γ/STAT1 pathway in the occurrence and development of LUAD was further validated by animal experiments.

CONCLUSIONS

Our findings offer a potential therapeutic strategy to maintain a dynamic balance within the TME and improve the immunotherapy efficacy by modulating the relative proportions and functional states of CXCL9 + TAMs and TREM2 + TAMs.

A Novel Scale for Diagnosis of Pulmonary Ground-Glass Nodules: A Multicenter and Ambispective Cohort Study

BACKGROUND

A screening tool was devised to aid the diagnosis and treatment of ground-glass nodules (GGNs).

METHODS

The current ambispective cohort study included retrospective collation of 20 variables synthesizing a patient's clinical characteristics, serum tumor markers, and CT results, which allowed division into noninvasive (benign, atypical adenomatous hyperplasia, and adenocarcinoma in situ) and invasive (minimally invasive and invasive adenocarcinomas) tumors to build a prediction nomogram and GGN screening scale. The model was verified internally. A prospective cohort of patients was randomly divided by envelope method into those assessed by the GGN screening scale and those assessed via CT values. The diagnostic efficiencies were compared to allow external verification of the model.

RESULT

A total of 223 patients with 225 GGNs were recruited into the retrospective cohort between January 2021 and December 2022. Multivariable analysis showed sex, diameter, air bronchogram, and vessel convergence sign to be independent factors for prediction of noninvasive and invasive GGNs. Internal verification showed the model had a sensitivity of 70.7% and specificity of 75.0% with the Youden index at 0.457 and area under the curve (AUC) of 0.793 (95% CI: 0.734-0.852). Calibration curves indicated good internal stability (p = 0.357). Between January 2023 and March 2023, 147 patients with 148 GGNs were recruited into the prospective cohort. External verification showed the model had a sensitivity of 92.4% and specificity of 40.0% with the Youden index at 0.324 and AUC of 0.678 (95% CI: 0.509-0.847). Calibration curves indicated good external stability (p = 0.088). The scale was shown to have a sensitivity of 75.00%, specificity of 37.50%, positive predictive value of 91.53%, negative predictive value of 14.29%, and accuracy of 71.25%.

CONCLUSION

The GGN screening scale has high sensitivity and accuracy, making it suitable for diagnosis of GGNs.

Stereologic consequences of iatrogenic collapse: The morphology of adenocarcinoma in situ overlaps with invasive patterns. Proposal for a necessary modified classification of pulmonary adenocarcinomas

Recognizing non-invasive growth patterns is necessary for correct diagnosis, invasive size determination and pT-stage in resected non-small cell lung carcinoma. Due to iatrogenic collapse after resection, the distinction between adenocarcinoma in-situ (AIS) and invasive adenocarcinoma may be difficult. The aim of this study is to investigate the complex morphology of non-mucinous non-invasive patterns of AIS in resection specimen with iatrogenic collapse, and to relate this to follow-up. The effects of iatrogenic collapse on the morphology of collapsed AIS were simulated in a mathematical model. Three dimensional related criteria applied in a modified classification, using also cytokeratin 7 and elastin as additional stains, in two independent retrospective cohorts of primary pulmonary adenocarcinomas ≤3 cm resection specimen with available follow-up information. The model demonstrated that infolding of alveolar walls occurs during iatrogenic collapse and lead to a significant increase in tumor cell heights in maximal collapse areas, compared to less collapsed areas. The morphology of infolded AIS overlaps with patterns described as papillary and acinar adenocarcinoma according to the WHO classification, necessitating an adaptation. The modified classification incorporates recognition of iatrogenic and biologic collapse, tangential cutting effect true invasion and surrogate markers of invasion i.e. grey zone, covering a multilayering falling short of micropapillary, cribriform and solid alveolar filling growth. The use of elastin and CK7 staining aids in the morphologic recognition of iatrogenic collapsed AIS and the distinction from invasive adenocarcinoma. Out of a total of 70 resection specimens 1 case was originally classified as AIS and 9 were reclassified as iatrogenic collapsed AIS. Patients with collapsed AIS showed a 100 % recurrence-free survival after a mean follow-up time of 69.5 months. With the current WHO classification, AIS is overdiagnosed as invasive adenocarcinoma due to infolding. The modified classification facilitates the diagnosis of AIS.

Data-driven risk stratification and precision management of pulmonary nodules detected on chest computed tomography

The widespread implementation of low-dose computed tomography (LDCT) in lung cancer screening has led to the increasing detection of pulmonary nodules. However, precisely evaluating the malignancy risk of pulmonary nodules remains a formidable challenge. Here we propose a triage-driven Chinese Lung Nodules Reporting and Data System (C-Lung-RADS) utilizing a medical checkup cohort of 45,064 cases. The system was operated in a stepwise fashion, initially distinguishing low-, mid-, high- and extremely high-risk nodules based on their size and density. Subsequently, it progressively integrated imaging information, demographic characteristics and follow-up data to pinpoint suspicious malignant nodules and refine the risk scale. The multidimensional system achieved a state-of-the-art performance with an area under the curve (AUC) of 0.918 (95% confidence interval (CI) 0.918-0.919) on the internal testing dataset, outperforming the single-dimensional approach (AUC of 0.881, 95% CI 0.880-0.882). Moreover, C-Lung-RADS exhibited a superior sensitivity compared with Lung-RADS v2022 (87.1% versus 63.3%) in an independent cohort, which was screened using mobile computed tomography scanners to broaden screening accessibility in resource-constrained settings. With its foundation in precise risk stratification and tailored management, this system has minimized unnecessary invasive procedures for low-risk cases and recommended prompt intervention for extremely high-risk nodules to avert diagnostic delays. This approach has the potential to enhance the decision-making paradigm and facilitate a more efficient diagnosis of lung cancer during routine checkups as well as screening scenarios.

Development of a nomogram-based model incorporating radiomic features from follow-up longitudinal lung CT images to distinguish invasive adenocarcinoma from benign lesions: a retrospective study

PURPOSE

To develop and validate a radiomic model for differentiating pulmonary invasive adenocarcinomas from benign lesions based on follow-up longitudinal CT images.

METHODS

This is a retrospective study including 336 patients (161 with invasive adenocarcinomas and 175 with benign lesions) who underwent baseline (T0) and follow-up (T1) CT scans from January 2016 to June 2022. The patients were randomized in a 7:3 ratio into training and test sets. Radiomic features were extracted from lesion volumes of interest on longitudinal CT images at T0 and T1. Differences in radiomic features between T1 and T0 were defined as delta-radiomic features. Logistic regression was used to build models based on clinicoradiological (CR), T0, T1, and delta radiomic features and compute signatures. Finally, a nomogram based on the CR, T0, T1 and delta signatures was constructed. Model performance was evaluated for calibration, discrimination, and clinical utility.

RESULTS

The T1 radiomic model was superior to the other independent models. In the training set, it had an area under the curve (AUC) of 0.858), superior to the CR model (AUC 0.694), the T0 radiomic model (AUC 0.825), and the delta radiomic model (AUC 0.734). In the test set, it had an AUC of 0.817, again outperforming the CR model (AUC 0.578), the T0 radiomic model (AUC 0.789), and the delta radiomic model (AUC 0.647). The nomogram incorporating the CR, T0, T1 and delta signatures showed the best predictive performance in both the training (AUC: 0.906) and test sets (AUC: 0.856), and it exhibited excellent fit with calibration curves. Decision curve analysis provided additional validation of the clinical utility of the nomogram.

CONCLUSION

A nomogram utilizing radiomic features extracted from longitudinal CT images can enhance the discriminative capability between pulmonary invasive adenocarcinomas and benign lesions.

Prognostic factors for resected invasive mucinous lung adenocarcinoma: a systematic review and meta-analysis

BACKGROUND

Surgery is the optimal choice for early invasive mucinous lung adenocarcinoma (IMA). A systematic review and meta-analysis were conducted to explore the prognostic factors for resected IMA.

METHODS

We systematically reviewed the prognostic role of clinicopathological and genomic factors in resected IMA patients. Eligible studies on the treatment of IMA following the systematic search of PubMed, Embase and the Cochrane Library from January 2015 to January 2024 were identified. Outcomes of interest were overall survival (OS) and disease-free survival/recurrence-free survival (DFS/RFS). The hazard ratio (HR) and 95% confidence interval (CI) were used as impact indicators for systematic review and meta-analysis.

RESULTS

Sixteen studies involving 3,484 patients with IMA were included. The results of the combined analysis showed that male and smoking were associated with a worse prognosis. Furthermore, advanced clinical stage, poor differentiation grade, presence of visceral pleural invasion (VPI) and spread through air spaces (STAS), and presence of KRAS mutations were also associated with worse prognosis.

CONCLUSIONS

Gender, smoking, clinical stage, tumor size, differentiation grading, VPI, STAS and KRAS mutation affect DFS/RFS and OS of IMA patients after surgery. Identifying these factors may aid physicians in developing more individualized treatment plans for resectable IMA patients.

Predicting Recurrence after Sublobar Resection in Patients with Lung Adenocarcinoma Using Preoperative Chest CT Scans

Background Sublobar resection for lung cancer is usually guided by cutoff values for consolidation size (maximal diameter of the solid tumor component) and consolidation-to-tumor ratio (CTR). The effects of these factors as continuous variables and the reason for established cutoffs are, to the knowledge of the authors, unexplored. Purpose To quantitatively assess the predictive value of CTR and consolidation size for cancer recurrence risk after sublobar resection in clinical stage IA lung adenocarcinoma. Materials and Methods This retrospective study reviewed sublobar resection for clinical stage IA lung adenocarcinoma performed between January 2010 and December 2019. A restricted cubic spline function verified linearity by estimating recurrence probabilities using CTR and consolidation size obtained on preoperative CT scans. Statistical analyses included a Cox proportional hazards model to identify risk factors for cancer recurrence and the Cochran-Armitage trend test for the association between CTR and consolidation size. Results Of 1032 enrolled patients (age, 63.9 years ± 9.9 [SD]; 464 male patients), 523 (50.7%) and 509 (49.3%) underwent wedge resection and segmentectomy, respectively. Among patients with a CTR between 1% and 50% (n = 201), 187 (93.0%) had a consolidation size of less than or equal to 10 mm (P < .001). There was a positive association between the risk of recurrence with CTR and consolidation size (r2 = 0.727; P < .001). The recurrence rate showed the greatest increase when CTR was greater than 50% or consolidation size was greater than 10 mm. Specifically, the recurrence rate increased from 2.1% (three of 146) at 26%-50% CTR to 8.3% (nine of 108) at 51%-75% CTR, and from 4.4% (eight of 183) for 6-10-mm consolidation size to 11.9% (23 of 194) for 11-15-mm consolidation size. The probability of recurrence exhibited linearity and increased with CTR and consolidation size. Conclusion Cancer recurrence risk after sublobar resection for stage IA adenocarcinoma consistently rises with CTR and consolidation size. Current guideline cutoffs for sublobar resection remain clinically relevant given observed recurrence rates. © RSNA, 2024 Supplemental material is available for this article.

Comparative analysis of three-dimensional and two-dimensional models for predicting the malignancy probability of subsolid nodules

AIM

To construct three-dimensional (3D) and two-dimensional (2D) models to predict the malignancy probability of subsolid nodules (SSNs) and compare their effectiveness.

MATERIALS AND METHODS

A total of 371 SSNs from 332 patients, collected between January 2020 and January 2024, were included in the study. The SSNs were divided into a training set for constructing the models and a test set for validating the models. Models were developed using binary logistic backward regression, based on factors that showed significant differences in univariate analyses. The performance of the models was assessed using the area under the curve (AUC) of the receiver operating characteristic (ROC). The AUCs of different models were compared using the DeLong test.

RESULTS

The AUCs for the two 3D models, one 2D model, and the Brock model were 0.785 (0.733-0.836), 0.776 (0.723-0.829), 0.764 (0.710-0.818), and 0.738 (0.679-0.798) in the training set. In the test set, these AUCs were 0.817 (0.706-0.928), 0.796 (0.679-0.913), 0.771 (0.647-0.895), and 0.790 (0.678-0.903). The two 3D models demonstrated statistically significant differences from the Brock model in the training set (P=0.024 and P=0.046). None of the four models showed significant differences in the test set (all P>0.05).

CONCLUSION

The 3D models outperform both the 2D model and the Brock model in predicting the malignancy probability of SSNs, and the 3D model incorporating volume, mean CT attenuation value, and lobulation as factors performed the best.

A retrospective analysis of simultaneous bilateral uniportal thoracoscopic surgeries for multiple primary bilateral pulmonary nodules

BACKGROUND

There are no standard treatment options for bilateral multiple pulmonary nodules requiring resection. This study aimed to summarize the experience of simultaneous bilateral uniportal video-assisted thoracoscopic surgery for the treatment of bilateral multiple primary pulmonary nodules.

METHODS

The clinical data of 65 cases of simultaneous bilateral uniportal thoracoscopic surgery for bilateral multiple primary pulmonary nodules treated were retrospectively analyzed. These cases were treated within The Ninth Medical Center of PLA General Hospital between January 2018 and November 2020. Parameters related to the surgery, perioperative aspects, surgical techniques, pathology results, and postoperative complications were examined.

RESULTS

All surgeries were conducted through uniportal video-assisted thoracoscopic surgery, with no instances of intraoperative conversion to thoracotomy. Fifty-three patients further underwent CT-guided Hookwire localization for the localization of pulmonary nodules. A total of 189 nodules were resected using multiple surgical procedures, with a malignancy rate of 86.2%. The average operation time was 226 ± 77.4 min, the average thoracic drainage duration was 3.1 ± 1.5 days, the average 24 h pleural drainage was 385.9 ± 157.4 mL, the average postoperative hospital stay was 8.6 ± 2.4 days, and the average blood loss was 77.2 ± 33.8 mL. Post-surgery, all patients were transferred to the ward safely within 12 h. 15.38% of patients have prolonged drainage time, and 12.31% of patients experience complications such as lung infection, arrhythmia, and venous thrombosis.

CONCLUSION

The selected cases undergoing simultaneous bilateral uniportal video-assisted thoracoscopic surgery for the management of bilateral multiple primary pulmonary nodules demonstrated favorable outcomes. Our observations indicate the safety and feasibility of this procedure, providing an individualized and precise treatment approach for affected patients.

The Proposed Ninth Edition TNM Classification of Lung Cancer

A universal nomenclature of the anatomic extent of lung cancer has been critical for individual patient care as well as research advances. As progress occurs, new details emerge that need to be included in a refined system that aligns with contemporary clinical management issues. The ninth edition TNM classification of lung cancer, which is scheduled to take effect in January 2025, addresses this need. It is based on a large international database, multidisciplinary input, and extensive statistical analyses. Key features of the ninth edition include validation of the significant changes in the T component introduced in the eighth edition, subdivision of N2 after exploration of fundamentally different ways of categorizing the N component, and further subdivision of the M component. This has led to reordering of the TNM combinations included in stage groups, primarily involving stage groups IIA, IIB, IIIA, and IIIB. This article summarizes the analyses and revisions for the TNM classification of lung cancer to familiarize the broader medical community and facilitate implementation of the ninth edition system.

Knowledge mapping analysis of ground glass nodules: a bibliometric analysis from 2013 to 2023

Background

In recent years, the widespread use of computed tomography (CT) in early lung cancer screening has led to an increase in the detection rate of lung ground glass nodules (GGNs). The persistence of GGNs, which may indicate early lung adenocarcinoma, has been a focus of attention for scholars in the field of lung cancer prevention and treatment in recent years. Despite the rapid development of research into GGNs, there is a lack of intuitive content and trend analyses in this field, as well as a lack of detailed elaboration on possible research hotspots. The objective of this study was to conduct a comprehensive analysis of the knowledge structure and research hotspots of lung ground glass nodules over the past decade, employing bibliometric methods.

Method

The Web of Science Core Collection (WoSCC) database was searched for relevant ground-glass lung nodule literature published from 2013-2023. Bibliometric analyses were performed using VOSviewer, CiteSpace, and the R package "bibliometrix".

Results

A total of 2,218 articles from 75 countries and 2,274 institutions were included in this study. The number of publications related to GGNs has been high in recent years. The United States has led in GGNs-related research. Radiology has one of the highest visibilities as a selected journal and co-cited journal. Jin Mo Goo has published the most articles. Travis WD has been cited the most frequently. The main topics of research in this field are Lung Cancer, CT, and Deep Learning, which have been identified as long-term research hotspots. The GGNs-related marker is a major research trend in this field.

Conclusion

This study represents the inaugural bibliometric analysis of applied research on ground-glass lung nodules utilizing three established bibliometric software. The bibliometric analysis of this study elucidates the prevailing research themes and trends in the field of GGNs over the past decade. It also furnishes pertinent recommendations for researchers to provide objective descriptions and comprehensive guidance for future related research.

Establishment of artificial intelligence model for precise histological subtyping of lung adenocarcinoma and its application to quantitative and spatial analysis

BACKGROUND

The histological subtype of lung adenocarcinoma is a major prognostic factor. We developed a new artificial intelligence model to classify lung adenocarcinoma images into seven histological subtypes and adopted the model for whole-slide images to investigate the relationship between the distribution of histological subtypes and clinicopathological factors.

METHODS

Using histological subtype images, which are typical for pathologists, we trained and validated an artificial intelligence model. Then, the model was applied to whole-slide images of resected lung adenocarcinoma specimens from 147 cases.

RESULT

The model achieved an accuracy of 99.7% in training sets and 90.4% in validation sets consisting of typical tiles of histological subtyping for pathologists. When the model was applied to whole-slide images, the predominant subtype according to the artificial intelligence model classification matched that determined by pathologists in 75.5% of cases. The predominant subtype and tumor grade (using the WHO fourth and fifth classifications) determined by the artificial intelligence model resulted in similar recurrence-free survival curves to those determined by pathologists. Furthermore, we stratified the recurrence-free survival curves for patients with different proportions of high-grade components (solid, micropapillary and cribriform) according to the physical distribution of the high-grade component. The results suggested that tumors with centrally located high-grade components had a higher malignant potential (P < 0.001 for 5-20% high-grade component).

CONCLUSION

The new artificial intelligence model for histological subtyping of lung adenocarcinoma achieved high accuracy, and subtype quantification and subtype distribution analyses could be achieved. Artificial intelligence model therefore has potential for clinical application for both quantification and spatial analysis.

The 2023 American Association for Thoracic Surgery (AATS) Expert Consensus Document: Management of subsolid lung nodules

OBJECTIVE

Lung cancers that present as radiographic subsolid nodules represent a subtype with distinct biological behavior and outcomes. The objective of this document is to review the existing literature and report consensus among a group of multidisciplinary experts, providing specific recommendations for the clinical management of subsolid nodules.

METHODS

The American Association for Thoracic Surgery Clinical Practice Standards Committee assembled an international, multidisciplinary expert panel composed of radiologists, pulmonologists, and thoracic surgeons with established expertise in the management of subsolid nodules. A focused literature review was performed with the assistance of a medical librarian. Expert consensus statements were developed with class of recommendation and level of evidence for each of 4 main topics: (1) definitions of subsolid nodules (radiology and pathology), (2) surveillance and diagnosis, (3) surgical interventions, and (4) management of multiple subsolid nodules. Using a modified Delphi method, the statements were evaluated and refined by the entire panel.

RESULTS

Consensus was reached on 17 recommendations. These consensus statements reflect updated insights on subsolid nodule management based on the latest literature and current clinical experience, focusing on the correlation between radiologic findings and pathological classifications, individualized subsolid nodule surveillance and surgical strategies, and multimodality therapies for multiple subsolid lung nodules.

CONCLUSIONS

Despite the complex nature of the decision-making process in the management of subsolid nodules, consensus on several key recommendations was achieved by this American Association for Thoracic Surgery expert panel. These recommendations, based on evidence and a modified Delphi method, provide guidance for thoracic surgeons and other medical professionals who care for patients with subsolid nodules.

Clinical Significance of SIRPα Expression on Tumor-Associated Macrophages in Patients with Lung Squamous Cell Carcinoma

BACKGROUND

Signal-regulatory protein alpha (SIRPα) is an immune checkpoint molecule expressed on macrophages that functions to inhibit phagocytosis by binding to CD47 expressed on tumor cells. SIRPα has attracted increasing attention as a novel target for cancer immunotherapy; however, the expression and immune function of SIRPα in lung squamous cell carcinoma (LUSC) remain unclear. Therefore, this study aimed to identify the clinical importance of SIRPα expression in LUSC and to explore the factors that elevate SIRPα expression.

PATIENTS AND METHODS

Primary LUSC specimens surgically resected from 172 patients underwent immunohistochemical evaluation of the association of SIRPα expression on tumor-associated macrophages with clinicopathological features and clinical outcomes. Furthermore, we analyzed the association of SIRPα expression with tumor-infiltrating lymphocytes and the expression of programmed cell death ligand 1 (PD-L1). In vitro, monocytes were treated with cytokines, and SIRPα protein expression was assessed by flow cytometry.

RESULTS

There were no differences in SIRPα expression and clinicopathological factors. High SIRPα expression was significantly associated with PD-L1-positive expression, and high CD8, PD-1, and CD163 expression. The high SIRPα expression group showed significantly shorter recurrence-free survival (RFS) and overall survival (OS). On multivariate analysis, high SIRPα expression was an independent poor prognostic factor for RFS and OS. The expression of SIRPα protein in monocytes was upregulated by treatment with IFNγ.

CONCLUSION

Our analysis revealed that high SIRPα expression significantly predicts poor prognosis in patients with surgically resected LUSC.

Clinical characteristics and prognosis of non-high-risk patients with incidental stage T1 lung cancer: A prospective cohort study

OBJECTIVES

There is currently no evidence documenting the clinical characteristics and prognosis of non-high-risk patients with incidental stage T1 lung cancer (LC). The aim of this study was to investigate the clinical characteristics and prognosis of non-high-risk patients with incidental stage T1 LC.

METHODS

This prospective cohort study included patients with incidental stage T1 LC who were diagnosed pathologically at the First Affiliated Hospital of Chongqing Medical University between 1st Jan 2019 and 31st Dec 2023. The follow-up time for all participants concluded on 31st Jan 2024, or upon death. All included patients were divided into non-high-risk (observation) and high-risk (control) groups based on the 2021 US preventative services task force recommendations. The primary outcomes were overall survival probability and LC-specific survival probability. The secondary outcomes were clinical characteristics, including demographic variables, histological types and TNM staging.

RESULTS

We studied 1876 patients with incidental stage T1 LC. Of these, 1491 (79.48%) non-high-risk patients were included in the observation group, and the remaining 385 (20.52%) high-risk patients composed the control group. The follow-up interval was between 0 and 248 months for all participants, with a median time of 41.64 ± 23.85 months. The patients in the observation group were younger and had smaller tumors, more adenocarcinomas, and earlier disease stages than those in the control group (p ≤ 0.001). The overall survival probability (HR = 0.23, [95% CI: 0.18, 0.31], p < 0.001) and the LC-specific survival probability (HR = 0.23, [95% CI: 0.17, 0.31], p < 0.001) for the patients in the observation group were also both higher than those in the control group. The results appeared to be consistent across important subgroups.

CONCLUSION

In this study, non-high-risk patients with incidental stage T1 LC were younger, had smaller tumors, had more adenocarcinomas, had a lower probability of metastasis, and had longer survival than did high-risk patients.

The Overlooked Cornerstone in Precise Medicine: Personalized Postoperative Surveillance Plan for NSCLC

Non-small cell lung cancer recurrence after curative-intent surgery remains a challenge despite advancements in treatment. We review postoperative surveillance strategies and their impact on overall survival, highlighting recommendations from clinical guidelines and controversies. Studies suggest no clear benefit from more intensive imaging, whereas computed tomography scans reveal promise in detecting recurrence. For early-stage disease, including ground-glass opacities and adenocarcinoma in situ or minimally invasive adenocarcinoma, less frequent surveillance may suffice owing to favorable prognosis. Liquid biopsy, especially circulating tumor deoxyribonucleic acid, holds potential for detecting minimal residual disease. Clinicopathologic factors and genomic profiles can also provide information about site-specific metastases. Machine learning may enable personalized surveillance plans on the basis of multi-omics data. Although precision medicine transforms non-small cell lung cancer treatment, optimizing surveillance strategies remains essential. Tailored surveillance strategies and emerging technologies may enhance early detection and improve patients' survival, necessitating further research for evidence-based protocols.

Minor (≤ 10%) Ground-Glass Opacity Component in Clinical Stage I Non-Small Cell Lung Cancer: Associations With Pathologic Characteristics and Clinical Outcomes

BACKGROUND. The presence of a ground-glass opacity (GGO) component is a favorable prognostic factor in non-small cell lung cancer (NSCLC), although the prognostic impact of a very small GGO component remains poorly investigated. OBJECTIVE. The purpose of this article is to investigate the impact of a minor (≤ 10%) GGO component on the prognosis of clinical stage I NSCLC in comparison with pure-solid nodules. METHODS. This retrospective study included 382 patients (mean age, 60.8 years; 210 men, 172 women) who underwent surgical resection between January 1, 2015, and December 31, 2015, for clinical stage I NSCLC appearing on preoperative chest CT as a nodule with a consolidation-to-tumor ratio (CTR) of 0.9 to 1.0. Two radiologists independently assigned nodules to groups as either minor GGO (CTR, ≥ 0.9 and < 1.0) or pure solid (CTR = 1.0). Recurrence-free survival (RFS) and cancer-specific survival (CSS) were assessed by Kaplan-Meier curves and compared between groups using log-rank tests. Cox proportional hazards models were used to assess associations with outcomes. RESULTS. The two radiologists agreed for all nodules' classification into the minor-GGO (n = 106) or pure-solid (n = 276) groups. The mean CTR of the minor-GGO group was 0.93 ± 0.02 (SD) (range, 0.90-0.97). Minor-GGO nodules, in comparison with pure-solid nodules, showed greater solid-component diameter (2.68 vs 2.16 cm; p < .001) and total nodule diameter (2.89 vs 2.16 cm; p < .001). The minor-GGO group, in comparison with the pure-solid group, showed lower frequencies of visceral pleural invasion (6.6% vs 17.0%, p = .009) and pathologic lymph node involvement (4.7% vs 20.3%, p < .001), and EGFR mutation (71.6% vs 39.9%; p < .001). The minor-GGO group, in comparison with the pure-solid group, showed better 5-year RFS (83.4% vs 55.0%; p < .001) and higher frequency of better 5-year CSS (92.4% vs 76.4%, p = .004). In multivariable analysis adjusting for patient, imaging, pathologic, and genetic factors, a minor-GGO component was independently associated with a decreased likelihood of recurrence (HR = 0.37, p = .001) but not with the likelihood of CSS. CONCLUSION. Among patients with clinical stage I NSCLC, cancers with a minor-GGO component were associated with a better prognosis versus those with a pure-solid appearance. CLINICAL IMPACT. Radiologists encountering predominantly solid nodules on CT should carefully assess images for even a minor-GGO component given the favorable prognosis.

A retrospective analysis of treatment patterns, overall survival, and real-world disease-free survival in early-stage non-small cell lung cancer following complete resection

BACKGROUND

Real-world data regarding patient characteristics, adjuvant treatment patterns, and long-term survival outcomes are needed to better understand unmet needs among patients with completely resected early-stage non-small cell lung cancer (NSCLC).

METHODS

Electronic medical records from the U.S.-based ConcertAI Patient360™ database were analyzed in patients with stage IB-IIIA NSCLC who underwent complete resection prior to March 1, 2016. Patients were followed until death or July 1, 2021. This study evaluated adjuvant chemotherapy use, and overall survival (OS) and real-world disease-free survival (rwDFS) outcomes using the Kaplan-Meier method. The correlation between OS and rwDFS was assessed using the Kendall rank test. Among patients who did not recur 5 years following surgery, landmark analyses of OS and rwDFS were conducted to understand the subsequent survival impact of remaining disease-free for at least 5 years.

RESULTS

Data from 441 patients with completely resected stage IB-IIIA NSCLC were included. About 35% of patients received adjuvant chemotherapy post-resection. Median OS and rwDFS from resection were 83.1 months and 42.4 months, respectively. The 5-year OS and rwDFS rates were 65.7% and 42.1%, respectively. OS and rwDFS were positively correlated (Kendall rank correlation coefficient = 0.67; p < 0.0001). Among patients without recurrence within 5 years after resection, the subsequent 5-year OS and rwDFS survival rates were 52.9% and 36.6%, respectively.

CONCLUSIONS

Use of adjuvant chemotherapy was low, and the overall 5-year OS rate remained low despite all patients having undergone complete resection. Patients who remained non-recurrent over time had favorable subsequent long-term survival.

Long-term outcomes and risk factors for recurrence after lung segmentectomy

OBJECTIVES

The long-term oncological outcomes and risk factors for recurrence after lung segmentectomy are unclear. The aims of this study were to investigate the long-term prognosis and to evaluate risk factors for recurrence after segmentectomy.

METHODS

Between January 2008 and December 2012, a total of 177 patients underwent segmentectomy for clinical stage I non-small cell lung cancer. The median follow-up period was 120.1 months. The overall survival (OS) and recurrence-free survival curves were analysed using the Kaplan-Meier method with a log-rank test. Univariable and multivariable analyses were used to identify significant factors that predicted recurrence.

RESULTS

The study included 177 patients with a median age of 67 years. The median operative time was 155 min. No 30-day deaths were observed. Nine patients (5.1%) had recurrences: loco-regional in 3, distant in 3 and both in 3. The 5-year and 10-year recurrence-free survival rates were 89.7% and 79.8%, and the OS rates were 90.9% and 80.4%, respectively. On multivariable analysis, the risk factor associated with recurrence was a pure solid tumour [hazard ratio, 23.151; 95% confidence interval 2.575-208.178; P = 0.005]. The non-pure solid tumour group had a significantly better probability of survival (5-year OS: 95.4% vs 77.2%; 10-year OS: 86.5% vs 61.8%; P < 0.0001). A total of 113 patients received preoperative positron emission tomography/computed tomography. Patients with a higher maximum standardized uptake value had a significantly higher recurrence rate.

CONCLUSIONS

Segmentectomy for clinical stage I non-small cell lung cancer produced acceptable long-term outcomes. Pure solid radiographic appearance was associated with recurrence and decreased survival.