Indications for invasive mediastinal staging in patients with early non-small cell lung cancer staged with PET-CT

Stereotactic body radiation therapy (SBRT) of centrally located medically inoperable early-stage non-small cell lung cancer (T1-T3N0M0) - A subgroup analysis of the expanded HILUS study

INTRODUCTION

Centrally located early-stage non-small cell lung cancer (ES NSCLC) with tumors close to the bronchi is potentially curable with stereotactic body radiation therapy (SBRT). To evaluate the clinical benefit of the treatment, both the risk of high-grade toxicity as well as the treatment efficacy need to be assessed.

MATERIAL AND METHODS

From the expanded HILUS cohorts, 72 patients with T1-T3N0M0 NSCLC were included in the current analysis. All patients had been treated with SBRT in 8 fractions to 56 Gy for a tumor located within 2 cm from the tracheobronchial tree. Primary endpoint was progression free survival (PFS) and secondary endpoints included pattern of failure, local control (LC), lung cancer-specific survival (LCSS), overall survival (OS) and toxicity. The Kaplan-Meier method and Cox regression analysis were used.

RESULTS

The median age of the cohort was 73 years and all patients suffered from comorbidities prior to SBRT. T2-T3 tumors were seen in 65 % of the patients. Seventeen patients relapsed after SBRT and distant recurrence was the most common form of relapse. Three-year PFS was 31 % (95 % CI 22-44) and largely explained by the short overall survival (38 % (95 % CI 22-44) at 3 years). Three-year rates of LC and LCSS were 97 % (95 % CI 92-100) and 76 % (95 % CI 65-89), respectively. Twelve patients (17 %) suffered from grade 5 toxicity, of which 9 were bronchopulmonary bleedings.

CONCLUSION

The severe toxic profile limits the clinical benefit using SBRT with the investigated approach for patients with centrally located ES NSCLC.

Diagnostic validity of combined transbronchial and transoesophageal ultrasound in positron emission tomography node-negative lung cancer

AIM

The role of invasive mediastinal diagnostic methods in lung cancer with negative positron emission tomography (PET) remains unclear. This study aimed to determine the sensitivity and negative predictive value (NPV) of combined endobronchial ultrasound (EBUS) and endoscopic ultrasound (EUS), referred to as combined ultrasound (CUS), for diagnosing N2 disease in this group of patients.

MATERIALS AND METHODS

single-centre study analysing medical records of clinical stage I to IVA lung cancer patients was conducted. All patients underwent positron emission tomography computed tomography (PET-CT), followed by CUS imaging and lung resection with systematic lymph node dissection. Pathological examination of lymph nodes was the reference standard.

RESULTS

Data from 596 patients were analysed. The prevalence of N2 disease was 8%. The sensitivity, specificity, and the NPV of CUS in detecting N2 disease were 14%, 98%, and 93%, respectively. Sensitivity and NPV were not significantly associated with age, sex, body mass index (BMI), tumour grade, lobar location, or histological type (P > 0.05). Minimal N2 disease was found in 37 of 43 patients with negative CUS results; only 6 of 596 patients had more than minimal (N2b) disease missed by CUS. The NPV for minimal N2 involvement was 98%.

CONCLUSION

In PET-negative mediastinal lymph nodes, N2 disease prevalence is low. CUS has an NPV of 93% for N2 disease and 98% for more than minimal N2 involvement. The diagnostic yield of CUS is unaffected by clinical characteristics, making it a reliable method for ruling out significant N2 disease in PET-negative patients and potentially reducing the need for more invasive procedures.

[18F]F-FAPI-42 PET dynamic imaging characteristics and multiparametric quantification of lung cancer: an exploratory study using uEXPLORER PET/CT

PURPOSE

To explore the dynamic and parametric characteristics of [18F]F-FAPI-42 PET/CT in lung cancers.

METHODS

Nineteen participants with newly diagnosed lung cancer underwent 60-min dynamic [18F]F-FAPI-42 PET/CT. Time-activity curves (TAC) were generated for tumors and normal organs, with kinetic parameters (K1, K2, K3, K4, Ki) calculated. A new parameter, the K ratio (K1 + K3)/(K2 + K4), was introduced to measure net uptake efficiency.

RESULTS

In primary tumor (PT), [18F]F-FAPI-42 uptake showed a gradual increase followed by a plateau, contrasting with organs like the thyroid and pancreas, which showed rapid uptake and continuous washout. Compared to non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC) lesions reached the plateau earlier (11 min vs. 14 min) but had a lower uptake. During the plateau phase, [18F]F-FAPI-42 demonstrated slight washout in SCLC, whereas its uptake increased slightly in NSCLC. Lymph node and distant metastases exhibited similar TAC profiles to primary tumors. Kinetic modeling revealed that an irreversible two-compartment model (irre-2TCM) best represented the pharmacokinetics of [18F]F-FAPI-42 in lung cancer, whereas re-2TCM was better suited for the pancreas and thyroid. Lower K1, K2, K3 and K4 were observed in PT compared to those in the pancreas and thyroid (P < 0.05), however, the K ratio in PT was found to be 2-3 times higher. SCLC had lower Ki and SUVmean than NSCLC (P < 0.05). Kinetic parameter differences were also observed between PT and metastatic lesions. Larger metastatic lymph nodes exhibited higher K1, Ki, and K ratio than smaller ones.

CONCLUSION

Lung cancers exhibit distinct [18F]F-FAPI-42 dynamic and kinetic characteristics compared to the thyroid gland and pancreas. Differences were also observed between SCLC and NSCLC, primary and metastatic lesions, as well as larger versus smaller lesions. These findings provide valuable insights into the in vivo pharmacokinetics of [18F]F-FAPI-42, potentially improving the diagnosis of lung cancer.

TRIAL REGISTRATION

ChiCTR2100045757. Registered April 24, 2021 retrospectively registered, http//www.chictr.org.cn.

FDG PET/CT for Staging Lung Carcinoma: An Update

In non-small cell lung carcinoma (NSCLC) carcinoma, the CT-part of the FDG PET/CT examination is of primary importance for T (tumor)-status assessment, while information derived from the primary tumor on the FDG-part of the examination may provide additional information on N- (lymph node) status. FDG PET/CT imaging was shown to have an overall sensitivity of 85% and a specificity of 84% for identifying LN involvement in NSCLC. Parameters that may predict the presence and quantify the risk of LN-involvement in NSCLC missed on FDG PET/CT imaging are tumor size and its increase over time, tumor differentiation degree, the number of days elapsed from the time of initial diagnosis, an adenocarcinoma subtype, a central versus peripheral location of the primary tumor and a solid versus mixed solid-ground glass radiologic character. Nomograms incorporating several of these variables have been published and made available for clinical usage. Furthermore, FDG PET/CT imaging was shown to have an overall higher sensitivity for identifying extra-thoracic metastases than convential morphological imaging and this especially for bone and adrenal lesions. In small cell lung carcinoma (SCLC), limited available data have shown FDG PET/CT imaging to be systematically more accurate for staging purposes when compared to conventional staging and to lead to a change in disease stage (limited versus extensive disease) in up to 15% of SCLC-patients.

18F-FDG PET/CT in the Preoperative Diagnostic and Staging of Lung Cancer and as a Predictor of Lymph Node Involvement

Background/Objectives: The aim of this study was to evaluate the efficacy and accuracy of PET imaging and performance in defining the preoperative TNM classification, especially the intrathoracic lymph node staging, of patients with lung cancer. Methods: A retrospective, single-institution study of consecutive patients with surgical therapy of lung cancer that were undergoing preoperative PET/CT scanning at the same center was conducted. A total of 104 patients were included. All patients underwent surgical evaluation with mediastinal and hilar lymph node sampling. Five patients with preoperative suspicion of N3 nodal status who were only tested for N2 were excluded from the observations and analyses of nodal status. Results: PET/CT staged the nodal status correctly in 85 out of 99 patients (85.9%); overstaging occurred in 7 patients (7.1%) and understaging in 7 patients (7.1%). The overall prevalence of lymph node metastases was 42.3%. When preoperative T classification was compared with postoperative histopathological T classification, 75% patients were correctly staged, 13.5% were overstaged, and 11.5% were understaged by PET/CT. In univariate analysis, lymph node involvement was significantly associated (p < 0.05) with the following primary tumor characteristics: increasing diameter (>35 mm), a maximum standardized uptake value > 9.5, and higher grading. The tumor diameter and the degree of differentiation were found to be factors influencing the SUVmax of the primary tumor as well. Conclusions: Our data show that integrated PET/CT provides high accuracy in the intrathoracic nodal staging and tumor expansion of lung cancer patients and emphasizes the continued need for surgical staging.

[18F]FDG PET/CT versus [18F]FDG PET/MRI in staging of non-small cell lung cancer: a head-to-head comparative meta-analysis

Purpose

This meta-analysis aims to compare the diagnostic efficacy of [18F]FDG PET/CT and [18F]FDG PET/MRI in patients with non-small cell lung cancer (NSCLC).

Methods

An extensive literature search was conducted throughout the PubMed, Embase, and Web of Science databases for works accessible through September 2024. We included studies assessed the diagnostic efficacy of [18F]FDG PET/CT and [18F]FDG PET/MRI in NSCLC.

Results

The meta-analysis includes six studies with a total of 437 patients. The sensitivity and specificity of [18F]FDG PET/CT and [18F]FDG PET/MRI for detecting lymph node metastasis were similar, at 0.82 (0.68-0.94) vs. 0.86 (0.70-0.97) and 0.88 (0.76-0.96) vs. 0.90 (0.85-0.94), respectively, with no significant differences (p = 0.70 for sensitivity, p = 0.75 for specificity). For distant metastasis, the sensitivity of [18F]FDG PET/CT and [18F]FDG PET/MRI was 0.86 (0.60-1.00) and 0.93 (0.63-1.00), and specificity was 0.89 (0.65-1.00) vs. 0.90 (0.64-1.00), respectively, also showing no significant differences (p = 0.66 for sensitivity, p = 0.97 for specificity).

Conclusion

Our meta-analysis shows that [18F]FDG PET/MRI has similar sensitivity and specificity to [18F]FDG PET/CT in identifying lymph node and distant metastases in patients with NSCLC. Additional larger sample prospective studies are needed to confirm these findings.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023479817, CRD42023479817.

Predicting lymph node metastasis of clinical T1 non-small cell lung cancer: a brief review of possible methodologies and controversies

Non-small cell lung cancer (NSCLC) is a major subtype of lung cancer and poses a serious threat to human health. Due to the advances in lung cancer screening, more and more clinical T1 NSCLC defined as a tumor with a maximum diameter of 3cm surrounded by lung tissue or visceral pleura have been detected and have achieved favorable treatment outcomes, greatly improving the prognosis of NSCLC patients. However, the preoperative lymph node staging and intraoperative lymph node dissection patterns of operable clinical T1 NSCLC are still subject to much disagreement, as well as the heterogeneity between primary tumors and metastatic lymph nodes poses a challenge in designing effective treatment strategies. This article comprehensively describes the clinical risk factors of clinical T1 NSCLC lymph node metastasis, and its invasive and non-invasive prediction, focusing on the genetic heterogeneity between the primary tumor and the metastatic lymph nodes, which is significant for a thoroughly understanding of the biological behavior of early-stage NSCLC.

Performing High-Quality Sublobar Resections: Key Differences Between Wedge Resection and Segmentectomy

Lung cancer remains the leading cause of cancer-related deaths worldwide. The introduction of targeted treatments and immunotherapy in lung cancer has transformed patient care by offering "precision medicine" focused on the characteristics of the disease. The same concept has emerged in lung cancer surgery. This "precision surgery" aims to determine the best surgical approach based on the characteristics of the cancer, the patient's cardiorespiratory status, and technological advances in thoracic surgery. While lobectomy continues to be the gold standard for managing early-stage lung cancer, the implementation of screening programs has enabled the earlier detection of smaller tumors. In this context, sublobar resections, particularly segmentectomy, have emerged as valuable options in the treatment of early-stage lung cancer. Recent studies suggest that sublobar resections, including segmentectomy and wedge resection, provide a viable alternative to lobectomy. This review explores the various resection strategies available, tailored to patient and tumor characteristics, and highlights modern preoperative techniques aimed at advancing precision surgery.

Comparative benefits of Ki and SUV images in lesion detection during PET/CT imaging

BACKGROUND

Clinical application of the tracer net influx rate (Ki) imaging in PET/CT remains limited, due to a lack of evidence demonstrating the superiority of Ki images in lesion detection, and guidelines on when to utilize Ki images. This study aims to compare the benefits of Ki and standardized uptake value (SUV) images in lesion detection during PET/CT imaging. By analyzing the performance of both techniques in identifying tumor lesions, the study seeks to provide guidance for the clinical application of Ki images.

RESULTS

This retrospective study included 134 patients with 244 pathologically confirmed lesions (200 malignant and 44 benign). Patients with a histopathological diagnosis received a weight-based 18F-FDG injection and underwent 60-min total-body PET/CT dynamic imaging. SUV images were reconstructed using data collected from the last 10 min of the scans. Ki images were generated using the Patlak methods with data from minutes 12-60. The background SUVmax, SUVmean, SUVSD, Kimax, Kimean, and KiSD values were recorded. The signal-to-noise ratios of the SUV (SUVSNR) and Ki (KiSNR) images were calculated. The lesion detection rate and sensitivity of the SUV and Ki images were evaluated. The lesion-detection rates were 97.7% (214/219) and 99.5% (218/219) for the SUV and Ki images, respectively (p = .22). Five false-negative lesions on the SUV images were true-positive on the Ki images (3 hepatic malignancies and 2 metastatic lymph nodes). The sensitivity (94.0% vs. 96.0%, p = .22), specificity (41.9% vs. 41.9%, p > .99), accuracy (84.4% vs. 86.1%, p = .61), positive predictive value (87.9% vs. 88.1%, p = .94), negative predictive value (60.0% vs. 69.2%, p = .47), and the area under the curve [0.68 (95% confidence interval, 0.61-0.73) vs. 0.69 (95% confidence interval, 0.62-0.74)] were similar in the SUV and Ki images (all p ≥ .10).

CONCLUSION

Ki images exhibit benefits in lesion detection compared to SUV images, particularly in organs with high background such as liver. The enhanced contrast provided by Ki imaging is recommended to clinically improve detection rates in such cases.

Invasive Nodal Staging via Endobronchial Ultrasound and Outcome in Patients Treated with Stereotactic Body Radiation Therapy for Early-Stage Non-Small Cell Lung Cancer - Results from a Single Institution Study

INTRODUCTION

Stereotactic body radiation therapy (SBRT) is an effective treatment for medically inoperable early-stage non-small cell lung cancer (NSCLC). The prognostic value of invasive nodal staging (INS) for patients undergoing SRBT has not been studied extensively. Herein, we report the impact of INS in addition to 18F-FDG-PET on treatment outcome for patients with NSCLC undergoing SBRT.

MATERIALS AND METHODS

Patients with stage I/ II NSCLC who underwent SBRT were included with IRB approval. Clinical, dosimetric, and radiological data were obtained. Overall survival (OS), regional recurrence free survival (RRFS), local recurrence free survival (LRFS), and distant recurrence free survival (DRFS) were analyzed using Kaplan Meyer method. Univariable analysis (UVA) and multivariable analysis (MVA) were performed to assess the relationship between the variables and the outcomes.

RESULTS

A total of 376 patients were included in the analysis. Median follow up was 43 months (IQ 32.6-45.8). Median OS, LRFS, RRFS, DRFS were 40, 32, 32, 33 months, respectively. The 5-year local, regional, and distant failure rates were 13.4%, 23.5% and 25.3%, respectively. The 1-year, 3-year and 5-year OS were 83.8%, 55.6%, and 36.3%, respectively. On MVA, INS was not a predictor of either improved overall or any recurrence free survival endpoints while larger tumor size, age, and adjusted Charleston co-morbidity index (aCCI) were significant for inferior LRFS, RRFS, and DRFS.

CONCLUSION

Invasive nodal staging did not improve overall or recurrence free survival among patients with early-stage NSCLC treated with SBRT whereas older age, aCCI, and larger tumor size were significant predictors of LRFS, RRFS, and DRFS.

Impact of preoperative [18F]FDG PET/CT vs. contrast-enhanced CT in the staging and survival of patients with clinical stage I and II non-small cell lung cancer: a 10-year follow-up study

OBJECTIVES

To elucidate the impact of [18F]FDG positron emission tomography/computed tomography (PET/CT) vs. CT workup on staging and prognostic evaluation of clinical stage (c) I-II NSCLC.

METHODS

We retrospectively identified 659 cI-II NSCLC who underwent CT (267 patients) or preoperative CT followed by PET/CT (392 patients), followed by curative-intended complete resection in our hospital from January 2008 to December 2013. Differences were assessed between preoperative and postoperative stage. Five-year disease-free survival (DFS) and overall survival (OS) rates were calculated using the Kaplan-Meier approach and compared with log-rank test. Impact of preoperative PET/CT on survival was assessed by Cox regression analysis.

RESULTS

The study included 659 patients [mean age, 59.5 years ± 10.8 (standard deviation); 379 men]. The PET/CT group was superior over CT group in DFS [12.6 vs. 6.9 years, HR 0.67 (95% CI 0.53-0.84), p < 0.001] and OS [13.9 vs. 10.5 years, HR 0.64 (95% CI 0.50-0.81), p < 0.001]. In CT group, more patients thought to have cN0 migrated to pN1/2 disease as compared with PET/CT group [26.4% (66/250) vs. 19.2% (67/349), p < 0.001], resulting in more stage cI cases being upstaged to pII-IV [24.7% (49/198) vs. 16.1% (47/292), p = 0.02], yet this was not found in cII NSCLC [27.5% (19/69) vs. 27.0% (27/100), p = 0.94]. Cox regression analysis identified preoperative PET/CT as an independent prognostic factor of OS and DFS (p = 0.002, HR = 0.69, 95% CI 0.54-0.88; p = 0.004, HR = 0.72, 95% CI 0.58-0.90).

CONCLUSION

Addition of preoperative [18F]FDG PET/CT was associated with superior DFS and OS in resectable cI-II NSCLC, which may result from accurate staging and stage-appropriate therapy.

Systematic mediastinal staging in non-small cell lung cancer: Filling in the guideline evidence gap

See related article

Computer-aided diagnosis of distal metastasis in non-small cell lung cancer by low-dose CT based radiomics and deep learning signatures

BACKGROUND

This study aimed to develop and validate radiomics and deep learning (DL) signatures for predicting distal metastasis (DM) of non-small cell lung cancer (NSCLC) in low-dose computed tomography (LDCT).

METHODS

Images and clinical data were retrospectively collected for 381 NSCLC patients and prospectively collected for 114 patients at the Fifth Affiliated Hospital of Sun Yat-Sen University. Additionally, we enrolled 179 patients from the Jiangmen Central Hospital to externally validate the signatures. Machine-learning algorithms were employed to develop radiomics signature while the DL signature was developed using neural architecture search. The diagnostic efficiency was primarily quantified with the area under receiver operating characteristic curve (AUC). We interpreted the reasoning process of the radiomics signature and DL signature by radiomics voxel mapping and attention weight tracking.

RESULTS

A total of 674 patients with pathologically-confirmed NSCLC were included from two institutions, with 143 of them having DM. The radiomics signature achieved AUCs of 0.885, 0.854, and 0.733 in the internal validation, prospective validation, and external validation while those for DL signature were 0.893, 0.786, and 0.780. The proposed signatures achieved a promising performance in predicting the DM of NSCLC and outperformed the approaches proposed in previous studies. Interpretability analysis revealed that both radiomics and DL signatures could detect the variations among voxels inside tumors, which helped in identifying the DM of NSCLC.

CONCLUSIONS

Our study demonstrates the potential of LDCT-based radiomics and DL signatures for predicting DM in NSCLC. These signatures could help improve lung cancer screening regarding further diagnostic tests and treatment strategies.

Comparison of the Outcomes between Systematic Lymph Node Dissection and Lobe-Specific Lymph Node Dissection for Stage I Non-small Cell Lung Cancer

BACKGROUND

This study compares the surgical and long-term outcomes, including disease-free survival (DFS), overall survival (OS), and cancer-specific survival (CSS), between lobe-specific lymph node dissection (L-SND) and systematic lymph node dissection (SND) among patients with stage I non-small cell lung cancer (NSCLC).

METHODS

In this retrospective study, 107 patients diagnosed with clinical stage I NSCLC undergoing video-assisted thoracic surgery lobectomy (exclusion of the right middle lobe) from January 2011 to December 2018 were enrolled. The patients were assigned to the L-SND (n = 28) and SND (n = 79) groups according to the procedure performed on them. Demographics, perioperative data, and surgical and long-term oncological outcomes were collected and compared between the L-SND and SND groups.

RESULTS

The mean follow-duration was 60.6 months. The demographic data and surgical outcomes and long-term oncological outcomes were not significantly different between the two groups. The 5-year OS of the L-SND and SND groups was 82% and 84%, respectively. The 5-year DFS of the L-SND and SND groups was 70% and 65%, respectively. The 5-year CSS of the L-SND and SND groups was 80% and 86%, respectively. All the surgical and long-term outcomes were not statistically different between the two groups.

CONCLUSION

L-SND showed comparable surgical and oncologic outcomes with SND for clinical stage I NSCLC. L-SND could be a treatment choice for stage I NSCLC.

Diagnosis and management of patients with stage III non‑small cell lung cancer: A joint statement by the Lebanese Society of Medical Oncology and the Lebanese Pulmonary Society (Review)

Proper management of stage III non-small cell lung cancer (NSCLC) might result in a cure or patient long-term survival. Management should therefore be preceded by adequate and accurate diagnosis and staging, which will inform therapeutic decisions. A panel of oncologists, surgeons and pulmonologists in Lebanon convened to establish a set of recommendations to guide and unify clinical practice, in alignment with international standards of care. Whilst chest computerized tomography (CT) scanning remains a cornerstone in the discovery of a lung lesion, a positron-emission tomography (PET)/CT scan and a tumor biopsy allows for staging of the cancer and defining the resectability of the tumor(s). A multidisciplinary discussion meeting is currently widely advised for evaluating patients on a case-by-case basis, and should include at least the treating oncologist, a thoracic surgeon, a radiation oncologist and a pulmonologist, in addition to physicians from other specialties as needed. The standard of care for unresectable stage III NSCLC is concurrent chemotherapy and radiation therapy, followed by consolidation therapy with durvalumab, which should be initiated within 42 days of the last radiation dose; for resectable tumors, neoadjuvant therapy followed by surgical resection is recommended. This joint statement is based on the expertise of the physician panel, available literature and evidence governing the treatment, management and follow-up of patients with stage III NSCLC.

Surgery versus radiotherapy in octogenarians with stage Ia non‑small cell lung cancer: propensity score matching analysis of the SEER database

Objectives

To compare overall survival (OS) and cancer-specific survival (CSS) outcomes of surgery with radiotherapy in octogenarians with stage Ia non-small cell lung cancer (NSCLC).

Materials and methods

Patients aged ≥ 80 years with clinical stage Ia (T1N0M0) NSCLC between 2012 and 2017 were identified from the population-based Surveillance, Epidemiology, and End Results (SEER) database. Patients were assigned into surgery and radiotherapy groups. Multivariate Cox regression analysis was used to identify survival-associated factors. Treatment groups were adjusted by propensity score matching (PSM) analysis while OS and CSS outcomes were compared among groups by Kaplan–Meier analysis.

Results

A total of 1641 patients were identified, with 46.0% in the surgical group and 54.0% in the radiotherapy group. Compared to surgery, radiotherapy-treated patients were older, later diagnosed, had more often unmarried, more squamous cell carcinoma, more unknown grade and increased tumor sizes. Radiotherapy was associated with a significantly worse OS, compared to surgery (hazard ratio 2.426; 95% CI 2.003–2.939; P < .001). After PSM, OS (P < 0.001) and CSS (P < 0.001) were higher in the surgery group. The 1-, 3-, and 5-year OS rates of surgical and radiotherapy group were 90.0%, 76.9%, 59.9%, and 86.0%, 54.3%, 28.0%, respectively. The 1-, 3-, and 5-year CSS rates of surgical and radiotherapy group were 94.5%, 86.1%, 78.0% and 90.7%, 74.5%, 61.0%, respectively. There were no survival differences between the matched surgery without lymph node examination (LNE) and radiotherapy group, as well as between the matched surgery and radiotherapy who were recommended but refused surgery group.

Conclusions

In octogenarians with stage Ia NSCLC, surgery with lymph node dissection offers better OS and CSS outcomes than radiotherapy.

Correlation analysis between unenhanced and enhanced CT radiomic features of lung cancers presenting as solid nodules and their efficacy for predicting hilar and mediastinal lymph node metastases

Objectives

If hilar and mediastinal lymph node metastases occur in solid nodule lung cancer is critical for tumor staging, which determines the treatment strategy and prognosis of patients. We aimed to develop an effective model to predict hilar and mediastinal lymph node metastases by using texture features of solid nodule lung cancer.

Methods

Two hundred eighteen patients with solid nodules on CT images were analyzed retrospectively. The 3D tumors were delineated using ITK-SNAP software. Radiomics features were extracted from unenhanced and enhanced CT images based on AK software. Correlations between radiomics features of unenhanced and enhanced CT images were analyzed with Spearman rank correlation analysis. According to pathological findings, the patients were divided into no lymph node metastasis group and lymph node metastasis group. All patients were randomly divided into training group and test group at a ratio of 7:3. Valuable features were selected. Multivariate logistic regression was used to build predictive models. Two predictive models were established with unenhanced and enhanced CT images. ROC analysis was used to estimate the predictive efficiency of the models.

Results

A total of 7 categories of features, including 107 features, were extracted. There was a high correlation between the 7 categories of features from unenhanced CT images and enhanced CT images (all r > 0.7, p < 0.05). Among them, the shape features had the strongest correlation (mean r = 0.98). There were 5 features in the enhanced model and the unenhanced model, which had important predicting significance. The AUCs were 0.811 and 0.803, respectively. There was no significant difference in the predictive performance of the two models (DeLong's test, p = 0.05).

Conclusion

Our study models achieved higher accuracy for predicting hilar and mediastinal lymph node metastasis of solid nodule lung cancer and have some value in promoting the staging accuracy of lung cancer. Our results show that CT radiomics features have potential to predict hilar and mediastinal lymph node metastases in solid nodular lung cancer. In addition, enhanced and unenhanced CT radiomics models had comparable predictive power in predicting hilar and mediastinal lymph node metastases.

Transesophageal Endoscopic Ultrasound Fine Needle Biopsy for the Diagnosis of Mediastinal Masses: A Retrospective Real-World Analysis

Background: Endoscopic ultrasound (EUS) plays an important role in the diagnosis and staging of thoracic disease. Our report studies the diagnostic performance and clinical impact of EUS fine needle aspiration (FNA) in a homogenous cohort of patients according to the distribution of the enlarged MLNs or pulmonary masses. Methods: We retrospectively reviewed the diagnostic performance of 211 EUS-FNA in 200 consecutive patients with enlarged or PET-positive MLNs and para-mediastinal masses who were referred to our oncological center between January 2019 and May 2020. Results: The overall sensitivity of EUS-FNA was 85% with a corresponding negative predictive value (NPV) of 56% and an accuracy of 87.5%. The sensitivity and accuracy in patients with abnormal MLNs were 81.1% and 84.4%, respectively. In those with para-mediastinal masses, sensitivity and accuracy were 96.4% and 96.8%. The accuracy for both masses and lymph nodes was 100%, and in the LAG (left adrenal gland), it was 66.6%. Conclusions: Our results show that, in patients with suspected mediastinal masses, EUS-FNA is an accurate technique to evaluate all reachable mediastinal nodal stations, including station 5.

Combination of 18F-FDG PET/CT and convex probe endobronchial ultrasound elastography for intrathoracic malignant and benign lymph nodes prediction

Background

Positron emission tomography–computed tomography (PET/CT) and convex probe endobronchial ultrasound (CP-EBUS) elastography are important diagnostic methods in predicting intrathoracic lymph nodes (LNs) metastasis, but a joint analysis of the two examinations is still lacking. This study aimed to compare the diagnostic efficiency of the two methods and explore whether the combination can improve the diagnostic efficiency in differentiating intrathoracic benign LNs from malignant LNs.

Materials and Methods

LNs examined by EBUS-guided transbronchial needle aspiration (EBUS-TBNA) and PET/CT from March 2018 to June 2019 in Shanghai Chest Hospital were retrospectively analyzed as the model group. Four PET/CT parameters, namely, maximal standardized uptake value mean standardized uptake value (SUVmean), SUVmean, metabolic tumor volume (MTV), and tumor lesion glycolysis (TLG); four quantitative elastography indicators (stiff area ratio, mean hue value, RGB, and mean gray value); and the elastography grading score of targeted LNs were analyzed. A prediction model was constructed subsequently and the dataset from July to November 2019 was used to validate the diagnostic capability of the model.

Results

A total of 154 LNs from 135 patients and 53 LNs from 47 patients were enrolled in the model and validation groups, respectively. Mean hue value and grading score were independent malignancy predictors of elastography, as well as SUVmax and TLG of PET/CT. In model and validation groups, the combination of PET/CT and elastography demonstrated sensitivity, specificity, positive and negative predictive values, and accuracy for malignant LNs diagnosis of 85.87%, 88.71%, 91.86%, 80.88%, and 87.01%, and 94.44%, 76.47%, 89.47%, 86.67%, and 88.68%, respectively. Moreover, elastography had better diagnostic accuracies than PET/CT in both model and validation groups (85.71% vs. 79.22%, 86.79% vs. 75.47%).

Conclusion

EBUS elastography demonstrated better efficiency than PET/CT and the combination of the two methods had the best diagnostic efficacy in differentiating intrathoracic benign from malignant LNs, which may be helpful for clinical application.

Mediastinal Staging with Endobronchial Ultrasound in Early-Stage Non-Small Cell Lung Cancer: Is It Necessary?

Herein we examine the need for minimally invasive mediastinal staging for patients with early-stage non-small cell lung cancer (NSCLC) using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Early NSCLC, stages 1 and 2, has a 5-year survival rate between 53 and 92%, whereas stages 3 and 4 have a 5-year survival of 36% and below. With more favorable outcomes in earlier stages, greater emphasis has been placed on identifying lung cancer earlier in its disease process. Accurate staging is crucial as it dictates both prognosis and therapy. Inaccurate staging can adversely impact surgical candidacy (if falsely "over-staged") or lead to inadequate treatment (if "under-staged"). Clinical staging utilizes noninvasive methods to evaluate the anatomic extent of disease; however, it remains controversial whether mediastinal staging of early NSCLC with radiological exams alone is sufficient. EBUS-TBNA has altered the landscape of invasive mediastinal staging and is a crucial component to improving confidence in lung cancer staging, specifically in early NSCLC. Radiographic occult lymph node metastasis identified upon review of surgical resection specimens of early NSCLC may support the argument to perform EBUS-TBNA in all cases of early-stage disease. Other data suggest that EBUS-TBNA could be spared in cases of peripheral cT1aN0 and cT1bN0 for which surgical resection with lymph node dissection is planned. By reviewing reported EBUS-TBNA outcomes in patients with early NSCLC, we aim to emphasize the necessity of staging with EBUS in this population.

Genomics Analysis and Nomogram Risk Prediction of Occult Lymph Node Metastasis in Non-Predominant Micropapillary Component of Lung Adenocarcinoma Measuring ≤ 3 cm

Background

The efficacy of sublobar resection and selective lymph node dissection is gradually being accepted by thoracic surgeons for patients within early-stage non-small cell lung cancer (NSCLC). Nevertheless, there are still some NSCLC patients develop lymphatic metastasis at clinical T1 stage. Lung adenocarcinoma with a micropapillary (MP) component poses a higher risk of lymph node metastasis and recurrence even when the MP component is not predominant. Our study aimed to explore the genetic features and occult lymph node metastasis (OLNM) risk factors in patients with a non-predominant micropapillary component (NP-MPC) in a large of patient’s cohort with surgically resected lung adenocarcinoma.

Methods

Between January 2019 and December 2021, 6418 patients who underwent complete resection for primary lung adenocarcinoma at the Qilu Hospital of Shandong University. In our study, 442 patients diagnosed with lung adenocarcinoma with NP-MPC with a tumor size ≤3 cm were included. Genetic alterations were analyzed using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Abnormal protein expression of gene mutations was validated using immunohistochemistry. A nomogram risk model based on clinicopathological parameters was developed to predict OLNM. This model was invalidated using the calibration plot and concordance index.

Results

In our retrospective cohort, the incidence rate of the micropapillary component was 11.17%, and OLNM was observed in 20.13% of the patients in our study. ARMS-PCR suggested that EGFR exon 19 del was the most frequent alteration in NP-MCP patients compared with other gene mutations (frequency: 21.2%, P<0.001). Patients harboring exon 19 del showed significantly higher risk of OLNM (P< 0.001). A nomogram was developed based on five risk parameters, which showed good calibration and reliable discrimination ability (C-index = 0.84) for evaluating OLNM risk.

Conclusions.

Intense expression of EGFR exon 19 del characterizes lung adenocarcinoma in patients with NP-MCP and it’s a potential risk factor for OLNM. We firstly established a nomogram based on age, CYFRA21-1 level, tumor size, micropapillary and solid composition, that was effective in predicting OLNM among NP-MCP of lung adenocarcinoma measuring ≤ 3 cm.

Rationale for Combing Stereotactic Body Radiation Therapy with Immune Checkpoint Inhibitors in Medically Inoperable Early-Stage Non-Small Cell Lung Cancer

Simple Summary

The rate of recurrence remains high for lymph node negative early-stage non-small cell lung cancer that are over 2–3 cm in size following stereotactic body radiation therapy (SBRT). This is due to the increased incidence of out-of-field failures, which warrants the addition of systemic therapy. Immune checkpoint inhibitors (ICIs), a class of immunotherapy, may induce a strong distant therapeutic effect known as the “abscopal” effect. This makes them a very suitable class of drugs to be combined with SBRT when treating early lung cancer with high-risk features, such as larger tumor size. In this review, we discuss the rationale and evidence for doing so.

Abstract

Stereotactic body radiation therapy (SBRT) has been widely adopted as an alternative to lobar resection in medically inoperable patients with lymph-node negative (N0) early-stage (ES) non-small cell lung cancer (NSCLC). Excellent in-field local control has been consistently achieved with SBRT in ES NSCLC ≤ 3 cm in size. However, the out-of-field control following SBRT remains suboptimal. The rate of recurrence, especially distant recurrence remains high for larger tumors. Additional systemic therapy is warranted in N0 ES NSCLC that is larger in size. Radiation has been shown to have immunomodulatory effects on cancer, which is most prominent with higher fractional doses. Strong synergistic effects are observed when immune checkpoint inhibitors (ICIs) are combined with radiation doses in SBRT’s dose range. Unlike chemotherapy, ICIs can potentiate a strong systemic response outside of the irradiated field when combined with SBRT. Together with their less toxic nature, ICIs represent a very suitable class of systemic agents to be combined with SBRT when treating ES NSCLC with high-risk features, such as larger tumor size. In this review, we describe the rationale and emerging evidence, as well as ongoing investigations in this area.

Definitions of Central Tumors in Radiologically Node-Negative, Early-Stage Lung Cancer for Preoperative Mediastinal Lymph Node Staging: A Dual-Institution, Multireader Study

BACKGROUND

Definitions for central lung cancer (CLC) have been ambiguous in guidelines, causing difficulty in selecting candidates for invasive mediastinal staging among patients with radiologically node-negative, early-stage lung cancer.

RESEARCH QUESTION

What is the optimal definition for CLC that is robust to interreader and institutional variation to select candidates for invasive mediastinal staging among those with clinical T1N0M0 lung cancer?

STUDY DESIGN AND METHODS

Two retrospective cohorts were evaluated for the associations of central lung cancer according to 13 definitions based on chest CT scan with occult nodal metastasis. Univariate and multivariate ordinal logistic regression analyses were performed with the pathologic N category as an ordinal outcome. Robust definitions, which retained statistical significance across multireader, dual-institutional datasets, were identified. For these definitions, binary diagnostic performance and interreader agreement were investigated.

RESULTS

In the two cohorts, 807 patients (median age, 63 years; interquartile range [IQR], 56-71 years; 410 women; 33 pN1, 48 pN2, and 1 pN3) and 510 patients (median age, 65 years; IQR, 58-71 years; 267 women; 33 pN1, 20 pN2, and no pN3) were included, respectively. Three definitions robust to interreader variation and dataset heterogeneity were identified: definition 7 (concentric lines arising from the midline, inner one-third, medial margin; adjusted OR, 2.01; 95% CI, 1.13-3.51; P = .02), definition 10 (location index-based inner one-third, center; adjusted OR, 3.60; 95% CI, 1.49-8.25; P = .003), and definition 12 (location index-based inner one-third, medial margin; adjusted OR, 3.57; 95% CI, 1.91-6.52; P < .001). Definition 12 showed higher interreader agreement than definition 7 (Cohen κ, 0.80 vs 0.66; P = .005). Nevertheless, the sensitivity and positive predictive value of the three definitions were < 50%.

INTERPRETATION

Three definitions exhibited robust associations with occult nodal metastasis. However, selecting candidates for invasive mediastinal staging solely based on a central tumor location would be suboptimal.

The expression of Nanog protein and fibroblast growth factor-inducible molecule 14 in patients with non-small cell lung cancer and their relationship with pathological characteristics and prognosis

Background

This study aimed to explore the expression of Nanog and fibroblast growth factor-inducible molecule 14 (Fn14) in patients with non-small cell lung cancer (NSCLC), and to explore their relationship with pathological characteristics and prognosis.

Methods

The clinical data of 89 patients with NSCLC admitted to this hospital from March 2015 to January 2019 were analyzed. The expression of Nanog and Fn14 in NSCLC tissues and normal tissues (5 cm around the tumor tissue) were analyzed by immunohistochemical staining. The relationship between Nanog and Fn14 expression and the patients’ pathological parameters was analyzed. Receiver operating characteristic curve (ROC) and Kaplan-Meier survival curves were drawn to analyze the influence of Nanog and Fn14 expression on prognosis, and logistic regression analysis was used to examine the related factors affecting the 2-year prognostic mortality of patients.

Results

The positive rates of Nanog and Fn14 in the observation group were significantly higher than those in the control group (P<0.05). The positive expression rates of Nanog and Fn14 were higher in patients with moderate/high differentiation, TNM stage III-IV, and lymph node metastasis (P<0.05). Among 89 patients with NSCLC, 25 patients died within 2 years of follow-up, with a survival rate of 71.91%. The mortality of patients with positive expression of Nanog and Fn14 was significantly higher than that of patients with negative expression (P<0.05). The median survival times of patients with negative and positive Nanog expression were (20.60±2.71) months and (18.03±2.11) months, respectively. The median survival times of patients with negative and positive Fn14 expression were (19.55±2.60) months and (15.65±2.14) months, respectively. The Kaplan-Meier survival curve showed that patients with both negative expression of Nanog and Fn14 had a longer survival time (P<0.05). Poor differentiation, TNM stage III-IV, lymph node metastasis, positive expression of Nanog, and positive expression of Fn14 were identified as risk factors affecting the prognostic mortality of patients with NSCLC (P<0.05).

Conclusions

Nanog and Fnl4 are closely related to the occurrence, development, and prognosis of NSCLC. Detection of their expression levels can provide reliable information for the early diagnosis of patients with NSCLC.

Clinicopathological and computed tomographic features associated with occult lymph node metastasis in patients with peripheral solid non-small cell lung cancer

OBJECTIVES

To investigate the value of combining clinicopathological characteristics with computed tomographic (CT) features of tumours for predicting occult lymph node metastasis (OLNM) in peripheral solid non-small cell lung cancer (PS-NSCLC).

METHODS

The study included 478 NSCLC clinically N0 (cN0) patients who underwent lobectomy and systemic lymph node dissection from January 2014 to August 2019. Patients were classified into OLNM and negative lymph node metastasis (NLNM) groups. The CT features of non-metastatic and metastatic lymph nodes with a largest short-diameter > 5 mm were compared in the OLNM group. Thereafter, the clinicopathological characteristics and CT morphological features of tumours were compared between both groups. Multivariable logistic regression analysis and receiver-operating characteristic curve were developed.

RESULTS

CT images detected 103 metastatic and 705 non-metastatic lymph nodes, and no significant differences in CT features of lymph nodes were found in all 161 OLNM patients (P > 0.05). For both groups, sex, carcinoembryonic antigen and pathological type differed significantly (all P < 0.05), while tumour size, necrosis, calcification, vascular convergence, pleural involvement, and the shortest interval of tumour-pleura differed significantly on CT images (all P < 0.05). Multivariable logistic regression analysis showed that carcinoembryonic antigen > 5.00 ng/ml, adenocarcinoma, absence of vascular convergence, and pleural involvement of Type II (one linear or cord-like pleural tag or tumour abut to the pleura with a broad base observed on both lung and mediastinal window images) were independent predicting factors of OLNM.

CONCLUSIONS

CT findings of lymph nodes can provide limited value and integrating clinicopathological characteristics with the CT morphological features of tumours is helpful in predicting OLNM in patients with PS-NSCLC.

FDG-PET/CT for pretherapeutic lymph node staging in non-small cell lung cancer: A tailored approach to the ESTS/ESMO guideline workflow

OBJECTIVES

In patients with NSCLC, current ESTS and ESMO guidelines recommend invasive lymph node (LN) staging with EBUS-TBNA even if FDG-PET/CT is negative for mediastinal LNs if at least one of three risk factors is present (cN1, non-peripheral primary or primary >3 cm). Modified workflows to avoid unnecessary invasive procedures were evaluated.

MATERIALS AND METHODS

Monocentric retrospective analysis of pretherapeutic FDG-PET/CT in 247 patients with NSCLC (62 % male; age, 68 [43-88] years) using an analog or digital PET/CT scanner. PET windowing was standardized. LNs were positive if 'LN uptake > mediastinal blood pool' or short axis >10 mm. Surgery or EBUS-TBNA served as reference for diagnostic accuracy per LN station. In all patients with negative mediastinal LNs by PET/CT, LN histology from surgery was available.

RESULTS

Among 700 L N stations analyzed, 180 were malignant. Sensitivity and specificity of PET/CT per LN station were 93 % and 71 %. Following current guidelines, 76 patients with mediastinal negative PET/CT required confirmatory invasive staging. Only 5/76 patients had unexpected pN2 (all had adenocarcinoma). In a modified approach, confirmatory invasive staging was confined to patients with mediastinal negative PET/CT who showed all three risk factors. Using this modification, EBUS-TBNA could have been omitted in 62 (82 %) of the 76 patients who required EBUS-TBNA based on current recommendation. Among these 62 patients, only one patient had unsuspected pN2 (single-level) while the remaining 61 of 62 omitted EBUS-TBNA were deemed unnecessary because mediastinal LNs were confirmed to be negative. No multi-level pN2 would have been missed.

CONCLUSION

In the current analysis, 82 % of EBUS-TBNA procedures in patients with mediastinal negative PET/CT could have been omitted by modifying the current guideline workflow as proposed (i.e., restricting EBUS-TBNA in patients with cN0/1 to those with all three risk factors). This was consistent with different PET/CT scanners. Prospective confirmation is required.

Utility of PET-CT in non-small cell lung cancer clinical stage IB-IIA according to AJCC 8th edition staging system: an alternative to invasive mediastinal staging?

Objective

Mediastinal nodal staging in lung cancer is essential to determine treatment strategy and prognosis. There are controversies as to whether a mediastinal negative result in PET-CT may spare the invasive staging of the mediastinum. The main endpoint is to evaluate the negative predictive value (NPV) of PET-CT in non-small cell lung cancer (NSCLC) clinical stage IB-IIA without clinical nodal involvement. The secondary endpoint is to evaluate the prevalence of mediastinal and hilar nodal affection in this population.

Methods

We performed an observational descriptive study from January 2010 to January 2020, including 76 patients with clinical stage IB-IIA, who underwent pulmonary resection with systematic nodal sampling (pre-determined lymph node stations based on tumour location) for primary NSCLC. Clinically, nodal involvement was defined as any lymph node greater than 1 cm in the short axis on a CT or with metabolic uptake greater than 2.5 SUV on PET-CT. The prevalence of nodal metastases was recorded.

Results

Fifty six patients had clinical stage IB and 20 had clinical stage IIA. Mean tumour size was 3.74 ± 0.5 cm. Lobectomy was the resection procedure most frequently performed. Of the 76 patients with clinical N0 by PET-CT who underwent surgical resection, 10 (13.1%) were upstaged to pN1 and none were upstaged to pN2. NPV of PET-CT for overall nodal metastasis was 87% (95% CI: 0.79-0.94). NPV of PET-CT for N2 metastasis was 100%.

Conclusion

PET-CT might be an alternative to invasive mediastinal staging in patients with NSCLC clinical stage IB-IIA who are surgical candidates. Further prospective multi-institutional studies are necessary to verify the external validity of our study.

How do we Classify a Central Tumor? Results of a Multidisciplinary Survey from the SEPAR Thoracic Oncology Area

INTRODUCTION

In patients with non-small cell lung cancer (NSCLC) and normal mediastinal imaging tests, centrally located tumors have greater occult mediastinal involvement. Clinical guidelines, therefore, recommend invasive mediastinal staging in this situation. However, definitions of centrality in the different guidelines are inconsistent. The SEPAR Thoracic Oncology area aimed to evaluate the degree of familiarity with various concepts related to tumor site among professionals who see patients with NSCLC in Spain.

METHODS

A questionnaire was distributed to members of Spanish medical societies involved in the management of NSCLC, structured according to the 3 aspects to be evaluated: 1) uniformity in the definition of central tumor location; 2) uniformity in the classification of lesions that extend beyond dividing lines; and 3) ability to delineate lesions in the absence of dividing lines.

RESULTS

A total of 430 participants responded. The most voted definition of centrality was «lesions in contact with hilar structures» (49.7%). The lines most often chosen to delimit the hemitorax were concentric hilar lines (89%). Most participants (92.8%) classified tumors according to the side of the dividing line that contained most of their volume. Overall, 78.6% were able to correctly classify a central lesion in the absence of dividing lines.

CONCLUSIONS

In our survey, the most widely accepted definition of centrality is not one of the proposals specified in the clinical guidelines. The results reflect wide variability in the classification of tumor lesions.

A propensity-matched analysis of stereotactic body radiotherapy and sublobar resection for stage I non-small cell lung cancer in patients at high risk for lobectomy: the results in a Chinese population

Background

To investigate the comparative effectiveness of stereotactic body radiotherapy (SBRT) and sublobar resection (SLR) in patients with stage I non-small cell lung cancer (NSCLC) considered to be high-risk lobectomy patients.

Methods

From January 2012 to December 2015, patients who underwent SBRT or SLR for clinical stage I NSCLC were examined retrospectively. Propensity score matching (PSM) was performed to reduce selection bias in SBRT and SLR patients.

Results

Data from 86 SBRT and 79 SLR patients was collected. Median follow-up periods of the SBRT and SLR groups were 32 and 37 months, respectively. Patients treated with SBRT exhibited significantly higher age, higher likelihood of being male, larger tumor diameter, lower forced expiratory volume in 1 second (FEV1), and poorer performance status compared with SLR patients. There were no significant differences between SBRT and SLR patients for 3-year overall survival (OS) (80.3% and 82.3%, P=0.405), cause-specific survival (CSS) (81.3% and 83.4%, P=0.383), and local control (LC) (89.7% and 86.0%, P=0.501). Forty-nine patients were identified from each group after performing PSM. After patients were matched for age, gender, performance status, tumor characteristics and pulmonary function, no significant differences were observed in 3-year OS (85.4% and 73.3%, P=0.649), CSS (87.2% and 74.9%, P=0.637) and LC (95.6% and 82.1%, P=0.055). Prevalence of significant adverse events (grade 3 or worse) was 0% and 10.2% in the matched SBRT and SLR groups (P=0.056), respectively.

Conclusions

Disease control and survival in the SBRT patients was equivalent to that seen in SLR patients with stage I NSCLC considered high-risk lobectomy candidates. SBRT could therefore be an alternative option to SLR in treating patients with a high operative risk.

The impact of pathologic staging of the hilar/mediastinal nodes on outcomes in patients with early-stage NSCLC receiving stereotactic body radiotherapy

Background

The importance of invasive mediastinal nodal staging in early-stage non-small cell lung cancer (NSCLC) in the PET/CT era is dependent on tumor factors that increase risk of nodal metastasis. At our institution, patients undergo biopsy via either CT-guidance (without nodal staging) or navigational bronchoscopy with endobronchial ultrasound transbronchial needle aspiration for nodal staging. This study aims to compare outcomes after stereotactic body radiotherapy (SBRT) stratified by receipt of invasive mediastinal nodal staging.

Methods

In this retrospective study, records of all consecutive patients undergoing SBRT for early-stage NSCLC between 2010 and 2017 were analyzed. The association between time-to event outcomes (recurrence and survival) were evaluated with covariates of interest including tumor size, location, histology, smoking history, prior lung cancer history, radiation dose and receipt of nodal staging. Both univariable and multivariable analyses were used to examine these comparisons.

Results

Overall, 158 patients were treated with SBRT. One hundred forty-nine out of one hundred fifty-eight patients (94%) underwent PET/CT staging, and all patients underwent tumor-directed biopsy. Seventy-nine patients underwent navigational bronchoscopy with nodal staging and 79 patients underwent CT-guided biopsy without nodal staging. Receipt of nodal staging was not associated with tumor size (P=0.35), yet was associated with central tumor location (P<0.001). There was no statistically significant association between receipt of nodal staging and time-to-event recurrence or survival outcomes; for example 3-year overall survival (OS) was 65% vs. 67% (P=0.65) and 3-year freedom from nodal failure was 84% vs. 69% (P=0.1) for those with and without nodal staging, respectively.

Conclusions

Similar recurrence and survival outcomes were observed after SBRT regardless of receipt of invasive mediastinal nodal staging. Further prospective evaluation can help identify which patients might derive greatest benefit from invasive staging of the mediastinum in the PET/CT era.

Central location and risk of imaging occult mediastinal lymph node involvement in cN0T2-4 non-small cell lung cancer

BACKGROUND

Appropriate pre-operative staging is a cornerstone in the treatment of non-small cell lung cancer (NSCLC). Central location and size greater than 3 cm are amongst indications for pre-operative invasive mediastinal staging but the quality of the evidence behind this recommendation is low.

METHODS

We retrospectively reviewed all cases of cT2-4N0M0 NSCLCL after CT and TEP-CT which underwent surgical resection with lymph node dissection or had a positive invasive pre-operative mediastinal staging in our institution from 2014 to 2018.

RESULTS

Three hundred and ten patients met inclusion criteria, 79 (25.5%) central and 231 (74.5%) peripheral tumors. Central tumor location was associated with a higher prevalence of pN2-3 disease (17.7% vs. 6.1%, P<0.001). In a multivariate analysis, central tumor location remained the only factor statistically associated with imaging occult mediastinal disease (OR 3.23, 95% CI: 1.45-7.18). NPV of PET-CT for occult mediastinal disease was 0.83 (95% CI: 0.72-0.90) in central and 0.94 (95% CI: 0.90-0.97) in peripheral tumor. Central location was also associated with a higher prevalence of occult N1 to N3 disease (43.0% vs. 15.2%, P<0.001).

CONCLUSIONS

This study suggests that invasive mediastinal staging is required in central cT2-4N0 NSCLC but can be questioned in peripheral one, especially in cT2N2 subgroup if the patient is a candidate for lobar resection.

Prognosis of segmentectomy in the treatment of stage IA non-small cell lung cancer

With improvements in detection technology, increasing numbers of patients with non-small cell lung cancer (NSCLC) are being diagnosed at an early stage. In order to treat the illness with minimal invasion and preserve lung function to the greatest possible extent, there has been an increasing tendency towards treating early-stage NSCLC by segmentectomy. However, questions remain regarding whether patients may benefit from this procedure considering the surgical and oncological outcomes. Whether adequate margin distance and lymph node dissection may be achieved is one of the most important issues associated with this procedure. The present study reviews the prognosis of segmentectomy in the treatment of stage IA NSCLC.

Impact of invasive nodal staging on regional and distant recurrence rates after SBRT for inoperable stage I NSCLC

PURPOSE/OBJECTIVES

Before definitive stereotactic body radiation therapy (SBRT) for presumably node-negative, early-stage NSCLC, many patients are staged with PET/CT alone. In patients undergoing PET/CT prior to SBRT, the role of invasive nodal staging (INS) with endobronchial ultrasound (EBUS) or mediastinoscopy is uncertain. We sought to characterize the impact of nodal staging modality on outcomes.

MATERIALS/METHODS

Patients receiving definitive SBRT for T1-2N0 NSCLC deemed node-negative by either PET/CT plus INS (EBUS or mediastinoscopy) or PET/CT alone were identified. Patients with initially equivocal or positive nodes on PET/CT were excluded from this analysis. All patients received 3-5 fraction SBRT according to institutional guidelines. Control was assessed by at least one follow-up CT in all patients. Multivariable logistic regression (MVA) was performed to identify variables independently associated with use of INS.

RESULTS

We identified 651 eligible patients at our institution from 2005-2016. INS was performed in 15.2% of patients (n = 99) with EBUS (n = 78) or mediastinoscopy (n = 21). Median follow-up was 19.4 months (0.2-135.1). Median survival was 28.5 months (0.6-140). Factors predictive of increased likelihood of INS after negative PET/CT on MVA were age (OR for decreasing age 1.033; 95% CI 1.058-1.010), Caucasian race (OR vs. non-white 1.852; 1.044-3.289), male sex (1.629; 1.031-2.575), central location (1.978; 1.218-3.211) and squamous histology (2.564; 1.243-5.287). Nodal and/or distant control at 2 years was similar between PET/CT alone (78%, 95% CI 74-82%) and INS + PET/CT (75%, 95% CI 65-85%) (p = 0.877) as well as on MVA. Overall survival did not differ based on staging modality.

CONCLUSIONS

In patients with early-stage NSCLC deemed node-negative by PET/CT, addition of INS did not appreciably alter patterns of failure or survival after definitive SBRT. This study does not question the established value of INS for equivocal or suspicious nodes.

Recent and Current Advances in FDG-PET Imaging within the Field of Clinical Oncology in NSCLC: A Review of the Literature

Lung cancer is the leading cause of cancer-related deaths around the world, the most common type of which is non-small-cell lung cancer (NSCLC). Computed tomography (CT) is required for patients with NSCLC, but often involves diagnostic issues and large intra- and interobserver variability. The anatomic data obtained using CT can be supplemented by the metabolic data obtained using fluorodeoxyglucose F 18 (FDG) positron emission tomography (PET); therefore, the use of FDG-PET/CT for staging NSCLC is recommended, as it provides more accuracy than either modality alone. Furthermore, FDG-PET/magnetic resonance imaging (MRI) provides useful information on metabolic activity and tumor cellularity, and has become increasingly popular. A number of studies have described FDG-PET/MRI as having a high diagnostic performance in NSCLC staging. Therefore, multidimensional functional imaging using FDG-PET/MRI is promising for evaluating the activity of the intratumoral environment. Radiomics is the quantitative extraction of imaging features from medical scans. The chief advantages of FDG-PET/CT radiomics are the ability to capture information beyond the capabilities of the human eye, non-invasiveness, the (virtually) real-time response, and full-field analysis of the lesion. This review summarizes the recent advances in FDG-PET imaging within the field of clinical oncology in NSCLC, with a focus on surgery and prognostication, and investigates the site-specific strengths and limitations of FDG-PET/CT. Overall, the goal of treatment for NSCLC is to provide the best opportunity for long-term survival; therefore, FDG-PET/CT is expected to play an increasingly important role in deciding the appropriate treatment for such patients.

Resectable IIIA-N2 Non-Small-Cell Lung Cancer (NSCLC): In Search for the Proper Treatment

Locally advanced non-small cell lung cancer accounts for one third of non-small cell lung cancer (NSCLC) at the time of initial diagnosis and presents with a wide range of clinical and pathological heterogeneity. To date, the combined multimodality approach involving both local and systemic control is the gold standard for these patients, since occult distant micrometastatic disease should always be suspected. With the rapid increase in treatment options, the need for an interdisciplinary discussion involving oncologists, surgeons, radiation oncologists and radiologists has become essential. Surgery should be recommended to patients with non-bulky, discrete, or single-level N2 involvement and be included in the multimodality treatment. Resectable stage IIIA patients have been the subject of a number of clinical trials and retrospective analysis, discussing the efficiency and survival benefits on patients treated with the available therapeutic approaches. However, most of them have some limitations due to their retrospective nature, lack of exact pretreatment staging, and the involvement of heterogeneous populations leading to the awareness that each patient should undergo a tailored therapy in light of the nature of his tumor, its extension and his performance status.

The impact of histology in the outcomes of patients with early-stage non-small cell lung cancer (NSCLC) treated with stereotactic body radiation therapy (SBRT) and adjuvant chemotherapy

INTRODUCTION

Stereotactic body radiation therapy (SBRT) is the standard of care treatment for nonsurgical patients with early-stage non-small cell lung cancer (NSCLC). A recent report has indicated an improvement in overall survival (OS) with adjuvant chemotherapy in patients with tumors ≥ 4 cm treated with SBRT. We present a retrospective study evaluating the impact of histology in patients treated with SBRT and adjuvant chemotherapy.

MATERIALS AND METHODS

Patients (≥18 years) diagnosed with clinical stages I-II NSCLC from 2004 to 2013 were identified using the National Cancer Database (n = 12,055). The Kaplan-Meier method was used to estimate overall survival (OS) distributions and the log-rank test was used to compare distributions by treatment strategy. Clinical stages I and II were subdivided according to the TNM staging and log-rank tests was used to compare survival distributions by treatment strategy within each subgroup. We performed subgroup analysis for the three main NSCLC histologies (i.e., adenocarcinoma, squamous cell carcinoma (SCC), and large cell).

RESULTS

In patients with adenocarcinoma, SCC and, large cell carcinoma; adjuvant chemotherapy was associated with worse OS in tumors < 4 cm (P<.0001, P<.0099, and P=.0082, respectively). In patients with adenocarcinoma and tumor ≥ 4 cm, adjuvant chemotherapy was not associated with improved OS (P=.262); however, in patients with SCC and large cell, adjuvant chemotherapy improved OS (P<.0001, and P=.0129, respectively).

CONCLUSION

In patients with NSCLC ≥ 4 cm treated with SBRT, adjuvant chemotherapy was associated with improved OS in patients with SCC and large cell histologies.

Evidence for Expanding Invasive Mediastinal Staging for Peripheral T1 Lung Tumors

BACKGROUND

Guidelines recommend invasive mediastinal staging for patients with non-small cell lung cancer and a "central" tumor. However, there is no consensus definition for central location. As such, the decision to perform invasive staging largely remains on an empirical foundation.

RESEARCH QUESTION

Should patients with peripheral T1 lung tumors undergo invasive mediastinal staging?

STUDY DESIGN AND METHODS

All participants with a screen-detected cancer with a solid component between 8 and 30 mm were identified from the National Lung Screening Trial. After translation of CT data, cancer location was identified and the X, Y, Z coordinates were determined as well as distance from the main carina. A multivariable logistic regression model was constructed to evaluate for predictors associated with lymph node metastasis.

RESULTS

Three hundred thirty-two participants were identified, of which 69 had lymph node involvement (20.8%). Of those with lymph node metastasis, 39.1% were N2. There was no difference in rate of lymph node metastasis based on tumor size (OR, 1.03; P = .248). There was also no statistical difference in rate of lymph node metastasis based on location, either by distance from the carina (OR, 0.99; P = .156) or tumor coordinates (X: P = .180; Y: P = .311; Z: P = .292). When adjusted for age, sex, histology, and smoking history, there was no change in the magnitude of the risk, and tests of significance were not altered.

INTERPRETATION

Our data indicate a high rate of N2 metastasis among T1 tumors and no significant relationship between tumor diameter or location. This suggests that patients with small, peripheral lung cancers may benefit from invasive mediastinal staging.

Lung cancer staging: State of the art in the era of ablative therapies and surgical segmentectomy

Implementation of lung cancer screening and improvements in imaging are expected to increase the proportion of lung cancer diagnosed at an early stage. The standard of care has historically been anatomic lobectomy; however, there is now an array of surgical and non-surgical approaches for management of local disease either in active use or under investigation. By their nature, these new modalities offer a theoretical trade-off of reduced morbidity in exchange for reduced efficacy in the setting of advanced disease. It is therefore critical that patients being considered for these approaches (e.g. surgical segmentectomy and SABR) be accurately staged to maximize the potential for definitive treatment. In this article, we will review current approaches to the staging of patients being considered for segmentectomy or ablation. This will serve as a foundation to highlight important questions deserving further investigation.

Invasive Staging Procedures Do Not Prevent Nodal Metastases From Being Missed in Stage I Lung Cancer

BACKGROUND

Up to 20% of clinical stage I lung cancer patients harbor lymph node metastases that go undetected (missed) during the clinical staging evaluation. We investigated to what degree the addition of invasive nodal staging procedures to imaging, as currently practiced, prevents radiographically occult nodal metastases from being missed during the clinical staging evaluation.

METHODS

Treatment-naive patients, imaged by positron emission tomography and computed tomography, who underwent lobectomy for clinical stage I lung cancer from 2012 to 2017 in The Society of Thoracic Surgeons General Thoracic Surgery Database were studied. Rates of missed nodal metastases (MNM) (ie, nodal metastases in lobectomy specimens undetected during clinical staging evaluation) were determined. Risk factors were assessed with multivariable modeling.

RESULTS

Of the 30,685 clinical stage I patients identified, 3895 (12.7%) underwent preoperative endobronchial ultrasound and 3341 (10.9%) underwent mediastinoscopy. Invasive staging was more common with tumors > 2 cm (66.4% vs 50.2%, P < .001) and squamous histology (26.9% vs 16.9%, P < .001). MNM were discovered in 14.7% of patients, including 20.1% of patients (95% confidence interval, 18.8%-21.5%) who had undergone endobronchial ultrasound and 18.2% (95% confidence interval, 16.7%-19.6%) who had undergone mediastinoscopy. Hilar nodes were most often "missed" (9.5%). Using cut-points in tumor size, histology, laterality, and age, patients could be stratified into particularly high-risk (25% MNM) and low-risk (6% MNM) cohorts.

CONCLUSIONS

Substantial risk of occult lymph node metastases persists in patients with clinical stage I lung cancer despite negative invasive nodal staging, positron emission tomography, and computed tomography. In the absence of a thorough surgical nodal evaluation, early-stage lung cancer patients are at risk of under-treatment.

Definitive Management of Presumed Synchronous Early Stage Non-Small Cell Lung Cancers: Outcomes and Utility of Stereotactic Ablative Radiation Therapy

PURPOSE

Management of synchronous early-stage non-small cell lung cancer (NSCLC) remains controversial because resection is not always feasible. This study evaluates efficacy and patterns of failure after SABR for synchronous early-stage NSCLC.

METHODS AND MATERIALS

From 2005 to 2015, patients presenting with ≥2 synchronous NSCLC tumors (T1a-T2b) and receiving SABR to ≥1 lesion were reviewed. The most common prescriptions were 50 Gy in 4 or 70 Gy in 10 fractions. Patients underwent multidisciplinary management with workup including chest computed tomography and positron emission tomography/computed tomography, plus brain imaging and endoscopic bronchial ultrasound for most patients to rule out mediastinal and distant disease. Synchronous lesions were defined as multiple ipsilateral or contralateral intrapulmonary lesions diagnosed within 6 months.

RESULTS

Of 912 patients treated with SABR for early-stage NSCLC at our institution, 82 (9%) presented with synchronous disease, with a total of 169 lesions. SABR was delivered to 142 lesions (84%), with 57 patients (69.5%) receiving SABR for all sites. Median overall survival (OS) and progression-free survival (PFS) were 5.1 and 2.7 years, respectively. At a median follow-up of 58 months, OS was 67% and 52% at 3 and 5 years, and corresponding PFS was 47% and 29%. Thirty-nine patients (48%) had progression, with 21 (26%) experiencing distant failure, and intralobar recurrence was among the first failure for 15 patients (18%). Of the 142 SABR-treated sites, these included 6 in-field (4%) and 4 marginal (3%) recurrences. There were no grade ≥3 adverse events. Among patients receiving SABR for all sites, there were no differences in OS (P = .946), PFS (P = .980), local control (P = .683), regional and distant control (P = .656), or toxicity (P = .791). On multivariable analysis, ipsilateral synchronous disease was associated with greater regional and distant failure (hazard ratio, 2.691; P = .025).

CONCLUSIONS

Synchronous NSCLC can be managed with definitive local therapy. With high control rates and favorable outcomes, SABR is an effective and feasible treatment for synchronous early-stage NSCLC.

FDG PET/CT in the Staging of Lung Cancer

BACKGROUND

Accurate staging is crucial for the proper management of patients with nonsmall cell lung cancer, especially for choosing the best treatment strategy. Different Imaging methods are used to stage patients with non-small cell lung cancer. In the last two decades, FDG PET/CT is carried out in almost all the main Hospitals around the world in this setting.

OBJECTIVE

The aim of this paper is to focus on the value of integrated FDG PET/CT in the TNM staging of the non-small cell lung cancer.

METHODS

A non-systematic revision of the literature was performed in order to identify all papers about the role of FDG PET/CT in the evaluation of non-small cell lung cancer and to highlight the value of FDG PET/CT in this setting.

RESULTS

Many data are now available about this topic, including also randomized controlled trials. FDG PET/CT is of limited added value in the characterization of T status but it increases the diagnostic accuracy for the assessment of the nodal status. The main advantage of FDG PET/CT over conventional imaging methods is its higher sensitivity in identifying extra-thoracic metastases, especially bone and adrenal lesions.

CONCLUSION

PET/CT with FDG should be included in the diagnostic work-up of patients with lung cancer, because it provides useful information for appropriate therapy.

Preoperative Risk Assessment of Lymph Node Metastasis in cT1 Lung Cancer: A Retrospective Study from Eastern China

Background

Lymph node status of clinical T1 (diameter ≤ 3 cm) lung cancer largely affects the treatment strategies in the clinic. In order to assess lymph node status before operation, we aim to develop a noninvasive predictive model using preoperative clinical information.

Methods

We retrospectively reviewed 924 patients (development group) and 380 patients (validation group) of clinical T1 lung cancer. Univariate analysis followed by polytomous logistic regression was performed to estimate different risk factors of lymph node metastasis between N1 and N2 diseases. A predictive model of N2 metastasis was established with dichotomous logistic regression, externally validated and compared with previous models.

Results

Consolidation size and clinical N stage based on CT were two common independent risk factors for both N1 and N2 metastases, with different odds ratios. For N2 metastasis, we identified five independent predictors by dichotomous logistic regression: peripheral location, larger consolidation size, lymph node enlargement on CT, no smoking history, and higher levels of serum CEA. The model showed good calibration and discrimination ability in the development data, with the reasonable Hosmer-Lemeshow test (p = 0.839) and the area under the ROC being 0.931 (95% CI: 0.906-0.955). When externally validated, the model showed a great negative predictive value of 97.6% and the AUC of our model was better than other models.

Conclusion

In this study, we analyzed risk factors for both N1 and N2 metastases and built a predictive model to evaluate possibilities of N2 metastasis of clinical T1 lung cancers before the surgery. Our model will help to select patients with low probability of N2 metastasis and assist in clinical decision to further management.

The utility of endosonography for mediastinal staging of non-small cell lung cancer in patients with radiological N0 disease

OBJECTIVES

Recent practice guidelines recommend endosonography for patients with radiological N0 non-small cell lung cancer (NSCLC) when the primary tumors are >3 cm in diameter or centrally located. However, any role for endosonography remains debatable. We evaluated the utility of endosonography in patients with radiological N0 NSCLC based on tumor centrality, diameter and histology.

MATERIALS AND METHODS

Patients who underwent staging endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) with or without transesophageal bronchoscopic ultrasound-guided fine needle aspiration (EUS-B-FNA) for radiological N0 NSCLC were retrospectively investigated using prospectively collected endosonography data. The radiological N0 stage was defined by node diameter as evident on computed tomography images and ¹⁸F-FDG uptake using integrated positron emission tomography-computed tomography.

RESULTS

In total of 168 patients, the median size of the primary tumor was 39 mm, and 41 % of tumors were centrally located. The prevalence of occult mediastinal metastases was 11.3 % (19/168). The sensitivity of endosonography in terms of diagnosing occult mediastinal metastases was only 47 % (9/19); 6 of 10 patients with false-negative endosonography data exhibited metastases in accessible nodes. The diagnostic performance of endosonography did not differ by tumor centrality or diameter. Patients with adenocarcinoma histology showed higher prevalence of occult mediastinal metastases and higher false-negative results in endosonography compared with those with non-adenocarcinoma histology.

CONCLUSION

Not all patients with radiological N0 NSCLC benefit from endosonography, given the low prevalence of occult mediastinal metastases and the poor sensitivity of endosonography in this population. The strategy of invasive mediastinal staging needs to be tailored considering the histology of the tumor in this population.

Role of FDG PET/CT in the Eighth Edition of TNM Staging of Non-Small Cell Lung Cancer

Lung cancer is the leading cause of cancer-related mortality in the United States, and accurate staging plays a vital role in determining prognosis and treatment. The recently revised eighth edition of the TNM staging system for lung cancer defines new T and M descriptors and updates stage groupings on the basis of substantial differences in survival. There are new T descriptors that are based on the findings at histopathologic examination, and T descriptors are reassigned on the basis of tumor size and extent. No changes were made to the N descriptors in the eighth edition of the TNM staging of lung cancer, because the four N categories that are based on the location of the diseased nodes can be used to consistently predict prognosis. The eighth edition includes a new M1b descriptor for patients with a single extrathoracic metastatic lesion in a single organ (M1b), because they have better survival and different treatment options, compared with those with multiple extrathoracic lesions (M1c). Examination with fluorine 18 fluorodeoxyglucose (FDG) PET/CT is the standard of care and is an integral part of the clinical staging of patients with lung cancer. To provide the treating physicians with accurate staging information, radiologists and nuclear medicine physicians should be aware of the updated classification system and should be cognizant of the site-specific strengths and limitations of FDG PET/CT. In this article, the eighth edition of the TNM staging system is reviewed, as well as the role of FDG PET/CT in the staging of non-small cell lung carcinoma. ^©RSNA, 2018.

Accuracy of positron emission tomography and computed tomography (PET/CT) in detecting nodal metastasis according to histology of non-small cell lung cancer

Positron emission tomography and computed tomography (PET-CT) is the non-invasive gold standard method for determining the oncological stage of patient with diagnosis of lung cancer. A correct preoperative staging is significant because only patients who do not have a history of regional or distant disease are those who will benefit from a surgical treatment. However, due to the different values of the PET-CT in terms of sensitivity and specificity to evaluate the mediastinal lymph node involvement, it is often necessary to perform a surgical mediastinal sampling through a cervical video mediastinoscopy (VM). Patient's risk factors which could modify the results of the PET scan, performing differences between non-invasive staging and the lymph node sampling due to VM are not yet clearly established in the literature. This knowledge will allow to identify in whom a surgical staging by sampling the mediastinal lymph nodes is needed. We included 234 patients with diagnosis of lung cancer who underwent a mediastinal lymph node staging by PET-CT images and histopathological results of mediastinal sampling by VM, analyzing the sensitivity and specificity of this non-invasive imaging study. We also analyzed variables that could modify the results of PET-CT, such as tumor type, location of the tumor and patient's history. We showed that those PET-CT presented an overall sensitivity and specificity of 93.8 and 62.7%, respectively, with negative and positive predictive values of 95.05 and 57.1%, respectively. The false-positive rate was 25% (57 of 234 patients). Analyzing risk factors involved in this false-positive rate (n = 57), we found that the only statistically significant factor that could explain these results was the histology of squamous carcinoma (p < 0.03). In this group of patients, it is essential to perform a mediastinal lymph node biopsy to know the real state of lymph node involvement.

Multidisciplinary consensus statement on the clinical management of patients with stage III non-small cell lung cancer

Stage III non-small cell lung cancer (NSCLC) is a very heterogeneous disease that encompasses patients with resected, potentially resectable and unresectable tumours. To improve the prognostic capacity of the TNM classification, it has been agreed to divide stage III into sub-stages IIIA, IIIB and IIIC that have very different 5-year survival rates (36, 26 and 13%, respectively). Currently, it is considered that both staging and optimal treatment of stage III NSCLC requires the joint work of a multidisciplinary team of expert physicians within the tumour committee. To improve the care of patients with stage III NSCLC, different scientific societies involved in the diagnosis and treatment of this disease have agreed to issue a series of recommendations that can contribute to homogenise the management of this disease, and ultimately to improve patient care.