Does lung adenocarcinoma subtype predict patient survival?: A clinicopathologic study based on the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society international multidisciplinary lung adenocarcinoma classification. J Thorac Oncol. 2011;6:1496-1504. [PMID: 21642859 DOI: 10.1097/jto.0b013e318221f701]

Stereotactic ablative radiotherapy (SABR) in early stage non-small cell lung cancer: Comparing survival outcomes in adenocarcinoma and squamous cell carcinoma

PURPOSE

Recent retrospective studies have demonstrated mixed results regarding the histologic association of squamous cell carcinoma (SCC) with reduced overall survival in patients with early-stage non-small cell lung cancer (ES-NSCLC) treated with stereotactic ablative radiotherapy (SABR).

METHODS

We queried the National Cancer Database (NCDB) for ES-NSCLC (T1-2N0, Stage I-IIA) patients with SCC or adenocarcinoma (ADC) treated with SABR. Univariable and multivariable analyses identified characteristics predictive of overall survival. Cox proportional hazard ratios with propensity adjustment were used to mitigate indication bias between the two histologic arms.

RESULTS

Ultimately 15,110 ES-NSCLC patients with either ADC (n = 8,924) or SCC (n = 6,186) were eligible for analysis. Univariable analysis demonstrated a median overall survival of 44 months and 33 months (p < 0.0001) and 5-year overall survival of 36% and 24% (p < 0.0001) in patients diagnosed with ADC and SCC, respectively. SCC histology, remained an independent predictor of worse survival on propensity score matched multivariable comparison (p < 0.0001). Patients with SCC were more likely to have T2 lesions and poorly differentiated grade. Females, African American race, T1 lesions, and age <75 years were also associated with improved survival. Conclusion SCC histology was an independent prognosticator of worse survival in patients with ES-NSCLC treated with SABR, thus corroborating the results of previous studies. Randomized, prospective studies are needed to further validate these findings.

Primary Pulmonary Colloid Adenocarcinoma: How Can We Obtain a Precise Diagnosis?

A 76-year-old asymptomatic man was found to have a mass in the right lower lung field. Although the presence of a mucinous component in the majority of the tumor was shown by magnetic resonance imaging, the presence of cancer cells was suspected by contrast enhancement on computed tomography (CT) and based on the partial accumulation in the marginal regions of the tumor on fluorodeoxyglucose-positron emission tomography (FDG-PET). A transbronchial lung biopsy was non-diagnostic, but resection of the mass resulted in a diagnosis of colloid adenocarcinoma. The findings from combined contrast CT and FDG-PET may raise the suspicion of colloid adenocarcinoma and prompt the consideration of surgical resection.

A nomogram to predict prognosis in patients undergoing sublobar resection for stage IA non-small-cell lung cancer

Introduction

This study aimed to develop a practical nomogram to predict prognosis in patients who are undergoing sublobar resection for stage IA non-small-cell lung cancer (NSCLC). Data from Surveillance, Epidemiology, and End Results (SEER) databases were used to construct the nomogram.

Methods

Data from patients undergoing sublobar resection for stage IA NSCLC diagnosed between 2004 and 2014 were extracted from the SEER database. Factors that may predict the outcome were identified using the Kaplan–Meier method and the Cox proportional-hazards model. A nomogram was constructed to predict the 3- and 5-year overall survival (OS) and lung cancer-specific survival (LCSS) rates of these patients. The predictive accuracy of the nomogram was measured using the concordance index (C-index) and calibration curve.

Results

A total of 4,866 patients were selected for this study. Using univariate and multivariate analyses, eight independent prognostic factors associated with OS were identified, including sex (P<0.001), age (P<0.001), race (P=0.043), marital status (P=0.009), pathology (P=0.004), differentiation (P<0.001), tumor size (P<0.001), and surgery (P=0.001), and five independent prognostic factors associated with LCSS were also identified, including sex (P<0.001), age (P<0.001), differentiation (P<0.001), tumor size (P<0.001), and surgery (P=0.011). A nomogram was established based on these results and validated using the internal bootstrap resampling method. The C-index of the established nomogram for OS and LCSS was 0.649 (95% CI: 0.635–0.663) and 0.640 (95% CI: 0.622–0.658), respectively. The calibration curves for probability of 3-, and 5-year OS and LCSS rates demonstrated good agreement between the nomogram prediction and actual observation.

Conclusion

This innovative nomogram delivered a relatively accurate individual prognostic prediction for patients undergoing sublobar resection for stage IA NSCLC.

The Association Between Imaging Features of TSCT and the Expression of PD-L1 in Patients With Surgical Resection of Lung Adenocarcinoma

OBJECTIVES

Programmed death-ligand 1 (PD-L1) expression might serve as a predictive biomarker for immune checkpoint inhibitors in lung cancer. However, the relationship between PD-L1 expression and imaging features of lung cancer has not been fully understood.

PATIENTS AND METHODS

A total of 350 patients with pathologically confirmed adenocarcinoma who received surgical treatment and had preoperative thin section computed tomography (CT) examination were included. Quantitative CT features including the mean CT value and tumor mass were measured on multiplanar reconstructed images. PD-L1-positive tumor was defined as the tumor proportion score > 5%.

RESULTS

Seventy-four of 350 (21.1%) specimens were detected as PD-L1-positive tumors. PD-L1 expression was adversely associated with epidermal growth factor receptor mutation status (P < .001) and was significantly associated with invasive adenocarcinomas rather than preinvasive lesions and minimally invasive adenocarcinomas (P < .001). Multivariate analysis identified absence of surrounding ground glass opacity (P = .022), shape (P = .008), pleural indentation (P = .007), tumor mean CT value (P = .004), and the ratio of consolidation mass to tumor mass (P = .003) as being significantly associated with the expression of PD-L1. To improve the diagnostic accuracy, a joint model that combined 5 imaging traits was conducted. The area under the curve of the joint model was 0.783, with a sensitivity of 81.1% and specificity of 64.1%, respectively.

CONCLUSION

PD-L1 expression was associated with pathologic invasiveness of adenocarcinomas and CT features, which suggested the possibility of predicting PD-L1 expression status via imaging features.

Should minimally invasive lung adenocarcinoma be transferred from stage IA1 to stage 0 in future updates of the TNM staging system?

Background

The 8th International Association Study of Lung Cancer (IASLC) TNM classification staging project for lung cancer has classified patients with adenocarcinoma in situ (AIS) into stage 0, while patients with a minimally invasive adenocarcinoma (MIA) were classified into stage IA1. However, MIA patients, similar to AIS patients, have an approximately a 100% 5-year survival. This study aimed to investigate if MIA could be transferred from stage IA to stage 0 in the next TNM staging system.

Methods

We retrospectively reviewed 1,524 consecutive patients with a pathologically confirmed AIS, MIA and an invasive adenocarcinoma (IADC) in stage IA1. Disease-free survival (DFS) and overall survival (OS) were analyzed to evaluate survival difference between these three groups.

Results

There were 412 AIS, 675 MIA and 437 IADC patients in stage IA1. No statistically significant differences for DFS and OS (P=0.109) were seen between the AIS and MIA groups. Patients of the IADC group had significantly worse DFS (P=0.003) but the OS rate (P=0.941) was insignificant when compared with the MIA patients. Similar survival results were seen when comparisons were made between the IADC and AIS/MIA groups. The IADC group had a worse DFS (P=0.001) rate but no OS (P=0.380) difference with the AIS/MIA groups.

Conclusions

Patients with AIS and MIA had similar post-surgical survival rates. We propose that MIA may potentially be transferred from IA1 to stage 0 in the future.

Molecular signatures in IASLC/ATS/ERS classified growth patterns of lung adenocarcinoma

BACKGROUND

The current classification of human lung adenocarcinoma defines five different histological growth patterns within the group of conventional invasive adenocarcinomas. The five growth patterns are characterised by their typical architecture, but also by variable tumor biological behaviour.

AIMS

The aim of this study was to identify specific gene signatures of the five adenocarcinoma growth patterns defined by the joint IASLC/ATS/ERS working group.

METHODS

Total RNA from microdissected adenocarcinoma tissue samples of ten lepidic, ten acinar, ten solid, nine papillary, and nine micropapillary tumor portions was isolated and prepared for gene expression analysis. Differential expression of genes was determined using the R package "LIMMA". The overall significance of each signature was assessed via global test. Gene ontology statistics were analysed using GOstat. For immunohistochemical validation, tissue specimens from 20 tumors with solid and 20 tumors with lepidic growth pattern were used.

RESULTS

Microarray analyses between the growth patterns resulted in numerous differentially expressed genes between the solid architecture and other patterns. The comparison of transcriptomic activity in the solid and lepidic patterns revealed 705 up- and 110 downregulated non-redundant genes. The pattern-specific protein expression of Inositol-1,4,5-trisphosphate-kinase-A (ITPKA) and angiogenin by immunohistochemistry confirmed the RNA levels. The strongest differences in protein expression between the two patterns were shown for ITPKA (p = 0.02) and angiogenin (p = 0.113).

CONCLUSIONS

In this study growth pattern-specific gene signatures in pulmonary adenocarcinoma were identified and distinct transcriptomic differences between lung adenocarcinoma growth patterns were defined. The study provides valuable new information about pulmonary adenocarcinoma and allows a better assessment of the five adenocarcinoma subgroups.

Pulmonary mucinous adenocarcinomas: a clinicopathologic series with emphasis on the prognostic significance of spread through alveolar spaces, and presence of solid growth component

Background

Mucinous adenocarcinoma is often considered a relatively poor prognostic group among adenocarcinomas of the lung and has a high rate of pulmonary recurrence. Pathologic parameters predicting poor outcome have not been extensively studied, including the presence of spread through alveolar spaces (STAS).

Methods

We retrospectively studied time to lung recurrence and time to distant metastasis in 30 mucinous lung tumors, in relationship to histologic parameters, including spread through alveolar spaces, tumor size, invasive size, % invasive size, growth pattern (solid or cribriform, acinar, papillary, micropapillary, and lepidic), type of mucin-producing cell, and TTF-1 positivity.

Results

Median follow-up was 40 months. There were 7 patients (23%) with lung recurrence (mean 22 months) and 7 (23%) with distant metastases (mean 3.7 months). Columnar / goblet cell type was inversely correlated with TTF-1 expression (p = 0.01). The only pathologic parameters associated with outcome were STAS for lung recurrence (p = .005) and solid/cribriform growth (≥ 20% of tumor) for distant metastasis (p = 0.003).

Conclusions

Mucinous adenocarcinomas of the lung are similar to non-mucinous prognostically, in that STAS and solid growth are poor prognosticators, for local and distant recurrence, respectively. The growth patterns of mucinous adenocarcinomas should be reported similar to reporting of non-mucinous adenocarcinomas.

[Factors Influencing the Progression Trend of Early Lung Cancer and CT Findings]

背景与目的

不同类型的肺部结节具有不同的体积倍增时间（volume doubling time, VDT）。目前针对不同病理类型早期肺腺癌VDT的研究较少。本研究通过回顾性分析143例早期肺腺癌的影像资料，探讨早期肺腺癌的进展趋势及相关影响因素，为临床制订其随访策略提供参考。

方法

依据2015版世界卫生组织肺肿瘤分类标准和第8版肿瘤肿瘤-淋巴结-转移（tumor-node-metastasis, TNM）分期标准，对143例早期肺腺癌进行分类及分期。参考修正版Schwartz公式计算不同病理类型肺腺癌的VDT。

结果

143例早期肺腺癌中，有50例（34.97%）出现进展，多因素分析显示影响因素包括随访时间、结节大小、病理类型、结节类型和病理分期。附壁生长为主型肺腺癌（lepidic predominant adenocarcinoma, LPA）的VDT为（594±272）d，伴少量附壁生长成分浸润性腺癌的VDT为（520±285）d，完全浸润性腺癌的VDT为（371±183）d，3类进展性早期肺腺癌的VDT有统计学差异（P=0.044）。

结论

在早期肺腺癌中，约有35%的肿瘤处于进展阶段，是否含有附壁生长成分是影响肿瘤进展速度的重要因素。

Clinical Presentation and Treatment Options for Clear Cell Lung Cancer: University of Cincinnati A Case Series and Literature Review of Clear Cell Lung Cancer

Clear cell carcinomas are common finding in renal, ovarian and uterine carcinomas. However, clear cell lung cancer (CCLC), first described by Liebow and Castleman in 1963, is considered an extremely rare variant of lung tumors. The 2011 WHO classification of lung tumors considered CCLC as a rare cytologic feature of squamous cell or adenocarcinomas. It is no longer recognized as a formal subtype, albeit it can be referred to in the pathological diagnosis as “with clear cell features” even with marginal fractions of the tumor cells. Such recognition is needed since the variation in clinical features and outcome in this subset of patients. The disease has a clinically vague natural history, is characterized by slight female predominance and is often seen in the elderly. As frequently encountered with rare diseases, its clinical course and treatment options have many questions still yet to be answered. In this paper, we review both the natural history and treatment options mentioned in literature, in the light of our experience by reporting a case series of four patients diagnosed with CCLC and highlight their aspects.

Predictive accuracy of lepidic growth subtypes in early-stage adenocarcinoma of the lung by quantitative CT histogram and FDG-PET

OBJECTIVES

The aim of this study was to analyze the accuracy of computed tomography (CT) and F-18 fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) to distinguish lepidic growth adenocarcinoma (LGA), including adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), and lepidic-predominant adenocarcinoma, all of which have favorable survival outcomes, from the more aggressive and invasive non-LGA subtypes.

MATERIALS AND METHODS

We identified 225 patients with c-0/I adenocarcinoma of the lung who underwent PET/CT and 3DCT followed by complete resection. Maximum standardized uptake values (SUVmax) of FDG and several histogram parameters were analyzed. Histological grades were classified according to the predominant subtype (G1: lepidic; G3: micropapillary or solid; and G2: subtypes other than G1/G3).

RESULTS

The proportion of pathological invasive factors (lymphatic vessel involvement/blood vessel invasion/pleural invasion/lymph node metastasis) of patients with preinvasive adenocarcinoma, G1, G2, and G3 tumors were 0%, 3.6%, 48.0%, and 100%, respectively; p <  0.001). Multivariate analysis with CT-related parameters demonstrated that 75^th percentile CT attenuation value (75^th%, p <  0.001) and maximum CT attenuation value (maxCT, p =  0.009) were associated with incidence of non-LGA, whereas the value of SUVmax demonstrated a significant correlation (p <  0.001). When all patients were dichotomized according to ground-glass opacities (GGO)/solid-dominancy for CT maximum diameter, a significant correlation with non-LGA was shown in patients with solid-dominant tumor on SUVmax (p <  0.001) and with GGO-dominant tumor on 75^th% (p =  0.006) and maxCT (p =  0.007). The combination of one of the two significant histogram parameters and SUVmax revealed higher predictive performance for pathological high malignant features (positive pathological invasive factors, non-LGA, and the highly malignant subtype covering G2 with moderately or poorly-differentiated carcinoma and G3) than the individual use of either factor.

CONCLUSION

The 75^th%, maxCT, and SUVmax were highly useful in distinguishing LGA from non-LGA in c-0/I adenocarcinoma.

Micropapillary or solid pattern predicts recurrence free survival benefit from adjuvant chemotherapy in patients with stage IB lung adenocarcinoma

Background

Our study aimed to evaluate the prognostic significance and adjuvant chemotherapy (ACT) benefits of a micropapillary/solid (MS) pattern in patients with stage IB lung adenocarcinoma.

Methods

Patients with pathologically-confirmed stage IB adenocarcinoma who underwent surgical resection between January 2009 and December 2011 were included. The tumors were reclassified into three categories: MS patterns absent (MS-); non-predominant MS patterns (MS+); predominant MS (MS++). The correlations of prognosis and ACT with recurrence-free survival (RFS) were evaluated.

Results

Overall, 497 (MS-, n=269; MS+, n=177; MS++, n=51) patients were enrolled in the study. In univariate analysis, the MS+ [hazard ratio (HR), 1.437; 95% confidence interval (CI), 1.030-2.006; P=0.033] and MS++ (HR, 2.818; 95% CI, 1.792-4.432; P<0.001) groups had significantly poor prognosis compared with MS- group. Multivariate analysis revealed that age ≥65 (HR, 1.504; 95% CI, 1.077-2.099; P=0.017), serum level of carcinoembryonic antigen (CEA) ≥10 ng/mL (HR, 1.658; 95% CI, 1.048-2.623; P=0.031) and MS++ (HR, 2.529; 95% CI, 1.550-4.126; P<0.001) were significant prognostic factors. Furthermore, subgroup analysis showed that MS++ patients but not MS- and MS+ derived RFS (recurrence-free survival) benefit from ACT (HR, 0.357; 95% CI, 0.152-0.836; P=0.018).

Conclusions

MS pattern successfully differentiated the prognosis difference among stage IB lung adenocarcinomas and identified patients who benefitted from ACT.

Sex-Dependent Staging in Non-Small-Cell Lung Cancer; Analysis of the Effect of Sex Differences in the Eighth Edition of the Tumor, Node, Metastases Staging System

INTRODUCTION

Non-small-cell lung cancer (NSCLC) has disproportionately negative outcomes in men compared with women. The importance of the relationship between sex and tumor, node, metastases (TNM) staging system remains unknown. The objective of this study was to investigate the effect of sex on NSCLC survival for each stage in the eighth edition of the TNM staging system in NSCLC.

PATIENTS AND METHODS

Two cohorts treated surgically with curative intent between 2000 and 2010 were analyzed. The primary cohort was from Australia with a second population set from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate analyses of putative and validated prognostic factors were undertaken to investigate sex-dependent prognostication with detailed analyses of sex differences in each TNM stage. The primary outcome was disease-specific survival (DSS) at 5 years.

RESULTS

Inclusion criteria were met by 555 patients in the Australian cohort, 335 men (60.4%) and 220 (39.6%) women; and 47,706 patients from the SEER cohort, 24,671 men (51.7%) and 23,035 women (48.3%). Five-year DSS was significantly worse for men in multivariate analyses for the Australian (hazard ratio [HR], 1.44; 95% confidence interval [CI], 1.04-1.98; P = .026) and SEER (HR, 1.24; 95% CI, 1.20-1.28; P < .001) cohorts. Detailed analysis of TNM stage sex differences revealed a consistent pattern of men having worse survival than women across stages in both cohorts.

CONCLUSION

The poorer survival in men with NSCLC presents research and clinical communities with an important challenge. This study's findings suggest that for men and women diagnosed with NSCLC, and managed surgically, stage-specific outcomes should be quoted separately and consideration to a rapid prognostic score with sex combined with staging as a key element.

Novel method for rapid identification of micropapillary or solid components in early-stage lung adenocarcinoma

OBJECTIVE

Sublobar resection may be insufficient for early-stage lung adenocarcinoma with micropapillary or solid components because of the associated higher incidence of locoregional recurrence. This study sought to establish a novel method for rapidly identifying their presence to facilitate decision making for sublobar resection.

METHODS

Antibody arrays of adhesion and apoptosis molecules were applied for adenocarcinomas with or without micropapillary/solid components to identify differentially expressed proteins. A semi-dry dot-blot system that visualizes the presence of target proteins was used to determine the presence of micropapillary or solid components in a prospective cohort of patients with clinical stage I who underwent operation. Sensitivity and specificity were calculated by comparing semi-dry dot-blot results with pathologic examinations.

RESULTS

Insulin-like growth factor-binding protein 2 and P-cadherin were found more frequently in the micropapillary or solid positive group, and these were used as the target proteins in the semi-dry dot-blot system for detection of micropapillary or solid components. A total of 68 nodules with a mean size of 2.3 ± 0.7 cm, including 13 (19.1%) with a micropapillary and 20 (29.4%) with a solid pattern, were recruited. Micropapillary or solid (+) lesions were more likely to have lymph node upstaging, greater diameter, and higher maximum standardized uptake value. The specificity and sensitivity for detecting the minor presence of micropapillary or solid component using the semi-dry dot-blot method were 94.4% (95% confidence interval, 81.3-99.3) and 65.6% (95% confidence interval, 46.8-81.4), respectively. The average test duration was 26.9 ± 2.5 minutes.

CONCLUSIONS

Detecting insulin-like growth factor-binding protein 2 and P-cadherin via the semi-dry dot-blot method could identify micropapillary or solid components in early-stage lung adenocarcinoma in a short processing time.

High CCR4 expression in the tumor microenvironment is a poor prognostic indicator in lung adenocarcinoma

Background

Clinical trials of anti-CCR4 antibody for solid cancers with or without other immune-modulating agents including immune checkpoint blockade therapy are currently underway. However, little is known about the roles of CCR4⁺ lymphocytes and their prognostic impact in lung cancer. We hypothesized that high CCR4 expression in the tumor microenvironment would be associated with a poor prognosis and would act as a biomarker in lung adenocarcinoma.

Methods

First, the prognostic impact of CCR4 gene expression was explored using pooled data from public transcriptomic databases with online survival analysis software. Second, tissue microarrays (TMAs) were constructed from resected lung adenocarcinoma specimens from tumors up to 3 cm in size. The density of CCR4⁺ lymphocytes infiltrating the tumor was then assessed by immunohistochemistry and related to survival. Confounding factors were controlled for by multivariate analysis using the Cox proportional hazards model.

Results

Higher than median expression of the CCR4 gene was identified as an independent poor prognostic factor for overall survival (OS) by multivariate analysis of 720 lung adenocarcinoma patients in the public databases [HR =1.55 (95% CI: 1.03-2.35), P=0.037]. Consistent with this, high CCR4⁺ tumor-infiltrating lymphocyte (TIL) density was found to be an independent poor prognostic factor for both OS [HR =2.24 (1.01-5.34), P=0.049] and recurrence-free survival (RFS) [HR =2.20 (1.16-4.39), P=0.017] in the patients from whom TMA were obtained (n=180). Age, male gender, predominantly non-lepidic histological subtype, nodal involvement, and low CD8⁺ TIL density were also independent poor prognostic factors. However, FOXP3 gene expression and Foxp3⁺ lymphocyte infiltration did not possess any prognostic value in either study.

Conclusions

High CCR4 expression in the tumor microenvironment may be a poor prognostic factor in lung adenocarcinoma. Patients with high CCR4⁺ lymphocyte infiltration may have a poor prognosis and thus be suitable candidates for clinical trials of anti-CCR4 antibody treatment.

Cumulative smoking dose affects the clinical outcomes of EGFR-mutated lung adenocarcinoma patients treated with EGFR-TKIs: a retrospective study

Background

Although lung adenocarcinoma with activating epidermal growth factor receptor (EGFR) mutations is common in never smokers, one-third of the patients are ever-smokers. We aimed to investigate the effect of cumulative smoking dose(CSD) on clinical outcomes, including progression-free survival (PFS) and overall survival (OS), in patients with EGFR-mutated lung adenocarcinoma receiving EGFR-tyrosine kinase inhibitors (TKIs).

Methods

We retrospectively analyzed 142 patients with EGFR-mutation positive advanced or recurrent lung adenocarcinoma who were administered gefitinib, erlotinib, afatinib, and osimertinib. These patients were classified based on their CSD as never smokers, light smokers (≤10 pack-years [PYs]), moderate smokers (11–30 PYs), and heavy smokers (> 30 PYs). PFS and OS were analyzed according to smoking subgroups via Kaplan-Meier curves.

Results

Among the 142 patients, 91 (64.1%), 12 (8.5%), 22 (15.5%), and 17 (12%) were never, light, moderate, and heavy smokers, respectively. CSD was inversely associated with median PFS in a statistically significant dose-dependent manner (11.8 months (mo), 11.0 mo, 7.4 mo, and 3.9 mo; p < 0.001). Statistically significant negative association was observed between CSD and median OS (33.6 mo, 26.3 mo, 20 mo, and 8.9 mo; p < 0.001). In the multivariate analysis adjusted for age, sex, performance status, stage, and timing of EGFR-TKIs, CSD was an independent predictive factor for disease progression (hazard ratio [HR], 4.00; 95% confidence interval [CI], 1.95–8.23; p = 0.012) and OS (HR, 3.9; 95% CI, 1.84–8.28; p < 0.001).

Conclusion

CSD is an important predictive and prognostic factor in patients with EGFR-mutated lung adenocarcinoma, and associated smoking-related gene signatures might affect the outcomes.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4691-0) contains supplementary material, which is available to authorized users.

Updating the role of FDG PET/CT for evaluation of lung cancer manifesting in nonsolid nodules

PURPOSE

To assess the feasibility of using CT to correct specific uptake values (SUVs) for fluorodeoxyglucose (FDG) in patients with nonsolid nodules.

METHODS

Patients with FDG-PET/CT and thin-section CT were included in this pilot study. Thirty-five adenocarcinomas manifesting as nonsolid nodules were classified into two groups; 90-100% and 1-89% lepidic component. SUVmax was corrected based on the CT determination of the proportion of soft tissue component within the cancer (SUVatt).

RESULTS

Both SUVmax and SUVatt increased as the percentage of the lepidic component decreased. SUVmax and SUVatt were significantly different between the groups.

CONCLUSION

Extent of invasiveness of nonsolid cancers (as a marker of aggressiveness) can potentially be quantified by PET/CT using a correction method that accounts for the proportion of soft tissue within the tumor.

Radiomics signature: a biomarker for the preoperative discrimination of lung invasive adenocarcinoma manifesting as a ground-glass nodule

OBJECTIVES

To identify the radiomics signature allowing preoperative discrimination of lung invasive adenocarcinomas from non-invasive lesions manifesting as ground-glass nodules.

METHODS

This retrospective primary cohort study included 160 pathologically confirmed lung adenocarcinomas. Radiomics features were extracted from preoperative non-contrast CT images to build a radiomics signature. The predictive performance and calibration of the radiomics signature were evaluated using intra-cross (n=76), external non-contrast-enhanced CT (n=75) and contrast-enhanced CT (n=84) validation cohorts. The performance of radiomics signature and CT morphological and quantitative indices were compared.

RESULTS

355 three-dimensional radiomics features were extracted, and two features were identified as the best discriminators to build a radiomics signature. The radiomics signature showed a good ability to discriminate between invasive adenocarcinomas and non-invasive lesions with an accuracy of 86.3%, 90.8%, 84.0% and 88.1%, respectively, in the primary and validation cohorts. It remained an independent predictor after adjusting for traditional preoperative factors (odds ratio 1.87, p < 0.001) and demonstrated good calibration in all cohorts. It was a better independent predictor than CT morphology or mean CT value.

CONCLUSIONS

The radiomics signature showed good predictive performance in discriminating between invasive adenocarcinomas and non-invasive lesions. Being a non-invasive biomarker, it could assist in determining therapeutic strategies for lung adenocarcinoma.

KEY POINTS

• The radiomics signature was a non-invasive biomarker of lung invasive adenocarcinoma. • The radiomics signature outweighed CT morphological and quantitative indices. • A three-centre study showed that radiomics signature had good predictive performance.

Development and Validation of Web-Based Nomograms to Precisely Predict Conditional Risk of Site-Specific Recurrence for Patients With Completely Resected Non-small Cell Lung Cancer: A Multiinstitutional Study

BACKGROUND

There is currently no consensus regarding the optimal postoperative follow-up strategy for patients with completely resected non-small cell lung cancer (NSCLC). We aimed to develop web-based nomograms to precisely predict site-specific postoperative recurrence in patients with NSCLC and to guide individual surveillance strategies including when to follow up and what diagnostic tests to perform.

METHODS

We investigated the pattern of recurrence in a series of 2,017 patients with NSCLC (squamous cell carcinoma and nonlepidic invasive adenocarcinoma) who underwent complete surgical resection at Fudan University Shanghai Cancer Center (development cohort), and developed web-based clinicopathologic prediction models for conditional risk of site-specific recurrence based on Cox regression. The variables used in the analysis included sex, age, smoking history, tumor size, tumor histology, lymphovascular invasion, visceral pleural invasion, and pathologic TNM stage. A separate cohort of 3,308 patients with NSCLC from Shanghai Chest Hospital was used for external validation.

RESULTS

In the development cohort and the external validation cohort for the established nomograms to predict overall recurrence, thorax recurrence, abdomen recurrence, neck recurrence, brain recurrence, and bone recurrence, the C-statistics of Harrell et al were 0.743 and 0.748, 0.728 and 0.703, 0.760 and 0.749, 0.779 and 0.757, 0.787 and 0.784, and 0.777 and 0.739, respectively. The calibration plots showed optimal agreement between nomogram-predicted 3-year recurrence-free survival and actual 3-year recurrence-free survival.

CONCLUSIONS

These user-friendly nomograms can precisely predict site-specific recurrence in patients with completely resected NSCLC, based on clinicopathologic features. They may help physicians to make individual postoperative follow-up plans.

Effect of invasive mucinous adenocarcinoma on lung cancer-specific survival after surgical resection: a population-based study

Background

In 2015, the World Health Organization (WHO) announced a new classification of lung tumors. Mucinous bronchioloalveolar adenocarcinomas were reclassified as invasive mucinous adenocarcinomas (IMAs). Due to the rarity or this tumor type, conflicting clinical outcomes have been reported based on small patient numbers.

Methods

Patients diagnosed as primary lung nonmucinous adenocarcinoma (NMA) or IMA from 2000 to 2014 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. General features of each IMA were explored and the effect of histological characteristics on lung cancer-specific survival was analyzed in matched samples using the TNM staging system.

Results

The incidence of IMA among all primary lung cancer patients was 0.2% (1,783/1,154,742), and the incidence of IMA among patients with a primary resected lung adenocarcinoma was 1.5% (531/35,406). IMAs tended to be located in the lower lobe (P<0.001), be well differentiated (P<0.001), and be N0 (91.7% vs. 72.3%, P<0.001), T1 or T2 (P<0.001), and stage I tumors (P<0.001) when compared with NMAs. After matching by stages, a stratified Cox PH analysis revealed that the tumor histologic type (P=0.2) did not increase the risk of lung cancer-specific death, while advanced age (HR 1.03, P<0.001), male sex, and the need for radiation, pneumonectomy or sublobar resections increased the risk of cancer-specific death.

Conclusions

The histologic type of the tumor, whether IMA or not, did not affect lung cancer-specific survival times among patients with a primary M0 stage lung adenocarcinoma. When stratified by the TNM staging system, patents that required pneumonectomy, sublobar resection or radiation had shorter lung cancer-specific survival times.

Clinicopathological Characteristics and Mutations Driving Development of Early Lung Adenocarcinoma: Tumor Initiation and Progression

Lung cancer is the leading cause of cancer-related deaths worldwide, with lung adenocarcinoma representing the most common lung cancer subtype. Among all lung adenocarcinomas, the most prevalent subset develops via tumorigenesis and progression from atypical adenomatous hyperplasia (AAH) to adenocarcinoma in situ (AIS), to minimally invasive adenocarcinoma (MIA), to overt invasive adenocarcinoma with a lepidic pattern. This stepwise development is supported by the clinicopathological and molecular characteristics of these tumors. In the 2015 World Health Organization classification, AAH and AIS are both defined as preinvasive lesions, whereas MIA is identified as an early invasive adenocarcinoma that is not expected to recur if removed completely. Recent studies have examined the molecular features of lung adenocarcinoma tumorigenesis and progression. EGFR-mutated adenocarcinoma frequently develops via the multistep progression. Oncogene-induced senescence appears to decrease the frequency of the multistep progression in KRAS- or BRAF-mutated adenocarcinoma, whose tumor evolution may be associated with epigenetic alterations and kinase-inactive mutations. This review summarizes the current knowledge of tumorigenesis and tumor progression in early lung adenocarcinoma, with special focus on its clinicopathological characteristics and their associations with driver mutations (EGFR, KRAS, and BRAF) as well as on its molecular pathogenesis and progression.

Ground glass opacities: Imaging, pathology, and gene mutations

BACKGROUND

Lung cancer can be detected in its early stages with computed tomography (CT). Early lung adenocarcinoma often is displayed as ground glass opacity (GGO), an entity that has been well studied over the past decade. However, few studies have focused on the correlation between CT characteristics and pathologic subtype of GGO. We aimed to explore the correlation between CT characteristics, pathologic subtype, and gene mutation associated with GGO in an effort to aid in the treatment of lung adenocarcinoma.

METHODS

In this retrospective study, patients with GGO who underwent surgery in our institution between 2013 and 2016 were included. Patients were divided into 2 groups on the basis of CT characteristics: group 1, diameter <20 mm and solid component <50%; and group 2, diameter ≥20 mm or solid component ≥50%. Differences in pathologic subtype and gene mutation pattern between groups were compared using the χ² test. The correlation between pathologic subtype and epidermal growth factor receptor (EGFR) mutation was also tested using the χ² test.

RESULTS

A total of 1018 cases (408 in group 1, 610 in group 2) were included; of these, 544 were tested for the EGFR gene mutation. There was a significant difference in predominant subtype (P < .001) and all included subtypes (P = .044) between the groups. Of 59 cases with the pathologic subtype of micropapillary or solid, 57 were in group 2. The EGFR gene mutation rate was significantly higher in group 2 than group 1 (P < .001) and significantly correlated with pathologic subtype (P < .001); adenocarcinoma in situ was the lowest (31.4%) and papillary was the highest (85.7%). EGFR mutation subtype did not significantly differ between groups (P = .499).

CONCLUSIONS

CT characteristics of GGO significantly correlated with pathologic subtype and gene mutation rate. The EGFR mutation rate differed significantly among pathologic subtypes. GGOs with a diameter of <20 mm and with a solid component <50% seldom contain subtypes with poor prognosis (micropapillary and solid) and the EGFR mutation rate was significantly lower.

Classification and Pathology of Lung Cancer

Advancement in the understanding of lung tumor biology enables continued refinement of lung cancer classification, reflected in the recently introduced 2015 World Health Organization classification of lung cancer. In small biopsy or cytology specimens, special emphasis is placed on separating adenocarcinomas from the other lung cancers to effectively select tumors for targeted molecular testing. In resection specimens, adenocarcinomas are further classified based on architectural pattern to delineate tissue types of prognostic significance. Neuroendocrine tumors are divided into typical carcinoid, atypical carcinoid, small cell carcinoma, and large cell neuroendocrine carcinoma based on a combination of features, especially tumor cell proliferation rate.

Comprehensive Computed Tomography Radiomics Analysis of Lung Adenocarcinoma for Prognostication

BACKGROUND

In this era of personalized medicine, there is an expanded demand for advanced imaging biomarkers that reflect the biology of the whole tumor. Therefore, we investigated a large number of computed tomography-derived radiomics features along with demographics and pathology-related variables in patients with lung adenocarcinoma, correlating them with overall survival.

MATERIALS AND METHODS

Three hundred thirty-nine patients who underwent operation for lung adenocarcinoma were included. Analysis was performed using 161 radiomics features, demographic, and pathologic variables and correlated each with patient survival. Prognostic performance for survival was compared among three models: (a) using only clinicopathological data; (b) using only selected radiomics features; and (c) using both clinicopathological data and selected radiomics features.

RESULTS

At multivariate analysis, age, pN, tumor size, type of operation, histologic grade, maximum value of the outer 1/3 of the tumor, and size zone variance were statistically significant variables. In particular, maximum value of outer 1/3 of the tumor reflected tumor microenvironment, and size zone variance represented intratumor heterogeneity. Integration of 31 selected radiomics features with clinicopathological variables led to better discrimination performance.

CONCLUSION

Radiomics approach in lung adenocarcinoma enables utilization of the full potential of medical imaging and has potential to improve prognosis assessment in clinical oncology.

IMPLICATIONS FOR PRACTICE

Two radiomics features were prognostic for lung cancer survival at multivariate analysis: (a) maximum value of the outer one third of the tumor reflects the tumor microenvironment and (b) size zone variance represents the intratumor heterogeneity. Therefore, a radiomics approach in lung adenocarcinoma enables utilization of the full potential of medical imaging and could play a larger role in clinical oncology.

Cytomorphological features as predictors of epidermal growth factor receptor mutation status in lung adenocarcinoma

Background:

Epidermal growth factor receptor mutation-positive (EGFR-p) lung adenocarcinomas are sensitive to tyrosine kinase inhibitors. Although histopathological subtype is an independent predictor of mutation status, there is a paucity of data on the cytomorphological features correlating with the EGFR mutation status. Therefore, the aim of this study was to determine whether certain cytomorphological features correlate with EGFR mutation in lung adenocarcinoma.

Materials and Methods:

A retrospective analysis of 48 lung adenocarcinoma cases diagnosed on fine needle aspiration cytology with known EGFR mutation status was conducted. All cytology smears with cellblock sections were reviewed. The cytomorphological features including tumor pattern, stromal features, nuclear and cytoplasmic features, and tumor grade were evaluated. Clinicoradiological features such as age, sex, smoking, tumor size, clinical stage, metastases, and presence of mass, nodule, lymphadenopathy, pleural effusion, and clinical outcome were also assessed.

Results:

Of 48 cases, 19 were EGFR-p and 29 were negative. EGFR-p cases showed a positive and significant correlation with flat monolayered sheets and acini, mild nuclear atypia, fine chromatin and smooth nuclear margins and these tumors were well differentiated. EGFR-negative tumors were moderate to poorly differentiated with predominance of solid clusters, moderate to marked nuclear atypia, with irregular nuclear margins and coarse chromatin. Clinically, female sex, nonsmoking status, smaller tumor size, and good clinical outcome correlated with EGFR-p status.

Conclusion:

Certain cytomorphological features correlate with and may suggest EGFR mutation status in advanced lung adenocarcinoma in an appropriate clinical context.

A two-stage approach of gene network analysis for high-dimensional heterogeneous data

Gaussian graphical models have been widely used to construct gene regulatory networks from gene expression data. Most existing methods for Gaussian graphical models are designed to model homogeneous data, assuming a single Gaussian distribution. In practice, however, data may consist of gene expression studies with unknown confounding factors, such as study cohort, microarray platforms, experimental batches, which produce heterogeneous data, and hence lead to false positive edges or low detection power in resulting network, due to those unknown factors. To overcome this problem and improve the performance in constructing gene networks, we propose a two-stage approach to construct a gene network from heterogeneous data. The first stage is to perform a clustering analysis in order to assign samples to a few clusters where the samples in each cluster are approximately homogeneous, and the second stage is to conduct an integrative analysis of networks from each cluster. In particular, we first apply a model-based clustering method using the singular value decomposition for high-dimensional data, and then integrate the networks from each cluster using the integrative $\psi$-learning method. The proposed method is based on an equivalent measure of partial correlation coefficients in Gaussian graphical models, which is computed with a reduced conditional set and thus it is useful for high-dimensional data. We compare the proposed two-stage learning approach with some existing methods in various simulation settings, and demonstrate the robustness of the proposed method. Finally, it is applied to integrate multiple gene expression studies of lung adenocarcinoma to identify potential therapeutic targets and treatment biomarkers.

Acinar-Predominant Pattern Correlates With Poorer Prognosis in Invasive Mucinous Adenocarcinoma of the Lung

OBJECTIVES

Invasive mucinous adenocarcinoma (IMA) is a variant of lung adenocarcinoma with several growth patterns, such as lepidic acinar and papillary. However, to our knowledge, no study regarding prognostic and clinicopathologic aspects of IMAs with different growth patterns has been reported.

METHODS

Of 2,236 patients with primary lung adenocarcinoma, 16 were identified as having lepidic-predominant IMA and 10 as having acinar-predominant IMA. Data regarding the clinicopathologic characteristics, computed tomography (CT) features, and prognosis were collected.

RESULTS

No statistically significant difference was noted in sex, age, smoker proportion, and T classification between both groups. The proportion of lymph node metastasis was significantly higher in acinar-predominant IMA (P = .046). Both groups shared many signs in CT findings. Air bronchogram was a relatively specific sign for lepidic-predominant IMA. Survival analysis showed that acinar-predominant IMA had a poorer prognosis (P = .0294).

CONCLUSIONS

Lepidic-predominant and acinar-predominant IMA are two different subtypes of IMA. Acinar-predominant IMA is associated with lymph node metastasis and a poorer prognosis.

Benefits and Challenges of Lung Cancer Screening in Older Adults

PURPOSE

Lung cancer screening with low-dose computed tomography has been shown to significantly reduce lung cancer-related mortality in high-risk patients. However, patients diagnosed with lung cancer are typically older and often have multiple age- and smoking-related comorbidities. As a result, cancer screening in older adults remains a complex decision, requiring careful consideration of patients' risk characteristics and life expectancy to ensure that the benefits outweigh the risks of screening. In this review, we evaluate the evidence regarding lung cancer screening, with a focus on older patients.

METHODS

PubMed was searched to identify relevant studies evaluating the clinical outcomes of lung cancer screening. The key words used in our search included non-small cell lung cancer (NSCLC), screening, older, comorbidities, computed tomography, and survival. While we primarily looked for articles specific to older patients, we also focused on subgroup analysis in older patients in larger studies. Finally, we reviewed all relevant guidelines regarding lung cancer screening.

FINDINGS

Guidelines recommend that lung cancer screening be considered in adults aged 55 to 80 years who are at high risk based on smoking history (ie, 30-pack-year smoking history; having smoked within the past 15 years). Patients who fit these criteria have been shown to have a 20% reduction in lung cancer-related mortality with the use of low-dose computed tomography versus chest radiography. High rates of false-positive results and potential overdiagnoses were also observed. Therefore, screening is generally not recommended in adults with severe comorbidities or short life expectancy, who may experience limited benefit and higher risks with screening. However, several studies have shown a benefit with continued lung cancer screening with appropriate selection of older individuals at the highest risk and with the lowest comorbidities.

IMPLICATIONS

Older patients experience the highest risk for lung cancer incidence and mortality, and stand to be the most likely to benefit from lung cancer screening. However, careful consideration must be given to higher rates of false-positives and overdiagnosis in this population, as well as tolerability of surgery and competing risks for death from other causes. The appropriate selection of older individuals for lung cancer screening can be greatly optimized by using validated risk-based targeting.

Predictors of recurrence and survival of pathological T1N0M0 invasive adenocarcinoma following lobectomy

BACKGROUND

This retrospective research was designed to investigate the relationship between pT1N0M0 invasive adenocarcinoma (IADC) harboring solid (SOL) and/or micropapillary (MIP) components and its prognosis following lobectomy.

METHODS

Clinical data of pT1N0M0 IADC patients were retrospectively collected from Shanghai Chest Hospital. Survival curves were plotted by Kaplan-Meier methods. Multivariable cox regressions were conducted to discover the independent risk factors of recurrence-free survival (RFS) and overall survival (OS), through which nomograms were performed to visualize the risk of recurrences and outcomes in personalized information.

RESULTS

Totally, 1965 patients were enrolled, including 248 harboring SOL/MIP and 1717 not. IADC demonstrated worse 5-year RFS (81.9 vs. 92.2%, p < 0.001) and OS (85.7 vs. 94.4%, p < 0.001) when harboring SOL and/or MIP components. And this status became an independent factor associated with poorer RFS (HR 2.445, 95% CI 1.565-3.821, p < 0.001) and OS (HR 2.139, 95% CI 1.180-3.878, p = 0.012) instead of novel classification of IADC predominant patterns. No difference existed between SOL/MIP predominant and minor patterns. In addition, age > 60, smoking, post-chemotherapy and T1b were all indicating poorer RFS and smoking was also related with worse OS. The c-indexes of nomograms were 0.723 for RFS (95% CI, 0.662-0.784) and 0.703 for OS (95% CI, 0.629-0.777) respectively.

CONCLUSIONS

Once the pT1N0M0 IADC harboring SOL/MIP, it strongly indicated the worse clinical recurrence and survival outcome, no matter whether the SOL and/or MIP was predominant. Smoking was correlated with worse prognosis for those patients. Age > 60 and stage T1b also indicated poorer RFS. Whether post-chemotherapy was harmful to pT1N0M0 IADC patients needed further research.

Expression of PD-L1 correlates with pleomorphic morphology and histological patterns of non-small-cell lung carcinomas

AIMS

As immunomodulatory therapy is being integrated into treatment regimens for non-small-cell lung carcinoma, we aimed to prospectively collect data on the immunohistochemical profile of tumours assessed in our institution and to correlate this with morphological tumour features.

METHODS AND RESULTS

Immunohistochemistry for programmed death-ligand 1 (PD-L1) was considered to be adequate when >100 tumour cells were seen microscopically. When adequate, PD-L1 staining was scored as <1%, ≥1-49% or ≥50% positive membrane staining within tumour cells only. There were 197 assessable cases, of which 87% of those with pleomorphic features (n = 39) showed ≥50% positivity for PD-L1 expression, as compared with only 33% of cases without pleomorphic features (P < 0.05) (90% versus 25% in resected cases). Further correlation of PD-L1 expression with architectural patterns within the tumours was performed in 74 adenocarcinoma resections. All invasive mucinous adenocarcinomas scored <1%. All lepidic components in non-mucinous adenocarcinoma resections scored <1%. Thirty-five per cent of the acinar/papillary components and 53% of the solid/micropapillary components were positive for PD-L1 expression.

CONCLUSIONS

There are significant differences in PD-L1 expression in relation to histological patterns, with particularly high levels in those with pleomorphic features and low/undetectable levels in invasive mucinous adenocarcinomas and the lepidic components of non-mucinous adenocarcinomas. Assessment of PD-L1 expression in a resected adenocarcinoma with a lepidic component may therefore not be reliable when immumodulatory therapy for recurrent disease is being considered, and either re-biopsy or limiting assessment to the invasive component may be more appropriate.

Clinical Features of Ground Glass Opacity-Dominant Lung Cancer Exceeding 3.0 cm in the Whole Tumor Size

BACKGROUND

Ground glass opacity (GGO)-dominant lung adenocarcinoma sized 3.0 cm or less in the whole tumor size is widely known to have an excellent prognosis and is regarded as early lung cancer. However, the characteristics and prognosis of lung cancer showing GGO exceeding 3.0 cm remains unclear.

METHODS

From 2002 through 2012, we reviewed 3,735 lung cancers that underwent complete resection at our institution. We identified 160 lung cancers (4.3%) showing GGO exceeding 3.0 cm on thin-section computed tomography and divided them into three types by the consolidation/tumor ratio (CTR) using cutoff values of 0.25 and 0.5. We compared the characteristics and prognosis among these types.

RESULTS

Type A (CTR, 0 to ≤0.25), type B (CTR, >0.25 to ≤0.5), and type C (CTR, >0.5 to <1.0) were found in 16 (10%), 37 (23%), and 107 lesions (67%), respectively. No lymph node metastasis was found in types A and B. Recurrence was not observed in types A and B. The 5-year overall survival and disease-free survival rates were both 100% in type A, both 97.2% in type B, and 88.4% and 66.7% in type C, respectively. Patients with type C had a significantly worse prognosis than those with the other types with respect to overall survival and disease-free survival.

CONCLUSIONS

A patient with GGO-dominant lung cancer exceeding 3.0 cm can be considered to be in a group of patients with nodal-negative disease and an excellent prognosis.

Prognostic significance of stem cell-related marker expression and its correlation with histologic subtypes in lung adenocarcinoma

Cancer stem cells (CSCs) are a small subset of tumor cells that exhibit stem cell-like properties and contribute in treatment failure. To clarify the expression and prognostic significance of several CSC markers in non-small cell lung cancer, we retrospectively analyzed 368 patients with adenocarcinoma (n = 226) or squamous cell carcinoma (n = 142). We correlated the expression of six CSC markers – CD133, CD44, aldehyde dehydrogenase 1 (ALDH1), sex determining region Y-box 2 (SOX2), octamer binding transcription factor 4 (OCT4), and Nanog – with clinicopathologic and molecular variables and survival outcomes. In adenocarcinoma, CD133, ALDH1 and CD44 expression was associated with low pathologic stage and absence of lymphovascular invasion, while Nanog expression correlated with high histologic grade, lymphatic invasion and increased expression of Snail-1, a transcription factor associated with epithelial-mesenchymal transition. CSC marker expression was also associated with histologic subtypes in adenocarcinoma. Multivariate analysis showed that high Nanog expression was an independent factor associated with a poor prognosis in adenocarcinoma. CSC markers had no prognostic value in squamous cell carcinoma. These results suggest that Nanog is an independent negative prognostic factor that may be associated with epithelial-mesenchymal transition in lung adenocarcinoma.

Prognostic significance of histologic classification and tumor disappearance rate by computed tomography in lung cancer

Background

We investigated the prognostic value of the International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and assessed the relationship between pathologic invasiveness and tumor disappearance rate (TDR) in lung adenocarcinoma with ground-glass opacity (GGO).

Methods

We reviewed data from 202 consecutive patients operated on between 2000 and 2009 for clinical T1-2N0 lung adenocarcinoma with GGO and reclassified their histologic subtypes according to the IASLC/ATS/ERS classification. Thirty-nine patients had adenocarcinoma in situ (AIS), 29 minimally invasive adenocarcinoma (MIA), 75 lepidic predominant invasive adenocarcinoma (LPA), and 59 non-lepidic predominant invasive adenocarcinoma (NLPA). Survival outcomes were compared according to histologic subtype and TDR.

Results

The mean age was 58 years and 101 patients (50%) were male. Lobectomy was performed in 161 patients (79.7%), wedge resection in 34 (16.8%), and segmentectomy in 7 (3.5%). Patients with AIS, MIA, and LPA had significantly smaller tumor sizes, earlier pathologic T stages, and lower incidences of lymphatic/pleural invasion than those with NLPA. The 5-year recurrence-free survival (RFS) rates were 95.1%, 94.5%, and 87.6% in the AIS + MIA, LPA, and NLPA groups, respectively (P=0.029). Tumors with a TDR>75% were associated with lepidic predominant histologic subtype and less pathologic invasiveness. The 5-year RFS rates were 97.4% in tumors with a TDR >75% and 87.8% in tumors with a TDR ≤75% (P=0.0009).

Conclusions

Histologic subtype according to the IASLC/ATS/ERS classification and TDR both correlated with pathologic invasiveness and predicted survival in patients with lung adenocarcinoma with GGO.

Lepidic Predominant Pulmonary Lesions (LPL): CT-based Distinction From More Invasive Adenocarcinomas Using 3D Volumetric Density and First-order CT Texture Analysis

RATIONALE AND OBJECTIVES

This study aimed to differentiate pathologically defined lepidic predominant lesions (LPL) from more invasive adenocarcinomas (INV) using three-dimensional (3D) volumetric density and first-order texture histogram analysis of surgically excised stage 1 lung adenocarcinomas.

MATERIALS AND METHODS

This retrospective study was institutional review board approved and Health Insurance Portability and Accountability Act compliant. Sixty-four cases of pathologically proven stage 1 lung adenocarcinoma surgically resected between September 2006 and October 2015, including LPL (n = 43) and INV (n = 21), were evaluated using high-resolution computed tomography. Quantitative measurements included nodule volume, percent solid volume (% solid), and first-order texture histogram analysis including skewness, kurtosis, entropy, and mean nodule attenuation within each histogram quartile. Binomial logistic regression models were used to identify the best set of parameters distinguishing LPL from INV.

RESULTS

Univariate analysis of 3D volumetric density and histogram features was statistically significant between LPL and INV groups (P < .05). Accuracy of a binomial logistic model to discriminate LPL from INV based on size and % solid was 85.9%. With optimized probability cutoff, the model achieves 81% sensitivity, 76.7% specificity, and area under the receiver operating characteristic curve of 0.897 (95% confidence interval, 0.821-0.973). An additional model based on size and mean nodule attenuation of the third quartile (Hu_Q3) of the histogram achieved similar accuracy of 81.3% and area under the receiver operating characteristic curve of 0.877 (95% confidence interval, 0.790-0.964).

CONCLUSIONS

Both 3D volumetric density and first-order texture analysis of stage 1 lung adenocarcinoma allow differentiation of LPL from more invasive adenocarcinoma with overall accuracy of 85.9%-81.3%, based on multivariate analyses of either size and % solid or size and Hu_Q3, respectively.

Pathologic N0 Status in Clinical T1N0M0 Lung Adenocarcinoma is Predictable by the Solid Component Proportion with Quantitative CT Number Analysis

Correctly predicting pathologic regional node-negative (pN₀) disease in patients with lung cancer before operation may avoid unnecessary mediastinal lymph node dissection (MLND). In this study, we analyze the value of the radiographic and histopathological features of primary tumors for predicting pN₀ status in cT₁N₀M₀ lung adenocarcinoma and to establish an optimal surgical strategy for avoiding MLND in cT₁N₀M₀ lung adenocarcinoma patients. We retrospectively investigated the histopathological and radiographic data of 348 surgically resected cT₁N₀M₀ lung adenocarcinoma patients with systematic lymph node dissection from January 2005 to December 2012. Histopathological features and radiographic features were analyzed. Multivariable analysis was used to identify significant predictors of pN₀ disease. Our results showed that pN₀ disease was detected in 306 patients (87.9%) among the 348 patients with cT₁N₀M₀ lung adenocarcinoma. A decreasing trend of the pN₀ disease proportion was observed with both increasing histological grade and decreased differentiation (P < 0.001). In multivariable analysis, the solid component proportion was a significant predictor of pN₀ disease. Among 110 patients with a solid component proportion of no more than 21.3%, mediastinal lymph node involvement was not observed. Patients who meet this criterion may be successfully managed with lung resection without MLND.

Impact of Solid Minor Histologic Subtype in Postsurgical Prognosis of Stage I Lung Adenocarcinoma

BACKGROUND

Few studies focus on the outcome and effect of a postsurgical treatment strategy for early stage patients with minor solid components pattern. This study investigated the prognosis and the adjuvant chemotherapy benefit among stage I invasive lung adenocarcinoma patients with minor solid components pattern according to the eighth TNM staging classification.

METHODS

A total of 3,308 lung adenocarcinoma patients with mixed histologic components was divided into three groups: solid predominant, solid minor, and solid absent pattern. Disease-free survival and overall survival were analyzed to evaluate survival difference among patients in the different groups using the Kaplan-Meier approach and multivariable Cox models.

RESULTS

Both solid predominant and solid minor groups showed significantly worse disease-free survival (p < 0.001) and overall survival (p < 0.001) compared with the solid absent group. There were no significant disease-free survival (hazard ratio [HR] 1.41, 95% confidence interval [CI]: 0.87 to 2.30, p = 0.161) or overall survival (HR 1.60, 95% CI: 0.83 to 3.09, p = 0.159) difference between the former two groups. For patients in stage IB, adjuvant chemotherapy improves disease-free survival (HR 0.33, 95% CI: 0.11 to 1.02, p = 0.044) but not overall survival (HR 0.61, 95% CI: 0.21 to 1.77, p = 0.360) in the solid predominant group. No adjuvant chemotherapy benefits for disease-free survival (HR 1.04, 95% CI: 0.49 to 2.22; p = 0.922) and overall survival (HR 0.49, 95% CI: 0.13 to 1.90; p = 0.291) were seen for the solid minor group.

CONCLUSIONS

Solid minor components predict a significantly worse prognosis compared with the solid absent pattern. However, adjuvant chemotherapy may be unhelpful to improve outcomes for stage IB patients with solid minor components after surgery.

The maximum standardized uptake value of preoperative positron emission tomography/computed tomography in lung adenocarcinoma with a ground-glass opacity component of less than 30 mm

BACKGROUND AND OBJECTIVES

This study evaluated the relationship between the maximum standardized uptake value (SUVmax) of preoperative positron emission tomography/computed tomography (PET/CT) and the characteristics of lung adenocarcinoma featuring ground-glass opacity nodules (GGN).

METHODS

The association of the SUVmax of preoperative PET/CT with ground-glass opacity (GGO) proportion on CT, subtypes of adenocarcinoma (minimally invasive adenocarcinoma, invasive adenocarcinoma), predominant types of invasive adenocarcinoma, and size of the total and invasive components of pathology were evaluated in 190 patients who underwent resection for lung adenocarcinoma featuring GGN.

RESULTS

The mean SUVmax of non-solid GGN and partly solid GGN were 0.53 and 1.32, respectively (P = 0.029). The mean SUVmax of the main masses in 38 patients with MIA and 152 with invasive adenocarcinoma were 0.86 and 1.36, respectively (P = 0.029). The mean SUVmax of acinar, lepidic, papillary, and solid tumors were 1.61, 0.87, 0.98, and 1.60, respectively. The mean SUVmax of invasive components measuring ≤10 mm, 11-20 mm, and >20 mm were 0.84, 1.66, and 2.09, respectively (P < 0.001).

CONCLUSIONS

The SUVmax of lung adenocarcinoma featuring GGN can vary depending on the GGO proportion. A higher SUVmax can be expected in invasive adenocarcinoma than in MIA, and solid and acinar-predominant invasive adenocarcinoma showed a higher SUVmax.

Clinical characteristics and programmed cell death ligand-1 expression in adenocarcinoma in situ and minimally invasive adenocarcinoma of lung

Objectives

According to the IASLC/ATS/ERS 2011 classification, there are two new conceptions of lung adenocarcinoma, adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), which are very early stages of lung adenocarcinoma. This study aimed to analyze clinical features of AIS and MIA and determine the expression profile of PD-L1 in AIS and MIA.

Results

In all 274 patients, 77 were diagnosed as AIS and 197 as MIA. We accidentally found 4 patients with recurrence, which were all MIA. The median age of the patients at diagnosis was both 52 years. 71.4% were female in AIS as while as 71.1% in MIA. 36.4% patients were observed with ever symptoms in AIS and 28.9% in MIA. 12.9% and 8.6% had smoking history respectively in AIS an MIA. All AIS and MIA cases were PD-L1 negative. There was significant association between symptoms and more mild progression of nodules in chest CT before surgery.

Materials and Methods

We analyzed some clinical features of 274 patients including age, sex, smoking history, family history, surgery, EGFR mutation, ALK, ROS-1, serum CEA level et al. The expression of PD-L1 was evaluated by immunohistochemical analysis in 37 specimens of MIA and 17 specimens of AIS.

Conclusions

There are no significant differences between AIS and MIA in clinical features. AIS and MIA almost do not express PD-L1 protein and without any lymph node metastasis. The surgery intervention is supposed to be as small as possible.

Risk factors of lymph node metastasis in patients with non-small cell lung cancer ≤ 2 cm in size: A monocentric population-based analysis

Aim

This study was designed to determine the risk factors of lymph node metastasis in non‐small cell lung cancer (NSCLC) patients with tumors ≤ 2 cm, using the Shanghai Chest Hospital Lung Cancer Database.

Methods

Five hundred and eighteen patients with NSCLC ≤ 2 cm were included in this study, and were classified into lymph node‐positive and lymph node‐negative groups. Univariate and multivariate logistic regression analyses were performed to select the independent risk factors for lymph node metastasis in NSCLC patients.

Results

No evidence of metastasis was found in tumors ≤ 1 cm, all positive results were in tumors sized 1–2 cm. Imaging characteristics, including solid and part‐solid nodules, were strongly associated with lymph node metastasis (odds ratio [OR] 24.959, 95% confidence interval [CI] 5.999–103.835, P < 0.001; OR 12.559, 95% CI 3.564–44.259, P < 0.001) and subgroup logistic analysis (OR 21.384, 95% CI 5.058–90.407, P < 0.001; OR 11.632, 95% CI 3.290–41.126, P < 0.001). Greater lymph node metastasis was observed in non‐adeno non‐squamous carcinoma. The presence of pleural invasion and carcinoembryonic antigen levels indicated lymph node dissection. Similar results were revealed in subgroup analysis in tumors ≤ 2 to > 1 cm.

Conclusion

Size had a great impact on lymph node metastasis, especially tumors of 1–2 cm. Preoperative imaging, non‐adeno non‐squamous carcinoma, pleural invasion, and carcinoembryonic antigen all indicated lymph node dissection. There was no discrepancy between N1 and N2 positive lymph nodes.