Occult lymph node metastases in clinical N0/N1 NSCLC; A single center in-depth analysis

Primary lung adenocarcinoma harboring upper mediastinal lymphatic skip metastasis of cervical squamous cell carcinoma: A case report and literature review

The upper mediastinal lymph nodes are a rare site of metastasis in early-stage cervical cancer, but they are a common site of metastasis in lung cancer. Notably, standard approaches for identifying the source of metastasis and subsequent treatment are currently lacking. The present study describes the case of a patient with primary lung adenocarcinoma harboring upper mediastinal lymphatic skip metastasis from cervical squamous cell carcinoma 2 years after a radical hysterectomy. During video-assisted thoracoscopic surgery, it was indicated that the patient had a tendency for metastasis to the upper mediastinal lymph nodes from the lung tumor. Pathological examination confirmed the presence of metastasis; however, it was confirmed to originate from cervical carcinoma, rather than lung adenocarcinoma. In conclusion, for patients with lung cancer and concurrent malignancies, metastatic lymph nodes discovered during surgery may originate from the previous malignancy. Surgical management of oligometastatic lymph nodes in the mediastinum can be a potential treatment option, albeit one that may necessitate the integration of adjuvant treatment modalities as warranted by the individual case.

Quality of lymph node dissection and early recurrence in robotic versus thoracoscopic lobectomy for stage N1-2 non-small cell lung cancer: Eleven-year real-world data from a high-volume center

BACKGROUND

The efficacy of lymph node dissection (LND) and oncological outcomes of robot-assisted (RL) versus video-assisted thoracoscopic lobectomy (VL) for non-small cell lung cancer (NSCLC) with nodal involvement remains controversial. This study aims to compare LND quality and early recurrence (ER) rate between RL and VL for stage N1-2 NSCLC patients based on eleven-year real-world data from a high-volume center.

METHODS

Pathologic stage IIB-IIIB (T1-3N1-2) NSCLC patients undergoing RL or VL in Shanghai Chest Hospital from 2010 to 2021 were retrospectively reviewed from a prospectively maintained database. Propensity-score matching (PSM, 1:4 RL versus VL) was performed to mitigate baseline differences. LND quality was evaluated by adequate (≥16) LND and nodal upstaging rates. ER was defined as recurrence occurring within 24 months post-surgery.

RESULTS

Out of 1578 cases reviewed, PSM yielded 200 RL and 800 VL cases. Without compromising perioperative outcomes, RL assessed more N1 and N2 LNs and N1 stations, and led to higher incidences of adequate LND (58.5 % vs. 42.0 %, p < 0.001) and nodal upstaging (p = 0.026), compared to VL. Notably, RL improved perioperative outcomes for patients undergoing adequate LND than VL. Finally, RL notably reduced ER rate (22.0 % vs. 29.6 %, p = 0.032), especially LN ER rate (15.0 % vs. 21.5 %, p = 0.041), and prolonged disease-free survival (DFS; hazard ratio = 0.837, p = 0.040) compared with VL. Further subgroup analysis of ER and DFS within the cN1-2-stage cohort verified this survival benefit.

CONCLUSIONS

RL surpasses VL in enhancing LND quality, reducing ER rates, and improving perioperative outcomes when adequate LND is performed for stage N1-2 NSCLC patients.

The Society of Thoracic Surgeons Database Analysis: Comparing Sublobar Techniques in Stage IA Lung Cancer

BACKGROUND

This study compares sublobar resections-wedge resection and segmentectomy-in clinical stage IA lung cancers. It tests the hypothesis that overall survival after wedge resection is similar to segmentectomy.

METHODS

Adults undergoing wedge resection or segmentectomy for clinical stage IA lung cancer were identified from The Society of Thoracic Surgeons General Thoracic Surgery Database. Eligible patients were linked to the Centers for Medicare and Medicaid Services database using a matching algorithm. The primary outcome was long-term overall survival. Propensity scores overlap weighting (PSOW) adjustment of wedge resection using validated covariates was used for group difference mitigation. Kaplan-Meier and Cox regression models analyzed survival. All-cause first readmission, and morbidity and mortality were examined using PSOW regression models.

RESULTS

Of 9756 patients, 6141 met inclusion criteria, comprising 2154 segmentectomies and 3987 wedge resections. PSOW reduced differences between the groups. Unadjusted perioperative mortality was comparable, but wedge resection showed lower major morbidity rates. Weighted regression analysis indicated reduced mortality and major morbidity risks in wedge resection. Kaplan-Meier analysis revealed no mortality difference between groups, which was confirmed by PSOW Cox regression models. The cumulative risk of readmission was also comparable for both groups, with Cox Fine-Gray models showing no difference in rehospitalization risks.

CONCLUSIONS

In clinical stage IA lung cancer, relative to segmentectomy, wedge resection has comparable overall survival and lower perioperative morbidity, suggesting it is an equally effective option for the broader population of patients with clinical stage IA lung cancer, not only those at highest risk of complications.

Incidence rate of occult lymph node metastasis in clinical T1-2N0M0 small cell lung cancer patients and radiomic prediction based on contrast-enhanced CT imaging: a multicenter study : Original research

BACKGROUND

This study aimed to explore the incidence of occult lymph node metastasis (OLM) in clinical T1 - 2N0M0 (cT1 - 2N0M0) small cell lung cancer (SCLC) patients and develop machine learning prediction models using preoperative intratumoral and peritumoral contrast-enhanced CT-based radiomic data.

METHODS

By conducting a retrospective analysis involving 242 eligible patients from 4 centeres, we determined the incidence of OLM in cT1 - 2N0M0 SCLC patients. For each lesion, two ROIs were defined using the gross tumour volume (GTV) and peritumoral volume 15 mm around the tumour (PTV). By extracting a comprehensive set of 1595 enhanced CT-based radiomic features individually from the GTV and PTV, five models were constucted and we rigorously evaluated the model performance using various metrics, including the area under the curve (AUC), accuracy, sensitivity, specificity, calibration curve, and decision curve analysis (DCA). For enhanced clinical applicability, we formulated a nomogram that integrates clinical parameters and the rad_score (GTV and PTV).

RESULTS

The initial investigation revealed a 33.9% OLM positivity rate in cT1 - 2N0M0 SCLC patients. Our combined model, which incorporates three radiomic features from the GTV and PTV, along with two clinical parameters (smoking status and shape), exhibited robust predictive capabilities. With a peak AUC value of 0.772 in the external validation cohort, the model outperformed the alternative models. The nomogram significantly enhanced diagnostic precision for radiologists and added substantial value to the clinical decision-making process for cT1 - 2N0M0 SCLC patients.

CONCLUSIONS

The incidence of OLM in SCLC patients surpassed that in non-small cell lung cancer patients. The combined model demonstrated a notable generalization effect, effectively distinguishing between positive and negative OLMs in a noninvasive manner, thereby guiding individualized clinical decisions for patients with cT1 - 2N0M0 SCLC.

Role of invasive mediastinal nodal staging in survival outcomes of patients with non-small cell lung cancer and without radiologic lymph node metastasis: a retrospective cohort study

Background

Lung cancer diagnostic guidelines advocate for invasive mediastinal nodal staging (IMNS), but the survival benefits of this approach in patients with non-small cell lung cancer (NSCLC) without radiologic evidence of lymph node metastasis (rN0) remain uncertain. We aimed to investigate the impact of IMNS in patients with rN0 NSCLC by comparing the long-term survival between patients who underwent IMNS and those who did not (non-IMNS).

Methods

In this retrospective cohort study, we included patients with NSCLC but without radiologic evidence of lymph node metastasis from the Registry for Thoracic Cancer Surgery and the clinical data warehouse at the Samsung Medical Centre, Republic of Korea between January 2, 2008 and December 31, 2016. We compared the 5-year overall survival (OS) rate as the primary outcome after propensity score matching between the IMNS and non-IMNS groups. The age, sex, performance statue, tumor size, centrality, solidity, lung function, FDG uptake in PET-CT, and histological examination of the tumor before surgery were matched.

Findings

A total of 4545 patients (887 in the IMNS group and 3658 in the non-IMNS group) who received curative treatment for NSCLC were included in this study. By the mediastinal node dissection, the overall incidence of unforeseen mediastinal node metastasis (N2) was 7.2% (317/4378 patients). Despite the IMNS, 67% of pathological N2 was missed (61/91 patients with unforeseen N2). Based on propensity score matching, 866 patients each for the IMNS and non-IMNS groups were assigned. There was no significant difference in 5-year OS and recurrence-free survival (RFS) between two groups: 5-year OS was 73.9% (95% confidence interval, CI: 71%-77%) for IMNS and 71.7% (95% CI: 68.6%-74.9%; p = 0.23), for non-IMNS (hazard ratio, HR 0.90, 95% CI: 0.77-1.07), while 5-year RFS was 64.7% (95% CI: 61.5%-68.2%) and 67.5% (95% CI: 64.3%-70.9%; p = 0.35 (HR 1.08, 95% CI: 0.92-1.27), respectively. Moreover, the timing and locations of recurrence were similar in both groups.

Interpretation

IMNS might not be required before surgery for patients with NSCLC without LN suspicious of metastasis. Further randomised trials are required to validate the findings of the present study.

Funding

None.

Optimal Extent of Neck Dissection for a Head and Neck Lymph Node Metastasis from a Remote Primary Site

BACKGROUND

Despite its rarity and limited documentation, therapeutic neck dissection (ND) for cervical lymph node (LN) metastases from distant primary sites is increasingly practiced, potentially enhancing survival rates. However, the optimal ND extent remains unclear. This study aimed to determine the safety of excluding upper neck levels from ND.

METHODS

We retrospectively analyzed 25 patients who underwent ND for cervical LN metastases from remote primary tumors between 2015 and 2021 (12 with primary lung tumors, four with ovary, three with mammary gland, three with esophagus, two with thymus, and one with colon).

RESULTS

Assessing clinical characteristics and occult metastasis rates, we observed LN metastases predominantly at levels III and IV. Occult metastases occurred in 14 out of 25 patients, primarily at neck levels III and IV (55.0% and 50.0%, respectively). The five-year disease-specific survival rate for all patients was 44.3%. While no statistically significant impact of occult metastasis on prognosis was confirmed, an association between the postoperative LN ratio and poor prognosis was revealed.

CONCLUSIONS

Our findings suggest that prophylactic NDs at levels I, II, and Va may not be essential for managing cervical LN metastases from remote primary malignancies. This could lead to a more tailored and less invasive therapeutic strategy.

A 3 M Evaluation Protocol for Examining Lymph Nodes in Cancer Patients: Multi-Modal, Multi-Omics, Multi-Stage Approach

Through meticulous examination of lymph nodes, the stage and severity of cancer can be determined. This information is invaluable for doctors to select the most appropriate treatment plan and predict patient prognosis; however, any oversight in the examination of lymph nodes may lead to cancer metastasis and poor prognosis. In this review, we summarize a significant number of articles supported by statistical data and clinical experience, proposing a standardized evaluation protocol for lymph nodes. This protocol begins with preoperative imaging to assess the presence of lymph node metastasis. Radiomics has replaced the single-modality approach, and deep learning models have been constructed to assist in image analysis with superior performance to that of the human eye. The focus of this review lies in intraoperative lymphadenectomy. Multiple international authorities have recommended specific numbers for lymphadenectomy in various cancers, providing surgeons with clear guidelines. These numbers are calculated by applying various statistical methods and real-world data. In the third chapter, we mention the growing concern about immune impairment caused by lymph node dissection, as the lack of CD8 memory T cells may have a negative impact on postoperative immunotherapy. Both excessive and less lymph node dissection have led to conflicting findings on postoperative immunotherapy. In conclusion, we propose a protocol that can be referenced by surgeons. With the systematic management of lymph nodes, we can control tumor progression with the greatest possible likelihood, optimize the preoperative examination process, reduce intraoperative risks, and improve postoperative quality of life.

PET/CT based cross-modal deep learning signature to predict occult nodal metastasis in lung cancer

Occult nodal metastasis (ONM) plays a significant role in comprehensive treatments of non-small cell lung cancer (NSCLC). This study aims to develop a deep learning signature based on positron emission tomography/computed tomography to predict ONM of clinical stage N0 NSCLC. An internal cohort (n = 1911) is included to construct the deep learning nodal metastasis signature (DLNMS). Subsequently, an external cohort (n = 355) and a prospective cohort (n = 999) are utilized to fully validate the predictive performances of the DLNMS. Here, we show areas under the receiver operating characteristic curve of the DLNMS for occult N1 prediction are 0.958, 0.879 and 0.914 in the validation set, external cohort and prospective cohort, respectively, and for occult N2 prediction are 0.942, 0.875 and 0.919, respectively, which are significantly better than the single-modal deep learning models, clinical model and physicians. This study demonstrates that the DLNMS harbors the potential to predict ONM of clinical stage N0 NSCLC.

Occult lymph node metastasis is not a favorable factor for resected NSCLC patients

BACKGROUND

This study was to compare the clinical presentations and survivals between the non-small cell lung cancer (NSCLC) patients with occult lymph node metastasis (OLNM) and those with evident lymph node metastasis (ELNM). We also intended to analyze the predictive factors for OLNM.

METHODS

Kaplan-Meier method with log-rank test was used to compare survivals between groups. Propensity score matching (PSM) was used to reduce bias. The least absolute shrinkage and selection operator (LASSO)-penalized Cox multivariable analysis was used to identify the prognostic factors. Random forest was used to determine the predictive factors for OLNM.

RESULTS

A total of 2,067 eligible cases (N0: 1,497 cases; occult N1: 165 cases; evident N1: 54 cases; occult N2: 243 cases; evident N2: 108 cases) were included. The rate of OLNM was 21.4%. Patients with OLNM were tend to be female, non-smoker, adenocarcinoma and had smaller-sized tumors when compared with the patients with ELNM. Survival curves showed that the survivals of the patients with OLNM were similar to those of the patients with ELNM both before and after PSM. Multivariable Cox analysis suggested that positive lymph nodes (PLN) was the only prognostic factor for the patients with OLNM. Random forest showed that clinical tumor size was an important predictive factor for OLNM.

CONCLUSIONS

OLNM was not rare. OLNM was not a favorable sign for resected NSCLC patients with lymph node metastasis. PLN determined the survivals of the patients with OLNM. Clinical tumor size was a strong predictive factor for OLNM.

Endosonography With or Without Confirmatory Mediastinoscopy for Resectable Lung Cancer: A Randomized Clinical Trial

PURPOSE

Resectable non-small-cell lung cancer (NSCLC) with a high probability of mediastinal nodal involvement requires mediastinal staging by endosonography and, in the absence of nodal metastases, confirmatory mediastinoscopy according to current guidelines. However, randomized data regarding immediate lung tumor resection after systematic endosonography versus additional confirmatory mediastinoscopy before resection are lacking.

METHODS

Patients with (suspected) resectable NSCLC and an indication for mediastinal staging after negative systematic endosonography were randomly assigned to immediate lung tumor resection or confirmatory mediastinoscopy followed by tumor resection. The primary outcome in this noninferiority trial (noninferiority margin of 8% that previously showed to not compromise survival, Pnoninferior < .0250) was the presence of unforeseen N2 disease after tumor resection with lymph node dissection. Secondary outcomes were 30-day major morbidity and mortality.

RESULTS

Between July 17, 2017, and October 5, 2020, 360 patients were randomly assigned, 178 to immediate lung tumor resection (seven dropouts) and 182 to confirmatory mediastinoscopy first (seven dropouts before and six after mediastinoscopy). Mediastinoscopy detected metastases in 8.0% (14/175; 95% CI, 4.8 to 13.0) of patients. Unforeseen N2 rate after immediate resection (8.8%) was noninferior compared with mediastinoscopy first (7.7%) in both intention-to-treat (Δ, 1.03%; UL 95% CIΔ, 7.2%; Pnoninferior = .0144) and per-protocol analyses (Δ, 0.83%; UL 95% CIΔ, 7.3%; Pnoninferior = .0157). Major morbidity and 30-day mortality was 12.9% after immediate resection versus 15.4% after mediastinoscopy first (P = .4940).

CONCLUSION

On the basis of our chosen noninferiority margin in the rate of unforeseen N2, confirmatory mediastinoscopy after negative systematic endosonography can be omitted in patients with resectable NSCLC and an indication for mediastinal staging.

18F-FDG primary tumor uptake to improve N status prediction in cT1 non-metastatic non-small cell lung cancer: development and validation of a positron emission tomography model

Purpose

Occult lymph node involvement is a major issue in the management of non-small cell lung carcinoma (NSCLC), with an estimated prevalence of approximately 2.9-21.6% in 18F-FDG PET/CT series. The aim of the study is to construct a PET model to improve lymph node assessment.

Methods

Patients with a non-metastatic cT1 NSCLC were retrospectively included from two centers, one used to constitute the training set, the other for the validation set. The best multivariate model based on Akaike's information criterion was selected, considering age, sex, visual assessment of lymph node (cN0 status), lymph node SUVmax, primary tumor location, tumor size, and tumoral SUVmax (T_SUVmax). A threshold minimizing false pN0 prediction was chosen. This model was then applied to the validation set.

Results

In total, 162 patients were included (training set: 44, validation set: 118). A model combining cN0 status and T_SUVmax was selected (AUC 0.907, specificity at threshold: 88.2%). In the validation cohort, this model resulted in an AUC of 0.832 and a specificity of 92.3% versus 65.4% for visual interpretation alone (p = 0.02). A total of two false N0 predictions were noted (1 pN1 and 1 pN2).

Conclusion

Primary tumor SUVmax improves N status prediction and could allow a better selection of patients who are candidates for minimally invasive approaches.

Analysis of prognostic factors in pT1-2 N1 lung cancer patients in the light surgical results

Nodal metastasis status is an important parameter affecting the prognosis in lung cancer. Although surgical treatment is possible in most cases of N1 positive non-small cell lung cancer, this group of patients is clinically, radiologically and histologically heterogeneous. The aim of our study is to investigate the prognostic factors affecting survival in patients with pT1-2 N1 who underwent lung resection. From January 2010 to December 2019, patients who underwent lobectomy, bilobectomy or pneumonectomy for pT1-T2 N1 NSCLC in our center were included in the study. The preoperative, intraoperative and postoperative data of the patients were recorded by accessing the patient files and hospital records. The mean follow-up time was 39.8 months. The mean overall survival was 73.8 ± 3.6, and the mean disease-free survival was 67.5 ± 3.8. In multivariate analysis, age, N1 nodal metastasis pattern (occult vs obvious) and histology were found as independent variables affecting survival. In our study, age, histology, and clinical N1 status were found to be independent variables effective on overall survival.

18F-FDG PET/CT radiomics nomogram for predicting occult lymph node metastasis of non-small cell lung cancer

Purpose

To investigate the ability of a PET/CT-based radiomics nomogram to predict occult lymph node metastasis in patients with clinical stage N0 non-small cell lung cancer (NSCLC).

Materials and methods

This retrospective study included 228 patients with surgically confirmed NSCLC (training set, 159 patients; testing set, 69 patients). ITKsnap3.8.0 was used for image(CT and PET images) segmentation, AK version 3.2.0 was used for radiomics feature extraction, and Python3.7.0 was used for radiomics feature screening. A radiomics model for predicting occult lymph node metastasis was established using a logistic regression algorithm. A nomogram was constructed by combining radiomics scores with selected clinical predictors. Receiver operating characteristic (ROC) curves were used to verify the performance of the radiomics model and nomogram in the training and testing sets.

Results

The radiomics nomogram comprising six selected features achieved good prediction efficiency, including radiomics characteristics and tumor location information (central or peripheral), which demonstrated good calibration and discrimination ability in the training (area under the ROC curve [AUC] = 0.884, 95% confidence interval [CI]: 0.826-0.941) and testing (AUC = 0.881, 95% CI: 0.8031-0.959) sets. Clinical decision curves demonstrated that the nomogram was clinically useful.

Conclusion

The PET/CT-based radiomics nomogram is a noninvasive tool for predicting occult lymph node metastasis in NSCLC.

Lymph node micrometastasis in non-small cell lung cancer

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

Differentiation of Reactive Lymph Nodes and Tumor Metastatic Lymph Nodes With 68Ga-FAPI PET/CT in a Patient With Squamous Cell Lung Cancer

ABSTRACT

False-positive findings of mediastinal lymph node often confound the image interpretation of the preoperative PET/CT in non-small cell lung cancer. In this case, we reported 18F-FDG and 68Ga-FAPI PET/CT findings in a patient with squamous cell lung cancer. 18F-FDG-based TNM stage was stage IIIA (T1bN2M0) due to increased uptake in the enlarged right lower paratracheal lymph node. However, no abnormal 68Ga-FAPI uptake was observed in this lymph node. Subsequent histopathological examination revealed no evidence of malignancy in the mediastinal lymph nodes. Therefore, the tumor stage was downstaged to stage IA (T1bN0M0), which was in accordance with 68Ga-FAPI-based TNM stage.

Lung cancer staging, the established role of bronchoscopy

PURPOSE OF REVIEW

Lung cancer is the leading cause of cancer-related deaths worldwide. In the absence of distant metastases, accurate mediastinal nodal staging determines treatment approaches to achieve most favourable outcomes for patients. Mediastinal staging differentiates N0/N1 disease from N2/N3 in surgical candidates. Likewise, presence of nodal involvement in nonsurgical candidates who are being considered for stereotactic body radiation therapy is also critical. This review article seeks to discuss the current options available for mediastinal staging in nonsmall cell lung cancer (NSCLC), particularly the role of bronchoscopy.

RECENT FINDINGS

Although several techniques are available to stage the mediastinum, bronchoscopy with EBUS-TBNA with or without EUS-FNA appears to be superior in most clinical situations based on its ability to concomitantly diagnose and stage at once, safety, accessibility to the widest array of lymph node stations, cost and low risk of complications. However, training and experience are required to achieve consistent diagnostic accuracy with EBUS-TBNA.

SUMMARY

EBUS-TBNA with or without EUS-FNA is considered the modality of choice in the diagnosis and staging of NSCLC in both surgical and nonsurgical candidates.

The Value of a Systematic Protocol Using Endobronchial Ultrasound and Endoscopic Ultrasound in Staging of Lung Cancer for Patients with Imaging iN0–N1 Disease

<b><i>Introduction:</i></b> We hypothesize that systematic, combined, and multidisciplinary study of the mediastinum (endobronchial ultrasound [EBUS] and endoscopic ultrasound [EUS]) in patients with NSCLC with radiologically normal mediastinum improves the results of mediastinal staging obtained with EBUS alone. <b><i>Material and Methods:</i></b> A retrospective study of the prospective database collected on the patients with NSCLC with a radiologically normal mediastinum and an indication for systematic staging with EBUS and EUS. EBUS staging was followed by EUS in patients in which the results from the pathological analysis of EBUS were negative. <b><i>Results:</i></b> Forty-five patients were included in the analysis. The combination of EBUS followed by EUS provided better results than EBUS alone: sensitivity (S) 95% versus 80%, negative predictive value (NPV) 96.15% versus 86.21%, negative likelihood ratio 0.05 versus 0.20, and post-test probability 3.8% versus 13.8%. This represents an increase in S (15%), the validity index (6.6%), and NPV (9.9%) compared to EBUS alone. There were 4 false negatives (FNs) (8.8%) with the EBUS test alone. After adding EUS, 3 more cases were positive (6.6%) and only 1 FN (2.2%). <b><i>Conclusions:</i></b> In patients with NSCLC and a radiographically normal mediastinum, a systematic and combined staging with EBUS and EUS show higher sensitivity in the detection of mediastinal metastasis than with the use of EBUS alone. The high accuracy of the test means that the use of mediastinoscopy is not necessary to confirm the results in these patients. Since the availability of EUS is low, it may be advisable for the interventional pulmonologist to receive training in EUS-b.