The number of resected lymph nodes is associated with the long-term survival outcome in patients with T2 N0 non-small cell lung cancer

Establishing a prognostic scoring system and exploring prognostic value of examined lymph node numbers for stage I non-small cell lung cancer: a retrospective study of Surveillance, Epidemiology, and End Results (SEER) database and a Chinese cohort

Background

There is currently no recognized assessment system to predict disease outcomes for stage I non-small cell lung cancer (NSCLC). This research aimed to develop a prognostic scoring system for predicting 5-year overall survival (OS) of individuals with stage I NSCLC following definitive therapeutic intervention. Additionally, the optimal number of examined lymph nodes (ELNs) count for tumors no larger than 30 mm was determined.

Methods

Patients (n=22,617) diagnosed with stage I NSCLC from 2007 to 2015 who underwent definitive treatment (pulmonary lobectomy, pulmonary sublobectomy, or radiotherapy) were identified from the Surveillance, Epidemiology, and End Results (SEER) database. There were 400 Chinese patients with stage I NSCLC diagnosed in 2017 enrolled for external validation. The nomogram was constructed based on gradient boosting machine. The optimal ELNs in patients with tumors ≤30 mm and node-negative undergoing pulmonary lobectomy or pulmonary sublobectomy were determined using log-rank test and validated by multivariable analysis.

Results

Age at diagnosis, histology, differentiated grade, tumor staging, number of ELNs, and definitive treatment pattern were recognized as important factors for 5-year OS. The prognostic scoring system exhibited superior discrimination accuracy, calibration ability, and net clinical benefit compared to the tumor, node, metastasis (TNM) staging system. For patients with tumors ≤30 mm, more than 10 and 20 ELNs demonstrated the maximum OS difference during lobectomy and sublobectomy, respectively.

Conclusions

This prognostic scoring system will anticipate the prognosis of stage I NSCLC patients after radical treatment, thereby offering individualized treatment recommendations for both clinicians and patients. A minimum of 10 ELNs during lobectomy and 20 ELNs during sublobectomy are necessary for small-sized NSCLC.

Prognostic value of lymph node metrics in lung squamous cell carcinoma: an analysis of the SEER database

INTRODUCTION

Although the Tumor-Node-Metastasis (TNM) staging system is widely used for staging lung squamous cell carcinoma (LSCC), the TNM system primarily emphasizes tumor size and metastasis, without adequately considering lymph node involvement. Consequently, incorporating lymph node metastasis as an additional prognostic factor is essential for predicting outcomes in LSCC patients.

METHODS

This retrospective study included patients diagnosed with LSCC between 2004 and 2018 and was based on data from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute. The primary endpoint of the study was cancer-specific survival (CSS), and demographic characteristics, tumor characteristics, and treatment regimens were incorporated into the predictive model. The study focused on the value of indicators related to pathological lymph node testing, including the lymph node ratio (LNR), regional node positivity (RNP), and lymph node examination count (RNE), in the prediction of cancer-specific survival in LSCC. A prognostic model was established using a multivariate Cox regression model, and the model was evaluated using the C index, Kaplan-Meier, the Akaike information criterion (AIC), decision curve analysis (DCA), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI), and the predictive efficacy of different models was compared.

RESULTS

A total of 14,200 LSCC patients (2004-2018) were divided into training and validation cohorts. The 10-year CSS rate was approximately 50%, with no significant survival differences between cohorts (p = 0.8). The prognostic analysis revealed that models incorporating LNR, RNP, and RNE demonstrated superior performance over the TNM model. The LNR and RNP models demonstrated better model fit, discrimination, and reclassification, with AUC values of 0.695 (training) and 0.665 (validation). The RNP and LNR models showed similar predictive performance, significantly outperforming the TNM and RNE models. Calibration curves and decision curve analysis confirmed the clinical utility and net benefit of the LNR and RNP models in predicting long-term CSS for LSCC patients, highlighting their value in clinical decision-making.

CONCLUSION

This study confirms that RNP status is an independent prognostic factor for CSS in LSCC, with predictive efficacy comparable to LNR, with both models enhancing survival prediction beyond TNM staging.

Impact of the number of dissected lymph nodes on machine learning-based prediction of postoperative lung cancer recurrence: a single-hospital retrospective cohort study

BACKGROUND

The optimal number of lymph nodes to be dissected during lung cancer surgery to minimise the postoperative recurrence risk remains undetermined. This study aimed to elucidate the impact of the number of dissected lymph nodes on the risk of postoperative recurrence of non-small cell lung cancer (NSCLC) using machine learning algorithms and statistical analyses.

METHODS

We retrospectively analysed 650 patients with NSCLC who underwent complete resection. Five machine learning models were trained using clinicopathological variables to predict postoperative recurrence. The relationship between the number of dissected lymph nodes and postoperative recurrence was investigated in the best-performing model using Shapley additive explanations values and partial dependence plots. Multivariable Cox proportional hazard analysis was performed to estimate the HR for postoperative recurrence based on the number of dissected nodes.

RESULTS

The random forest model demonstrated superior predictive performance (area under the receiver operating characteristic curve: 0.92, accuracy: 0.83, F1 score: 0.64). The partial dependence plot of this model revealed a non-linear dependence of the number of dissected lymph nodes on recurrence prediction within the range of 0-20 nodes, with the weakest dependence at 10 nodes. A linear increase in the dependence was observed for ≥20 dissected nodes. A multivariable analysis revealed a significantly elevated risk of recurrence in the group with ≥20 dissected nodes in comparison to those with <20 nodes (adjusted HR, 1.45; 95% CI 1.003 to 2.087).

CONCLUSIONS

The number of dissected lymph nodes was significantly associated with the risk of postoperative recurrence of NSCLC. The risk of recurrence is minimised when approximately 10 nodes are dissected but may increase when >20 nodes are removed. Limiting lymph node dissection to approximately 20 nodes may help to preserve a favourable antitumour immune environment. These findings provide novel insights into the optimisation of lymph node dissection during lung cancer surgery.

Impact of lymphadenectomy extent on immunotherapy efficacy in postresectional recurred non-small cell lung cancer: a multi-institutional retrospective cohort study

BACKGROUND

Lymph node (LN) dissection is a common procedure for non-small cell lung cancer (NSCLC) to ascertain disease severity and treatment options. However, murine studies have indicated that excising tumor-draining LNs diminished immunotherapy effectiveness, though its applicability to clinical patients remains uncertain. Hence, the authors aim to illustrate the immunological implications of LN dissection by analyzing the impact of dissected LN (DLN) count on immunotherapy efficacy, and to propose a novel 'immunotherapy-driven' LN dissection strategy.

MATERIALS AND METHODS

The authors conducted a retrospective analysis of NSCLC patients underwent anti-PD-1 immunotherapy for recurrence between 2018 and 2020, assessing outcomes based on DLN count stratification.

RESULTS

A total of 144 patients were included, of whom 59 had a DLN count less than or equal to 16 (median, IQR: 11, 7-13); 66 had a DLN count greater than 16 (median, IQR: 23, 19-29). With a median follow-up time of 14.3 months (95% CI: 11.0-17.6), the overall median progression-free survival (PFS) was 7.9 (95% CI: 4.1-11.7) months, 11.7 (95% CI: 7.9-15.6) months in the combination therapy subgroup, and 4.8 (95% CI: 3.1-6.4) months in the immunotherapy alone subgroup, respectively. In multivariable Cox analysis, DLN count less than or equal to 16 is associated with an improved PFS in all cohorts [primary cohort: HR=0.26 (95% CI: 0.07-0.89), P =0.03]; [validation cohort: HR=0.46 (95% CI: 0.22-0.96), P =0.04]; [entire cohort: HR=0.53 (95% CI: 0.32-0.89), P =0.02]. The prognostic benefit of DLN count less than or equal to 16 was more significant in immunotherapy alone, no adjuvant treatment, pN1, female, and squamous carcinoma subgroups. A higher level of CD8+ central memory T cell (Tcm) within LNs was associated with improved PFS (HR: 0.235, 95% CI: 0.065-0.845, P =0.027).

CONCLUSIONS

An elevated DLN count (cutoff: 16) was associated with poorer immunotherapy efficacy in recurrent NSCLC, especially pronounced in the immunotherapy alone subgroup. CD8+Tcm proportions in LNs may also impact immunotherapy efficacy. Therefore, for patients planned for adjuvant immunotherapy, a precise rather than expanded lymphadenectomy strategy to preserve immune-depending LNs is recommended.

Impact of the Number of Harvested Lymph Nodes on Long-Term Survival in Node-Negative Non-Small-Cell Lung Cancer: Based on Clinical Stage But Not Pathological Stage

BACKGROUND

We aimed to investigate the impact of the number of harvested lymph nodes (LNs) on the overall survival (OS) and disease-free survival (DFS) of patients with clinical node-negative (cN0) non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

A total of 2247 patients with cN0 NSCLC between 2001 and 2014 were included. Scatter plots of hazard ratios from Cox proportional hazards models against the number of harvested LNs were created, and curves were fitted using a LOWESS smoother. Chow test was used to determine the cut-off points for the optimal number of harvested LNs. Long-term survival was compared between groups divided by the cut-off points.

RESULTS

The increasing numbers of harvested LNs and N2 level LNs were independent factors favoring OS and DFS. Seventeen LNs and 10 N2 level LNs were determined as the optimal cut-off points. The patients with ≥17 harvested LNs had a better OS (P = .001) and DFS (P = .002), while the patients with ≥10 harvested N2 level LNs also had a better OS (P < .001) and DFS (P = .001). The increasing numbers of harvested LNs and N2 level LNs were independent prognostic factors associated with prolonged OS and DFS only in patients with clinical T2 (cT2) NSCLC.

CONCLUSIONS

The increasing numbers of harvested LNs and N2 level LNs were associated with better OS and DFS in cN0 NSCLC patients that were suitable for lobectomies. At least 17 LNs and 10 N2 level LNs were required to be harvested, especially in cT2 patients.

A Systematic Review of Short-Term Outcomes of Minimally Invasive Thoracoscopic Surgery for Lung Cancer after Neoadjuvant Systemic Therapy

BACKGROUND

Minimally invasive surgeries for non-small cell lung cancers (NSCLCs) such as video-assisted thoracoscopic surgeries (VATSs) and robotic-assisted thoracoscopic surgeries (RATSs) have become standard of care for patients needing surgical resection in early stages. The role for neoadjuvant systemic therapy has increased with patients receiving neoadjuvant systemic chemotherapy and immunotherapy. However, there has been some equipoise over the intraoperative and overall outcomes for these patients. Here, we review the current data regarding outcomes of patients undergoing minimally invasive thoracic surgical resection after systemic chemotherapy, immunotherapy, or both.

METHODS

A systematic literature review of randomized controlled trials and observational studies presenting data on patients with NSCLC that underwent neoadjuvant systemic therapy followed by minimally invasive surgery was performed assessing complications, conversion rates, and lymph node yield.

RESULTS

Our search strategy and review of references resulted in 239 publications to screen with 88 full texts assessed and 21 studies included in our final review. VATS had a statistically significant higher lymph node yield in five studies. The reported conversion rates ranged from 0 to 54%. Dense adhesions, bleeding, and difficult anatomy were the most common reported reasons for conversion to open surgeries. The most common complications between both groups were prolonged air leak, arrythmia, and pneumonia. VATS was found to have significantly fewer complications in three papers.

CONCLUSIONS

The current literature supports VATS as safe and feasible for patients with NSCLC after neoadjuvant systemic treatment. Surgeons should remain prepared to convert to open surgeries in those patients with dense adhesions and bleeding risk.

Markers of Immune Cell Exhaustion as Predictor of Survival in Surgically-Treated Early-Stage NSCLC

Background

Tumor tissue as well as regional lymph nodes are removed during curative surgery for early-stage non-small cell lung cancer (NSCLC). These tissues provide a unique snapshot of the immune cell composition at the time of surgery. We investigated the immune landscape in matched tumor tissue, tumor bearing (tb) and non-tumor bearing (ntb) N1 as well as N2 lymph nodes (LNs) in patients with NSCLC and its relation to survival.

Methods

Internal hospital databases were screened for surgically treated NSCLC patients for whom tumor tissue, tbLNs as well as N1 and N2 ntbLNs were available. Clinical as well as demographic data were extracted from hospital records. Expression profiling of 770 immune-related genes was performed using the PanCancer IO 360 panel by NanoString Technologies.

Results

We identified 190 surgically treated patients of whom 16 fulfilled inclusion criteria and had sufficient archived tissue. The Tumor Immune Dysfunction and Exclusion (TIDE) score in N1 tumor-free lymph nodes was associated with OS. TIM-3 expression was inversely correlated with TIDE scores in affected LNs, N1 and N2 ntbLNs. Levels of CD8 expression were significantly higher in TIDE High compared to TIDE Low patients. TIM-3 and PD-L1 were selected for the final model for OS in multivariate regression in more than one tissue.

Conclusion

Levels of immune cell exhaustion markers may indicate a dysfunctional immune status and are associated with survival after curative surgery in NSCLC.

The association of nodal upstaging with surgical approach and its impact on long-term survival after resection of non-small-cell lung cancer

OBJECTIVES

Proponents of open thoracotomy (OPEN) and robot-assisted thoracic surgery (RATS) claim its oncological superiority over video-assisted thoracic surgery (VATS) in terms of the accuracy of lymph node staging.

METHODS

The National Cancer Database was queried for patients with non-small-cell lung cancer (NSCLC) undergoing lobectomy without neoadjuvant therapy from 2010 to 2014. Nodal upstaging rates were compared using a surgical approach. Overall survival adjusted for confounding variables was examined using the Cox proportional hazards model.

RESULTS

A total of 64 676 patients fulfilled the selection criteria. The number of patients who underwent lobectomy by RATS, VATS and OPEN approaches was 5470 (8.5%), 17 545 (27.1%) and 41 661 (64.4%), respectively. The mean number of lymph nodes examined for each of these approaches was 10.9, 11.3 and 10 (P < 0.01) and upstaging rates were 11.2%, 11.7% and 12.6% (P < 0.01), respectively. For patients with clinical stage I disease (N = 46 826; RATS = 4338, VATS = 13 416 and OPEN = 29 072), the mean lymph nodes examined were 10.6, 10.8 and 9.4 (P < 0.01), and upstaging rates were 10.8%, 11.1% and 12.1% (P < 0.01), respectively. A multivariable analysis suggested an association with improved survival with RATS and VATS compared with OPEN surgery [hazard ratio (HR) = 0.89 and 0.89, respectively; P < 0.01] for patients with all stages. In stage I disease, VATS but not RATS was associated with increased overall survival compared with the OPEN approach (HR = 0.81; P < 0.01).

CONCLUSIONS

RATS lobectomy is not superior to VATS lobectomy with respect to lymph node yield or upstaging of NSCLC. Increased nodal upstaging by the OPEN approach does not confer a survival advantage in any stage of NSCLC and may be associated with decreased overall survival.

Non-energy devices to dissect recurrent laryngeal nerve lymph nodes of non-small cell lung cancer under video-assisted thoracic surgery

Background

Systematic nodal dissection plays a crucial role in improving survival and staging in resectable non-small cell lung cancer (NSCLC) patients but at the cost of increasing the occurrence of recurrent laryngeal nerve injury. Technology should be improved to protect the recurrent laryngeal nerve (RLN) during surgery.

Methods

NSCLC patients who underwent video-assisted thoracic surgery (VATS) surgical treatment by the same surgeon at our hospital from January 2016 to December 2017 were included as the research subjects and were divided into an energy-device group and a non-energy-device group. Their procedures included anatomic pulmonary resection, normative N1 dissection, and systemic N2 dissection.

Results

The rate of metastatically involved recurrent laryngeal nerve lymph nodes (RLNLNs) was 5.19% (39/752). Dissection device, side of primary, FEV1, operative time and BMI were independent predictors of recurrent laryngeal nerve injury (RLNI) (hazard ratio (HR) = 3.576, 95% confidence interval (CI): 1.490–8.583, P = 0.004; HR = 0.175, 95% CI: 0.072–0.424, P =  < 0.001; HR = 3.008, 95% CI: 1.30–6.927, P = 0.010; HR = 0.328, 95% CI: 0.136–0.794, P = 0.013; HR = 0.344, 95%CI: 0.147–0.801, P = 0.013, respectively). Patients in the non-energy-device group had significantly less RLNI than the energy-device group (P = 0.016) and nearly half of the non-thermal RLNI recovered in 2 weeks (P = 0.025) whereas most thermal RLNI required 3 months for recovery.

Conclusions

Every station of RLNLN had some degree of cancer metastasis in NSCLC patients and when dissecting RLNLNs, dissection device was an independent and artificially controlled predictor of RLNI. Using a non-energy device is a feasible method to protect the RLN as well as an improved recovery time of RLNI.

Association between number of dissected lymph nodes and survival in stage IA non-small cell lung cancer: a propensity score matching analysis

BACKGROUND

For patients with stage IA non-small cell lung cancer (NSCLC) with tumor size ≤ 2 cm, the prognostic significance of the number of removed lymph nodes (NLNs) through different surgical methods remains unclear. To determine the association of NLNs with cancer-specific survival (CSS) and overall survival (OS) in patients with stage IA NSCLC with tumor size ≤ 2 cm who underwent different lung surgeries.

METHODS

We retrospectively enrolled 7293 patients from the Surveillance, Epidemiology and End Results database. Median NLNs was used to classify the patients into two groups: group A with NLNs ≤ 5 and group B with NLNs > 5. Propensity score matching (PSM) was performed to decrease selection bias. Kaplan-Meier analysis and Cox regression analysis were performed to identify the association between NLNs and survival outcomes.

RESULTS

Group B had better survival than group A in the unmatched cohort and matched cohort (all P < 0.05). Multivariable analyses revealed that the NLNs significantly affected CSS and OS of eligible cases in the unmatched cohort and matched cohort. Additionally, we found that the NLNs was a protective prognostic predictor of OS for patients who underwent wedge resection, segmental resection, or lobectomy.

CONCLUSION

The NLNs was a protective prognostic factor in NSCLC patients with tumor size ≤ 2 cm. We demonstrated that patients with > 5 NLNs in the cohort of wedge resection, segmental resection, or lobectomy exhibited a significantly better OS.

Alternative methods of lymph node staging in lung cancer: a narrative review

The nodal status indicator in non-small cell lung cancer is one of the most crucial prognostic factors available. However, there are still many arguments among scientists regarding whether the currently used nodal status descriptor should be changed in the forthcoming editions of the Tumor Node Metastasis classification or whether it is precise enough and should be maintained as is. We reviewed studies concerning nodal factor classifications to evaluate their accuracy in non-small cell lung cancer patients and to address the previously mentioned challenge. We reviewed the PubMed database regarding the following classifications: ongoing 8^th edition of the Tumor Node Metastasis classification, number of positive lymph nodes, number of negative lymph nodes, number of dissected lymph nodes, lymph node ratio, nodal chains, log odds of positive lymph nodes, zone-based classification and one that is based on the number of lymph node stations involved. Moreover, we analysed data regarding various combinations of these classifications. Our analysis showed that the present nodal staging may not accurately categorize every lung cancer patient. The number of positive lymph nodes and lymph node ratio or the log odds of positive lymph nodes (as the mathematical modification of lymph node ratio) are more legitimate, as they possess very robust data and should be considered initially as additional factors that can be incorporated in ongoing nodal staging systems. Forthcoming non-small cell lung cancer staging systems could benefit from the addition of quantitative-based parameters. Additionally, the minimal extent of lymphadenectomy should be established as staging benefits from it. International, prospective validation studies need to be performed to optimize the cut-off values and prognostic groups and to confirm the superiority of the newly suggested descriptors in non-small cell lung cancer nodal staging.

Combining node location and node ratio as a prognostic factor for surgical resected non-small cell lung cancer: a population-based study

Background

In the TNM system only the anatomic location is used to define nodal status. In this study we aim to evaluate the effectiveness of combining the location and ratio of metastatic lymph node (pN-NR) for the prognosis of non-small cell lung cancer (NSCLC).

Methods

Patients with pN1/pN2 NSCLC were retrieved from the SEER database. The optimal cut point of NR was determined with the maximal selecting test. All patients were divided into 4 categories with combination of pN (pN1 or pN2) and NR (low or high). The pN-NR was investigated as a predictor of overall survival (OS) and cause-specific survival (CSS) using Cox regression models. Survival curves were plotted using the Kaplan-Meier method and the difference was compared with log-rank test.

Results

A total of 12,170 patients were enrolled. The optimal cut point of NR was 0.3. Patients were divided into 4 groups: pN1-NR <0.3, pN1-NR ≥0.3, pN2-NR <0.3 and pN2-NR ≥0.3. The pN-NR was an independent prognostic factor for survival. Compared with pN1-NR <0.3, the hazard ratio of OS was 1.405 (95% CI: 1.295-1.524), 1.183 (95% CI: 1.113-1257) and 1.717 (95% CI: 1.607-1.835) times higher for pN1-NR ≥0.3, pN2-NR <0.3 and pN2-NR ≥0.3 group, respectively. The survival curves of OS separated well between the 4 pN-NR groups, with 5-year OS 47.1% for pN1-NR <0.3, 43.0% for pN2-NR <0.3, 35.0% for pN1-NR ≥0.3 and 28.5% for pN2-NR ≥0.3, and the P value between neighboring curves was statistically significantly. The same trend was observed for CSS. Subgroup analysis revealed similar results except the pneumonectomy group.

Conclusions

pN-NR could be a good predictor for the prognosis of NSCLC.

Restoration of miR-26b expression partially reverses the cisplatin resistance of NSCLC by targeting tafazzin

Background

Dysregulation of microRNAs has been reported to be responsible for drug resistance of cancers. However, the association between aberrant expression of miR-26b and cisplatin resistance in non-small cell lung cancer (NSCLC) remains unclear.

Methods

PC9 and A549 were used to establish the cisplatin resistance models on NSCLC. Expression of miR-26b in cisplatin-resistant PC9 and A549 cells (PC9/R and A549/R) was detected by quantitative real-time PCR assays. Drug sensitivity and mitochondrial apoptosis were detected by Cell Counting Kit-8 assay and flow cytometry assay, respectively. The target relationship between miR-26b and tafazzin (TAZ) was validated by dual-luciferase reporter assay.

Results

Obvious downregulation of miR-26b was observed in PC9/R and A549/R cells. Restoration of miR-26b partially reversed the cisplatin resistance of PC9/R and A549/R cells. Expression of TAZ was increased in PC9/R and A549/R cells compared to the parental PC9 and A549 cells. Results of dual-luciferase reporter assays verified that TAZ was targeted by miR-26b. We showed that restoration of miR-26b expression inhibited the TAZ expression and thus expanded the mitochondrial pathway of apoptosis induced by cisplatin in PC9/R and A549/R cells.

Conclusion

Restoration of miR-26b expression partially reverses the cisplatin resistance of NSCLC by targeting TAZ. miR-26b/TAZ axis may represent a potential strategy to reverse the cisplatin in NSCLC.

Nomograms for predicting overall survival and cancer-specific survival in patients with surgically resected intrahepatic cholangiocarcinoma

Purpose

To develop and validate nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) in patients with surgically resected intrahepatic cholangiocarcinoma (ICC).

Patients and methods

The nomograms were developed using a development cohort of 947 ICC patients after surgery selected from Surveillance, Epidemiology, and End Results database, and externally validated using a training cohort of 159 patients admitted at our institution. Nomograms for OS and CSS were established based on the independent prognostic factors identified by COX regression models and Fine and Grey’s models, respectively. The performance of the nomograms was validated internally and externally by using the concordance index (c-index), and calibration plot, and compared with that of AJCC 8th edition TNM staging system by using c-index and decision curve analysis.

Results

Age, T stage, M stage, lymph node ratio (LNR) level and tumor grade were independent prognostic predictors for OS in ICC patients, while T stage, M stage, LNR level and tumor grade were independent prognostic predictors for CSS. Nomogram predicting OS was with a c-index of 0.751 on internal validation and 0.725 up to external validation, while nomogram for CSS was with a c-index of 0.736 on internal validation and 0.718 up to external validation. Calibration plots exhibited that the nomograms-predicted and actual OS/CSS probabilities were fitted well on both internal and external validation. Additionally, the nomograms exhibited superiority over AJCC 8th edition TNM staging system with higher c-indices and net benefit gains, in predicting OS and CSS in ICC patients after surgery.

Conclusion

The constructed nomograms could predict OS and CSS with good performance, which could be served as an effective tool for prognostic evaluation and individual treatment strategies optimization in ICC patients after surgery in clinical practice.