Histopathological subtyping is a prognostic factor in stage IV lung adenocarcinoma

Spread Through Air Spaces in Stage I to III Resected Lung Adenocarcinomas: Should the Presence of Spread Through Air Spaces Lead to an Upstaging?

In recent years, the concept of spread through air spaces (STAS) has been discussed as an adverse prognostic factor for lung cancer. The aim of our study is to clarify the prognostic role of STAS in relation to the main recognized prognostic factors in a retrospective cohort of 330 European patients who underwent stages I to III lung adenocarcinoma resection. On univariate analysis, the presence of STAS was related to progression-free survival (PFS; hazard ratio [HR]: 1.48; 95% CI: 1.02-2.19; P = 0.038) and overall survival (OS; HR: 1.61; 95% CI: 1.03-2.52; P = 0.50). On multivariate analysis, STAS was related to PFS (HR: 1.51; 95% CI: 1.00-2.17; P = 0.050) and to OS (HR: 1.67; 95% CI: 1.00-2.81; P = 0.050). We showed that the presence of STAS was associated with lower PFS, equivalent to the next pathologic T stage, especially the median PFS of T3 stages without STAS was at 62.8 months while the median PFS of T3 stages with STAS was at 15.7 months, closer to the median PFS of 17.4 months in T4 stages. To conclude, STAS is an independent prognostic factor of PFS in this European cohort and is close to significance for OS. We suggest that the presence of STAS might lead to an upstaging of lung adenocarcinoma.

Multi-classification model incorporating radiomics and clinic-radiological features for predicting invasiveness and differentiation of pulmonary adenocarcinoma nodules

PURPOSE

To develop a comprehensive multi-classification model that combines radiomics and clinic-radiological features to accurately predict the invasiveness and differentiation of pulmonary adenocarcinoma nodules.

METHODS

A retrospective analysis was conducted on a cohort comprising 500 patients diagnosed with lung adenocarcinoma between January 2020 and December 2022. The dataset included preoperative CT images and histological reports of adenocarcinoma in situ (AIS, n = 97), minimally invasive adenocarcinoma (MIA, n = 139), and invasive adenocarcinoma (IAC, n = 264) with well-differentiated (WIAC, n = 99), moderately differentiated (MIAC, n = 84), and poorly differentiated IAC (PIAC, n = 81). The patients were classified into two groups (IAC and non-IAC) for binary classification and further divided into three and five groups for multi-classification. Feature selection was performed using the least absolute shrinkage and selection operator (LASSO) algorithm to identify the most informative radiomics and clinic-radiological features. Eight machine learning (ML) models were developed using these features, and their performance was evaluated using accuracy (ACC) and the area under the receiver-operating characteristic curve (AUC).

RESULTS

The combined model, utilizing the support vector machine (SVM) algorithm, demonstrated improved performance in the testing cohort, achieving an AUC of 0.942 and an ACC of 0.894 for the two-classification task. For the three- and five-classification tasks, the combined model employing the one versus one strategy of SVM (SVM-OVO) outperformed other models, with ACC values of 0.767 and 0.607, respectively. The AUC values for histological subtypes ranged from 0.787 to 0.929 in the testing cohort, while the Macro-AUC and Micro-AUC of the multi-classification models ranged from 0.858 to 0.896.

CONCLUSIONS

A multi-classification radiomics model combined with clinic-radiological features, using the SVM-OVO algorithm, holds promise for accurately predicting the histological characteristics of pulmonary adenocarcinoma nodules, which contributes to personalized treatment strategies for patients with lung adenocarcinoma.

Correlation of Programmed Death-Ligand 1 Expression With Lung Adenocarcinoma Histologic and Molecular Subgroups in Primary and Metastatic Sites

Programmed death-ligand 1 (PD-L1) expression in terms of the tumor proportion score (TPS) is the main predictive biomarker approved for immunotherapy against lung nonsmall cell carcinoma. Although some studies have explored the associations between histology and PD-L1 expression in pulmonary adenocarcinoma, they have been limited in sample size and/or extent of examined histologic variables, which may have resulted in conflicting information. In this observational retrospective study, we identified primary and metastatic lung adenocarcinoma cases in the span of 5 years and tabulated the detailed histopathologic features, including pathological stage, tumor growth pattern, tumor grade, lymphovascular and pleural invasion, molecular alterations, and the associated PD-L1 expression for each case. Statistical analyses were performed to detect associations between PD-L1 and these features. Among 1658 cases, 643 were primary tumor resections, 751 were primary tumor biopsies, and 264 were metastatic site biopsies or resections. Higher TPS significantly correlated with high-grade growth patterns, grade 3 tumors, higher T and N stage, presence of lymphovascular invasion, and presence of MET and TP53 alterations, whereas lower TPS correlated with lower-grade tumors and presence of EGFR alterations. There was no difference in PD-L1 expression in matched primary and metastases, although higher TPS was observed in metastatic tumors due to the presence of high-grade patterns in these specimens. TPS showed a strong association with a histologic pattern. Higher-grade tumors had higher TPS, which is also associated with more aggressive histologic features. Tumor grade should be kept in mind when selecting cases and blocks for PD-L1 testing.

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.

Anti-CK7/CK20 Immunohistochemistry Did Not Associate with the Metastatic Site in TTF-1-Negative Lung Cancer

Anti-CK7 and anti-CK20 immunohistochemistry is sometimes used to establish a diagnosis of primary lung cancer. We performed a retrospective study on the value of anti-CK7 and anti-CK20 immunohistochemistry in 359 biopsies of patients with suspected lung carcinoma in order to assess the usefulness of these antibodies in the evaluation of lung tumors in biopsies. Our results showed TTF-1 positivity in 73.3% of patients. EGFR mutations and ALK rearrangements were significantly different between TTF-1 positive and TTF-1 negative tumors (p < 0.001 and p = 0.023, respectively). Our results show a significant difference (p < 0.001) between TTF-1 positive and TTF-1 negative carcinomas with a median survival of 21.97 months (CI95% = 17.48−30.9 months) and 6.52 months (CI95% = 3.34−10.3 months), respectively. In the group of TTF-1 negative patients, anti-CK7 and CK20 immunohistochemistry was performed in 70 patients and showed CK7+/CK20- staining in 61 patients (87.1%), CK7-/CK20- in 4 patients (5.7%), CK7+/CK20+ in 3 patients (4.3%), and CK7-/CK20- in 2 patients (2.8%). No specific or molecular pattern was found in these groups of CK7/CK20 combinations. In total, this work brings arguments concerning the uselessness of anti-CK7/CK20 immunohistochemistry in the case of suspicion of primary lung cancer in biopsies.

PSC subtyping based on TTF-1 and p40 expression reveals distinct molecular characteristics and therapeutic strategies

Pulmonary sarcomatoid carcinoma (PSC) is a unique form of poorly differentiated non-small cell lung cancer (NSCLC) and is notorious for its highly malignant nature and dismal prognosis. To introduce effective treatment for PSC patients, precise subtyping of PSC is demanding. In our study, TTF-1 and P40 immunohistochemistry (IHC) staining were applied to 56 PSC patients with multi-omics data. According to IHC results, we categorized these patients into three subgroups and profiled their molecular contexture using bioinformatic skills. IHC results classified these patients into three subgroups: TTF-1 positive subgroup (n=27), P40 positive subgroup (n=15), and double-negative subgroup (n=14). Spindle cell samples accounted for 35.71% (5/14) of double-negative patients, higher than others (p=0.034). The three subgroups were heterogeneous in the genomic alteration spectrum, showing significant differences in the RTK/RAS pathway (p=0.004) and the cell cycle pathway (p=0.030). The methylation profile of the double-negative subgroup was between the other two subgroups. In similarity analysis, the TTF-1 and p40 subgroups were closely related to LUAD and LUSC, respectively. The TTF-1 positive subgroup had the highest leukocyte fraction (LF) among several cancer types, and the tumor mutation burden (TMB) of the p40 positive subgroup ranked third in the TMB list, suggesting the applicability of immunotherapy for PSC. The study established a new subtyping method of PSC based on IHC results and reveals 3 subgroups with distinct molecular features, providing evidence for refined stratification in the treatment of PSC. This article is protected by copyright. All rights reserved.

WHO grading system for invasive pulmonary lung adenocarcinoma reveals distinct molecular signature: An analysis from the cancer genome atlas database

Lung adenocarcinoma grading has gained interest in the past years. Recently a three-tier tumor grading was proposed showing that it is related to patients' prognosis. Nevertheless, the underlying molecular basis of this morphological grading remains partly unknown. The aim of our work is to take advantage of The Cancer Genome Atlas lung adenocarcinoma (TCGA_LUAD) cohort to describe the molecular data associated to tumor grading. We performed a study on publicly available data of the TCGA database first by assessing a tumor grade on downloadable tumor slides. Secondly we analyzed the molecular features of each tumor grade group. Our work was performed on a study group of 449 patients. We show that aneuploidy score was significantly different between grade 2 and grade 3 groups with different chromosomal imbalance (p < 0.001). SCGB1A1 mRNA expression was higher in grade 2 (p = 0.0179) whereas NUP155, CHFR, POLQ and CDC7 have a higher expression in grade 3 (p = 0.0189, 0.0427, 0.0427 and 0.427 respectively). GZMB and KRT80 have a higher methylation of DNA in grade 2 (p = 0.0201 and 0.0359 respectively). MT1G, CLEC12B and NDUFA7 have a higher methylation of DNA in grade 3 (p < 0.001, 0.0246 and 0.0359 respectively). We showed that the number of activated pathways is different between grade 2 and grade 3 patients (p = 0.004). We showed that differentially expressed genes by mRNA analysis and DNA methylation analysis involve several genes implied in chemoresistance. This could suggest that grade 3 lung adenocarcinoma might be more resistant to chemotherapy.

[Multiple synchronous lung adenocarcinoma: Interest of molecular biology for staging]

INTRODUCTION

The presence of multiple synchronous lung tumors is not a rare event. Distinguishing intra-pulmonary metastases from multiple synchronous lung adenocarcinoma is a challenge for pathologists and physicians. We present observation of a patient with three lung tumors corresponding to three adenocarcinomas for which molecular analysis had a significant impact on tumor staging.

OBSERVATION

Three suspect lesions were discovered in a 61-year-old patient, a smoker, in each lobe of the right lung. Right pneumonectomy with lymph node dissection was performed. Pathological examination showed that each tumor was in fact an adenocarcinoma. In order to more precisely indicate tumor staging, molecular analysis was performed with next generation sequencing showing a different point mutation in a driver gene on each tumor. The final diagnosis is that the three tumors are distinct synchronous tumors, which must be staged separately.

CONCLUSIONS

In modern-day practice of thoracic oncology and of surgical pathology, molecular biology represents a complement for tumor staging in the event of multiple lung tumors.

Recommendations for immunocytochemistry in lung cancer typing: An update on a resource-efficient approach with large-scale comparative Bayesian analysis

OBJECTIVES

The majority of lung cancer cases are of advanced stage and diagnosis is usually made using minimally invasive small biopsies and cytological specimens. The WHO 2015 classification recommends limiting immunocytochemistry (ICC) to lung cancer typing and molecular testing drives for personalised therapies. An algorithm using Bayes' theorem could be useful for defining antibody profiles. This study aims to assess the impact of different antibody profiles for cytological samples on the accuracy of lung cancer typing with a large-scale Bayesian analysis.

METHODS

A retrospective examination of 3419 consecutive smears and/or cytospins diagnosed over 2011-2016 found 1960 primary lung cancer tumours: 972 adenocarcinomas (ADC), 256 squamous carcinomas (SQC), 268 neuroendocrine tumours (NET), and 464 non-small cell cancer-not otherwise specified (NSCC-NOS). The a priori and a posteriori probabilities, before and after ICC using antibodies singly or in combination, were calculated for different lung cancer types.

RESULTS

TTF-1 or CK7 alone improved the a posteriori probabilities of correct cytological typing for ADC to 86.5% and 95.8%, respectively. For SQC, using p40 (∆Np63) or CK5/6 together with CK5/14 led to comparable results (78.3% and 90.3%). With synaptophysin or CD56 alone, improvements in a posteriori probabilities to 87.5 and 90.3% for the correct recognition of NET could be achieved.

CONCLUSIONS

Based on morphological and clinical data, the use of two antibodies appears sufficient for reliable detection of the different lung cancer types. This applies to diagnoses that were finalised following ICC both on a clinical or cytological basis and on a histological basis.

Prognostic value of Thyroid Transcription Factor-1 expression in lung adenocarcinoma in patients treated with anti PD-1/PD-L1

Anti-PD1/PD-L1-directed immune checkpoint inhibitors are game changers in advanced non-small-cell lung cancer, but biomarkers are lacking. The aim of our study was to find clinically relevant biomarkers of the efficacy of ICI in non-squamous NSCLC. We conducted a retrospective study of patients receiving ICI for advanced non squamous NSCLC in two cohorts. For a subset of patients, RNAseq data were generated on tumor biopsy taken before ICI. The primary end point was progression-free survival under ICI. Secondary end point was overall survival from ICI initiation. In the cohort, we studied 231 patients. Clinico-pathological characteristics included KRAS mutant status (n = 88), TTF1-positive expression (n = 136), LIPI (Lung Immune Prognostic Index) score of 0 (n = 116). In our cohort, lack of TTF1 expression, LIPI score >0, line of treatment >1, and liver metastases were associated with poorer PFS. TTF1 and PD-L1 status could be used to stratify survival and improve the AUC for prediction of prognosis in comparison with the PD-L1 gold standard. Using an external cohort of 154 patients, we confirmed the independent prognostic role of TTF1. TTF1 expression and PD-L1 can be used to stratify risk and predict PFS and OS in patients treated with ICI for NS-NSCLC.

Deep learning for predicting subtype classification and survival of lung adenocarcinoma on computed tomography

OBJECTIVES

The subtype classification of lung adenocarcinoma is important for treatment decision. This study aimed to investigate the deep learning and radiomics networks for predicting histologic subtype classification and survival of lung adenocarcinoma diagnosed through computed tomography (CT) images.

METHODS

A dataset of 1222 patients with lung adenocarcinoma were retrospectively enrolled from three medical institutions. The anonymised preoperative CT images and pathological labels of atypical adenomatous hyperplasia, adenocarcinoma in situ, minimally invasive adenocarcinoma, invasive adenocarcinoma (IAC) with five predominant components were obtained. These pathological labels were divided into 2-category classification (IAC; non-IAC), 3-category and 8-category. We modeled the classification task of histological subtypes based on modified ResNet-34 deep learning network, radiomics strategies and deep radiomics combined algorithm. Then we established the prognostic models in lung adenocarcinoma patients with survival outcomes. The accuracy (ACC), area under ROC curves (AUCs) and C-index were primarily performed to evaluate the algorithms.

RESULTS

This study included a training set (n = 802) and two validation cohorts (internal, n = 196; external, n = 224). The ACC of deep radiomics algorithm in internal validation achieved 0.8776, 0.8061 in the 2-category, 3-category classification, respectively. Even in 8 classifications, the AUC ranged from 0.739 to 0.940 in internal set. Further, we constructed a prognosis model that C-index was 0.892(95% CI: 0.846-0.937) in internal validation set.

CONCLUSIONS

The automated deep radiomics based triage system has achieved the great performance in the subtype classification and survival predictability in patients with CT-detected lung adenocarcinoma nodules, providing the clinical guide for treatment strategies.

Histopathologic and molecular profiling of lung adenocarcinoma skin metastases reveals specific features

AIMS

Little is known regarding the histopathological and molecular features of lung adenocarcinoma skin metastases. Our study is the largest to comprehensively explore these to date.

METHODS AND RESULTS

We performed a retrospective cohort study analysing 42 lung adenocarcinoma skin metastasis samples obtained from a database of 2659 lung adenocarcinomas collected between 2010 to 2020. EGFR exon 19 deletion was detected in one patient, and KRAS mutations were detected in 12 (33.3%) patients. The PD-L1 tumour proportion score was <1% in 27 patients, ≥1% and <50% in 8 patients, ≥50% in 6 patients, and not assessable in one patient. We showed that the predominant histopathologic subtype is different from that at other metastatic sites (p=0.024). TTF-1 was more often negative in skin metastases compared to other sites (p<0.001). The EGFR mutation rate tended to be lower for skin metastases compared to other sites (p=0.079). Skin metastases were associated with a high rate of PD-L1-negative cases (p=0.022).

CONCLUSION

Our work shows that the skin metastases of lung adenocarcinoma have a specific histopathologic profile.

Adenocarcinoma of High-Grade Patterns Associated with Distinct Outcome of First-Line Chemotherapy or EGFR-TKIs in Patients of Relapsed Lung Cancer

Purpose

High-grade patterns (micropapillary/solid/complex gland) are associated with a higher recurrence rate and shorter disease-free survival. Thus far, it remains unclear whether the efficacy of first-line anticancer therapy is different from that of the other adenocarcinoma subgroups for patients with high-grade patterns. The study aimed to investigate the association between an adenocarcinoma with high-grade patterns with the outcomes of first-line treatment in patients with lung cancer.

Patients and Methods

Patients with a high-grade pattern adenocarcinoma (more than 20% of micropapillary/solid components/complex glandular patterns) were retrospectively analyzed between June 2015 and June 2017. Patients’ clinical characteristics and treatment outcomes were compared with those of the remaining control adenocarcinoma subgroups.

Results

In total, 239 patients with adenocarcinoma, including 115 (48.1%) high-grade patterns and 124 (51.9%) control groups, were enrolled. Patients’ clinical characteristics such as age, sex, smoking status, and stage were similar between the two groups. Among them, 108 patients received first-line chemotherapy, and 131 received epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR-TKIs). In the chemotherapy group, adenocarcinoma of high-grade patterns had a significantly lower objective response rate (ORR; 15.6% vs 36.4%, P=0.045), shorter progression-free survival (PFS; median 4.1 vs 5.4 months, P=0.007) and overall survival (OS, median 19.6 vs 23.8 months, P=0.048) compared with the control group. As for these treated with EGFR-TKIs, a similar ORR (70.7% vs 72.1%, P=0.703), PFS (median 11.3 vs 13.9 months, P=0.065) and OS (median 34.1 vs 29.6%, p=0.575) were observed between these two groups.

Conclusion

An adenocarcinoma with high-grade patterns is associated with inferior outcomes to first-line chemotherapy in relapsed lung cancer. Patients who received chemotherapy had a significantly shorter PFS and OS and lower ORR than control subjects, while there was no difference in the EGFR-TKI cohort. This study is the first to report the distribution of adenocarcinoma with high-grade patterns.

Histopathological typing in diffuse malignant epithelioid mesothelioma: implication for prognosis and molecular basis

The prognostic impact of tumour grading, cytological and architectural patterns and stromal features in diffuse pleural malignant epithelioid mesothelioma (MEM) has been partly studied but not correlated to molecular features. We performed a retrospective study on 92 MEM in our department in order to assess the prognostic role of architectural and stromal patterns, especially tumour to stroma ratio. Secondly, based on The Cancer Genome Atlas (TCGA) database, we analysed the differentially expressed genes in prognostic groups of interest. Our results showed that tumour grading, tumour to stroma ratio and predominant pattern were related to overall survival, p≤0.001, p=0.01 and p=0.001, respectively. In univariate analysis, for high grade tumours hazard ratio (HR) was 4.75 (2.47-9.16), for stroma poor tumours HR=0.016, for predominant tubular or tubulopapillary pattern HR=0.044. In multivariate analysis, high grade tumours were related to overall survival [HR=3.09 (1.50-6.35), p=0.002] and predominant tubular or tubulopapillary pattern [HR=0.56 (0.32-0.99), p=0.045]. In TCGA analysis, after grading of diagnostic slides, we showed that KRTDAP and CXRCR1 expression was higher in low grade tumours, unlike PDZD7 and GPR176 expression which was higher in high grade tumours. FAM81B had a higher expression in stroma poor tumours. We did not find any differentially expressed genes in the architectural patterns group. Our work suggests that tumour grading is an important parameter in MEM with an underlying genomic basis. The role of tumour to stroma ratio needs to be investigated and might also have a genomic basis.

Heterogeneity of PD-L1 expression in lung adenocarcinoma metastasis is related to histopathological subtypes

OBJECTIVES

The heterogeneity of PD-L1 expression and its relationship with histopathological subtype has recently been shown on primary tumor but has not been evaluated on metastases. The aim of our work is to analyze PD-L1 expression within each histopathological pattern on resected metastases.

MATERIAL AND METHODS

136 patients were included in this retrospective study. Immunohistochemistry was performed with 22C3 laboratory-developed test. The Tumor Proportion Score was evaluated on each subtype.

RESULTS

The most frequent major histopathological subtype was solid (n = 69, 50.7 %), followed by acinar (n = 37, 27.2 %), micropapillary (n = 14, 10.3 %) and papillary (n = 10, 7.3 %). Mean percentage of PD-L1 expression for each subtype was at 28+/-4.8 % for solid subtype, 5.3+/-1.9 % for acinar subtype, 5+/-1.9 % for papillary subtype and 23.6+/-4.1 % for micropapillary subtype. Mean percentage of PD-L1 expression was different between solid pattern and acinar pattern (p < 0.001), solid pattern and papillary pattern (p = 0.007), micropapillary pattern and acinar pattern (p < 0.001) and micropapillary pattern and papillary pattern (p = 0.015).

CONCLUSION

To conclude, we have showed firstly that several patterns are present in metastases of lung adenocarcinoma, secondly that the evaluation of patterns and PD-L1 stain on different patterns is reproducible, thirdly that pattern heterogeneity is related to PD-L1 staining, fourthly that in metastatic lung adenocarcinoma with at least two patterns, solid and micropapillary subtypes have higher levels of PD-L staining, fifthly that PD-L1 heterogeneity between different patterns is not a rare event. These results might explain discrepancies of PD-L1 results between biopsies and surgical samples and the fact that some patients might respond to checkpoint inhibitors even though PD-L1 expression is low or absent.

PD-L1 Expression in Chinese Patients with Advanced Non-Small Cell Lung Cancer (NSCLC): A Multi-Center Retrospective Observational Study

Objective: This study aimed to investigate the prevalence of tumor programmed death-ligand 1 (PD-L1) expression in Chinese patients with advanced Non-Small Cell Lung Cancer (NSCLC). Methods: Tumor tissues with histologically confirmed stage IIIB/IV NSCLC were retrospectively obtained from 10 centers in China. PD-L1 expression was determined using the PD-L1 IHC 22C3 pharmDx kit (Agilent, Santa Clara, CA, USA) and the samples were repetitively assayed with the PD-L1 IHC 22C3 Ab concentrate (Agilent, Santa Clara, CA, USA). Results: Out of 901 patients who met the inclusion criteria, 879 (97.6%) had evaluable PD-L1 data. The number of patients with a PD-L1 tumor proportion score (TPS) < 1%, 1-49%, and ≥ 50% (corresponding to PD-L1 non-expression, low expression, and high expression) was 424 (48.2%), 266 (30.3%), and 189 (21.5%), respectively. PD-L1 expression was more likely to be found in patients younger than 75 years, men, current or former smokers, those with good performance status (PS) scores, and those with a wild-type epidermal growth factor receptor (EGFR). PD-L1 TPS ≥ 50% and ≥ 1% were respectively 28.0% and 50.2% among patients negative for both EGFR mutation and anaplastic lymphoma kinase (ALK) rearrangement. PD-L1 expression determined using the 22C3 antibody concentrate and pharmDx kit had comparable results. Conclusions: The prevalence of PD‑L1 expression in advanced NSCLC was consistent with that reported in the global EXPRESS study. Age, gender, smoking history, PS scores, and EGFR/ALK mutation status affected PD-L1 expression. The 22C3 antibody concentrate appears to be an alternative reagent for the PD-L1 assay.

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.