Missed Intrapulmonary Lymph Node Metastasis and Survival After Resection of Non-Small Cell Lung Cancer

Standardized intrapulmonary lymph node dissection in lung cancer specimens: A national Colombian analysis

Objective

In patients with non-small cell lung cancer, lymph node assessment is essential for appropriate staging. The intrapulmonary lymph nodes (IPLNs) should be considered when assigning the N stage but are infrequently evaluated in Colombian centers, resulting in understaging that may hinder optimal treatment.

Methods

We conducted a prospective study of IPLN dissection in patients with clinical stage I or II non-small cell lung cancer who underwent surgical resection at 9 institutions in Colombia between 2021 and 2023. IPLN dissection was performed by trained surgeons who collected lymph nodes from fresh specimens after resection and before formalin fixation.

Results

One hundred patients were eligible for the analysis. Their mean age was 67 ± 10.9 years, and 76% were women. Most (74%) had adenocarcinoma, 20% had neuroendocrine tumors, and 6% had squamous cell carcinoma. Successful sampling and histopathologic analysis of at least one IPLN station was obtained in 85% of patients, 9% had upstaging due to positive N2 lymph nodes, and 5% had upstaging due to positive N1 lymph nodes. Among the patients with pN0 or pN1 disease, 3.2% (3 out of 91) were upstaged exclusively due to positive IPLNs.

Conclusions

Fresh-specimen dissection to collect IPLNs is appropriate and feasible to achieve more accurate pathological staging in Colombian lung cancer patients. In clinical N0 patients, IPLN dissection maximizes selection for adjuvant therapy.

So Now We Know-Reflections on the Extent of Resection for Stage I Lung Cancer

Lobectomy has been the standard treatment for stage I lung cancer in healthy patients, largely based on a randomized trial published in 1995. Nevertheless, research has continued regarding the role of sublobar resection. Three additional randomized trials addressing resection extent in healthy patients have recently been published. These 4 trials involve differences in design, eligibility, interventions, and intraoperative processes. Patients were ineligible if intraoperative assessment demonstrated stage > IA or inadequate resection margins. All trials consistently show no differences in perioperative morbidity, mortality, and postoperative changes in lung function between sublobar resection and lobectomy-consistent with other nonrandomized evidence. Long-term outcomes are generally encouraging of lesser resection, but some inconsistencies are apparent. The 2 larger recent trials demonstrated no overall survival difference while the others suggested better survival after lobectomy versus sublobar resection. Recurrence-free survival was found to be the same after lobectomy versus sublobar resection in 3 trials, despite higher locoregional recurrences after sublobar resection. The low 5-year recurrence-free survival (64%, regardless of resection extent) in 1 recent trial highlights the need for further optimization. Thus, there is high-level evidence that sublobar resection is a reasonable alternative to lobectomy in healthy patients. However, variability in long-term results suggests that aspects of patients, tumors and interventions need to be better understood. Therefore, we propose to apply sublobar resection cautiously; especially because there are no short-term benefits. Sublobar resection requires careful attention to intraoperative details (nodes, margins), and may be best suited for less aggressive (eg, ground glass, slow growing) tumors.

Two Interventions on Pathologic Nodal Staging in a Population-Based Lung Cancer Resection Cohort

BACKGROUND

Despite its prognostic importance, poor pathologic nodal staging of lung cancer prevails. We evaluated the impact of 2 interventions to improve pathologic nodal staging.

METHODS

We implemented a lymph node specimen collection kit to improve intraoperative lymph node collection (surgical intervention) and a novel gross dissection method for intrapulmonary node retrieval (pathology intervention) in nonrandomized stepped-wedge fashion, involving 12 hospitals and 7 pathology groups. We used standard statistical methods to compare surgical quality and survival of patients who had neither intervention (group 1), pathology intervention only (group 2), surgical intervention only (group 3), and both interventions (group 4).

RESULTS

Of 4019 patients from 2009 to 2021, 50%, 5%, 21%, and 24%, respectively, were in groups 1 to 4. Rates of nonexamination of lymph nodes were 11%, 9%, 0%, and 0% and rates of nonexamination of mediastinal lymph nodes were 29%, 35%, 2%, and 2%, respectively, in groups 1 to 4 (P < .0001). Rates of attainment of American College of Surgeons Operative Standard 5.8 were 22%, 29%, 72%, and 85%; and rates of International Association for the Study of Lung Cancer complete resection were 14%, 21%, 53%, and 61% (P < .0001). Compared with group 1, adjusted hazard ratios for death were as follows: group 2, 0.93 (95% CI, 0.76-1.15); group 3, 0.91 (0.78-1.03); and group 4, 0.75 (0.64-0.87). Compared with group 2, group 4 adjusted hazard ratio was 0.72 (0.57-0.91); compared with group 3, it was 0.83 (0.69-0.99). These relationships remained after exclusion of wedge resections.

CONCLUSIONS

Combining a lymph node collection kit with a novel gross dissection method significantly improved pathologic nodal evaluation and survival.

Frequency and predictive factors of nodal micro-metastasis (NMM) in resectable non-small cell lung cancer

Background

The frequency of lymph nodal micrometastasis (NMM) in resectable non-small cell lung cancer (NSCLC) is frequently underestimated when relying solely on standard hematoxylin and eosin staining during pathological examination.

Methods

This is a retrospective cross-sectional diagnostic research. Medical records of resectable pN0 NSCLC patients who underwent curative resection in Maharaj Nakorn Chiang Mai Hospital between January 2006 to December 2017 were retrospectively reviewed. Immunohistochemistry (IHC) staining using cytokeratin AE1/AE3, p53 and BerEP4 markers was employed to detect NMM. Primary objective of this study was to determine frequency of NMM in pN0 resectable NSCLC.

Results

This study included 98 patients with pN0 NSCLC, of which 47 were male and 51 were female. NMM was detected in 21 of 98 patients (21.43%). Lymph node station 10 and 7 were the most common site of micrometastasis among patients with N1 and N2 micrometastasis, respectively. Cytokeratin AE1/AE3 was the most sensitive antibody in detecting micrometastasis in lymph nodes, identifying 25 out of 27 positive lymph nodes. Tumor size greater than 4 cm was a statistically significant predictive factor for NMM with risk ratio 6.69 [95% confidence interval (CI): 2.38-18.85, P<0.001].

Conclusions

NMM was identified in 21.43% of pN0 resectable NSCLC patients and tumor size greater than 4 cm is predictive factor for NMM.

Distinct impacts of radiological appearance on lymph node metastasis and prognosis based on solid size in clinical T1 non-small cell lung cancer

BACKGROUND

Solid nodules (SN) had more aggressive features and a poorer prognosis than part-solid nodules (PSN). This study aimed to evaluate the specific impacts of nodule radiological appearance (SN vs. PSN) on lymph node metastasis and prognosis based on solid size in cT1 non-small cell lung cancer (NSCLC).

METHODS

Patients with cT1 NSCLC who underwent anatomical resection between 2010 and 2019 were retrospectively screened. Univariable and multivariable logistic regression analyses were adopted to evaluate the associations between nodule radiological appearance and lymph node metastasis. The log-rank test and Cox regression analyses were applied for prognostic evaluation. The cumulative recurrence risk was evaluated by the competing risk model.

RESULTS

There were 958 and 665 NSCLC patients with PSN and SN. Compared to the PSN group, the SN arm had a higher overall lymph node metastasis rate (21.7% vs. 2.7%, P < 0.001), including nodal metastasis at N1 stations (17.7% vs. 2.1%), N2 stations (14.0% vs. 1.6%), and skip nodal metastasis (3.9% vs. 0.6%). However, for cT1a NSCLC, no significant difference existed between SN and PSN (0 vs. 0.4%, P = 1). In addition, the impacts of nodule radiological appearance on lymph node metastasis varied between nodal stations. Solid NSCLC had an inferior prognosis than part-solid patients (5-year disease-free survival: 79.3% vs. 96.2%, P < 0.001). The survival inferiority only existed for cT1b and cT1c NSCLC, but not for cT1a. Strikingly, even for patients with nodal involvement, SN still had a poorer disease-free survival (P = 0.048) and a higher cumulative incidence of recurrence (P < 0.001) than PSN. Specifically, SN had a higher recurrence risk than PSN at each site. Nevertheless, the distribution of recurrences between SN and PSN was similar, except that N2 lymph node recurrences were more frequent in solid NSCLC (28.21% vs. 7.69%, P = 0.041).

CONCLUSION

SN had higher risks of lymph node metastasis and poorer prognosis than PSN for cT1b and cT1c NSCLC, but not for cT1a. SN exhibited a greater proportion of N2 lymph node recurrence than PSN. SN and PSN needed distinct strategies for nodal evaluation and postoperative follow-up.

Association between number of dissected lymph nodes and survival in patients undergoing resection for clinical stage IA pure solid lung adenocarcinoma: a retrospective analysis

BACKGROUND

Lymph node dissection is essential for staging of pure solid lung adenocarcinoma and selection of treatment after surgical resection, particularly for stage I disease since the rate of lymph node metastasis can vary from 0 to 23.7%.

METHODS

We retrospectively screened all adult patients (18 years of age or older) who underwent lobectomy for pure solid cT1N0M0 lung adenocarcinoma between January 2015 and December 2017 at our center. Cox proportional hazard regression was used to assess the association between the number of dissected lymph nodes and recurrence-free survival (RFS) and to determine the optimal number of dissected lymph nodes.

RESULTS

The final analysis included 458 patients (age: 60.26 ± 8.07 years; 241 women). RFS increased linearly with an increasing number of dissected lymph nodes at a range between 0 and 9. Kaplan-Meier analysis revealed significantly longer RFS in patients with ≥ 9 vs. <9 dissected lymph nodes. In subgroup analysis, ≥ 9 dissected lymph nodes was not only associated with longer RFS in patients without lymph node metastasis (n = 332) but also in patients with metastasis (n = 126). In multivariate Cox proportional hazard regression, ≥ 9 dissected lymph nodes was independently associated with longer RFS (hazard ratio [HR], 0.43; 95% confidence interval [CI], 0.26 to 0.73; P = 0.002).

CONCLUSIONS

≥9 Dissected lymph nodes was associated with longer RFS; accordingly, we recommend dissecting 9 lymph nodes in patients undergoing lobectomy for stage IA pure solid lung adenocarcinoma.

Validation of the IASLC Residual Tumor Classification in Patients With Stage III-N2 Non-Small Cell Lung Cancer Undergoing Neoadjuvant Chemoradiotherapy Followed By Surgery

OBJECTIVE

The aim of this study was to validate the International Association for the Study of Lung Cancer (IASLC) residual tumor classification in patients with stage III-N2 non-small cell lung cancer (NSCLC) undergoing neoadjuvant concurrent chemoradiotherapy (nCCRT) followed by surgery.

BACKGROUND

As adequate nodal assessment is crucial for determining prognosis in patients with clinical N2 NSCLC undergoing nCCRT followed by surgery, the new classification may have better prognostic implications.

METHODS

Using a registry for thoracic cancer surgery at a tertiary hospital in Seoul, Korea, between 2003 and 2019, we analyzed 910 patients with stage III-N2 NSCLC who underwent nCCRT followed by surgery. We classified resections using IASLC criteria: complete (R0), uncertain (R[un]), and incomplete resection (R1/R2). Recurrence and mortality were compared using adjusted subdistribution hazard model and Cox-proportional hazards model, respectively.

RESULTS

Of the 96.3% (n = 876) patients who were R0 by Union for International Cancer Control (UICC) criteria, 34.5% (n = 3O2) remained R0 by IASLC criteria and 37.6% (n = 329) and 28% (n = 245) migrated to R(un) and R1, respectively. Most of the migration from UICC-R0 to lASLC-R(un) and IASLC-R1/R2 occurred due to inadequate nodal assessment (85.5%) and extracapsular nodal extension (77.6%), respectively. Compared to R0, the adjusted hazard ratios in R(un) and R1/R2 were 1.20 (95% confidence interval, 0.94-1.52), 1.50 (1.17-1.52) ( P fortrend = .001) for recurrence and 1.18 (0.93-1.51) and 1.51 (1.17-1.96) for death ( P for trend = .002).

CONCLUSIONS

The IASLC R classification has prognostic relevance in patients with stage III-N2 NSCLC undergoing nCCRT followed by surgery. The IASLC classification will improve the thoroughness of intraoperative nodal assessment and the completeness of resection.

Standard Lymphadenectomy for Esophageal and Lung Cancer: Variability in the Number of Examined Lymph Nodes Among Pathologists and Its Survival Implication

AIM

We compared variability in number of examined lymph nodes between pathologists and analyzed survival implications in lung and esophageal cancer after standardized lymphadenectomy.

METHODS

Outcomes of 294 N2 dissected lung cancer patients and 132 2-field dissected esophageal cancer patients were retrospectively examined. The primary outcome was difference in reported lymph node count among pathologists. Secondary outcomes were overall and disease-specific survival related to this count and survival related to the 50% probability cut-off value of detecting metastasis based on the number of examined lymph nodes.

RESULTS

The median number of examined lymph nodes in lung cancer was 13 (IQR 9-17) and in esophageal cancer it was 22 (18-29). The pathologist with the highest median number of examined nodes had > 50% higher lymph node yield compared with the pathologist with the lowest median number of nodes in lung (15 vs. 9.5, p = 0.003), and esophageal cancer (28 vs. 17, p = 0.003). Survival in patients stratified by median reported lymph node count in both lung (adjusted RMST ratio < 14 vs. ≥ 14 lymph nodes 0.99, 95% CI 0.88-1.10; p = 0.810) and esophageal cancer (adjusted RMST ratio < 25 vs. ≥ 25 lymph nodes 0.95, 95% CI 0.79-1.15, p = 0.612) was similar. The cut-off value for 50% probability of detecting metastasis by number of examined lymph nodes in lung cancer was 15.7 and in esophageal cancer 21.8. When stratified by this cut-off, no survival differences were seen.

CONCLUSION

The quality of lymphadenectomy based on lymph node yield is susceptible to error due to detected variability between pathologists in the number of examined lymph nodes. This variability in yield did not have any survival effect after standardized lymphadenectomy.

Radiomics nomogram integrating intratumoural and peritumoural features to predict lymph node metastasis and prognosis in clinical stage IA non-small cell lung cancer: a two-centre study

AIM

To investigate the value of a radiomics nomogram integrating intratumoural and peritumoural features in predicting lymph node metastasis and overall survival (OS) in patients with clinical stage IA non-small-cell lung cancer (NSCLC).

MATERIALS AND METHODS

This study retrospectively enrolled 199 patients (training cohort: 71 patients from Affiliated Tumour Hospital of Nantong University; internal validation cohort: 46 patients from Affiliated Tumour Hospital of Nantong University; external validation cohort: 82 patients from the public database). CT radiomics models were constructed based on four volumes of interest: gross tumour volume (GTV), gross and 3 mm peritumoural volume (GPTV₃), gross and 6 mm peritumoural volume (GPTV₆), and gross and 9 mm peritumoural volume (GPTV₉). The optimal radiomics signature was further combined with independent clinical predictors to develop a nomogram. Univariable and multivariable Cox regression analysis were applied to determine the relationship between factors and OS.

RESULTS

GPTV₆ radiomics yielded better performance than GTV, GPTV₃, and, GPTV₉ radiomics in the training (area under the curve [AUC], 0.81), internal validation (AUC, 0.79), and external validation cohorts (AUC, 0.71), respectively. The nomogram integrating GPTV₆ radiomics and spiculation improved predictive ability, with AUCs of 0.85, 0.80, and 0.74 in three cohorts, respectively. Pathological lymph node metastasis, nomogram-predicted lymph node metastasis, and pleural indentation were independent risk predictors of OS (p<0.05).

CONCLUSIONS

The nomogram integrating GPTV₆ radiomics features and independent clinical predictors performed well in predicting lymph node metastasis and prognosis in patients with clinical stage IA NSCLC.

Maximizing lymph node dissection from fresh lung cancer specimens

Evaluation of lymph nodes during lung cancer resection is essential for pathologic staging and adjuvant treatment decisions. We developed a standardized approach for grossing resected lobes and segments to better assign the N1 category to hilar and peripheral lymph nodes. Lung specimens were dissected centrifugally from the bronchial stump, and all lymph nodes at the segmental and subsegmental bifurcations were removed. When combined with mediastinal lymph node dissection, this approach will likely maximize the number of lymph nodes analysed and improve the accuracy of pathologic N descriptor classification.

Clinical impact of number of lymph nodes dissected on postoperative survival in node-negative small cell lung cancer

OBJECTIVES

Small cell lung cancer (SCLC) is a lethal histologic subtype of lung cancer. Although the Commission on Cancer recommends pathological examination of at least 10 lymph nodes dissected (LNDs) for resected early-stage non-small cell lung cancer, its survival benefit of LNDs in patients with early-stage SCLC is unknown.

METHODS

The National Cancer Database was queried for SCLC patients with clinical stage I-II and clinical N0, NX disease per AJCC 7^th edition who had undergone lobectomy between 2004 and 2017. Overall survival of SCLC patients by the number of LNDs was compared using Log-rank tests. Univariate and multivariable Cox proportional hazards analyses were performed.

RESULTS

In total, 688 (42%), 311 (20%), 247 (16%), 196 (12%), 126 (8%), and 36 (2%) of 1,584 patients with early-stage SCLC had ≥10, 7-9, 5-6, 3-4, 1-2, and 0 LNDs, respectively. The sequential improvement in the HRs was no longer evident if the number of LNDs exceeds 4. Patients with ≥3 LNDs (n = 1,422) had a significantly longer overall survival than those with <3 LNDs (n = 162) (hazard ratio for death: 0.76, 95% confidence interval: 0.62-0.94, P = 0.0087). Multivariate analysis revealed that ≥3 LNDs was an independent factor for predicting overall survival (hazard ratio for death: 0.76, 95% confidence interval: 0.61-0.93, P = 0.0083).

CONCLUSIONS

Although we are reluctant to recommend a definitive "optimal number" of LNDs, our findings suggest the prognostic and therapeutic roles for performing ≥3 LNDs in patients with early-stage SCLC who undergo lobectomy.

Exploration of the optimal number of regional lymph nodes removed for resected N0 NSCLC patients: A population-based study

Background

The aim of our study was to explore the optimal number of regional lymph nodes removed (LNRs) in resected N0 non-small cell lung cancer (NSCLC) patients and identify potential risk factors.

Methods

Included in this study were 55,024 N0 NSCLC patients between 2004 and 2015 based on the Surveillance, Epidemiology, and End Results database (SEER). All the patients were divided into No LNR group (57.8%), 1-3 LNRs group (8.1%) and ≥4 LNRs group (31.4%). Relevant clinical and patient parameters including overall survival (OS), lung cancer-specific survival (LCSS), gender, race, year of diagnosis, primary site, T stage, AJCC stage, laterality, histological type, lymphadenectomy, radiation, chemotherapy, age at diagnosis, insurance status, marital status, family income.

Results

Kaplan-Meier analysis demonstrated LNRs had significantly better OS and LCSS than No LNRs in all the N0 NSCLC patients with different T stages (Logrank p<.001). Univariate and multivariate analysis showed that both OS and LCSS in ≥ 4 LNRs group were better than those in <1-3 LNRs group (OS: ≥4 LNRs group: HR, 0.583; 95%CI, 0.556-0.610; P<.001 vs.1-3 LNRs group: HR, 0.726; 95%CI, 0.687-0.769; P<.001; LCSS: ≥4 LNRs group: HR, 0.514; 95%CI, 0.480-0.550; P<.001 vs.1-3 LNRs group: HR, 0.647; 95%CI, 0.597-0.702; P<.001). In addition, whites, males, not upper lobe, large cell carcinoma and others, advance T stage or AJCC stage, no surgery, no LNR, no radiation, no chemotherapy, elder age at diagnosis, singled marital status and low family income had negative impact on prognosis of N0 NSCLC patients.

Conclusions

Our study suggests that ≥ 4 LNRs can yield better survival outcomes compared with 1-3 LNRs in N0 NSCLC patients.

A Comprehensive Comparison of Different Nodal Subclassification Methods in Surgically Resected Non-Small-Cell Lung Cancer Patients

INTRODUCTION

The revision of the N descriptor in non-small-cell lung cancer has been widely discussed in the past few years. Many different subclassification methods based on number or location of lymph nodes have been proposed for better distinguishing different N patients. This study aimed to systematically collect them and provide a comprehensive comparison among different subclassification methods in a large cohort.

METHOD

Pathological N1 or N2 non-small-cell lung cancer patients undergoing surgical resection between 2005 and 2016 in the Western China Lung Cancer Database were retrospectively reviewed. A literature review was conducted to collect previous subclassification methods. Kaplan-Meier and multivariable Cox analyses were used to examine the prognostic performance of subclassification methods. Decision curve analysis, Akaike's information criterion, and area under the receiver operating curve concordance were also performed to evaluate the standardized net benefit of the subclassification methods.

RESULTS

A total of 1625 patients were identified in our cohort. Eight subclassification methods were collected from previous articles and further grouped into subclassification based on number categories (node number or station number), location categories (lymph node zone or chain) or combination of number and location categories. Subclassification based on combination of lymph node location and number tended to have better discrimination ability in multivariable Cox analysis. No significant superiority among the different subclassification methods was observed in the three statistical models.

CONCLUSION

Subclassification based on the combination of location and number could be used to provide a more accurate prognostic stratification in surgically resected NSCLC and is worth further validation.

The impact of pathology grossing protocol measures to improve pathologic nodal staging in lung cancer

OBJECTIVE

Accurate assessment of lymph node (LN) status is essential for proper staging of resected lung cancer specimens. Here, we assessed pathology-centric interventions to increase the number of peribronchial LNs identified and evaluated in anatomic lung cancer resection specimens as part of a quality improvement initiative.

MATERIALS AND METHODS

All non-small cell lung cancer (NSCLC) anatomic resection specimens from 2017 to 2020 were evaluated, comprising two years pre-intervention and one year post-intervention. We instituted 3 measures to increase peribronchial LN yield: 1) educational grossing sessions for pathology assistants and residents, 2) directions to submit additional peribronchial tissue if no LNs were identified grossly, and 3) a hard-stop prior to sign-out by the attending pathologist if no peribronchial LNs were identified.

RESULTS

Of the total 227 resection specimens for NSCLC, 107/151 (70.9%) of specimens prior to the intervention had peribronchial LNs identified, whereas after the intervention significantly more (66/76, 86.8%, p < 0.01) specimens had peribronchial LNs identified. In addition, the mean number of peribronchial LNs identified significantly increased from 2.7 ± 3.3 pre-intervention to 4.3 ± 4.0 post-intervention (p < 0.001). Further analysis revealed a strong correlation between peribronchial LN metastases with both overall tumor size and invasive component size (for adenocarcinomas), correlation coefficient 0.974, p < 0.0001.

CONCLUSION

Establishing focused grossing measures by pathology led to a significant increase in the number of peribronchial LNs identified and assessed during histopathologic evaluation of anatomic lung cancer resection specimens. Larger tumors are more likely to have occult peribronchial LN metastases, which may warrant more aggressive peribronchial LN assessment for larger tumors.

Trends in Accuracy and Comprehensiveness of Pathology Reports for Resected NSCLC in a High Mortality Area of the United States

INTRODUCTION

Complete and accurate pathology reports are vital to postoperative prognostication and management. We evaluated the impact of three interventions across a diverse group of hospitals on pathology reports of postresection NSCLC.

METHODS

We evaluated pathology reports for patients who underwent curative-intent surgical resection for NSCLC, at 11 institutions within four contiguous Dartmouth Hospital Referral Regions in Arkansas, Mississippi, and Tennessee from 2004 to 2020, for completeness and accuracy, before and after the following three quality improvement interventions: education (feedback to heighten awareness); synoptic reporting; and a lymph node specimen collection kit. We compared the proportion of pathology reports with the six most important items for postoperative management (specimen type, tumor size, histologic type, pathologic [p] T-category, pN-category, margin status) across the following six patient cohorts: preintervention control, postintervention with four different combinations of interventions, and a contemporaneous nonintervention external control.

RESULTS

In the postintervention era, the odds of reporting all key items were eight times higher than those in the preintervention era (OR = 8.3, 95 % confidence interval [CI]: 6.7-10.2, p < 0.0001). There were sixfold and eightfold increases in the odds of accurate pT- and pN-category reporting in the postintervention era compared with the preintervention era (pT OR = 5.7, 95 % CI: 4.7-6.9; pN OR = 8.0, 95 % CI: 6.5-10.0, both p < 0.0001). Within the intervention groups, the odds of reporting all six key items, accurate pT category, and accurate pN-category were highest in patients who received all three interventions.

CONCLUSIONS

Gaps in the quality of NSCLC pathologic reportage can be identified, quantified, and corrected by rationally designed interventions.

Intrapulmonary lymph node (stations 13 and 14) metastasis in peripheral non-small cell lung cancer

It remains unknown whether dissecting the intrapulmonary lymph nodes (stations 13 and 14) when resecting peripheral non-small cell lung cancer (NSCLC) is necessary for accurate tumor node metastasis (TNM) staging. This study investigated intrapulmonary lymph node dissection (stations 13 and 14) on the pathological staging of peripheral NSCLC and the metastatic pattern of the lymph nodes.This retrospective study included patients with primary peripheral NSCLC who underwent radical dissection between January 2013 and December 2015. The clinical data of patients and examination results of intrapulmonary stations 12, 13, and 14 lymph nodes were analyzed.Of 3019 resected lymph nodes in a total of 234 patients (12.9/patient), 263 (8.7%) had metastasis. Ninety-nine patients had lymph node metastasis (42.3%): 40 (17.1%) were N1, 11 (4.7%) were N2, 48 (20.5%) were both N1 and N2, and 135 (57.7%) had no N1 or N2 metastasis. Sixteen (6.8%) patients had metastasis of stations 13 and/or 14. Metastasis in N1 positive patients of stations 10, 11, 12, 13, and 14 were 2.7%, 10.5%, 9.8%, 10.4%, and 8.5%, respectively. Missed detection without station 13 and 14 dissection was up to 6.8% (16/234).Dissection of stations 13 and 14 could be helpful for the identification of lymph node metastasis and for the accurate TNM staging of primary NSCLC.

The Evolving Concept of Complete Resection in Lung Cancer Surgery

Simple Summary

In the surgical treatment of lung cancer, the complete removal of the portion of the lung where the cancer is and of the involved adjacent structures is of paramount importance to achieve long-term survival. The International Association for the Study of Lung Cancer (IASLC) proposed a definition of complete resection that included a well-defined type of removal of the regional lymph nodes as a fundamental step. The lymph nodes may contain cancer cells and, if left behind, cancer will soon progress. The IASLC also defined incomplete resection when there is any evidence of persistent cancer after the operation. It also defined an intermediate condition, uncertain resection, when no evidence of residual disease can be proved, but all the conditions of complete resection are not fulfilled. Four validations of the definitions have proved their prognostic value and, therefore, the definitions should be followed when a surgical resection of lung cancer is planned.

Abstract

Different definitions of complete resection were formulated to complement the residual tumor (R) descriptor proposed by the American Joint Committee on Cancer in 1977. The definitions went beyond resection margins to include the status of the visceral pleura, the most distant nodes and the nodal capsule and the performance of a complete mediastinal lymphadenectomy. In 2005, the International Association for the Study of Lung Cancer (IASLC) proposed definitions for complete, incomplete and uncertain resections for international implementation. Central to the IASLC definition of complete resection is an adequate nodal evaluation either by systematic nodal dissection or lobe-specific systematic nodal dissection, as well as the integrity of the highest mediastinal node, the nodal capsule and the resection margins. When there is evidence of cancer remaining after treatment, the resection is incomplete, and when all margins are free of tumor, but the conditions for complete resection are not fulfilled, the resection is defined as uncertain. The prognostic relevance of the definitions has been validated by four studies. The definitions can be improved in the future by considering the cells spread through air spaces, the residual tumor cells, DNA or RNA in the blood, and the determination of the adequate margins and lymphadenectomy in sublobar resections.

Comparison of Lobectomy and Sublobar Resection for Stage IA Elderly NSCLC Patients (≥70 Years): A Population-Based Propensity Score Matching's Study

Background

To investigate the differences in survival between lobectomy and sub-lobar resection for elderly stage I non-small-cell lung cancer (NSCLC) patients using the Surveillance, Epidemiology, and End Results (SEER) registry.

Method

The data of stage IA elderly NSCLC patients (≥ 70 years) with tumors less than or equal to 3 cm in diameter were extracted. Propensity-matched analysis was used. Lung cancer-specific survival (LCSS) was compared among the patients after lobectomy and sub-lobar resection. The proportional hazards model was applied to identify multiple prognostic factors.

Results

A total of 3,504 patients met criteria after propensity score matching (PSM). Although the LCSS was better for lobectomy than for sub-lobar resection in patients with tumors ≤ 3 cm before PSM (p < 0.001), no significant difference in the LCSS was identified between the two treatment groups after PSM (p = 0.191). Multivariate Cox regression showed the elder age, male gender, squamous cell carcinoma (SQC) histology type, poor/undifferentiated grade and a large tumor size were associated with poor LCSS. The subgroup analysis of tumor sizes, histologic types and lymph nodes (LNs) dissection, there were also no significant difference for LCSS between lobectomy and sub-lobar resection. The sub-lobar resection was further divided into segmentectomy or wedge resection, and it demonstrated that no significant differences in LCSS were identified among the treatment subgroups either. Multivariate Cox regression analysis showed that the elder age, poor/undifferentiated grade and a large tumor size were a statistically significant independent factor associated with survival.

Conclusion

In terms of LCSS, lobectomy has no significant advantage over sub-lobar resection in elderly patients with stage IA NSCLC if lymph node assessment is performed adequately. The present data may contribute to develop a more suitable surgical treatment strategy for the stage IA elderly NSCLC patients.

The impact of an N1 lymph node examination in patients with early-stage non-small cell lung cancer: a retrospective cohort study

Background

The examination of lymph nodes (LNs) is critical for accurate node staging in patients with non-small cell lung cancer (NSCLC), but a consensus on the examinations of hilar and intrapulmonary (N1 station) LNs has not been reached. This study aimed to evaluate the role of LN dissection and pathological examination of N1 LN stations and their effects on survival in patients with stage IA-IIA NSCLC.

Methods

Data from patients pathologically staged as IA-IIA who underwent radical surgery and confirmed as lacking LN metastases from January 2008 to March 2018 were retrospectively reviewed. The Kaplan-Meier method was used to determine the overall survival (OS) and disease-free survival (DFS). After propensity score matching (PSM), a Cox model was used to determine the prognostic factors.

Results

Of the 1,935 patients investigated, the median number of N1 stations examined was 3. Patients with at least 2 N1 stations examined had apparently better OS (P=0.002) and DFS (P=0.001). All patients were divided into patients with 0–1 N1 station examined and patients with 2–5 N1 stations examined. After PSM, the number of N1 stations examined was an independent prognostic factor for DFS (P=0.004). Patients with 2–5 N1 stations examined experienced prolonged DFS (P=0.010). Patients in group 12 experienced prolonged OS (P=0.021) and DFS (P=0.026). Patients in group 13 or 14 experienced prolonged OS (P=0.028).

Conclusions

A larger extent of N1 station examination was associated with prolonged DFS in patients with stage IA-IIA NSCLC after lobectomy. The dissection and examination of at least 2 N1 stations included LNs from the lobar and segmental drainage fields.

A large real-world cohort study of examined lymph node standards for adequate nodal staging in early non-small cell lung cancer

BACKGROUND

The current National Comprehensive Cancer Network (NCCN) guidelines for non-small cell lung cancer (NSCLC) recommend that surgeons sample is not clear. We aimed to define a minimal number of examined lymph nodes for removal or sampling for optimized nodal staging recommendation, with a focus on T1-3N0M0 patients.

METHODS

A total of 55,101 consecutive patients were selected, including 52,099 patients with US Surveillance, Epidemiology, and End Results (SEER) data and 3,002 patients in a Chinese multicenter database from 11 thoracic referral centers, who underwent complete resection plus lymph node dissection or sampling for stage T1-3N0M0 NSCLC. Propensity score-matching analysis was performed with R software, and a cut-off value was calculated using X-tile software. Survival was evaluated using the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

Five-year survival rates with respect to total examined lymph nodes numbers (examined lymph nodes <10 vs. examined lymph nodes ≥10) were 69% and 64% (group A), 66% and 63% (group B), 62% and 58% (group C), 81% and 75% (group D). There were significant differences between examined lymph nodes <10 and examined lymph nodes >10 in each group (P<0.001).

CONCLUSIONS

A minimum of 10 examined lymph nodes would significantly improve T1-3N0M0 NSCLC prognosis and patients' survival rates if implemented as a minimum standard for lymphadenectomy. Therefore, we recommended a minimum of 10 examined lymph nodes for T1-3N0M0 patients.

Metastatic Patterns of Mediastinal Lymph Nodes in Small-Size Non-small Cell Lung Cancer (T1b)

Background: Lymph node metastasis (LNM) status is critical to the treatment. Fewer studies has focused on LNM in patients with small-size non-small cell lung cancer (NSCLC). This study aims to investigate clinicopathological characteristics associated with skip N2 (SN2) and non-skip N2 (NSN2) metastasis, and their metastatic patterns in NSCLC with tumor size of 1–2 cm.

Methods: We reviewed the records of NSCLC patients with tumor size of 1–2 cm who underwent lobectomy with systematic lymph node dissection (LND) between January 2013 and June 2019. Clinical, radiographical, and pathological characteristics were compared among N1, SN2, and NSN2 groups. Metastatic patterns of mediastinal lymph node were analyzed based on final pathology.

Results: A total of 63 NSCLC patients with tumor size of 1–2 cm were staged as pN2, including 25 (39.7%) SN2 and 38 (60.3%) NSN2. The incidence rates of SN2 and NSN2 were 2.8% (25/884) and 4.3% (38/884), respectively. For all clinicopathological characteristics, no significant difference was observed among the groups of N1, SN2, and NSN2. For the tumor located in each lobe, specific nodal drainage stations were identified: 2R/4R for right upper lobe; 2R/4R and subcarinal node (#7) for right middle lobe and right lower lobe; 4L and subaortic node (#5) for left upper lobe; #7 for left lower lobe. However, there were still a few patients (10.9%, 5/46) had the involvement of lower zone for tumors of upper lobe and the involvement of upper zone for lower lobe.

Conclusions: SN2 occurs frequently in patients with small-size NSCLC. Whether lobe-specific selective LND is suitable for all small-size patients deserves more studies to confirm. Surgeons should be more careful when performing selective LND for tumors located in the lower and upper lobes.

[Gefitinib inhibits glycolysis and induces programmed cell death in non-small cell lung cancer cells]

OBJECTIVE

To observe the cell death pattern induced by gefitinib in non-small cell lung cancer A549 and H1975 cells and explore the possible mechanism in light of glycolysis.

METHODS

The inhibitory effects of gefitinib at 20, 30, or 40 μmol/L in A549 cells and at 20, 40, or 80 μmol/L in H1975 cells were examined using MTT assay. The changes of lactic acid level in the cells were determined with a lactic acid kit, and the expression levels of glycolysis-related proteins (PKM2 and HK2) and the proteins in PI3K-Akt-mTOR signaling pathway were detected using Western blotting. 2-NBDG was used for detecting glucose uptake capacity of the cells, and ATP kit was used to detect the intracellular ATP level. The mitochondrial membrane potential of the cells was examined with the JC-1 kit, and cell apoptosis was analyzed with Annexin V-FITC/PI double staining. The relative expression levels of the apoptotic proteins Bax and Bcl-2 and the autophagy marker protein LC3B were detected with Western blotting.

RESULTS

MTT assay showed that gefitinib inhibited the proliferation of A549 and H1975 cells in a time- and dose-dependent manner (P &lt; 0.05). The IC₅₀ of gefitinib at 24, 48 and 72 h was 48.6, 28.6 and 19.7 μmol/L in A549 cells and was 321.6, 49.1 and 14.6 μmol/L in H1975 cells, respectively. Gefitinib significantly lowered intracellular lactic acid level of the cells (P &lt; 0.05) and down-regulated the expressions of PKM2 and HK2 proteins (P &lt; 0.05) and PI3K-Akt-mTOR signaling pathway-associated proteins (P &lt; 0.05). Gefitinib obviously inhibited glucose uptake and ATP levels in both A549 and H1975 cells (P &lt; 0.05). Treatment with gefitinib induced obviously enhanced apoptosis in the cells, resulting in apoptosis rates of (10.77± 1.0)%, (14.5±0.4)%, (17.4±0.2)% and (32.1±0.6)% at 0, 20, 30 and 40 μmol/L in A549 cells (P &lt; 0.05) and of (10.5±0.6)%, (13.2± 0.92)%, (18.9±0.98)% and (35.1±1.4)% at 0, 20, 40 and 80 μmol/L in H1975 cells, respectively (P &lt; 0.05). The protein expression of Bax increased and that of Bcl-2 decreased following gefitinib treatment in the cells (P &lt; 0.05). Gefitinib significantly increased autophagy in A549 and H1975 cells as shown by increased LC3B expressions following the treatment (P &lt; 0.05).

CONCLUSIONS

Gefitinib can inhibit the proliferation, induce apoptosis and increase autophagy in A549 and H1975 cells. Gefitinib induces apoptosis of the cells possibly by affecting glycolysis and PI3K-Akt-mTOR signaling pathway.

An Externally-Validated Dynamic Nomogram Based on Clinicopathological Characteristics for Evaluating the Risk of Lymph Node Metastasis in Small-Size Non-small Cell Lung Cancer

Background: Lymph node metastasis (LNM) status is of key importance for the decision-making on treatment and survival prediction. There is no reliable method to precisely evaluate the risk of LNM in NSCLC patients. This study aims to develop and validate a dynamic nomogram to evaluate the risk of LNM in small-size NSCLC.

Methods: The NSCLC ≤ 2 cm patients who underwent initial pulmonary surgery were retrospectively reviewed and randomly divided into a training cohort and a validation cohort as a ratio of 7:3. The training cohort was used for the least absolute shrinkage and selection operator (LASSO) regression to select optimal variables. Based on variables selected, the logistic regression models were developed, and were compared by areas under the receiver operating characteristic curve (AUCs) and decision curve analysis (DCA). The optimal model was used to plot a dynamic nomogram for calculating the risk of LNM and was internally and externally well-validated by calibration curves.

Results: LNM was observed in 12.0% (83/774) of the training cohort and 10.1% (33/328) of the validation cohort (P = 0.743). The optimal model was used to plot a nomogram with six variables incorporated, including tumor size, carcinoembryonic antigen, imaging density, pathological type (adenocarcinoma or non-adenocarcinoma), lymphovascular invasion, and pleural invasion. The nomogram model showed excellent discrimination (AUC = 0.895 vs. 0.931) and great calibration in both the training and validation cohorts. At the threshold probability of 0–0.8, our nomogram adds more net benefits than the treat-none and treat-all lines in the decision curve.

Conclusions: This study firstly developed a cost-efficient dynamic nomogram to precisely and expediently evaluate the risk of LNM in small-size NSCLC and would be helpful for clinicians in decision-making.

Independent risk factors for lymph node metastasis in 2623 patients with Non-Small cell lung cancer

PURPOSE

this study attempts to identify the independent risk factors that can predict lymph node metastasis for the patients with non-small cell lung cancer (NSCLC), and guide doctor adoption of individualized treatment for such patients.

MATERIALS AND METHODS

This study was approved by the Hospital's Ethics Committee and all patients had signed informed consent forms. We retrospectively reviewed NSCLC patients who had undergone surgical resection from December 2008 to December 2013.The statistical significance of evaluation variables and lymph node metastasis was determined with Pearson's Chi-square test. The risk factors of lymph node metastasis were determined through univariate and multivariate logistic regression analysis. And for the age and tumor diameter factors, optimal cutoff points were determined with a receiver operating characteristic analysis.

RESULTS

In the present study, a total of 2623 patients were included in the study, and 779 patients with lymph node metastasis. Three independent risk factors were identified: age, tumor diameter and Ki-67 index. We found that <65 years of age (Adjusted-OR:1.921), ≥2.85 cm of tumor diameter (Adjusted-OR:3.141), and 5%~25% in Ki-67 group (Adjusted-OR:2.137),≥25% (Adjusted-OR:3.341) were significant. Also we found that 307 patients with lymph node metastasis and the lymph node metastasis rate was 51.0%, when the age<65 years, Ki-67 index≥25%, and the tumor diameter≥2.85 cm. On the contrary, there were only 2 patients with lymph node metastasis, and the rate of lymph node metastasis was 5.1%.

CONCLUSION

Identifying three independent risk factors that predict lymph node metastasis in non-small cell patients, Among NSCLC patients in whom all three predictors were identified, and over a half of the patients showed lymph node metastasis.

Preoperative Prediction of Lymph Node Metastasis in Patients With Early-T-Stage Non-small Cell Lung Cancer by Machine Learning Algorithms

Background: Lymph node metastasis (LNM) is difficult to precisely predict before surgery in patients with early-T-stage non-small cell lung cancer (NSCLC). This study aimed to develop machine learning (ML)-based predictive models for LNM.

Methods: Clinical characteristics and imaging features were retrospectively collected from 1,102 NSCLC ≤ 2 cm patients. A total of 23 variables were included to develop predictive models for LNM by multiple ML algorithms. The models were evaluated by the receiver operating characteristic (ROC) curve for predictive performance and decision curve analysis (DCA) for clinical values. A feature selection approach was used to identify optimal predictive factors.

Results: The areas under the ROC curve (AUCs) of the 8 models ranged from 0.784 to 0.899. Some ML-based models performed better than models using conventional statistical methods in both ROC curves and decision curves. The random forest classifier (RFC) model with 9 variables introduced was identified as the best predictive model. The feature selection indicated the top five predictors were tumor size, imaging density, carcinoembryonic antigen (CEA), maximal standardized uptake value (SUV_max), and age.

Conclusions: By incorporating clinical characteristics and radiographical features, it is feasible to develop ML-based models for the preoperative prediction of LNM in early-T-stage NSCLC, and the RFC model performed best.

Lymph node assessment in early stage non-small cell lung cancer lymph node dissection or sampling?

Lymph node assessment is an essential component of the treatment of lung cancer. Identification of the correct "N" stage is important for staging which in turn determines treatment. Assessment of lymph nodes may be accomplished using imaging with CT scan and PET-CT, invasive techniques such as mediastinoscopy, endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) or endoscopic ultrasound fine needle aspiration (EUS-FNA). Ultimately, regardless of any pre-resection assessment, lymph nodes must be assessed at the time of resection. The question to be addressed in this report is the role of mediastinal lymph node dissection versus lymph node sampling. However, the issues surrounding lymph node assessment in NSCLC are complex, depending on clinical stage, imaging and histology.

Beyond Margin Status: Population-Based Validation of the Proposed International Association for the Study of Lung Cancer Residual Tumor Classification Recategorization

INTRODUCTION

The International Association for the Study of Lung Cancer's (IASLC's) proposal to recategorize the residual tumor (R) classification for resected NSCLC needs validation.

METHODS

Using a 2009 to 2019 population-based multi-institutional NSCLC resection cohort from the United States, we classified resections by Union for International Cancer Control (UICC) and IASLC R criteria and compared the distribution of R classification variables and their survival associations.

RESULTS

Of 3361 resections, 95.3% were R0, 4.3% were R1, and 0.4% were R2 by UICC criteria; 33.3% were R0, 60.8% were R-uncertain, and 5.8% were R1/2 by IASLC criteria; 2044 patients (63.8%) migrated from UICC R0 to IASLC R-uncertain. Median survival was not reached, 69 (95% confidence interval [CI]: 64-77), and 25 (95% CI: 18-36) months, respectively, for patients with IASLC R0, R-uncertain, and R1 or R2 resections. Failure to achieve nodal dissection criteria caused 98% of migration to R-uncertainty, metastasis to the highest mediastinal node station, 5.8%. Compared with R0, R-uncertain resections with mediastinal nodes, no mediastinal nodes, and no nodes had adjusted hazard ratios of 1.28 (95% CI: 1.10-1.48), 1.47 (95% CI: 1.24-1.74), and 1.74 (95% CI: 1.37-2.21), respectively, suggesting a dose-response relationship between nodal R-uncertainty and survival. Accounting for mediastinal nodal involvement, the highest mediastinal station involvement was not independently prognostic. The incomplete resection variables were uniformly prognostic.

CONCLUSIONS

The proposed R classification recategorization variables were mostly prognostic, except the highest mediastinal nodal station involvement. Further categorization of R-uncertainty by severity of nodal quality deficit should be considered.

Association of Pathologic Nodal Staging Quality With Survival Among Patients With Non-Small Cell Lung Cancer After Resection With Curative Intent

Importance

Pathologic nodal stage is the most significant prognostic factor in resectable non-small cell lung cancer (NSCLC). The International Association for the Study of Lung Cancer NSCLC staging project revealed intercontinental differences in N category-stratified survival. These differences may indicate differences not only in cancer biology but also in the thoroughness of the nodal examination.

Objective

To determine whether survival was affected by sequentially more stringent definitions of pN staging quality in a cohort of patients with NSCLC after resection with curative intent.

Design

This observational study used the Mid-South Quality of Surgical Resection cohort, a population-based database of lung cancer resections with curative intent. A total of 2047 consecutive patients who underwent surgical resection at 11 hospitals with at least 5 annual lung cancer resections in 4 contiguous US Dartmouth hospital referral regions in northern Mississippi, eastern Arkansas, and western Tennessee (>90% of the eligible population) were included. Resections were performed from January 1, 2009, through January 25, 2016. Survival was evaluated with the Kaplan-Meier method and Cox proportional hazards models.

Exposures

Eight sequentially more stringent pN staging quality strata included the following: all patients (group 1); those with complete resections only (group 2); those with examination of at least 1 mediastinal lymph node (group 3); those with examination of at least 10 lymph nodes (group 4); those with examination of at least 3 hilar or intrapulmonary and at least 3 mediastinal lymph nodes (group 5); those with examination of at least 10 lymph nodes, including at least 1 mediastinal lymph node (group 6); those with examination of at least 1 hilar or intrapulmonary and at least 3 mediastinal nodal stations (group 7); and those with examination of at least 1 hilar or intrapulmonary lymph node, at least 10 total lymph nodes, and at least 3 mediastinal nodal stations (group 8).

Main Outcomes and Measures

N category-stratified overall survival.

Results

Of the total 2047 patients (1046 men [51.1%] and 1001 women [48.9%]; mean [SD] age, 67.0 [9.6] years) included in the analysis, the eligible analysis population ranged from 541 to 2047, depending on stringency. Sequential improvement in the N category-stratified 5-year survival of pN0 and pN1 tumors was found from the least stringent group (0.63 [95% CI, 0.59-0.66] for pN0 vs 0.46 [95% CI, 0.38-0.54] for pN1) to the most stringent group (0.71 [95% CI, 0.60-0.79] for pN0 vs 0.60 [95% CI, 0.43-0.73] for pN1). The pN1 cohorts with 3 or more mediastinal nodal stations examined had the most striking survival improvements. More stringently defined mediastinal nodal examination was associated with better separation in survival curves between patients with pN1 and pN2 tumors.

Conclusions and Relevance

The prognostic value of pN stratification depends on the thoroughness of examination. Differences in thoroughness of nodal staging may explain a large proportion of intercontinental survival differences. More thorough nodal examination practice must be disseminated to improve the prognostic value of the TNM staging system. Future updates of the TNM staging system should incorporate more quality restraints.

Influence of Extent of Lymph Node Evaluation on Survival for Pathologically Lymph Node Negative Non-Small Cell Lung Cancer

OBJECTIVES

Despite previous retrospective reports that the number of lymph nodes resected at curative intent surgery for lung cancer correlates with overall survival (OS), no consensus exists regarding the minimal nor optimal number of lymph nodes to resect at curative lung cancer surgery.

METHODS

We studied subjects in the Surveillance Epidemiology and End Results Database (SEER) diagnosed with non-small cell lung cancer between 2000 and 2011 who underwent either lobectomy or pneumonectomy and had pathologic negative nodal evaluation. We excluded patients with sublobar resection and/or no lymph node evaluation. We examined associations between number of lymph nodes evaluated and OS/lung cancer-specific survival by multivariable Cox regression; and predictors of evaluation of more lymph nodes.

RESULTS

Among the 33,463 patients in our sample, a median of 7 lymph nodes were evaluated. We found that lung cancer-specific survival and OS improved with increasing lymph node evaluation up to 16 to 18 lymph nodes (hazard ratio, 0.77 [95% confidence interval, 0.70-0.85] and 0.78 [95% confidence interval, 0.72-0.86], respectively). There was little additional improvement in outcomes with evaluation of >16 to 18 lymph nodes. Blacks, Hispanics, females, and patients from distinct geographical regions were less likely to have 16 or more lymph nodes evaluated.

CONCLUSIONS

There was a consistently increasing survival benefit associated with a more extensive lymph node evaluation at lung cancer resection, up to 16 to 18 lymph nodes removed. The median number of nodes evaluated was, however, only 7, suggesting that setting a goal of ≥16 examined lymph nodes may lead to improved survival outcomes, and reduce disparities in care.

Role of low dose 256-slice CT perfusion imaging in predicting mediastinal lymph node metastasis of lung cancer

SUMMARY OBJECTIVE: CT perfusion (CTP) is an imaging technique that can be used to evaluate the changes in the microcirculation of tumor tissues. Our study aimed to investigate the role of CTP in predicting mediastinal lymph node metastasis. METHODS: Clinical data of 58 patients who received surgical resection of lung cancer and lymph node dissection in our hospital from June 2012 to December 2014 were collected. Patients were divided into a positive lymph node metastasis group and a negative lymph node metastasis group. Parameters of CTP, including peak enhancement intensity (PEI), perfusion value (PV), as well as blood volume (BV), were compared between the two groups. The receiver-operating characteristic (ROC) curve was used to predict mediastinal lymph node metastasis. RESULTS: The PV of the positive lymph node metastasis group was significantly higher than that of the negative group (p < 0.001). The ROC curve analysis showed that PV can be used as an index to predict mediastinal lymph node metastasis of lung cancer. The sensitivity and specificity of a PV greater than 7.5ml·min-1·ml-1 in predicting lymph node metastasis of lung cancer were 78.3 % and 91.4 %, respectively. CONCLUSION: The PV of low dose CT perfusion can be used as an index for predicting mediastinal lymph node metastasis of lung cancer.

Optimal Lymph Node Examination and Adjuvant Chemotherapy for Stage I Lung Cancer

OBJECTIVE

To determine the optimal number of lymph nodes (LNs) examined and the role of adjuvant chemotherapy in stage I lung cancer.

METHODS

The National Cancer Database was queried for surgically treated patients with pathologic stage I lung cancer between 2006 and 2014 (N = 65,438). The optimal LN numbers were determined in the multivariate Cox model and were further validated in the cohort with clinical stage I disease (N = 117,112) in terms of nodal upstaging and prognostic stratification. The role of adjuvant chemotherapy in patients with suboptimal staging (number of LNs examined was less than than the optimum) was evaluated in each T stage.

RESULTS

The number of LNs examined correlated with tumor size (p < 0.001). There were increasing survival benefits with each additional LN examined-up to eight, nine, 10, and 11 nodes for patients with T1a, T1b, T1c, and T2a, respectively. Validation from the cohort with clinically staged disease showed that the threshold of eight to 11 LNs was an independent predictor of nodal upstaging (OR = 1.706, 95% confidence interval [CI] 1.608-1.779) and survival outcome (hazard ratio = 0.890, 95% CI: 0.865-0.916). After propensity matching, adjuvant chemotherapy was associated with improved survival in patients with stage T2a disease having suboptimal staging (hazard ratio = 0.841, 95% CI: 0.714-0.990), but not in patients with stage T1a to T1c disease.

CONCLUSION

LN evaluation was important for accurate staging and adequate treatment, and examinations of an increasing number of nodes for progressively higher T components (i.e., eight, nine, 10, and 11 nodes for T1a, T1b, T1c, and T2a tumors, respectively) seemed crucial to predict upstaging and survival outcomes. Adjuvant chemotherapy might be beneficial to patients with stage T2a disease who have suboptimal nodal staging.

Impact of examined lymph node counts on survival of patients with stage IA non-small cell lung cancer undergoing sublobar resection

Background

The correlation between the number of examined lymph nodes (ELNs) and lung cancer-specific survival (LCSS) of stage IA non-small cell lung cancer (NSCLC) patients, who underwent sublobar resection in which lymph node (LN) sampling was relatively restricted as compared with standard lobectomy remains unclear.

Methods

Patients from the Surveillance, Epidemiology, and End Results database with stage IA NSCLC who underwent sublobar resection were categorized based on ELN count (1-6 vs. ≥7; the cut point 7 was identified by Cox model).

Results

Collectively, 3,219 patients with a median follow-up time of 37 months were included in this study (G1: 1-6 ELN, n=2,410; G2: ≥7 ELN, n=809). The 5-year LCSS rate of the G1 and G2 cohorts were 75% and 83%, respectively. Cox analysis suggested that the LCSS of G1 cohort patients was lower as compared with the G2 cohort [hazard ratio (HR) =1.530; 95% confidence interval (CI): 1.240-1.988, P<0.001). Propensity score analysis also showed decreased survival of the matched G1 cohort (HR =1.499; 95% CI: 1.176-1.911; P=0.001).

Conclusions

The data suggested the ELNs ≤6 were associated with poor prognoses. Adequate LN sampling is essential even for stage IA NSCLC patients undergoing sublobar resection.

Intrapulmonary lymph node metastasis is common in clinically staged IA adenocarcinoma of the lung

BACKGROUND

Intrapulmonary lymph nodes (LNs, stations 11-14) are usually omitted in postoperative pathological examination. Some non-small cell lung cancer (NSCLC) patients with intrapulmonary LN metastasis are incorrectly diagnosed as N0 cases. Furthermore, underestimation of intrapulmonary LN involvement in clinically early stage NSCLC may lead to the incorrect choice of surgical procedure: lobectomy or sublobar resection. This study was conducted to determine the status of intrapulmonary LN involvement in clinically staged IA (c-T1N0M0) peripheral adenocarcinoma of the lung.

METHODS

Seventy-five lobectomy specimens of c-T1N0M0 peripheral adenocarcinoma of the lung were carefully dissected to find intrapulmonary LNs. The longest diameter of each intrapulmonary LN was measured and sent for pathological examination, together with hilar and mediastinal LNs, to investigate the relationship between LN metastasis and primary tumor size.

RESULTS

Intrapulmonary LN metastasis was detected in 22.7%(17/75) of patients. Positive LNs were detected in 21.7% (10/46) of T1b patients and 45% (11/24) of T1c patients, while no metastasis (0/5) was observed in T1a patients (P = 0.036). The mean longest diameter of the 17 involved intrapulmonary LNs was only 6.5 ± 2.1 mm, which was not significantly different to the size of negative intrapulmonary LNs (5.2 ± 1.4 mm).

CONCLUSIONS

Intrapulmonary LN metastasis is common in clinically staged IA peripheral adenocarcinoma of the lung. LN metastasis is related to tumor size, and this should be taken into account to determine appropriate surgical procedures and postoperative treatment. Computed tomography is not a reliable method to judge LN metastasis, particularly intrapulmonary LN metastasis.

Tumor size and lymph node metastasis are prognostic markers of small cell lung cancer in a Chinese population

Small cell lung cancer (SCLC) is a high-grade neuroendocrine tumor characterized by rapid growth, early metastatic spread, and poor prognosis. This study aimed to explore the prognosis factors of survival in Chinese SCLC patients.A total of 78 patients with stage IIIA SCLC (mean age: 53.9 years, 65 males and 13 females) were enrolled in this retrospective study. At least of 5 years follow-up was performed.The survival time of these patients ranged from 1 month to 66 months with a median survival time of 11 months. Kaplan-Meier method with log-rank test was performed and showed that survival time in patients with tumor size ≤4 cm (median: 16 months) was significantly longer (P < .001) than that in patients with tumor size > 4 cm (median: 8 months); the median survival time of the patients with single lymph node metastasis was significantly longer than that in patients with multiple lymph node metastasis (P = .043). Combined multiple lymph node metastasis and tumor size >4 cm presented the worst survival outcome than others. Multivariate analysis by Cox Hazard model shows that the lymph node metastasis and tumors size were prognostic factors independent of age, sex, smoke, surgery, and treatment regimen (P < .05).Results showed that larger tumor size and multiple lymph node metastasis were associated with the poor survival in SCLC.

Effectiveness of Implemented Interventions on Pathologic Nodal Staging of Non-Small Cell Lung Cancer

BACKGROUND

Accurate pathologic nodal staging improves early stage non-small cell lung cancer survival. In an ongoing implementation study, we measured the impact of a surgical lymph node specimen collection kit and a more thorough pathologic gross dissection method on attainment of guideline-recommended pathologic nodal staging quality.

METHODS

We prospectively collected data on curative intent non-small cell lung cancer resections from 2009 to 2016 from 11 hospitals in four contiguous Dartmouth Hospital referral regions. We categorized patients into four groups based on exposure to the two interventions in our staggered implementation study design. We used χ² tests to examine the differences in demographic and disease characteristics and surgical quality criteria across implementation groups.

RESULTS

Of 2,469 patients, 1,615 (65%) received neither intervention; 167 (7%) received only the pathology intervention; 264 (11%) received only the surgery intervention; and 423 (17%) had both. Rates of nonexamination of lymph nodes reduced sequentially in the order of no intervention, novel dissection, kit, and combined interventions, including nonexamination of any lymph nodes and hilar/intrapulmonary and mediastinal nodes (p < 0.001 for all comparisons). The rates of attainment of National Comprehensive Cancer Network, Commission on Cancer, American Joint Committee on Cancer, and American College of Surgeons Oncology Group guidelines increased significantly in the same sequential order (p < 0.001 for all comparisons).

CONCLUSIONS

The combined effect of two interventions to improve pathologic lymph node examination has a greater effect on attainment of a range of surgical quality criteria than either intervention alone.

Eighth Edition Staging of Thoracic Malignancies: Implications for the Reporting Pathologist

Context The Staging and Prognostic Factors Committee of the International Association for the Study of Lung Cancer, in conjunction with the International Mesothelioma Interest Group, the International Thymic Malignancy Interest Group, and the Worldwide Esophageal Cancer Collaboration, developed proposals for the 8th edition of their respective tumor, node, metastasis (TNM) staging classification systems. Objective To review these changes and discuss issues for the reporting pathologist. Data Sources Proposals were based on international databases of lung (N = 94 708), with an external validation using the US National Cancer Database; mesothelioma (N = 3519); thymic epithelial tumors (10 808); and epithelial cancers of the esophagus and esophagogastric junction (N = 22 654). Conclusions These proposals have been mostly accepted by the Union for International Cancer Control and the American Joint Committee on Cancer and incorporated into their respective staging manuals (2017). The Union for International Cancer Control recommended implementation beginning in January 2017; however, the American Joint Committee on Cancer has deferred deployment of the eighth TNM until January 1, 2018, to ensure appropriate infrastructure for data collection. This manuscript summarizes the updated staging of thoracic malignancies, specifically highlighting changes from the 7th edition that are relevant to pathologic staging. Histopathologists should become familiar with, and start to incorporate, the 8th edition staging in their daily reporting of thoracic cancers henceforth.

Nowadays open-chest surgery in the era of fast-track management

In more than a century, approaches to perform thoracic surgical procedures have had profound changes. A milestone of those changes has been the advent of video-assisted techniques which rapidly evolved from minor diagnostic procedures to the performance by video-assisted thoracic surgery (VATS) of almost any major thoracic surgery. Nevertheless, indications remain for open chest procedures along with the fact that thoracotomy techniques have also evolved to minimally invasive ways, far different from the full thoracotomy of the past. This chapter reviews the evolution of open chest techniques and describes in detail present way to perform low invasiveness open chest surgery leading to excellent results through a mild postoperative course. Unsolved issues regarding the comparison of video-assisted and open techniques, particularly in lung cancer surgery are also considered.

Can mathematics replace anatomy to establish recommendations in lung cancer surgery?

The greater the number of lymph node (LN) sampled (NLNsS) during lung cancer surgery, the lower the risk of underestimating the pN-status and the better the outcome of the pN0-patients due to stage-migration. Thus, regarding LN sampling "to be or not to be", number is the question. Recent studies advocate removing 10 LNs. The most suitable NLNsS is unfortunately impossible to establish by mathematics. A too high NLNsS variability exists, based on anatomy, surgery and pathology. The methodology may vary according to Inter-institutional differences in the surgical approach regarding LN inspection and number sampling. The NLNsS increases with the type of resection: sublobar, lobectomy or pneumonectomy. Concerning pathology, one LN may be divided into several pieces, leading to number overestimation. The pathological examination is limited by the number of slices analyzed by LN. The examined LNs can arbitrarily depend on the probability of detecting nodal metastasis. In fact, the only way to ensure the best NLNsS and the best pN-staging is to remove all LNs from the ipsilateral mediastinal and hilar LN-stations as they are discovered by thoroughly dissecting their anatomical locations. In doing so, a deliberate lack of harvest of LNs is unlikely, number turns out not to be the question anymore and a low NLNsS no longer means incomplete surgery. This prevents from judging as incomplete a complete LN dissection in a patient with a small NLNsS and from considering as complete a true incomplete one in a patient with a great NLNsS. Precise information describing the course of the operation and furnished in the surgeon's reports is also advisable to further improve the quality of LN-dissection, which ultimately might be beneficial in the long-term to patients. However, that procedure is of limited interest in pN-staging if LNs are not thoroughly examined and also described by the pathologist.

Prognostic value of lymph node ratio in patients with pathological N1 non-small cell lung cancer: a systematic review with meta-analysis

BACKGROUND

Non-small cell lung cancer (NSCLC) patients with N1 disease have variable outcomes, and additional prognostic factors are needed. The number of positive lymph nodes (LNs) has been proposed as a prognostic indicator. However, the number of positive LNs depends on the number of LNs examined from the resection specimen. The lymph node ratio (LNR) can circumvent this limitation. The purpose of this study is to evaluate LNR as a predictor of survival and recurrence in patients with pathologic N1 NSCLC.

METHODS

We systematically reviewed studies published before March 17, 2016, on the prognostic value of LNR in patients with pathologic N1 NSCLC. The hazard ratios (HRs) and their 95% confidence intervals (CIs) were used to combine the data. We also evaluated heterogeneity and publication bias.

RESULTS

Five studies published between 2010 and 2014 were eligible for this systematic review with meta-analysis. The total number of patients included was 6,130 ranging from 75 to 4,004 patients per study. The combined HR for all eligible studies evaluating the overall survival (OS) and disease-free survival (DFS) of N1 LNR in patients with pathologic N1 NSCLC was 1.53 (95% CI: 1.22-1.85) and 1.64 (95% CI: 1.19-2.09), respectively. We found no heterogeneity and publication bias between the reports.

CONCLUSIONS

LNR is a worthy predictor of survival and cancer recurrence in patients with pathological N1 NSCLC.