Relationship of Lymph Node Micrometastasis and Micropapillary Component and Their Joint Influence on Prognosis of Patients With Stage I Lung Adenocarcinoma

The value of T2-weighted MRI contrast ratio combined with DWI in evaluating the pathological grade of solid lung adenocarcinoma

AIM

To assess the predictive value of T2-weighted (T2W) magnetic resonance imaging (MRI) in combination with diffusion-weighted imaging (DWI) for determining the pathological grading of solid lung adenocarcinoma.

MATERIALS AND METHODS

The clinical and imaging data from 153 cases of solid lung adenocarcinoma (82 men, 71 women, mean age 63.2 years) confirmed at histopathology in The First Affiliated Hospital of Xi'an Jiaotong University from January 2017 to May 2022 were analysed retrospectively. Adenocarcinomas were classified into low-grade (G1 and G2) and high-grade (G3) groups following the 2020 pathological grading system proposed by the International Association for the Study of Lung Cancer. The T2-weighted contrast ratio (T2CR), calculated as the T2 signal intensity of the lung mass/nodule divided by the T2 signal intensity of the right rhomboid muscle was utilised. Two experienced radiologists reviewed the MRI images independently, measured the T2CR, and obtained apparent diffusion coefficient (ADC) values. The Mann-Whitney U-test was used to compare general characteristics (sex, age, maximum diameter), T2CR, and ADC values between the low-grade and high-grade groups. The non-parametric Kruskal-Wallis test determined differences in T2CR and ADC values among the five adenocarcinoma subtypes. Receiver characteristic curve (ROC) analysis, along with area under the curve (AUC) calculation, assessed the effectiveness of each parameter in distinguishing the pathological grade of lung adenocarcinoma. A Z-test was used to compare the AUC values.

RESULTS

Among the 153 patients with adenocarcinoma, 103 had low-grade adenocarcinoma, and 50 had high-grade adenocarcinoma. The agreement between T2CR and ADC observers was good (0.948 and 0.929, respectively). None of the parameters followed a normal distribution (p<0.05). The ADC value was lower in the high-grade adenocarcinoma group compared to the low-grade adenocarcinoma group (p=0.004), while the T2CR value was higher in the high-grade group (p=0.011). Statistically significant differences were observed in maximum diameter and gender between the two groups (p<0.001 and p=0.005, respectively), while no significant differences were noted in age (p=0.980). Among the five adenocarcinoma subtypes, only the lepidic and micropapillary subtypes displayed statistical differences in ADC values (p=0.047), with the remaining subtypes showing no statistical differences (p>0.05). The AUC values for distinguishing high-grade adenocarcinoma from low-grade adenocarcinoma were 0.645 for ADC and 0.627 for T2CR. Combining T2CR, ADC, sex, and maximum diameter resulted in an AUC of 0.778, sensitivity of 70%, and specificity of 75%. This combination significantly improved diagnostic efficiency compared to T2CR and ADC alone (p=0.008, z = 2.624; p=0.007, z = 2.679).

CONCLUSION

The MRI quantitative parameters are useful for distinguishing the pathological grades of solid lung adenocarcinoma, offering valuable insights for precise lung cancer treatment.

Spread Through Air Spaces in Residual Tumor Classification for Clinical IA Lung Adenocarcinoma

BACKGROUND

We aimed to validate the prognostic implication of uncertain resection, R(un), proposed by International Association for the Study of Lung Cancer (IASLC) and evaluate the prognostic value of spread through air spaces (STAS) in reclassifying the R classification among patients with lung adenocarcinoma after segmentectomy.

METHODS

We enrolled 1007 patients who underwent segmentectomy for c-stage IA lung adenocarcinoma between 2014 and 2017. Recurrence-free survival (RFS) and overall survival (OS) were compared to evaluate the prognostic value of IASLC-R(un) and STAS. Whether STAS would skip into complementary lobectomy was evaluated in a prospective cohort.

RESULTS

The current IASLC-R(un) failed to significantly stratify the RFS (P = .078) in segmentectomy, and STAS was a stronger risk factor of poor prognosis for both RFS and OS (P < .001). Moreover, the presence of STAS was associated with increased locoregional recurrence in patients undergoing segmentectomy (P < .001) but not in those treated with lobectomy (P = .187), indicating that only STAS-positive segmentectomy was consistent with the concept of R(un) in relapse pattern. After reclassifying STAS-positive segmentectomy into the R(un) category, the proposed R(un) showed an improvement in prognosis stratification. In addition, 2 of 30 patients (6.2%) in the prospective cohort who underwent initial segmentectomy and complementary lobectomy had STAS clusters in the complementary lobectomy specimens.

CONCLUSIONS

Unfavorable prognosis, relapse patterns consistent with R(un), and pathologic verification that saltatory spread of STAS observed in complementary lobectomy specimens supported reclassifying STAS-positive segmentectomy as R(un). STAS is a critical concern for the surgical completeness evaluation after segmentectomy.

Survival benefit of adjuvant chemotherapy after resection of Stage I lung adenocarcinoma containing micropapillary components

BACKGROUND

The usefulness of postoperative adjuvant chemotherapy (ACT) for patients with stage I lung adenocarcinoma with micropapillary (MIP) components remains unclear. We analyzed whether postoperative ACT could reduce recurrence in patients with stage I lung adenocarcinoma with MIP components, thereby improving their overall survival (OS) and disease-free survival (DFS).

METHODS

Data for patients with pathologically confirmed stage I lung adenocarcinoma with MIP components from January 2012 to December 2018 were retrospectively analyzed. OS and DFS were analyzed in groups and subgroups.

RESULTS

Overall, 259 patients were enrolled. Patients who received ACT in stage IA showed significantly better survival than did those with no-adjuvant chemotherapy (NACT); (5-year OS 89.4% vs. 73.6%, p < 0.001; 5-year DFS 87.2% vs. 66.0%, p = 0.008). A difference was also observed for in-stage IB patients (5-year OS 82.0% vs. 51.8%, p = 0.001; 5-year DFS 76.0% vs. 41.11 %, p = 0.004). In subgroup analysis based on the proportion of MIP components, patients with 1%-5% MIP components had a significantly better prognosis in the ACT group than in the NACT group (5-year OS 82.4% vs. 66.0%, p = 0.005; 5-year DFS 76.5% vs. 49.1%, p = 0.032). A similar difference was observed for patients with MIP ≥5% (5-year OS 80.7% vs. 47.8%, p = 0.009; 5-year DFS 73.11% vs. 43.5%, p = 0.007).

CONCLUSION

Among patients with stage I lung adenocarcinoma with MIP components, those who received ACT showed significant survival benefits compared to those without ACT. Patients with lung adenocarcinoma with MIP components could benefit from ACT when the MIP was ≥1%.

EGFR co-mutation is associated with the risk of recurrence in invasive lung adenocarcinoma with the micropapillary component

BACKGROUND

Invasive lung adenocarcinoma (LUAD) patients with the micropapillary (MPP) component tend to have extremely poor prognosis. To optimize clinical outcomes, a better understanding of specific concurrent gene alterations and their impact on the prognosis of patients with the MPP component is necessary.

METHOD

A total of 621 Chinese patients with surgically resected invasive LUAD who underwent genetic testing for lung cancer were enrolled in this retrospective study. The genomic profiling of major lung cancer-related genes based on next-generation sequencing (NGS) was carried out on formalin-fixed paraffin-embedded tumor samples.

RESULT

Among 621 patients with invasive LUAD, 154 (24.8%, 154/621) had the MPP component. We found that PIK3CA (4.5% vs 1.3%), KRAS (9.1% vs 4.7%), and ROS1 (2.6% vs 0.4%) were more frequent in patients with the MPP component than those without the MPP component (P < 0.05). The co-mutation occurred in 66 patients (10.6%, 66/621), of which 19 patients with the MPP component. Most of them were EGFR co-mutations (89.5%, 17/19), including EGFR and PIK3CA, EGFR and ERBB2, and other types. Patients with the MPP component who harbored EGFR co-mutations showed significantly worse recurrence-free survival (RFS) than single EGFR mutation (median RFS 20.1 vs 30.5 months; hazard ratio [HR]: 8.008; 95% confidence interval [CI]: 1.322-48.508).

CONCLUSIONS

Patients with the MPP component harbored the co-mutation of driver genes had a higher risk of recurrence after surgery, especially in patients with EGFR co-mutation. EGFR co-mutation was a significant prognostic factor for RFS in patients with the MPP component.

Validation of the Proposed International Association for the Study of Lung Cancer Residual Tumor Classification to Upgrade Extracapsular Extension of Tumor in Nodes From R0 to Incomplete Resection

INTRODUCTION

The International Association for the Study of Lung Cancer (IASLC) proposed a revised R classification to upstage extracapsular extension (ECE) of tumor in nodes from R0 to R1. Nevertheless, evidence to confirm this proposal is insufficient.

METHODS

The study included 4061 surgical patients with NSCLC. After reclassification by IASLC-R classification, overall survival (OS) was analyzed to compare patients with ECE with those with R0, R(un), and incomplete resection (R1 and R2). The recurrence pattern of ECE was evaluated to determine whether it correlated with incomplete resection.

RESULTS

Among 1136 patients with N disease, those without ECE (n = 754, 67%) had a significantly better OS than those with ECE (n = 382, 33%) (p < 0.001). This negative prognostic significance was consistent across multiple subgroups. Multivariate analysis revealed that ECE was an independent prognostic risk factor (p < 0.001). When patients with ECE were separated from the IASLC-R1 group, their OS was significantly worse than that of IASLC-R(un) patients, but comparable to that of the remaining patients in the IASLC-R1 patients when analyzing all patients and patients with N disease. Moreover, patients with ECE had an increased risk of local recurrence in the mediastinum (p < 0.001), ipsilateral lung (p = 0.031), and malignant pleural effusion or nodes (p = 0.004) but not distant recurrence including contralateral or both lungs (p = 0.268), liver (p = 0.728), brain (p = 0.252), or bone (p = 0.322).

CONCLUSIONS

The prognosis of ECE patients is comparable with that of R1 patients. Moreover, their higher risk of local recurrence strongly suggests the presence of occult residual tumor cells in the surgical hemithoracic cavity. Therefore, upgrading ECE into incomplete resection is reasonable.

A Multi-institutional Analysis of the Combined Effect of Micropapillary Component and Consolidation-to-Tumor Ratio >0.5 on the Prognosis of Pathological, Stage IA3, Lung Adenocarcinoma

INTRODUCTION

The study investigated the synergistic effect of the micropapillary (MIP) component and consolidation-to-tumor ratio (CTR) on the recurrence and survival of patients with pathologic stage IA3 lung adenocarcinoma.

METHODS

We enrolled 419 patients confirmed pathological stage IA3 adenocarcinoma from four institutions. Kaplan-Meier analysis was performed to examine the value of the MIP component and CTR on relapse-free survival (RFS) and overall survival (OS). The cumulative recurrence between different stages was analyzed by using cumulative event curves.

RESULTS

RFS (P < 0.0001) and OS (P = 0.008) in the presence of the MIP group were significantly lower than those in the absence of the MIP group, and CTR > 5 only reduced RFS (P = 0.0004), but not OS (P = 0.063), in the patients. In addition, the prognosis of patients with both the MIP component and CTR > 5 was worse than that of those without the MIP component or CTR ≤ 5. Therefore, we established new subtypes of the stage IA3: IA3a, IA3b, and IA3c. RFS and OS for IA3c staging were significantly lower than those for IA3a and IA3b. For IA3c, the cumulative incidence of local recurrence (P < 0.001) and that of distant metastasis (P = 0.004) were significantly higher than those for IA3a and IA3b.

CONCLUSIONS

The MIP component combined with CTR > 0.5 can effectively predict the prognosis of patients with pathological stage IA3 lung adenocarcinoma and may offer more detailed recurrence and survival information according to the established subtype stage of IA3.

Stromal micropapillary pattern and CD44s expression predict worse outcome in lung adenocarcinomas with micropapillary pattern

OBJECTIVES

This study aims to investigate the clinicopathologic characteristics of lung adenocarcinoma with micropapillary pattern (MPP) and the expression of CD44s and CD44v6 in MPP.

METHODS

A total of 202 patients diagnosed with primary lung adenocarcinoma with MPP were included. We estimated the proportion of MPP in each tumor tissue and divided MPP into aerogenous micropapillary pattern (AMP) and stromal micropapillary pattern (SMP). The expression of CD44s and CD44v6 was estimated by immunohistochemical staining. Clinicopathologic data were collected from the patients' medical records. We also collected patients' follow-up data and used PFS (progression-free survival) as a survival indicator.

RESULTS

Lung adenocarcinoma with MPP had a high risk of pleural invasion, lymph node metastasis, in advanced TNM stage, and a high rate of EGFR mutation. The presence of SMP indicated a higher rate of pleural invasion, lymphovascular invasion, lymph node metastasis, and a worse PFS compared with pure AMP. We found high expression of CD44s in micropapillary, especially in AMP, while the absence of CD44s expression indicated shorter survival, which was an independent unfavorable factor for PFS.

CONCLUSIONS

Lung adenocarcinoma with micropapillary pattern indicated an unfavorable prognosis, which had two different pattens, AMP and SMP. SMP indicated a worse survival than AMP, and was an independent unfavorable factor for PFS. So, AMP/SMP subclassification is necessary to evaluate patient's prognosis. Furthermore, the absent expression of CD44s in micropapillary indicated shorter survival, especially in patients with EGFR mutation. Herein, CD44s may be a biological marker for micropapillary lung adenocarcinoma.

Single-cell transcriptomics reveals the drivers and therapeutic targets of lymph node metastasis in lung adenocarcinoma

Lymph node metastasis (LNM) is usually the most common metastatic pathway in lung adenocarcinoma (LUAD) and is associated with a poorer prognosis and higher possibility of recurrence. Therefore, discovering the drivers and therapeutic targets of LNM is important for early and non-invasive detection of patients with a high risk of LNM and guiding individualized therapy. Various cell constitutions of the primary tumor and lymph node microenvironment was characterized based on scRNA-seq data. The copy number variation (CNV) analysis was performed to probe clonal structures and origins of metastatic lymph nodes, and found 6q loss and 20q gain may drive LNM in LUAD. Then a LNM-related cell subset, named Scissor+ cells, was identified using the Scissor algorithm. And cell-cell communication network among Scissor+ cells and microenvironment was further analyzed. Besides, a pro-LNM signature was subsequently constructed based on 27 genes using pseudotime trajectory analysis and gene set variation analysis. The pro-LNM signature showed a significant correlation with N stage and a good predictive ability of LUAD survival. At last, we identified that erastin and gefitinib could potentially inhibit LNM by targeting Scissor+ cells based on the drug sensitivity data of the cancer cell lines, which provided new insights for LUAD therapy.

Risk profiles and a concise prediction model for lymph node metastasis in patients with lung adenocarcinoma

BACKGROUND

Lung cancer is the second most commonly diagnosed cancer and ranks the first in mortality. Pathological lymph node status(pN) of lung cancer affects the treatment strategy after surgery while systematic lymph node dissection(SLND) is always unsatisfied.

METHODS

We reviewed the clinicopathological features of 2,696 patients with LUAD and one single lesion ≤ 5 cm who underwent SLND in addition to lung resection at the Sun Yat-Sen University Cancer Center. The relationship between the pN status and all other clinicopathological features was assessed. All participants were stochastically divided into development and validation cohorts; the former was used to establish a logistic regression model based on selected factors from stepwise backward algorithm to predict pN status. C-statistics, accuracy, sensitivity, and specificity were calculated for both cohorts to test the model performance.

RESULTS

Nerve tract infiltration (NTI), visceral pleural infiltration (PI), lymphovascular infiltration (LVI), right upper lobe (RUL), low differentiated component, tumor size, micropapillary component, lepidic component, and micropapillary predominance were included in the final model. Model performance in the development and validation cohorts was as follows: 0.861 (95% CI: 0.842-0.883) and 0.840 (95% CI: 0.804-0.876) for the C-statistics and 0.803 (95% CI: 0.784-0.821) and 0.785 (95% CI: 0.755-0.814) for accuracy, and 0.754 (95% CI: 0.706-0.798) and 0.686 (95% CI: 0.607-0.757) for sensitivity and 0.814 (95% CI: 0.794-0.833) and 0.811 (95% CI: 0.778-0.841) for specificity, respectively.

CONCLUSION

Our study showed an easy and credible tool with good performance in predicting pN in patients with LUAD with a single tumor ≤ 5.0 cm without SLND and it is valuable to adjust the treatment strategy.

Development of the semi-dry dot-blot method for intraoperative detecting micropapillary component in lung adenocarcinoma based on proteomics analysis

BACKGROUND

Micropapillary (MIP) component was a major concern in determining surgical strategy in lung adenocarcinoma (LUAD). We sought to develop a novel method for detecting MIP component during surgery.

METHODS

Differentially expressed proteins between MIP-positive and MIP-negative LUAD were identified through proteomics analysis. The semi-dry dot-blot (SDB) method which visualises the targeted protein was developed to detect MIP component.

RESULTS

Cellular retinoic acid-binding protein 2 (CRABP2) was significantly upregulated in MIP-positive LUAD (P < 0.001), and the high CRABP2 expression zone showed spatial consistency with MIP component. CRABP2 expression was also associated with decreased recurrence-free survival (P < 0.001). In the prospective cohort, the accuracy and sensitivity of detecting MIP component using SDB method by visualising CRABP2 were 82.2% and 72.7%, which were comparable to these of pathologist. Pathologist with the aid of SDB method would improve greatly in diagnostic accuracy (86.4%) and sensitivity (78.2%). In patients with minor MIP component (≤5%), the sensitivity of SDB method (63.6%) was significantly higher than pathologist (45.4%).

CONCLUSIONS

Intraoperative examination of CRABP2 using SDB method to detect MIP component reached comparable performance to pathologist, and SDB method had notable superiority than pathologist in detecting minor MIP component.

Micropapillary and Solid Histologic Patterns in N1 and N2 Lymph Node Metastases Are Independent Factors of Poor Prognosis in Patients With Stages II to III Lung Adenocarcinoma

INTRODUCTION

High-grade histologic patterns are associated with poor prognosis in patients with primary nonmucinous lung adenocarcinoma (ADC). We investigated whether the presence of micropapillary (MIP), solid (SOL), or both patterns in lymph node (LN) metastases has prognostic value.

METHODS

Patients who underwent lobectomy for pathologic stages II to III lung ADC with N1 or N2 LN metastases (N = 360; 2000-2012) were analyzed. We assessed overall survival (OS), lung cancer-specific cumulative incidence of death (LC-CID), and cumulative incidence of recurrence (CIR) between patients with and without MIP/SOL patterns in LN metastases. Multivariable Cox regression analysis was used to quantify the association between MIP/SOL patterns and outcomes.

RESULTS

MIP and SOL in LN metastases were associated with a higher incidence of smoking history (p = 0.004), tumor necrosis (p = 0.013), and spread of tumor through air spaces (p < 0.0001), a higher prevalence of MIP or SOL in the primary tumor (p < 0.0001), shorter OS (5-y OS, 40% [95% confidence interval or CI: 29%-56%] versus 63% [48%-83%] for no MIP/SOL in LNs, p = 0.03), higher LC-CID (5-y, 43% [29%-56%] versus 14% [4%-29%], p = 0.013), and higher CIR (5-y, 65% [50%-77%] versus 43% [25%-60%], p = 0.057). MIP and SOL in LN metastases were independently associated with poor outcomes: OS (hazard ratio [HR] = 1.81 [95% CI: 1.00-3.29], p = 0.05), LC-CID (HR = 3.10 [1.30-7.37], p = 0.01), and CIR (HR = 2.06 [1.09-3.90], p = 0.026).

CONCLUSIONS

MIP/SOL histologic patterns in N1 or N2 LN metastases are associated with worse outcomes in patients with stages II to III lung ADC. MIP/SOL histologic patterns in LN metastases can stratify patients with high-risk stages II to III lung ADC.

Association of frequent hypermethylation with high grade histological subtype in lung adenocarcinoma

Lung adenocarcinoma is classified morphologically into five histological subtypes according to the WHO classification. While each histological subtype correlates with a distinct prognosis, the molecular basis has not been fully elucidated. Here we conducted DNA methylation analysis of 30 lung adenocarcinoma cases annotated with the predominant histological subtypes and three normal lung cases using the Infinium BeadChip. Unsupervised hierarchical clustering analysis revealed three subgroups with different methylation levels: high-, intermediate-, and low-methylation epigenotypes (HME, IME, and LME). Micropapillary pattern (MPP)-predominant cases and those with MPP components were significantly enriched in HME (p = 0.02 and p = 0.03, respectively). HME cases showed a significantly poor prognosis for recurrence-free survival (p < 0.001) and overall survival (p = 0.006). We identified 365 HME marker genes specifically hypermethylated in HME cases with enrichment of "cell morphogenesis" related genes; 305 IME marker genes hypermethylated in HME and IME, but not in LME, with enrichment "embryonic organ morphogenesis"-related genes; 257 Common marker genes hypermethylated commonly in all cancer cases, with enrichment of "regionalization"-related genes. We extracted surrogate markers for each epigenotype and designed pyrosequencing primers for five HME markers (TCERG1L, CXCL12, FAM181B, HOXA11, GAD2), three IME markers (TBX18, ZNF154, NWD2) and three Common markers (SCT, GJD2, BARHL2). DNA methylation profiling using Infinium data was validated by pyrosequencing, and HME cases defined by pyrosequencing results also showed the worse recurrence-free survival. In conclusion, lung adenocarcinomas are stratified into subtypes with distinct DNA methylation levels, and the high-methylation subtype correlated with MPP-predominant cases and those with MPP components and showed a poor prognosis.

Frozen sections accurately predict the IASLC proposed grading system and prognosis in patients with invasive lung adenocarcinomas

INTRODUCTION

The International Association for the Study of Lung Cancer (IASLC) newly proposed grading system for lung adenocarcinomas (ADC) has been shown to be of prognostic significance. Hence, intraoperative consultation for the grading system was important regarding the surgical decision-making. Here, we evaluated the accuracy and interobserver agreement for IASLC grading system on frozen section (FS), and further investigated the prognostic performance.

METHODS

FS and final pathology (FP) slides were reviewed by three pathologists for tumor grading in 373 stage I lung ADC following surgical resection from January to June 2013 (retrospective cohort). A prospective multicenter cohort (January to June 2021, n = 212) were included to confirm the results.

RESULTS

The overall concordance rates between FS and FP were 79.1% (κ = 0.650) and 89.6% (κ = 0.729) with substantial agreement in retrospective and prospective cohorts, respectively. Presence of complex gland was the only independent predictor of discrepancy between FS and FP (presence versus. absence: odds ratio, 2.193; P = 0.015). The interobserver agreement for IASLC grading system on FS among three pathologists were satisfactory (κ = 0.672 for retrospective cohort; κ = 0.752 for prospective cohort). Moreover, the IASLC grading system by FS diagnosis could well predict recurrence-free survival and overall survival for patients with stage I invasive lung ADC.

CONCLUSIONS

Our results suggest that FS had high diagnostic accuracy and satisfactory interobserver agreement for IASLC grading system. Future prospective studies are merited to validate the feasibility of using FS to match patients into appropriate surgical type.

The IASLC Proposed Grading System Accurately Predicts Prognosis and Mediastinal Nodal Metastasis in Patients With Clinical Stage I Lung Adenocarcinoma

The International Association for the Study of Lung Cancer (IASLC) recently proposed a new grading system for lung adenocarcinoma (LUAD). We aimed to validate the prognostic performance of the grading system and explore its role in guiding the strategy of lymph node (LN) dissection. We retrospectively reviewed 1029 patients with clinical stage I LUAD who underwent surgery between 2011 and 2013. The association between mediastinal nodal metastasis and grading system was evaluated. To investigate the value of the grading system in guiding LN dissection strategies, 3 pathologists evaluated the feasibility of identifying the grading system using frozen section (FS). The differences in prognosis between all neighboring grades were highly significant based on the grading system ( P <0.001). Notably, almost no grade 1 LUAD (1.4%) had pN2 disease, whereas higher rates were found in grade 2 LUAD (9.6%) and grade 3 LUAD (18.3%) ( P <0.001). Multivariate logistic regression analysis revealed that higher tumor grade was an independent predictor of mediastinal nodal metastasis ( P =0.002). Moreover, limited mediastinal LN dissection had equivalent prognosis in grade 1 LUAD, but significantly worse prognosis in grade 2 and grade 3 LUAD than systematic mediastinal LN dissection. The overall accuracy of using intraoperative FS to identify the IASLC grading system was 85.4% (κ=0.765) with substantial agreement. The IASLC grading system could accurately stratify prognosis and predict mediastinal nodal metastasis in patients with clinical stage I LUAD. FS was feasible for identifying the IASLC grading system.

Lymph node micrometastasis in non-small cell lung cancer

Lung cancer has some of the highest morbidity and mortality rates of all cancers, and an important risk factor for mortality in patients with lung cancer is tumor metastasis. Even if a tumor is completely removed at an early stage of the disease, quite a number of patients still have the risk of recurrence. With the advent of molecular diagnostic and therapeutics, more and more studies have found that a poor prognosis may be related to lymph node micrometastasis. However, clinicians still find that predicting the prognosis and choosing the type of surgery and postoperative adjuvant chemotherapy are still challenging. Thus, this article reviews the current research status of lymph node micrometastasis in non-small cell lung cancer, envision to provide some updates and insights in this area.

CEA-Ki-67- Pathologic Subtype: An Adjunct Factor for Refining Prognosis in Stage I Pulmonary Adenocarcinoma

Objectives

The prognosis for stage I pulmonary adenocarcinoma is generally good. However, some patients with stage I pulmonary adenocarcinoma have an unexpectedly poor outcome. This warrants consideration of adjunct markers. In this study, we analyze carcinoembryonic antigen, Ki-67, and a pathologic subtype in combination for prognostic evaluation of stage I pulmonary adenocarcinoma. These factors were selected for study as they have been shown to be individually associated with prognosis in many studies.

Methods

A total of 650 patients with stage I pulmonary adenocarcinoma were investigated retrospectively. Each patient was re-staged using standard TNM criteria. Carcinoembryonic antigen (CEA) values were obtained from preoperative blood samples, and Ki-67 was evaluated with tumor tissue immunohistochemistry. Patient clinicopathologic characteristics, survival status, and date of death were obtained from medical records and telephone follow-up.

Results

CEA > 4.4 ng/ml, Ki-67 > 13%, and a solid-micropapillary tumor growth pattern were each independent adverse prognostic markers for 5-year disease specific survival in stage I pulmonary adenocarcinoma. However, in combination, these 3 factors yielded a prognostic value (designated “CEA-Ki-67-pathologic subtype” value). Stage I pulmonary adenocarcinoma of low-risk CEA-Ki-67-pathologic subtype (CKP) value show biologic behavior similar to TNM stage IA1 tumors, while stage I tumors of high-risk CKP value are similar in prognosis to TNM stage II.

Conclusion

The CKP value may be used as an adjunct to the TNM classification, which may yield a more accurately defined prognosis for cases of stage I pulmonary adenocarcinoma. CKP value may identify patients at higher risk who may benefit from adjuvant chemotherapy. Conversely, lower risk CKP values may support avoidance of chemotherapy.

Cost-Sensitive Uncertainty Hypergraph Learning for Identification of Lymph Node Involvement With CT Imaging

Lung adenocarcinoma (LUAD) is the most common type of lung cancer. Accurate identification of lymph node (LN) involvement in patients with LUAD is crucial for prognosis and making decisions of the treatment strategy. CT imaging has been used as a tool to identify lymph node involvement. To tackle the shortage of high-quality data and improve the sensitivity of diagnosis, we propose a Cost-Sensitive Uncertainty Hypergraph Learning (CSUHL) model to identify the lymph node based on the CT images. We design a step named "Multi-Uncertainty Measurement" to measure the epistemic and the aleatoric uncertainty, respectively. Given the two types of attentional uncertainty weights, we further propose a cost-sensitive hypergraph learning to boost the sensitivity of diagnosing, targeting task-driven optimization of the clinical scenarios. Extensive qualitative and quantitative experiments on the real clinical dataset demonstrate our method is capable of accurately identifying the lymph node and outperforming state-of-the-art methods across the board.

[Pathological and Molecular Features of Lung Micropapillary Adenocarcinoma]

肺微乳头腺癌作为高级别肺腺癌，具频发转移、淋巴结浸润、复发率高和总体生存率低的临床特征。该亚型肿瘤中存在特征致癌因子通路的激活和肿瘤免疫微环境的建立。本文拟对近年来微乳头腺癌的病理学表现及分子学特征研究进展作一综述，旨在加深对微乳头型病变的认识，进而为制定特异性治疗策略奠定基础。

Recognition of filigree pattern expands the concept of micropapillary subtype in patients with surgically resected lung adenocarcinoma

Our study aimed to validate the clinicopathological characteristics and prognosis of lung adenocarcinoma (ADC) with a filigree pattern and to further investigate the relationship between the filigree pattern and the classical micropapillary (MP) pattern. We retrospectively reviewed the clinical and pathologic characteristics of 461 Chinese patients with completely resected ADC (stage I, 310; stage II, 44; stage III, 107). The filigree pattern was more likely to be observed in ADC with a higher stage (p = 0.003) and the classical MP pattern (p < 0.001). Patients with filigree-predominant ADC showed poor survival, similar to those with classical MP-predominant ADC. Multivariate analysis confirmed that the presence of the filigree pattern was an independent prognostic factor for recurrence-free survival (hazard ratio (HR), 2.01; 95% confidence interval (CI), 1.50-2.68; p < 0.001) and overall survival (OS; HR, 1.83; 95% CI, 1.34-2.50; p < 0.001). Patients with both classical MP-positive and filigree-positive ADC had the worst survival compared with those with the filigree pattern or classical MP pattern alone. In stage I, ADC with both the filigree and classical MP patterns had a higher incidence of micrometastasis than ADC with the filigree pattern or classical MP pattern alone. Lymph node micrometastasis indicated poor survival in patients with ADC with the filigree pattern or classical MP pattern. Similar clinicopathologic features between patients with the filigree pattern and the classical MP pattern support the inclusion of the filigree pattern in the MP category. Recognition of the filigree pattern could provide helpful prognostic information, especially for stage I ADC.

Targeted Sequencing Analysis of Predominant Histological Subtypes in Resected Stage I Invasive Lung Adenocarcinoma

Objective: Lung adenocarcinoma (LADC) is classified into five main histological subtypes with distinct clinicopathologic characteristics: lepidic-predominant adenocarcinoma (LPA), acinar-predominant adenocarcinoma (APA), papillary-predominant adenocarcinoma (PPA), micropapillary-predominant adenocarcinoma (MPA) and solid-predominant adenocarcinoma (SPA). However, the mutational profiles of predominant histological subtypes have not been well defined. In this study, we aimed to reveal the genomic landscape of 5 main histological subtypes. Patients and Methods: We performed next-generation sequencing (NGS) in a cohort of 86 stage I invasive adenocarcinoma (IAC) patients, using a customized panel including 168 cancer-associated genes. Results: Our analysis identified a total of 302 genomic alterations. Five subtypes showed different mutation profiles with LPA, APA, PPA, MPA and SPA had an average mutation rate of 1.95 (range: 0-5), 2.56 (range: 1-6), 3.5 (range: 1-7), 3.75 (range: 1-8) and 6.05 (range: 2-12), respectively (p=4.17e-06). Driver mutations occurred in 96.55% (83/86) of all patients. EGFR (73.3%), KRAS (9.3%), ALK (4.7%) and MET (4.7%) are the most commonly mutated lung cancer driver genes, TP53 is the top mutated tumor suppressor gene. SPA patients harbored more driver mutations and higher frequency of TP53 than LPA patients. Interestingly, LRP1B mutations, which has been reported to be associated with high tumor mutation burden and better response to immunotherapy, were only detected from 5 SPA patients (p=0.001). No patients from other four cohorts harbored LRP1B mutations. Conclusions: We revealed distinctive mutation landscape of the 5 major histological subtypes of LADC, evident by distinctive average mutation rate with SPA and LPA having the highest and lowest average mutation rate, respectively. SPA patients showed higher mutation rate of LRP1B and higher rates for PD-L1 positivity, indicating that SPA patients may have better response to immunotherapy.

Choice of Treatment for Patients With Non-small-cell Lung Cancer >5 cm Between Surgery Alone and Surgery Plus Adjuvant Radiotherapy

Background: According to the lung cancer staging project, T2b (>5–7 cm) and T3 (>7 cm) non-small cell lung cancers (NSCLC) should be reclassified into T3 and T4 groups. The objective of this study was to evaluate the effect of surgery alone or surgery plus adjuvant radiation (SART) on survival of node-negative patients with NSCLC >5 cm.

Methods: We identified 4557 N0 patients with NSCLC >5 cm in the Surveillance, Epidemiology, and End Results database from 2004 to 2014. Overall survival (OS) and cancer–specific survival (CSS) were compared among patients who underwent surgery alone and SART. The proportional hazards model was applied to evaluate multiple prognostic factors.

Results: 1,042 and 525 patients who underwent surgery alone and SART, respectively were enrolled after propensity-score matching. OS and CSS favored surgery alone rather than SART. Multivariate analysis showed that the number of lymph nodes examined more than six was associated with better OS and CSS for NSCLC >5 cm, especially in patients treated with surgery alone. Lobectomy should be recommended as the primary option for NSCLC >5 to 7 cm, whereas its superiority was not significant over sublobectomy for NSCLC >7 cm.

Conclusion: Surgery alone should be recommended as the first choice for patients with NSCLC >5 cm. The number of examined lymph nodes should be more than six in patients with NSCLC >5 cm, especially for those who undergo surgery alone. For patients with NSCLC >7 cm who could not tolerate lobectomy, sublobectomy might be an alternative surgical procedure.

miR-224, miR-147b and miR-31 associated with lymph node metastasis and prognosis for lung adenocarcinoma by regulating PRPF4B, WDR82 or NR3C2

Background

The present study is to screen lymph node metastasis-related microRNAs (miRNAs) in lung adenocarcinoma (LUAD) and uncover their underlying mechanisms.

Methods

The miRNA microarray dataset was collected from the Gene Expression Omnibus database under accession number GSE64859. The differentially expressed miRNAs (DEMs) were identified using a t-test. Target genes of DEMs were predicted through the miRWalk2.0 database. The function of these target genes was annotated with the clusterProfiler and the Database for Annotation, Visualization and Integrated Discovery (DAVID) tools. Protein-protein interaction network was established using the STRING database to extract hub target genes. The expressions and associations with survival and lymph node metastasis of miRNAs and target genes were validated by analysis of The Cancer Genome Atlas (TCGA) dataset.

Results

Eight DEMs were identified between lymph node metastasis and non-metastasis samples of GSE64859 dataset. miRNA-target gene pairs were predicted between six DEMs and 251 target genes (i.e. hsa-miR-224-PRPF4B, hsa-miR-147b-WDR82 and hsa-miR-31-NR3C2). The clusterProfiler analysis showed WDR82 was involved in the mRNA surveillance pathway, while the GO enrichment analysis using the DAVID database indicated PRPF4B participated in the protein phosphorylation and NR3C2 was related with the transcription, DNA-templated. WDR82 and PRPF4B may be hub genes because they could interact with others. Two DEMs (miR-31-5p and miR-31-3p) and 45 target genes (including PRPF4B and NR3C2) were significantly associated with overall survival. The expressions of miR-224 and miR-147b were validated to be upregulated, while WDR82, PRPF4B and NR3C2 were downregulated in lymph node metastasis samples of TCGA datasets compared with non-metastasis samples. Also, there were significantly negative expression correlations between miR-147b and WDR82, between miR-224 and PRPF4B, as well as between miR-31 and NR3C2 in LUAD samples.

Conclusions

The present study identified several crucial miRNA-mRNA interaction pairs, which may provide novel explanations for the lymph node metastasis and poor prognosis for LUAD patients.

Prognostic impact of micropapillary component in patients with node-negative subcentimeter lung adenocarcinoma: A Chinese cohort study

Background

In this study, we investigated the prognostic significance of a micropapillary (MP) component in patients with subcentimeter lung adenocarcinoma.

Methods

A total of 311 patients with subcentimeter lung adenocarcinoma who underwent surgical resection between January 2009 to December 2012 from seven medical centers were included. Recurrence‐free survival (RFS) and overall survival (OS) were analyzed.

Results

The five‐year RFS was 79.8% in 97 (97/311, 31%) cases of adenocarcinoma with a MP component and 93.5% in the 214 (214/311, 69%) cases without. In multivariate analysis, MP was an independent risk factor for worse RFS (hazard ratio [HR], 3.73; 95% confidence interval [CI]: 1.87–7.42; P < 0.001) and OS (HR, 5.84; 95% CI: 2.20–15.49; P < 0.001). There was no significant difference among wedge resection, segmentectomy and lobectomy on RFS (P = 0.256) and OS (P = 0.103) in patients without MP. Regarding patients with a MP component, lobectomy achieved equivalent prognosis than segmentectomy, and both were better than wedge resection (P = 0.001).

Conclusions

A MP component still suggest a poor prognosis in subcentimeter lung adenocarcinoma. Patients with subcentimeter lung adenocarcinoma with a MP component of 5% or greater treated with wedge resection were at higher risk of recurrence than patients treated with anatomical resection.

Characterization of Extracapsular Lymph Node Involvement and Its Clinicopathological Characteristics in Stage II-IIIA Lung Adenocarcinoma

BACKGROUND

The prognostic impact and clinicopathological characteristics of extracapsular lymph node involvement (ECLNI) in patients with surgically resected lung adenocarcinoma (LUAD) remain unknown in the context of the eighth edition N classification.

PATIENTS AND METHODS

We retrospectively reviewed 279 patients with stage II-IIIA LUAD who underwent lobectomy and lymphadenectomy. The correlations of ECLNI presence and clinicopathological profiles were analyzed. We also assessed the impact of ECLNI on the postoperative survival of pN1 and pN2 LUAD patients.

RESULTS

ECLNI-positive status was more common in patients with high lymph node yield and in patients with multiple stations involved. The logistic regression model identified tumor spread through air spaces, micropapillary component, cribriform component, and nodal stage as predictive factors for ECLNI presence. LUAD patients with ECLNI presence had an increased risk of locoregional recurrence compared with those without (p < 0.001). Presence of ECLNI was confirmed as an independent risk factor for worse recurrence-free survival (RFS) (p < 0.001) and overall survival (OS) (p < 0.001) in the entire cohort. Among the 61 patients with ECLNI(+)pN2 disease, our analysis revealed that adjuvant radiation was a significant predictor of improved RFS and OS. In addition, ECLNI status provides additional precision in stratifying pN1 and pN2 patients with significantly different RFS and OS.

CONCLUSIONS

Our data suggest that ECLNI remains a strong prognosticator of unfavorable OS and RFS for LUADs in the context of the eighth edition N classification. Adjuvant radiation should be actively considered for pN1b and pN2 LUAD patients with ECLNI presence.

Impact of histological components on selecting limited lymphadenectomy for lung adenocarcinoma ≤ 2 cm

OBJECTIVES

There is still some dispute regarding the performance of limited mediastinal lymphadenectomy (LML) even for lung adenocarcinoma ≤ 2 cm. We aimed to recognize the potential candidates who can benefit from LML based on the percentage of histological components (PHC).

METHODS

We analyzed 1160 surgical patients with invasive lung adenocarcinoma ≤ 2 cm from seven institutions between January 2012 and December 2015. All histological subtypes were listed in 5% increments by pathological slices. To test the accuracy of frozen section in judging PHC, frozen section slides from 140 cases were reviewed by three pathologists.

RESULTS

There were 882 patients with systematic mediastinal lymphadenectomy (SML) and 278 with LML. Multivariable analysis indicated that, the total percentage of micropapillary and solid components (PHC_MIP+S) > 5 % was the independent predictor of N2 metastasis (P < 0.001). Overall, recurrence-free survival (RFS) and overall survival (OS) favored SML compared with LML, but the subgroup analysis revealed LML and SML had similar prognosis in the group of PHC_MIP+S ≤ 5 %. Moreover, multivariable Cox analysis showed LML (vs. SML) was independently associated with worse prognosis for patients with PHC_MIP+S > 5 % (RFS, HR = 2.143, P < 0.001; OS, HR=1.963, P < 0.001), but not for those with PHC_MIP+S ≤ 5 % (RFS, P = 0.398; OS, P = 0.298). The sensitivity and specificity of frozen section to intraoperatively identify PHC_MIP+S ≤ 5 % were 97.6 % and 84.2 %, respectively.

CONCLUSIONS

PHC_MIP+S showed the predictive value for N2 metastasis and procedure-specific outcome (LML vs. SML). It may serve as a feasible indicator for identifying proper candidates of LML by using intraoperative frozen section.

Time trend of mediastinal lymph node dissection in stage IA non-small cell lung cancer patient who undergo lobectomy: a retrospective study of surveillance, epidemiology, and end results (SEER) database

Background

Although lobectomy with mediastinal lymph node dissection (MLND) is the first option for early-stage non-small cell lung cancer (NSCLC) patients, the time trends of MLND in stage IA NSCLC patients who undergo a lobectomy are not clear still.

Methods

We included stage IA NSCLC patients who underwent lobectomy or lobectomy with MLND between 2003 and 2013 in the SEER database. The time trend of MLND was compared among patients who underwent a lobectomy.

Results

For stage T1a patients, the lobectomy group and lobectomy with MLND group had no differences in postoperative overall survival (OS) (P = 0.34) or lung-cancer specific survival (LCSS) (P = 0.18) between 2003 and 2013. For stage T1b patients, the OS (P = 0.01) and LCSS (P = 0.01) were different between the lobectomy group and the lobectomy with MLND group in the period from 2003 to 2009; however, only OS (P = 0.04), not LCSS (P = 0.14), was different between the lobectomy group and the lobectomy with MLND group between 2009 and 2013. For T1c patients, the OS (P = 0.01) and LCSS (P = 0.02) were different between the two groups between 2003 and 2009 but not between 2009 and 2013 (P = 0.60; P = 0.39). From the Cox regression analysis, we found that the factors affecting OS/LCSS in T1b and T1c patients were age, sex, year of diagnosis, histology, and grade, in which year of diagnosis was the obvious factor (HR = 0.79, CI = 0.71–0.87; HR = 0.73, CI = 0.64–0.84).

Conclusions

There was a time trend in prognosis differences between the lobectomy group and lobectomy with MLND group for T1b and T1c stage NSCLC patients.

A comprehensive study on the oncogenic mutation and molecular pathology in Chinese lung adenocarcinoma patients

BACKGROUND

Several genetic driver alterations have been identified in micropapillary lung adenocarcinoma (MPA). However, the frequency of co-alteration of ROS1, EGFR, and EML4-ALK is yet unclear. Herein, we investigated the relationship between clinicopathologic characteristics and well-identified driver mutations of MPA compared with non-micropapillary lung adenocarcinoma (LA).

METHODS

Formalin-fixed paraffin-embedded (FFPE) sections derived from lung adenocarcinoma patients who never received adjuvant chemotherapy or radiation therapy prior to surgical resection were collected from October 2016 to June 2019. EGFR mutations, ROS1 rearrangements, and EML4-ALK fusion were identified in a set of 131 MPA and LA cases by using the amplification refractory mutation system (ARMS). The response rate and duration of response were assessed using Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1).

RESULTS

EGFR mutations had occurred in 42 (76.4%) MPA patients and 42 (55.3%) LA patients. Interestingly, ROS1 rearrangements were highly enriched only in the MPA cases (6/55, 10.9%) but rarely in the LA cases (1/76, 1.3%). Furthermore, 7.3% (4/55) MPA samples had double gene mutations, while only 1.3% (1/76) LA cases had double gene alterations. Of 5 patients with harboring two driver oncogene mutations, four patients (80%) obtained partial response, and one patient (20%) suffered recurrence.

CONCLUSIONS

A higher prevalence of ROS1 rearrangement or combined mutations of ROS1, EGFR, and EML4-ALK may play a critical role in the tumorigenesis of MPA. These findings provide a novel therapeutic strategy for patients with malignant MPA through combining TKIs than one TKI.

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

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

Both the presence of a micropapillary component and the micropapillary predominant subtype predict poor prognosis after lung adenocarcinoma resection: a meta-analysis

Objective

It has been confirmed that the micropapillary (MP) pattern is a poor prognostic factor after resection of lung adenocarcinoma (ADC), but the proportion of the MP component as a prognostic criterion is still controversial. Hence, a meta-analysis was performed to evaluate whether the presence of an MP component has equal prognostic power as the MP predominant subtype.

Methods

Literature retrieval was performed in the MEDLINE, EMBASE, and Cochrane databases until December 23, 2019. Eligible studies were selected based on the inclusion and exclusion criteria. The included studies were divided into two subgroups, the MP component subgroup and the MP predominant subgroup, according to the proportion of the MP pattern to analyse the effect of this pattern on disease-free survival (DFS) and overall survival (OS). The hazard ratio (HR) and 95% confidence interval (CI) were extracted from each study. Review Manager 5.3 was used for statistical analyses.

Results

Finally, 10 studies, including a total of 4934 lung ADC patients, were included in this meta-analysis. Our results indicated a significantly worse pooled DFS (HR 1.62, 95% CI 1.20–2.21) and OS (HR 1.53, 95% CI 1.19–1.96) in the subgroup of MP predominant subtype patients. The pooled DFS (HR 1.80, 95% CI 1.45–2.85) and OS (HR 2.26, 95% CI 1.46–3.52) were also poor in the subgroup of patients with the presence of an MP component.

Conclusions

Both the presence of an MP component and the MP predominant subtype are related to poor DFS and OS after lung ADC resection and represent adverse prognostic factor for lung ADC patients. However, there are some limitations in this meta-analysis, and quantitative stratification based on the proportion of the MP component is needed to explore its effect on prognosis of lung ADC patients in the future.

Minimizing residual occult nodal metastasis in NSCLC: recent advances, current status and controversies

Introduction: Nodal involvement in lung cancer is a significant determinant of prognosis and treatment management. New evidence exists regarding the management of occult lymph node metastasis and residual disease in the fields of imaging, mediastinal staging, and operative management.Areas covered: This review summarizes the latest body of knowledge on the identification and management of occult lymph node metastasis in NSCLC. We focus on tumor-specific characteristics; imaging modalities; invasive mediastinal staging; and operative management including, technique, degree of resection, and lymph node examination.Expert opinion: Newly identified risk-factors associated with nodal metastasis including tumor histology, location, radiologic features, and metabolic activity are not included in professional societal guidelines due to the heterogeneity of their reporting and uncertainty on how to adopt them into practice. Imaging as a sole diagnostic method is limited. We recommend confirmation with invasive mediastinal staging. EBUS-FNA is the best initial method, but adoption has not been uniform. The diagnostic algorithm is less certain for re-staging of mediastinal nodes after neoadjuvant therapy. Mediastinal node sampling during lobectomy remains the gold-standard, but evidence supports the use of minimally invasive techniques. More study is warranted regarding sublobar resection. No consensus exists regarding lymph node examination, but new evidence supports reexamination of current quality metrics.

[Advances in Lymph Node Metastasis and Lymph Node Dissection in Early Non-small Cell Lung Cancer]

肺癌是目前我国发病率和死亡率均居首位的恶性肿瘤，其中以非小细胞肺癌为主要病理类型。淋巴结转移是非小细胞肺癌最常见和最主要的转移途径，也是影响肺癌分期和预后最重要的因素。由于目前通过现有手段术前很难准确判断早期非小细胞肺癌患者的淋巴结受累情况。因此，在早期非小细胞肺癌中，尤其是在临床Ⅰ期非小细胞肺癌患者中，淋巴结清扫方式一直存在很大争议。本文就非小细胞肺癌淋巴结转移的规律及清扫方式进行综述。

The Association Between Lymph Node Stage and Clinical Prognosis in Thyroid Cancer

Purpose: To investigate the association between lymph node (N) stage and clinical outcome in thyroid cancer patients with initial distant metastasis. Methods: A total of 3,198 cases (1,435 males and 1,763 females) between 2004 and 2015 with initial distant metastasis were obtained from the surveillance, epidemiology, and end results (SEER) database. Patients with a median follow up time of 13 months and a median age of 66 years were analyzed. A total of 1,407 cases had detailed information regarding the four most common metastatic organs after the year 2010. Kaplan-Meier (KM) analyses, log-rank tests, Cox regression, and logistic regression analyses were used. Results: Among the whole cohort, 33.4% (1,069/3,198), 14.5% (464/3,198), 10.1% (322/3,198), 34.2% (1,094/3,198), and 7.8% (249/3,198) of the patients were at the stage of N0, NX, N1a, N1b, and N1NOS (referring to metastasis to regional lymph nodes but not otherwise specified), respectively. The KM curves demonstrated that the patients at the NX stage had the worst survival. The NX and N1b groups had the highest hazard ratios (HRs) of 1.83 (95%CI 1.46-2.31) and 1.78 (95%CI 1.52-2.10) after adjusting age, race, gender, and tumor size (p < 0.001) compared with N0 group. The lung was the most common metastatic site, with a rate of 51.2% (720/1,407). Compared with the N0 group, N1 patients had higher odds (OR 1.63, 95%CI 1.31-2.01, p < 0.001) for lung metastasis. Similar results were obtained in papillary thyroid cancer (PTC) sub-cohort. Conclusions: Overall, the TC patients at the NX stage had the highest mortality risk, followed by N1b, N1a, and N0 groups. Compared with N0 patients, N1 patients were more likely to have lung metastasis. The poor prognosis for TC patients with the NX stage may make more aggressive treatment reasonable.

Glucose Metabolic Reprogramming and Cell Proliferation Arrest in Colorectal Micropapillary Carcinoma

Background

Micropapillary carcinoma (MPC) has been reported as an aggressive variant of colorectal carcinoma (CRC) associated with frequent lymphovascular invasion and poor outcome. Altered glycogen metabolism by metabolic reprogramming plays a critical role for cancer cell growth and survival. We aimed to investigate glucose metabolic reprogramming in colorectal MPC.

Methods

Immmunostains for Ki-67 and glucose transporter 1 (GLUT1) were performed on 10 colorectal MPCs. Real-time PCR analysis of expressions of GLUT1 and glycogen metabolizing enzymes: glycogen synthase (GYS1) and glycogen phosphorylase (PYGL) was performed on cultured monolayer and three-dimensional (3D) spheroid HCT116 colon cancer cells.

Results

GLUT1 was strongly expressed in MPC as compared to adjacent conventional glandular component, and was also significantly increased expression in 3D spheroids. Upregulation of GYS1 and PYGL was markedly increased in 3D spheroids. The proliferation rate (Ki-67) of MPC was significantly lower compared to conventional glandular component. The 3D spheroids showed increased cell cycle arrest. Our results demonstrate altered glycogen metabolism in colorectal MPC.

Conclusion

The reprogramming of glycogen metabolism in MPC provides a source of energy contributing to tumor cell survival in a low proliferation state. Targeting glucose-regulated metabolism may warrant consideration as possible MPC therapies.

Micropapillary adenocarcinoma of lung: Morphological criteria and diagnostic reproducibility among pulmonary pathologists

CONTEXT

Invasive micropapillary adenocarcinoma (MPC) is an aggressive variant of lung adenocarcinoma, frequently manifesting with advanced stage lymph node metastasis and decreased survival.

OBJECTIVE

Identification of this morphology is important, as it is strongly correlated with poor prognosis regardless of the amount of MPC component. To date, no study has investigated the morphological criteria used to objectively diagnose it.

DESIGN

Herein, we selected 30 cases of potential MPC of lung, and distributed 2 digital images per case among 15 pulmonary pathology experts. Reviewers were requested to diagnostically interpret, assign the percentage of MPC component, and record the morphological features they identified. The noted features included: columnar cells, elongated slender cell nests, extensive stromal retraction, lumen formation with internal epithelial tufting, epithelial signet ring-like forms, intracytoplasmic vacuolization, multiple nests in the same alveolar space, back-to-back lacunar spaces, epithelial nest anastomosis, marked pleomorphism, peripherally oriented nuclei, randomly distributed nuclei, small/medium/large tumor nest size, fibrovascular cores, and spread through air-spaces (STAS).

RESULTS

Cluster analysis revealed three subgroups with the following diagnoses: "MPC", "combined papillary and MPC", and "others". The subgroups correlated with the reported median percentage of MPC. Intracytoplasmic vacuolization, epithelial nest anastomosis/confluence, multiple nests in the same alveolar space, and small/medium tumor nest size were the most common criteria identified in the cases diagnosed as MPC. Peripherally oriented nuclei and epithelial signet ring-like forms were frequently identified in both the "MPC" and "combined papillary and MPC" groups.

CONCLUSIONS

Our study provides objective diagnostic criteria to diagnose MPC of lung.

Novel approach for predicting occult lymph node metastasis in peripheral clinical stage I lung adenocarcinoma

Background

Occult nodal metastasis results in a poor prognosis for lung cancer patients. The aim of this study was to develop an efficient approach for predicting occult nodal metastasis in peripheral clinical stage I lung adenocarcinoma.

Methods

Data for 237 peripheral clinical stage I lung adenocarcinoma patients who underwent complete resection were retrospectively reviewed. Univariate and multivariate analyses were performed to investigate predictors of occult nodal metastasis. Kaplan-Meier analysis was performed for survival.

Results

Occult nodal metastasis was detected in 26/237 (11.0%) patients. Nodule type, tumor SUVmax, whole tumor size, solid tumor size, and preoperative serum carcinoembryonic antigen (CEA) were identified as preoperative predictors of occult nodal metastasis (all P<0.05). Solid tumor size (P<0.001) and preoperative serum CEA (P=0.004) were identified as independent predictors on multivariate analysis. A prediction model was established using the independent predictors. The occult nodal metastasis rate was 2.4% with solid tumor size ≤2.3 cm (low-risk group), 17.0% with solid tumor size >2.3 cm and CEA ≤5 ng/mL (moderate-risk group), and 56.0% with solid tumor size >2.3 cm and CEA >5 ng/mL (high-risk group). The occult nodal metastasis rate was significantly higher in papillary-predominant (11.0%) and solid-predominant subtypes (28.6%; P=0.001). Patients having a micropapillary component had a significantly higher occult nodal metastasis rate (24.2%) compared with no micropapillary component (P=0.007). Histological subtype with micropapillary component and all preoperative predictors were significant prognostic factors affecting disease-free survival (DFS) (all P<0.05).

Conclusions

A novel approach to predict occult nodal metastasis was developed for peripheral clinical stage I lung adenocarcinoma. It would be helpful for selecting candidates for stereotactic ablative radiotherapy (SABR) or wedge resection and mediastinoscopy or endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA). Complete nodal dissection should be performed for moderate to high-risk patients or patients with poor histologic subtypes.

Histopathologic analysis of brain metastasis in pulmonary adenocarcinoma: Necrosis is a new risk factor

BACKGROUND

Studies have shown that 30-50% of non-small cell lung cancer (NSCLC) patients develop brain metastasis (BM). Since BM shortens overall survival and decreases the quality of life, early detection and treatment of BM are vital. While data are available for clinical risk factors of NSCLC with BM, histopathological factors are not well understood. Therefore, we evaluated the histopathological related factors which will help early detection and selection of effective treatment options.

MATERIALS AND METHODS

A total of 117 surgical lung specimens diagnosed as NSCLC with BM were included as a study group. We included 237 cases without BM as a control group. One pathologist reviewed H&E slides and analyzed the histopathologic factors of all cases.

RESULTS

In pulmonary adenocarcinoma, vascular invasion, N stage, micropapillary pattern and necrosis were significantly associated with BM in multivariate analysis (vascular invasion, p = 0.009; micropapillary pattern, p = 0.024; others, p < 0.001). Tumor with extensive necrosis had higher hazard ratio and shorter time to BM (p < 0.001).

CONCLUSION

Our findings suggest that necrosis is a new predictive factor of BM in pulmonary adenocarcinoma. Short term follow-up is needed especially when extensive necrosis is present.

[Research Progress of Lymph Node Micrometastasis in Non-small Cell Lung Cancer]

The incidence and mortality of lung cancer rank top in China. One important factor is the occurrence of metastasis. With the development of science technology, the effect of surgical treatment on lung cancer is improved. Moreover, the use of targeted therapy has achieved a new height for the treatment of lung cancer. However, the recurrence rate remains high even the tumor was completely resected at early stage. The occurrence of lymph node micrometastasis is considered as one of the plausible explanations. The difficulty indetecting micrometastasis has been greatly reduced. Although studies dig deeper into the lymph node micrometastasis, there are still some controversies including the selection of surgical procedures, the pathological staging and prognosis about patients with lymph node micrometastasis. This review manages to generalize the latest research progress of lymph node micrometastasis.
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Lepidic, Papillary Components and EGFR Mutations are Frequent in Patients With Lung Adenocarcinoma Who are Over 75 Years Old

Treatment for lung adenocarcinoma frequently diverges from standard treatment in older patients. Clinical, pathologic, and molecular characteristics of lung cancer in patients over 75 years old have not been fully described. The aim of our work was to describe the rate of EGFR, KRAS, BRAF, and HER2 mutations, and ALK rearrangement and pathologic characteristics in patients with lung adenocarcinoma over 75, compared with patients below 75 years old. This is a retrospective study from 2 cohorts: a histopathologic cohort of all consecutively resected lung adenocarcinoma in our institution for patients over 75 (n=54, from 2006 to 2017) compared with patients below 75 years old (n=148, from 2014 to 2017) and a molecular cohort of all stage IIIb or IV lung adenocarcinoma from 2009 to 2017 (n=1611). Papillary and lepidic components were more frequently found in patients over 75 years old (P=0.046 and 0.0078, respectively). The rate of current smokers was lower in older patients (P<0.0001). EGFR mutations were more frequent in patients over 75 than in younger patients: 17% versus 8.1% (P<0.0001). The mutually exclusive KRAS mutation was more frequent in patients below 75 years old than in older patients: 25.8% versus 12.8% (P<0.0001). There was no difference for the proportion of the 2 most frequent EGFR mutations (exon 19 deletion and L858R mutation) (P=0.85) or KRAS-mutated codon (P=0.22) between tumors in younger or older patients. There was no statistically significant difference for the presence of BRAF, HER2 mutations, and ALK rearrangement (P=0.44, 0.71, and 1, respectively). Our work highlights the fact that EGFR mutations are more frequent in patients over 75 years old in our population. We can hypothesize that this difference might be mainly caused by the less frequent occurrence of tobacco-smoking-related lung cancers in the elderly and the presence of a lepidic or papillary component in this age group.

Appropriate lymphadenectomy significantly reduced recurrence after segmentectomy for patients with non-small cell lung cancer

Background

Segmentectomy has been widely used for small-sized non-small cell lung cancer (NSCLC). The objective of this study is to determine the impact of number of harvested lymph nodes (LNs) on survival for patients undergoing segmentectomy.

Methods

The clinicopathologic data of patients undergoing segmentectomy for NSCLC from July 2011 to December 2014 were retrospectively analyzed. Survival analysis was performed by Kaplan-Meier method and Cox regression analysis.

Results

A total of 259 patients with NSCLC were eligible for analysis. Patients with harvested LN ≥6 had higher frequency of nodal metastasis in pathologic examination (9.4% vs. 1.5%, P=0.005). The 3-year recurrence-free survival (RFS) of patients with harvested LN ≥6 (90.2%) was significantly higher than that of patients with harvested LN <6 (73.7%, log-rank P=0.038). Multivariable Cox analysis identified harvested LN ≥6 as an independent predictor for improved RFS [hazard ratio (HR) =0.35; 95% confidence interval (CI): 0.14-0.90; P=0.029]. There was no significant difference in RFS between patients with harvested LN station ≥3 and <3 (log-rank P=0.34).

Conclusions

The number of harvest LN ≥6 was independently associated with improved RFS for NSCLC patients undergoing segmentectomy, supporting the National Comprehensive Cancer Network (NCCN) guidelines of appropriate LN sampling.

Protein overexpression and gene amplification of cellular mesenchymal-epithelial transition factor is associated with poor prognosis in micropapillary-predominant subtype pulmonary adenocarcinoma

Micropapillary-predominant subtype pulmonary adenocarcinoma (MPPAC) is a subtype of lung cancer with poor prognosis. Cellular mesenchymal-epithelial transition factor (c-MET) is a promising pharmaceutic target found to be associated with the survival of patients with pulmonary adenocarcinoma. In this study, we aimed to analyze c-MET protein overexpression and gene amplification in MPPAC samples and to elucidate their relationship with the clinicopathological characteristics of the patients. c-MET protein expression was examined by immunohistochemical analyses, and gene amplification was detected by fluorescence in situ hybridization. A total of 86 MPPAC cases were included in this study. The prevalence of c-MET protein overexpression and gene amplification were 62.8% and 10.5%, respectively. C-MET protein overexpression was significantly associated with smoking status, lymphatic and venous invasion, and tumor-node-metastasis stage (P = .014, P = .040, and P = .004, respectively), but c-MET gene amplification showed no relation with any of these characteristics. Univariate analysis revealed that pleural invasion, lymph node metastasis, lymphatic and venous invasion, tumor-node-metastasis stage, c-MET protein overexpression, and c-MET gene amplification were associated with poor prognosis (P = .041, P < .001, P = .001, P < .001, P = .001 and P = .001, respectively), but only c-MET gene amplification was an independent prognostic marker (P = .04). These results indicated that c-MET is an important biomarker. Also, c-MET protein overexpression and gene amplification are highly related to poor prognosis in patients with MPPAC.