Factors influencing the concordance of histological subtype diagnosis from biopsy and resected specimens of lung adenocarcinoma

Role of Epiregulin in Lung Tumorigenesis and Therapeutic Resistance

Epidermal growth factor (EGF) signaling regulates multiple cellular processes and plays an essential role in tumorigenesis. Epiregulin (EREG), a member of the EGF family, binds to the epidermal growth factor receptor (EGFR) and ErbB4, and it stimulates EGFR-related downstream pathways. Increasing evidence indicates that both the aberrant expression and oncogenic function of EREG play pivotal roles in tumor development in many human cancers, including non-small cell lung cancer (NSCLC). EREG overexpression is induced by activating mutations in the EGFR, KRAS, and BRAF and contributes to the aggressive phenotypes of NSCLC with oncogenic drivers. Recent studies have elucidated the roles of EREG in a tumor microenvironment, including the epithelial-mesenchymal transition, angiogenesis, immune evasion, and resistance to anticancer therapy. In this review, we summarized the current understanding of EREG as an oncogene and discussed its oncogenic role in lung tumorigenesis and therapeutic resistance.

Preoperative 18F-FDG PET/CT and CT radiomics for identifying aggressive histopathological subtypes in early stage lung adenocarcinoma

Lung adenocarcinoma (ADC) is the most common non-small cell lung cancer. Surgical resection is the primary treatment for early-stage lung ADC while lung-sparing surgery is an alternative for non-aggressive cases. Identifying histopathologic subtypes before surgery helps determine the optimal surgical approach. Predominantly solid or micropapillary (MIP) subtypes are aggressive and associated with a higher likelihood of recurrence and metastasis and lower survival rates. This study aims to non-invasively identify these aggressive subtypes using preoperative 18F-FDG PET/CT and diagnostic CT radiomics analysis. We retrospectively studied 119 patients with stage I lung ADC and tumors ≤ 2 cm, where 23 had aggressive subtypes (18 solid and 5 MIPs). Out of 214 radiomic features from the PET/CT and CT scans and 14 clinical parameters, 78 significant features (3 CT and 75 PET features) were identified through univariate analysis and hierarchical clustering with minimized feature collinearity. A combination of Support Vector Machine classifier and Least Absolute Shrinkage and Selection Operator built predictive models. Ten iterations of 10-fold cross-validation (10 ×10-fold CV) evaluated the model. A pair of texture feature (PET GLCM Correlation) and shape feature (CT Sphericity) emerged as the best predictor. The radiomics model significantly outperformed the conventional predictor SUVmax (accuracy: 83.5% vs. 74.7%, p = 9e-9) and identified aggressive subtypes by evaluating FDG uptake in the tumor and tumor shape. It also demonstrated a high negative predictive value of 95.6% compared to SUVmax (88.2%, p = 2e-10). The proposed radiomics approach could reduce unnecessary extensive surgeries for non-aggressive subtype patients, improving surgical decision-making for early-stage lung ADC patients.

Efficacy of Preoperative Biopsy in Predicting the Newly Proposed Histologic Grade of Resected Lung Adenocarcinoma

A novel histologic grading system for invasive lung adenocarcinomas (LUAD) has been newly proposed and adopted by the World Health Organization (WHO) classification. We aimed to evaluate the concordance of newly established grades between preoperative biopsy and surgically resected LUAD samples. Additionally, factors affecting the concordance rate and its prognostic impact were also analyzed. In this study, surgically resected specimens of 222 patients with invasive LUAD and their preoperative biopsies collected between January 2013 and December 2020 were used. We determined the histologic subtypes of preoperative biopsy and surgically resected specimens and classified them separately according to the novel WHO grading system. The overall concordance rate of the novel WHO grades between preoperative biopsy and surgically resected samples was 81.5%, which was higher than that of the predominant subtype. When stratified by grades, the concordance rate of grades 1 (well-differentiated, 84.2%) and 3 (poorly differentiated, 89.1%) was found to be superior compared to grade 2 (moderately differentiated, 66.2%). Overall, the concordance rate was not significantly different from biopsy characteristics, including the number of biopsy samples, biopsy sample size, and tumor area size. On the other hand, the concordance rate of grades 1 and 2 was significantly higher in tumors with smaller invasive diameters, and that of grade 3 was significantly higher in tumors with larger invasive diameters. Preoperative biopsy specimens can predict the novel WHO grades, especially grades 1 and 3 of surgically resected specimens, more accurately than the former grading system, regardless of preoperative biopsy or clinicopathologic characteristics.

Diagnostic efficacy of cryobiopsy for peripheral pulmonary lesions: A propensity score analysis

OBJECTIVES

Recently introduced cryobiopsy can provide quantitatively and qualitatively excellent specimens. However, few studies have directly compared the diagnostic yield of cryobiopsy for peripheral pulmonary lesions (PPLs) with that of conventional sampling methods.

MATERIAL AND METHODS

We retrospectively reviewed data from consecutive patients who underwent diagnostic bronchoscopy using radial endobronchial ultrasound and virtual bronchoscopic navigation for PPLs (October 2015 to September 2020). Patients who underwent cryobiopsy were assigned to the cryo group, whereas those who did not undergo cryobiopsy were assigned to the conventional group. The diagnostic outcomes of both groups were compared using propensity score analyses.

RESULTS

A total of 2,724 cases were identified, including 492 and 2,232 cases in the cryo and conventional groups, respectively. Propensity scoring was performed to match baseline characteristics, and 481 pairs of cases were selected for each matched group (m-group). The diagnostic yield was significantly higher in the m-cryo group than in the m-conventional group (89.2% vs. 77.6%, odds ratio [OR] = 2.36 [95% confidence interval [CI] = 1.65-3.38], P < 0.001). Propensity score stratification (OR = 2.35 [95% CI = 1.71-3.23]) and regression adjustment (OR = 2.54 [95% CI = 1.83-3.52]) also demonstrated the diagnostic advantages of cryobiopsy. The subgroup analysis revealed that cryobiopsy was notably effective for lesions in the middle lobe/lingula, right/left lower lobe, lesions with ground-glass opacity, and lesions invisible on chest radiography. Although there were more cases of grade 2 and 3 bleeding in the m-cryo group than in the m-conventional group (38.0% vs. 10.2% and 1.5% vs. 0.8%, respectively; P < 0.001), no grade 4 bleeding was observed.

CONCLUSION

The propensity score analyses revealed that cryobiopsy was associated with a higher diagnostic yield for PPLs than conventional sampling methods. However, increased bleeding risk should be noted as a potential complication.

The prognostic value of histopathology in invasive lung adenocarcinoma: a comparative review of the main proposed grading systems

INTRODUCTION

An accurate histological evaluation of invasive lung adenocarcinoma is essential for a correct clinical and pathological definition of the tumour. Different grading systems have been proposed to predict the prognosis of invasive lung adenocarcinoma.

AREAS COVERED

Invasive non mucinous lung adenocarcinoma is often morphologically heterogeneous, consisting of complex combinations of architectural patterns with different proportions. Several grading systems for non-mucinous lung adenocarcinoma have been proposed, being the main based on architectural differentiation and the predominant growth pattern. Herein we perform a thorough review of the literature using PubMed, Scopus and Web of Science and we highlight the peculiarities and the differences between the main grading systems and compare the data about their prognostic value. In addition, we carried out an evaluation of the proposed grading systems for less common histological variants of lung adenocarcinoma, such as fetal adenocarcinoma and invasive mucinous adenocarcinoma.

EXPERT OPINION

The current IASLC grading system, based on the combined score of predominant growth pattern plus high-grade histological pattern, shows the stronger prognostic significance than the previous grading systems in invasive non mucinous lung adenocarcinoma.

Comparison of small biopsy and cytology specimens: Subtyping of pulmonary adenocarcinoma

Objectives

The aims of this study was to investigate the use of cytologic samples for subclassification of lung adenocarcinoma and the cytologic-histologic correlation in lung adenocarcinoma subtypes using small samples.

Methods and Methods

Cytological characteristics of lung adenocarcinoma subtypes were summarized by a literature review. Cytology samples from 115 patients with lung adenocarcinoma confirmed by small biopsies were classified by subtype. The diagnostic concordance of subtypes between biopsy and cytology samples was assessed.

Results

Among the 115 cases, 62 (53.9%) had acinar predominant pattern, 16 (13.9%) were papillary predominant pattern, 29 (25.2%) had solid predominant pattern, 3 (2.6%) had lepidic predominant pattern, and 5 (4.3%) had micropapillary predominant pattern. All corresponding cytologic samples were classified into five subtypes based on cytomorphology features, with concordance rates of 74.2% (46 patients) in c-acinar subtype, 56.3% (nine patients) in c-papillary subtype, 24.1% (seven patients) in c-solid subtype, 66.7% (two patients) in c-lepidic subtype, and 40% (two patients) in c-micropapillary subtype. Collectively, the cytology and small biopsy concordance rate was approximately 57.4%.

Conclusion

Subtyping of lung adenocarcinoma using cytologic specimens is challenging and the consistency rate varies with the subtype. Acinar predominant tumors have an excellent cytologic-histologic correlation compared to tumors with predominant solid or micropapillary pattern. Evaluating cytomorphologic features of different lung adenocarcinoma subtypes can reduce the false-negative rate of lung adenocarcinoma, particularly for the mild, atypical micropapillary subtype, and improve diagnostic accuracy.

The value of prognostic and predictive parameters in early-stage lung adenocarcinomas: A comparison between biopsies and resections

INTRODUCTION

Since lung adenocarcinoma (LUAD) biopsies are usually small, it is questionable if their prognostic and predictive information is comparable to what is offered by large resection specimens. This study compares LUAD biopsies and resection specimens for their ability to provide prognostic and predictive parameters.

METHODS

We selected 187 biopsy specimens with stage I and II LUAD. In 123 cases, subsequent resection specimens were also available. All specimens were evaluated for growth pattern, nuclear grade, fibrosis, inflammation, and genomic alterations. Findings were compared using non-parametric testing for categorical variables. Model performance was assessed using the area under the curve for both biopsies and resection specimens, and overall (OS) and disease-free survival (DFS) was calculated.

RESULTS

The overall growth pattern concordance between biopsies and resections was 73.9%. The dominant growth pattern correlated with OS and DFS in resected adenocarcinomas and for high-grade growth pattern in biopsies. Multivariate analysis of biopsy specimens revealed that T2-tumors, N1-status, KRAS mutations and a lack of other driver mutations were associated with poorer survival. Model performance using clinical, histological and genetic data from biopsy specimens for predicting OS and DSF demonstrated an AUC of 0.72 and 0.69, respectively.

CONCLUSIONS

Our data demonstrated the prognostic relevance of a high-grade growth pattern in biopsy specimens of LUAD. Combining clinical, histological and genetic information in one model demonstrated a suboptimal performance for DFS prediction and good performance for OS prediction. However, for daily practice, more robust (bio)markers are required to predict prognosis and stratify patients for therapy and follow-up.

Validation of the novel International Association for the Study of Lung Cancer grading system and prognostic value of filigree micropapillary and discohesive growth pattern in invasive pulmonary adenocarcinoma

INTRODUCTION

The Pathology Committee of the International Association for the Study of Lung Cancer (IASLC) proposed a new histological grading system based on the combination of predominant and high-grade patterns in 2020.

MATERIALS AND METHODS

Pathological sections from 631 patients with stage I-III invasive lung adenocarcinoma were reviewed. We then determined the histological grade according to the new grading system and confirmed the pathological features that included the filigree micropapillary and discohesive growth pattern. Applying of the novel IASLC grading system in prognosis stratification was verified and the clinical significance of the pathological characteristics was explored.

RESULTS

Cox multivariable analysis revealed that in the stage I-III invasive lung adenocarcinoma, the IASLC grading system was significantly associated with disease-free survival (DFS) [hazard ratio (HR) = 1.419; 95 % confidence interval (CI): 1.040-1.937; P = 0.027] and overall survival (OS) (HR = 1.899; 95 % CI: 1.168-3.087; P = 0.010). In patients with IASLC Grades 1 and 2, the simultaneous presence of filigree micropapillary and discohesive growth pattern was significantly correlated with DFS (HR = 1.899; 95 % CI:1.168-3.087; P = 0.010). However, the filigree micropapillary and discohesive growth pattern did not affect the OS (HR = 2.786; P = 0.317). The competitive risk model revealed that in the stage I cohort, the simultaneous presence of filigree micropapillary and discohesive growth pattern was a risk factor for recurrence and metastasis [sub- distribution HR (SHR) = 1.987; 95 %CI: 1.122-3.518; P = 0.019].

CONCLUSION

Our study verified that the new prognostic stratification system was an effective stratification tool. Filigree micropapillary and discohesive growth pattern may also be risk factors for DFS, postoperative recurrence and metastasis.

Predictors of Invasiveness in Adenocarcinoma of Lung with Lepidic Growth Pattern

Lung adenocarcinoma with lepidic growth pattern (LPA) is characterized by tumor cell proliferation along intact alveolar walls, and further classified as adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) and invasive lepidic predominant adenocarcinoma (iLPA). Accurate diagnosis of lepidic lesions is critical for appropriate prognostication and management as five-year survival in patients with iLPA is lower than in those with AIS and MIA. We aimed to evaluate the accuracy of CT-guided core needle lung biopsy classifying LPA lesions and identify clinical and radiologic predictors of invasive disease in biopsied lesions. Thirty-four cases of adenocarcinoma with non-invasive lepidic growth pattern on core biopsy pathology that subsequently were resected between 2011 and 2018 were identified. Invasive LPA vs. non-invasive LPA (AIS or MIA) was defined based on explant pathology. Histopathology of core biopsy and resected tumor specimens was compared for concordance, and clinical, radiologic and pathologic variables were analyzed to assess for correlation with invasive disease. The majority of explanted tumors (70.6%) revealed invasive disease. Asian race (p = 0.03), history of extrathoracic malignancy (p = 0.02) and absence of smoking history (p = 0.03) were associated with invasive disease. CT-measured tumor size was not associated with invasiveness (p = 0.15). CT appearance of density (p = 0.61), shape (p = 0.78), and margin (p = 0.24) did not demonstrate a significant difference between the two subgroups. Invasiveness of tumors with lepidic growth patterns can be underestimated on transthoracic core needle biopsies. Asian race, absence of smoking, and history of extrathoracic malignancy were associated with invasive disease.

CT-Guided Percutaneous Core Needle Biopsy in Typing and Subtyping Lung Cancer: A Comparison to Surgery

Background: Lung cancer histologic types and subtypes are closely associated with treatment selection and prognosis prediction. In this study, we aim to evaluate the suitability of computed tomography-guided percutaneous core needle biopsy (CT-guided PCNB) in typing and subtyping lung cancer. Methods: From August 2007 to December 2015, the patients who underwent CT-guided PCNB and lung lesion resection were retrospectively collected and analyzed. All pathological sections were reassessed in consensus by 2 junior pathologists (group A) and 2 senior pathologists (group B), respectively. All cases were diagnosed on 3 levels: first, malignant and benign diagnosis; second, histologic types diagnosis; and third, histologic subtypes diagnosis and compared with surgery results. Pearson chi-square test was used to compare the differences of diagnostic accuracy between pathologists in group A and group B. Results: A cohort of 160 patients was included in this study. On the first level, the diagnostic accuracy was 90.63% (group A) and 94.38% (group B), (P = .20). On the second level, the diagnostic accuracy for malignant lesions, adenocarcinoma (ADC), and squamous cell carcinoma (SQC) were, respectively, 72.66%, 84.72%, and 69.05% (group A) and 76.98%, 90.28%, and 71.43% (group B) (P > .05). On the third level, the diagnostic accuracy for ADC subtypes were 26.39% (group A) and 55.56% (group B) (P < 0.01); for SQC subtypes were 28.57% (group A) and 38.10% (group B) (P = 0.36). Conclusion: Small specimens obtained by CT-guided PCNB were suitable for the diagnosis of lung cancer histologic types, which may contribute to the selection of a suitable treatment strategy for the unresectable lung cancers. While for the diagnosis of subtypes, discussion with experienced pathologists was recommended.

Cryobiopsy as a reliable technique for the preoperative identification of micropapillary/solid components in early-stage lung adenocarcinoma

OBJECTIVES

Micropapillary (MIP) and solid (SOL) subtypes of early-stage lung adenocarcinomas are associated with lymph node metastasis and local recurrence after limited resection. Preoperative identification of these components may influence the decisions of treatment strategy, additional lymph node evaluation, indication for limited resection, and extent of lymph node dissection. However, conventional biopsy specimens are insufficient for identifying these subtypes, especially MIP components. Cryobiopsy can collect larger tissue samples with fewer crush artifacts than conventional forceps biopsy, which would be helpful for detecting MIP/SOL components. Thus, this study aimed to analyze the feasibility of using cryobiopsy for MIP/SOL subtype detection.

MATERIAL AND METHODS

Consecutive patients who underwent surgery for clinical IA lung cancer following a preoperative diagnosis of adenocarcinoma by cryobiopsy at our institution between October 2017 and July 2019 were retrospectively examined. The concordance rate of MIP/SOL subtypes between the specimens obtained by cryobiopsy and surgery was investigated.

RESULTS

In total, 115 patients were evaluated. There were 26 (22.6%) and 14 (12.2%) patients with MIP and SOL subtypes, respectively. For concordance of MIP/SOL subtypes, the sensitivity was 65.7% (95% confidence interval [CI]: 57.7-65.7%). For the primary or secondary predominant patterns, a more satisfactory concordance rate of 72.2% (95% CI: 52.6-86.2%) was obtained. On assessing each subtype, high sensitivity was noted in SOL-predominant patterns (85.7%, 95% CI: 56.5%-96.0%) and MIP-secondary predominant patterns (83.3%, 95% CI: 45.8-97.0%). However, SOL-secondary predominant patterns revealed low sensitivity (0%, 95% CI, 0-38.2%). Overall, the MIP subtypes had higher sensitivity than the SOL subtypes (65.4% vs. 50.0%).

CONCLUSION

Cryobiopsy could be reliable for identifying MIP/SOL components, especially the MIP component, in clinical stage IA adenocarcinomas.

Solid histological component of adenocarcinoma might play an important role in PD-L1 expression of lung adenocarcinoma

BACKGROUND

In this study we aimed to clarify the PD-L1 positive expression in lung adenocarcinoma, including various adenocarcinoma subtypes paying particular attention to its component.

METHODS

A total of 307 lung adenocarcinoma patients who underwent lobectomy or segmentectomy, as well as systematic lymph node dissection (ND2a), from February 2008 to March 2020 at our hospital, were enrolled into the study. A final diagnosis of adenocarcinoma was obtained from the resected lung specimens of all 307 patients to determine the histological type, adenocarcinoma subtype, and component of adenocarcinoma by ethics of 5%. PD-L1 was immunohistochemically stained using the murine monoclonal antibody clone 22C3.

RESULTS

When PD-L1 expression-positive was defined by tumor proportion score (TPS) ≥1%, the positive cases were 6/33 in adenocarcinoma (Ad) in situ (AIS), 2/26 in minimally invasive Ad (MIA), 12/60 in lepidic predominant Ad (LPA), 44/91 in papillary predominant Ad (PPA), 24/49 in acinar predominant Ad (APA), 23/28 in solid predominant Ad (SPA), 4/7 in micropapillary predominant Ad (MPA), and 0/13 in invasive mucinous Ad (IMA). In the high proportion group (APA, PPA, SPA, and MPA) of PD-L1 expression, SPA was the only subtype which was statistically significant when both PD-L1 expression-positive was defined by TPS ≥ 1% (p < 0.0001) and TPS ≧ 50% (p < 0.0001). We then considered the solid component. We investigated 279 cases of the other subtype group excluding SPA. The group containing a solid component (≥5%) tended to be PD-L1 expression-positive both when defined by TPS ≥1% (p < 0.0001) and TPS ≧50% (p = 0.0049).

CONCLUSIONS

The PD-L1 expression tended to be positive when a solid component was confirmed (≥5%) in specimens of lung adenocarcinoma patients.

Rates of invasive disease and outcomes in NSCLC patients with biopsy suggestive of carcinoma in situ

INTRODUCTION

Carcinoma in situ is a rare non-invasive histology of non-small cell lung cancer (NSCLC) with excellent survival outcomes with resection. However, management of lung biopsy suggestive of in situ disease remains unclear. To inform decision-making in this scenario, we determined the rate of invasive disease presence upon resection of lesions with an initial biopsy suggestive of purely in situ disease.

METHODS

The study included 960 patients diagnosed with NSCLC from 2003 to 2017 in the National Cancer Database whose workup included a lung biopsy suggestive of in situ disease. Among the cohort who proceeded to resection, we identified the rate of invasive disease discovered on surgical pathology along with significant demographic and clinical contributors to invasion risk. Survival outcomes were measured for the observed cohort that did not receive local therapy after biopsy.

RESULTS

Invasive disease was identified at resection in 49.3 % of patients. Lesion size was associated with risk of invasive disease: 35.7 % for ≤1 cm, 45.2 % for 1-2 cm, 55.7 % for 2-3 cm, and 87.5 % for 3-5 cm (p < 0.001). Of patients with squamous histology, 61.5 % had invasive disease versus 46.5 % with adenocarcinoma histology (p = 0.026). On multivariable logistic regression, invasive disease remained associated with tumor size (OR 1.9 per cm, 95 % CI 1.5-2.4, p < 0.001), and squamous histology (OR 1.8, 95 % CI 1.1-3.2, p = 0.028). Overall survival at 3 years was 51.5 % in the observed cohort.

CONCLUSION

Nearly half of patients with biopsy suggestive of in situ disease had invasive disease at resection. Tumor size and histology are strong predictors of invasive disease and may be used for risk stratification. However, the findings support the practice of definitive therapy whenever feasible.

New International Association for the Study of Lung Cancer (IASLC) Pathology Committee Grading System for the Prognostic Outcome of Advanced Lung Adenocarcinoma

Simple Summary

This study investigated the association between survival outcome and the new grading system among advanced stage lung adenocarcinoma (LADC) (stages IIIA, IIIB and IV) patients who were diagnosed as LADC with a pathologic report according to a new grading system by the International Association for the Study of Lung Cancer (IASLC) pathology committee. The results indicate that the poorly differentiated group had a poorer prognosis in PFS, as did patients with wild-type EGFR who were treated with chemotherapy. No survival difference could be found among EGFR mutation patients. Older age and a lower body mass index also led to worse survival. Patients with poorly differentiated adenocarcinoma likewise had worse survival, especially compared to those with moderately differentiated adenocarcinoma. Our findings highlight that the therapeutic regimen should be adjusted for wild-type EGFR patients with poorly differentiated adenocarcinoma treated with chemotherapy to provide better outcomes. No survival difference could be seen among EGFR mutation patients.

Abstract

The impact of the new International Association for the Study of Lung Cancer pathology committee grading system for advanced lung adenocarcinoma (LADC) on survival is unclear, especially in Asian populations. In this study, we reviewed the prognostic outcomes of patients with late-stage disease according to the new grading system. We reviewed 136 LADC cases who underwent a small biopsy from 2007 to 2018. Tumors were classified according to the new grading system for LADC. Baseline characteristics (age, sex, smoking status, body mass index, and driver gene mutations) were analyzed. Kaplan–Meier and Cox regression analyses were used to determine correlations with the new grading system and prognosis. Patients with poorly differentiated adenocarcinoma were significantly correlated with a poor progression-free survival (PFS) (p = 0.013) but not overall survival (OS) (p = 0.154). Subgroup analysis showed that wild-type EGFR patients with poorly differentiated adenocarcinoma treated with chemotherapy had significantly worse PFS (p = 0.011). There was no significant difference in survival among the patients with epidermal growth factor receptor mutations who were treated with tyrosine kinase inhibitors. Patients aged >70 years and those with a BMI ≤ 25 kg/m² and wild-type patients had significantly worse OS in both univariate (HR = 1.822, p = 0.006; HR = 2.250, p = 0.004; HR = 1.537, p = 0.046, respectively) and multivariate analyses (HR = 1.984, p = 0.002; HR = 2.383, p = 0.002; HR = 1.632, p = 0.028, respectively). Despite therapy, patients with poorly differentiated tumors still fared worse than those with better differentiated tumors. No differences were found among the EGFR mutations treated with TKI. Our findings highlight that the therapeutic regimen should be adjusted for EGFR Wild-type patients with poorly differentiated adenocarcinoma treated with chemotherapy to provide better outcomes.

Histological subtypes of solid-dominant invasive lung adenocarcinoma: differentiation using dual-energy spectral CT

AIM

To investigate the value of dual-energy spectral computed tomography (DESCT) for evaluating the histological subtypes of solid-dominant invasive lung adenocarcinoma (SILADC).

MATERIALS AND METHODS

Sixty-seven patients with SILADC were enrolled. All patients underwent DESCT and were divided into Group I (those with a lepidic/acinar/papillary predominant pattern) and Group II (those with a solid/micropapillary predominant pattern) based on their correlation with prognosis. Patient clinicopathological characteristics, DESCT morphological features, and quantitative parameters of the tumours were compared between both groups. Multiparametric analysis was performed using binary logistic regression with DESCT findings. Receiver operating characteristic (ROC) curves were used to assess the diagnostic performance of single-parameter and multiparametric analysis.

RESULTS

Patient gender, lymph nodes status, pathological TNM stage, and histological differentiation significantly differed between the two groups (all p<0.05). Moreover, significant differences were observed between both groups in DESCT morphological features including tumour size, necrosis, calcification, air bronchogram, and vascular convergence sign, and quantitative parameters including K_{40-65 keV}, effective atomic number, and water concentration on unenhanced CT and iodine concentration in the arterial and venous phases (all p<0.05). Multiparametric analysis showed that tumour size, air bronchogram, K_{40-65 keV} and effective atomic number on unenhanced CT were the most effective variations for predicting the histological subtypes of SILADC and obtained an area under the ROC curve (AUC) of 0.906.

CONCLUSIONS

DESCT was useful for differentiating histological subtypes with different prognosis of SILADC.

Morphological, immune and genetic features in biopsy sample associated with the efficacy of pembrolizumab in patients with non-squamous non-small cell lung cancer

INTRODUCTION

The usefulness of the histopathology of biopsy samples for predicting the efficacy of immunotherapy in non-squamous, non-small cell lung cancer (NSq NSCLC) patients remains unclear.

METHODS

We retrospectively investigated the associations between the histopathological features in biopsy samples and survival outcomes in advanced NSq NSCLC patients receiving pembrolizumab. NSq NSCLC was classified histopathologically as morphological adenocarcinoma or non-small cell carcinoma (NSCC: absence of definitive features of either adenocarcinoma or a squamous morphology). We investigated the association between the tumor morphological features and immune/genetic features by examining the tumor PD-L1 expression and tumor mutation burden (TMB).

RESULTS

Among 33 advanced NSq NSCLC patients with tumor PD-L1 scores ≥ 50% receiving pembrolizumab as first-line therapy, a biopsy diagnosis of NSCC was associated with a significantly longer progression-free survival [median 16.8 vs. 2.3 months; hazard ratio (HR) 0.26; 95% CI 0.10-0.62, P = 0.01] and overall survival (median NR vs. 10.1 months; HR 0.35; 0.12-0.97, P = 0.04) as compared to that of morphological adenocarcinoma. In an analysis of 367 biopsy samples, the NSCC group showed a higher percentage of samples with PD-L1 scores ≥ 50% than the morphological adenocarcinoma group (35% vs. 10%). The NSCC group (n = 8) also showed a significantly higher TMB than the morphological adenocarcinoma group (n = 7) (median 236 vs. 25 mutations/whole exome, P = 0.01).

CONCLUSION

Absence of definitive morphological features in a biopsy sample could be a useful predictor of the efficacy of pembrolizumab in NSq NSCLC patients with tumor PD-L1 scores ≥ 50%, as these tumors are likely to show high tumor PD-L1 expression and high TMB.

High expression of CXCL14 is a biomarker of lung adenocarcinoma with micropapillary pattern

Lung adenocarcinoma with micropapillary pattern (MPP) has an aggressive malignant behavior. Limited resection should be avoided because of its high recurrence rate. If adenocarcinoma with MPP is diagnosed preoperatively, the selection of proper treatment is possible. To explore a preoperative biomarker for diagnosing MPP, we undertook RNA sequencing analysis of 25 clinical samples as the training set, including 6 MPP, 16 other adenocarcinoma subtypes, and 3 normal lung tissues. Unsupervised hierarchical clustering analysis suggested a presence of subgroup with MPP showing different gene expression phenotype. We extracted differentially expressed genes with high expression levels in MPP samples, and chose VSIG1, CXCL14, and BAMBI as candidate biomarkers for MPP. Reverse transcription-quantitative PCR analysis confirmed a significantly higher expression of VSIG1 (P = .03) and CXCL14 (P = .02) in MPP than others. In a validation set of 4 MPP and 4 non-MPP samples, CXCL14 expression was validated to be significantly higher in MPP than in non-MPP (P = .04). Comparing a total of 10 MPP and 20 non-MPP samples, the area under the curve of CXCL14 to distinguish MPP from others was 0.89. The threshold value was 0.0116, corresponding to sensitivity 80% and specificity 90%. In immunostaining of CXCL14, the staining score was significantly higher in MPP cases than others, where not only the MPP component but also other components showed heterogeneous staining in adenocarcinoma tissues with MPP. Moreover, a higher staining score of CXCL14 was significantly associated with poorer prognosis in all patients (P = .01) or within cases in stage I-III (P = .01). In summary, we identified CXCL14 as a possible diagnostic biomarker of MPP.

CT-Guided Core Biopsy for Peripheral Sub-solid Pulmonary Nodules to Predict Predominant Histological and Aggressive Subtypes of Lung Adenocarcinoma

BACKGROUND

Adenocarcinoma is the most common type of lung cancer, and pre-operative biopsy plays an important role to determine its major subtypes. As proposed by the International Association for the Study of Lung Cancer (IASLC), American Thoracic Society (ATS), and European Respiratory Society (ERS) in 2011, the predominant histological subtype of adenocarcinoma is an indicator of outcomes and recurrence rate. However, the value of CT-guided core biopsy in predicting the predominant subtype and detecting the presence of an aggressive subtype of adenocarcinoma, peripheral sub-solid nodule, has less been discussed.

METHODS

We retrospectively reviewed 318 consecutive peripheral sub-solid nodules that underwent percutaneous CT-guided lung biopsy and surgical resection, between October 2015 and December 2018 and were diagnosed as adenocarcinoma with histological subtype. The subtyping results from biopsy and surgical pathology were compared to evaluate the concordance rate.

RESULTS

The overall concordance rate between biopsy and surgical pathology in determining the predominant histological subtype was 64%. Better concordance was found in small tumors (≤ 2 cm), in predicting either predominant histology (χ² = 7.091, P = 0.008) or high grade adenocarcinoma, micropapillary and/or solid subtype, MIP-SOL (χ² = 22.301, P < 0.001). The analysis of ground glass opacity (GGO) component (C/T ratio) obtained significantly higher accuracy in the pure GGO group than in the other two groups in predicting predominant histology or high grade adenocarcinoma (χ² = 17.560, P < 0.001 and χ² = 61.938, P < 0.001, respectively).

CONCLUSIONS

CT-guided core biopsies provide additional value in predicting the histological subtype of lung adenocarcinoma after surgical resection, especially in small tumors (≤ 2 cm) or an initially pure GGO group.

Multivariate Analysis Of The Diagnostic Yield Of Conventional Bronchoscopy In Peripheral Lung Adenocarcinoma

Background

The new subtypes of lung adenocarcinoma reflect local invasive growth, pulmonary alveoli, and intraluminal spreading, while the effective improvement of the diagnostic yield of bronchoscopy still remains unclear. This study aims to explore whether the subtypes of lung adenocarcinoma and other factors affect the diagnostic yield of bronchoscopy.

Methods

All patients were performed 64-row CT examination and bronchoscopy.

Results

The bronchus cutoff sign in 48 cases and the endoscopic diagnostic yield was 60.4%. The lumen of the lobes and segments was invaded in 59 cases, and the endoscopic diagnostic yield was 54.2%.The lymph node metastasis was detected in 46 cases, and the endoscopic diagnostic yield was 60.9%. In addition, 42 cases showed acinar type-predominant, and the endoscopic diagnostic yield was 28.6%. Eighteen cases showed solid type-predominant, and the endoscopic diagnostic yield was 33.3%. The micropapillary type-predominant was noted in 17 cases, with the endoscopic diagnostic yield as 94.1%. The papillary type-predominant was in 14 cases, and the endoscopic diagnostic yield was 42.9%. The lepidic type-predominant was seen in 13 cases, and the endoscopic diagnostic yield was 7.7%. The mean diameter of tumors with a positive endoscopic diagnostic yield was 4.34±2.65cm, and the mean diameter of tumors with a negative diagnostic yield was 2.83±1.47cm. Multivariate analysis showed that micropapillary lung adenocarcinoma affected the endoscopic diagnostic yield (OR=37.594, 95% CI: 4.074-346.94) .Tumor diameter affects endoscopic diagnostic yield (OR=1.39, 95% CI: 1.073-1.802), bronchus cutoff sign is easy to obtain endoscopic diagnostic yield (OR=4.86, 95% CI: 1.606-14.704), and lymph node metastasis affects the endoscopic diagnostic yield (OR=3.696, 95% CI: 1.255-10.883).

Conclusion

The micropapillary subtype lung adenocarcinoma has a certain influence on the diagnostic yield of bronchoscopy. When the lung adenocarcinoma has a large tumor diameter, bronchus cutoff sign and lymph node metastasis, it is easy to obtain a diagnostic yield of bronchoscopy.

Interdisciplinary multimodality management of stage III nonsmall cell lung cancer

Stage III nonsmall cell lung cancer (NSCLC) comprises about one-third of NSCLC patients and is very heterogeneous with varying and mostly poor prognosis. It is also called "locoregionally or locally advanced disease". Due to its heterogeneity a general schematic management approach is not appropriate. Usually a combination of local therapy (surgery or radiotherapy, depending on functional, technical and oncological operability) with systemic platinum-based doublet chemotherapy and, recently, followed by immune therapy is used. A more aggressive approach of triple agent chemotherapy or two local therapies (surgery and radiotherapy, except for specific indications) has no benefit for overall survival. Until now tumour stage and the general condition of the patient are the most relevant prognostic factors. Characterising the tumour molecularly and immunologically may lead to a more personalised and effective approach. At the moment, after an exact staging and functional evaluation, an interdisciplinary discussion amongst the tumour board is warranted and offers the best management strategy.

Utility of Core Biopsy Specimen to Identify Histologic Subtype and Predict Outcome for Lung Adenocarcinoma

BACKGROUND

Lung adenocarcinoma histologic subtype is an important indicator of patient outcomes, so preoperative knowledge of subtype may be helpful to guide surgical planning. We evaluated the sensitivity and prognostic efficacy of specimens from computed tomography-guided core needle biopsies to predict histologic subtype and patient outcome after surgery.

METHODS

We retrospectively identified 221 patients with lung adenocarcinoma who underwent computed tomography-guided lung biopsy and subsequent surgical resection. Concordance, accuracy, specificity, and sensitivity of histologic subtypes from core biopsy specimens were compared with surgically resected specimens. Tumor characteristics and biopsy procedural factors were analyzed to determine impact on diagnostic sensitivity. Histologic subtype based on biopsy specimen, clinical, tumor, and treatment variables were also examined in relation to time to progression.

RESULTS

Overall concordance of biopsy samples with the predominant subtype from surgical specimens was 77%. Specificity (sensitivity) of detecting a nonaggressive and aggressive subtype were 86% (93%) and 95% (48%), respectively. Length of core specimen and percentage subtype composition in the surgically resected specimen were correlated with improved sensitivity but to a lesser extent with aggressive subtypes. Presence of an aggressive subtype in biopsy specimens was an independent predictor of progression after surgery (subdistribution hazard ratio, 2.51; 95% confidence interval, 1.28-4.94; p = 0.0075).

CONCLUSIONS

Specimens from computed tomography-guided core biopsies can predict lung adenocarcinoma progression after surgical resection. Future prospective studies should address the role of core biopsy in preoperative planning.

Thick-wall cavity predicts worse progression-free survival in lung adenocarcinoma treated with first-line EGFR-TKIs

BACKGROUND

Cavity occurs in 5.7 to 14.9% of patients with lung adenocarcinoma (ADC). However, the impact of cavity on the therapeutic response to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) in ADC patients with EGFR mutations remains unclear. The aim of the present retrospective study was to elucidate the incidence and detailed characteristics of EGFR-mutant cavitary ADC and investigate the efficacy of EGFR-TKI treatment in this subgroup.

METHODS

Two hundred seventy-six consecutive patients with advanced EGFR-mutant lung ADC treated with first-line EGFR-TKIs were enrolled. Cavitation and the thickness of cavity wall were assessed based on high-resolution computed tomography scans. Progression-free survival (PFS) was analyzed by the Kaplan-Meier plots and the log-rank test was used to calculate the significance between groups.

RESULTS

Cavity occurred in 5.4% (15/276) of patients with EGFR-mutant lung ADC and was more prevalent among male patients (66.7% vs. 33.3%, P = 0.008). Of the 15 EGFR-mutant cavitary ADC, 9 patients had exon 19 deletion (19DEL) and 6 harbored L858R mutation, 9 patients had thick-wall cavity while 6 had thin-wall cavity. Cavity had an adverse impact on the PFS of EGFR-mutant ADC treated with first-line EGFR-TKIs (noncavity versus cavity, 11.0 versus 6.5 months, hazard ratio [HR]: 0.33, 95% confidence interval [CI], 0.15-0.73, P = 0.003). The impaired effect was only observed in patients with L858R mutation (11.0 vs. 4.2 months, HR: 0.05, 95%CI, 0.01-0.27, P = 0.0003) but not in those with 19DEL (10.4 versus 9.7 months, HR: 0.73, 95%CI, 0.30-1.75, P = 0.483). All six L858R-mutant cavitary ADC patients had thick-wall cavity while thick-wall cavity was only identified in one thirds (3/9) of patients with 19DEL. Further analyses showed that patients with thick-wall cavity had worse PFS (6.0 versus 11.0 months, P = 0.013). Multivariate analysis identified cavity as an independent predictive factor for PFS (HR: 0.49, 95% CI, 0.26-0.90, P = 0.022).

CONCLUSION

Cavitary ADC was associated with a worse PFS of first-line EGFR-TKI therapy, mainly in those with L858R mutation. Thick-wall cavity formation may be the main cause that contribute to the worse PFS.

Micropapillary and/or Solid Histologic Subtype Based on Pre-Treatment Biopsy Predicts Local Recurrence After Thermal Ablation of Lung Adenocarcinoma

BACKGROUND

To investigate whether histologic subtyping from biopsies can predict local recurrence after thermal ablation for lung adenocarcinoma.

METHODS

Patients treated with CT-guided thermal ablation for lung adenocarcinoma that had pre-ablation needle biopsy with analysis of histologic components were identified. Age, gender, smoking status, treatment indication (primary stage 1 tumor versus salvage), histologic subtype, ground-glass radiographic appearance, tumor size, ablation modality, and ablation margin were evaluated in relation to time to local recurrence (TTLR). Cumulative incidence of recurrence (CIR) was calculated using competing risks analysis and compared across groups using Fine and Grey method with clustering. Multivariate analysis was conducted with stepwise regression.

RESULTS

There were 53 patients with 57 tumors diagnosed as adenocarcinoma on pre-ablation biopsy and with histologic subtype analysis. Of these, 19% (11) had micropapillary components, 14% (8) had solid components, and 26% (15) had micropapillary and/or solid components. In the univariate analysis, solid (subdistribution hazard ratio [SHR] = 4.04, p = 0.0051, 95% confidence interval [CI] = 1.52-10.7), micropapillary (SHR = 3.36, p = 0.01, CI = 1.33-8.47), and micropapillary and/or solid components (SHR = 5.85, p = 0.00038, CI = 2.21-15.5) were significantly correlated with shorter TTLR. On multivariate analysis, the presence of micropapillary and/or solid component (SHR = 11.4, p = 0.00021, CI: 3.14-41.3) was the only independent predictor of TTLR. The 1-, 2-, and 3-year CIR in patients with micropapillary and/or solid components was 33, 49, and 66% compared to 5, 14, and 18% in patients with no micropapillary or solid components on biopsy specimens.

CONCLUSION

Micropapillary and/or solid histologic components identified in pre-ablation biopsy are associated with shorter TTLR after thermal ablation of lung adenocarcinoma.

Inaccuracy of lung adenocarcinoma subtyping using preoperative biopsy specimens

BACKGROUND

The prognostic significance of the new classification of lung adenocarcinoma proposed in the 2015 World Health Organization guideline has been validated. This study aimed to compare the preoperative classification of the adenocarcinoma subtype based on computed tomography-guided 18-gauge core needle biopsy (CTNB) or radial probe endobronchial ultrasound (R-EBUS) specimens, with the postoperative classification based on the resected specimens.

METHODS

We retrospectively analyzed a consecutive series of 128 patients (60 CTNB and 68 R-EBUS) who underwent surgery for preoperatively confirmed lung adenocarcinoma between 2010 and 2014. Comprehensive histological subtyping was performed according to the 2015 World Health Organization classification system. Diagnostic concordance of subtypes between small biopsy and resection specimens was assessed.

RESULTS

Concordant subtyping of adenocarcinomas between the predominant pattern on resections and biopsy sections was observed in 58.6% of cases (75 of 128; 95% confidence interval [CI], 49.9%-66.8%). Preoperative subtyping was accurate in only 30% of samples (3 of 10) with a predominance of solid patterns. None of the 5 micropapillary predominant cases was detected by CTNB or R-EBUS. For the concordance of the presence or absence of micropapillary/solid component, the sensitivity was as low as 16.5% (95% CI, 9.1%-26.5%). The detection rate by CTNB/R-EBUS increased with the increase in the percentage of micropapillary/solid component; however, even in the ≥40% micropapillary/solid group, only 24% of cases were detected by CTNB/R-EBUS.

CONCLUSIONS

The accuracy of the estimation of adenocarcinoma histological subtype based on preoperative biopsy sections was unsatisfactory.

Tumor B7-H3 (CD276) expression and smoking history in relation to lung adenocarcinoma prognosis

OBJECTIVES

Compared with non-smoking counterparts, smoking-associated lung cancers have a higher mutational load, resulting in the creation of more tumor neoantigens and increased immunogenicity. B7-H3 (also known as CD276) belongs to a family of immune modulators that includes PD-1 and PD-L1 (also known as B7-H1 or CD274). Considering the evidence that PD-L1 inhibitors have been shown to be more effective against lung cancer in smokers, we herein examined the prognostic interaction of tumor B7-H3 expression level with smoking history in lung adenocarcinoma patients.

MATERIALS AND METHODS

Using tissue microarrays comprising 270 consecutive cases of lung adenocarcinoma, we evaluated tumor B7-H3 expression by immunohistochemistry. We examined the prognostic association between B7-H3 expression levels and smoking history, using Cox proportional hazards regression analysis and the log-rank test. Additionally, we used logistic regression analysis to examine the correlations between B7-H3 expression levels and clinicopathological/molecular features of lung adenocarcinoma.

RESULTS

The association of B7-H3 expression with survival differed by smoking history (P_interaction=0.014); high B7-H3 expression was associated with decreased lung cancer-specific survival in moderate/heavy-smoking patients (smoking index [SI]≥400) (hazard ratio [HR]=3.07, 95% confidence interval [CI]=1.74-5.49, P=0.0001; log-rank: P<0.0001), but not in non/light-smoking patients (SI<400) (HR=1.14, 95% CI=0.63-1.96, P=0.64; log-rank: P=0.64). Interestingly, in moderate/heavy-smoking patients, high B7-H3 expression was associated with decreased survival in stage I cancer (log-rank; P=0.0005), whereas it showed no significant difference of survival in stage II-IV cancer (P=0.37). High B7-H3 expression was associated with smokers (univariable odds ratio [OR]=2.63, 95% CI=1.51-4.65; P=0.0005) and independently associated with EGFR wild-type status (multivariable OR=2.80, 95% CI=1.38-5.84; P=0.0042).

CONCLUSIONS

We demonstrated that the prognostic association of B7-H3 expression indeed differed according to smoking history. Our study also showed the significant association of high B7-H3 expression with EGFR wild-type and smoking patients, indicating the potential effectiveness of anti-B7-H3 therapy for EGFR wild-type or smokers' lung adenocarcinoma.

WITHDRAWN: Tumor B7-H3 (CD276) expression and smoking history in relation to lung adenocarcinoma prognosis

The Publisher regrets that this article is an accidental duplication of an article that has already been published in The Journal of Lung Cancer - http://dx.doi.org/10.1016/j.lungcan.2016.11.013. Please see online announcement for additional details. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Histologic Subtype in Core Lung Biopsies of Early-Stage Lung Adenocarcinoma is a Prognostic Factor for Treatment Response and Failure Patterns After Stereotactic Body Radiation Therapy

PURPOSE

Stereotactic body radiation therapy (SBRT) has emerged as an effective treatment for early-stage lung cancer. The histologic subtype of surgically resected lung adenocarcinoma is recognized as a prognostic factor, with the presence of solid or micropapillary patterns predicting poor outcomes. We describe the outcomes after SBRT for early-stage lung adenocarcinoma stratified by histologic subtype.

METHODS AND MATERIALS

We identified 119 consecutive patients (124 lesions) with stage I to IIA lung adenocarcinoma who had undergone definitive SBRT at our institution from August 2008 to August 2015 and had undergone core biopsy. Histologic subtyping was performed according to the 2015 World Health Organization classification. Of the 124 tumors, 37 (30%) were a high-risk subtype, defined as containing a component of solid and/or micropapillary pattern. The cumulative incidences of local, nodal, regional, and distant failure were compared between the high-risk and non-high-risk adenocarcinoma subtypes using Gray's test, and multivariable-adjusted hazard ratios (HRs) were estimated from propensity score-weighted Cox regression models.

RESULTS

The median follow-up for the entire cohort was 17 months and for surviving patients was 21 months. The 1-year cumulative incidence of and adjusted HR for local, nodal, regional, and distant failure in high-risk versus non-high-risk lesions was 7.3% versus 2.7% (HR 16.8; 95% confidence interval [CI] 3.5-81.4), 14.8% versus 2.6% (HR 3.8; 95% CI 0.95-15.0), 4.0% versus 1.2% (HR 20.9; 95% CI 2.3-192.3), and 22.7% versus 3.6% (HR 6.9; 95% CI 2.2-21.1), respectively. No significant difference was seen with regard to overall survival.

CONCLUSIONS

The outcomes after SBRT for early-stage adenocarcinoma of the lung correlate highly with histologic subtype, with micropapillary and solid tumors portending significantly higher rates of locoregional and metastatic progression. In this context, the histologic subtype determined from core biopsies is a prognostic factor and could have important implications for patient selection, adjuvant treatment, biopsy methods, and clinical trial design.