Diagnostic value of fluorine 18 fluorodeoxyglucose positron emission tomography/computed tomography for the detection of metastases in non-small-cell lung cancer patients

CT-based intratumoral and peritumoral deep transfer learning features prediction of lymph node metastasis in non-small cell lung cancer

BACKGROUND

The main metastatic route for lung cancer is lymph node metastasis, and studies have shown that non-small cell lung cancer (NSCLC) has a high risk of lymph node infiltration.

OBJECTIVE

This study aimed to compare the performance of handcrafted radiomics (HR) features and deep transfer learning (DTL) features in Computed Tomography (CT) of intratumoral and peritumoral regions in predicting the metastatic status of NSCLC lymph nodes in different machine learning classifier models.

METHODS

We retrospectively collected data of 199 patients with pathologically confirmed NSCLC. All patients were divided into training (n = 159) and validation (n = 40) cohorts, respectively. The best HR and DTL features in the intratumoral and peritumoral regions were extracted and selected, respectively. Support Vector Machine (SVM), k-Nearest Neighbors (KNN), Light Gradient Boosting Machine (Light GBM), Multilayer Perceptron (MLP), and Logistic Regression (LR) models were constructed, and the performance of the models was evaluated.

RESULTS

Among the five models in the training and validation cohorts, the LR classifier model performed best in terms of HR and DTL features. The AUCs of the training cohort were 0.841 (95% CI: 0.776-0.907) and 0.955 (95% CI: 0.926-0.983), and the AUCs of the validation cohort were 0.812 (95% CI: 0.677-0.948) and 0.893 (95% CI: 0.795-0.991), respectively. The DTL signature was superior to the handcrafted radiomics signature.

CONCLUSIONS

Compared with the radiomics signature, the DTL signature constructed based on intratumoral and peritumoral areas in CT can better predict NSCLC lymph node metastasis.

Clinical management of stage III non-small cell lung cancer in India: An expert consensus statement

Non-small cell lung cancer (NSCLC) is considered the most common type of lung cancer (>80% of all lung cancers); patients are often diagnosed at advanced stages of the disease. The management of NSCLC is considered challenging owing to variations in size, an extension of the tumors, involvement patterns, and classification. Although adequate literature and guidelines are available on the management of NSCLC in several countries, an Indian perspective on stage III NSCLC management is lacking. We used the modified Delphi approach to form consensus statements. A thorough literature search was done. The authors then convened and deliberated over published literature, available guidelines, and clinical judgment. Recommendation statements were formed for different clinical scenarios. These statements were sent as a form of survey to other oncologists, and their responses were recorded and mentioned. Evidence-based statements were formed for diagnosing and managing stage III NSCLC. These recommendation statements cover various aspects-surgical, radiation, and medical treatment in various clinical scenarios including adjuvant, neoadjuvant, and consolidation therapies.

A comparison of 18 F-FDG PET-based radiomics and deep learning in predicting regional lymph node metastasis in patients with resectable lung adenocarcinoma: a cross-scanner and temporal validation study

OBJECTIVE

The performance of 18 F-FDG PET-based radiomics and deep learning in detecting pathological regional nodal metastasis (pN+) in resectable lung adenocarcinoma varies, and their use across different generations of PET machines has not been thoroughly investigated. We compared handcrafted radiomics and deep learning using different PET scanners to predict pN+ in resectable lung adenocarcinoma.

METHODS

We retrospectively analyzed pretreatment 18 F-FDG PET from 148 lung adenocarcinoma patients who underwent curative surgery. Patients were separated into analog (n = 131) and digital (n = 17) PET cohorts. Handcrafted radiomics and a ResNet-50 deep-learning model of the primary tumor were used to predict pN+ status. Models were trained in the analog PET cohort, and the digital PET cohort was used for cross-scanner validation.

RESULTS

In the analog PET cohort, entropy, a handcrafted radiomics, independently predicted pN+. However, the areas under the receiver-operating-characteristic curves (AUCs) and accuracy for entropy were only 0.676 and 62.6%, respectively. The ResNet-50 model demonstrated a better AUC and accuracy of 0.929 and 94.7%, respectively. In the digital PET validation cohort, the ResNet-50 model also demonstrated better AUC (0.871 versus 0.697) and accuracy (88.2% versus 64.7%) than entropy. The ResNet-50 model achieved comparable specificity to visual interpretation but with superior sensitivity (83.3% versus 66.7%) in the digital PET cohort.

CONCLUSION

Applying deep learning across different generations of PET scanners may be feasible and better predict pN+ than handcrafted radiomics. Deep learning may complement visual interpretation and facilitate tailored therapeutic strategies for resectable lung adenocarcinoma.

Lung Cancer Staging: Imaging and Potential Pitfalls

Lung cancer is the leading cause of cancer deaths in men and women in the United States. Accurate staging is needed to determine prognosis and devise effective treatment plans. The International Association for the Study of Lung Cancer (IASLC) has made multiple revisions to the tumor, node, metastasis (TNM) staging system used by the Union for International Cancer Control and the American Joint Committee on Cancer to stage lung cancer. The eighth edition of this staging system includes modifications to the T classification with cut points of 1 cm increments in tumor size, grouping of lung cancers associated with partial or complete lung atelectasis or pneumonitis, grouping of tumors with involvement of a main bronchus regardless of distance from the carina, and upstaging of diaphragmatic invasion to T4. The N classification describes the spread to regional lymph nodes and no changes were proposed for TNM-8. In the M classification, metastatic disease is divided into intra- versus extrathoracic metastasis, and single versus multiple metastases. In order to optimize patient outcomes, it is important to understand the nuances of the TNM staging system, the strengths and weaknesses of various imaging modalities used in lung cancer staging, and potential pitfalls in image interpretation.

Brain Metastasis Mimicking Glioma on Imaging Appearance During Tyrosine Kinase Inhibitor Administration: A Case Series and Literature Review

OBJECTIVE

Preoperative imaging diagnosis is critical to planning treatment strategies; however, it is occasionally challenging and sometimes misleading. The effects of molecularly targeted therapies on imaging appearances remain uncharted. We investigated the imaging characteristics of brain metastasis during tyrosine kinase inhibitor (TKI) administration.

METHODS

We analyzed the 12 cases of brain metastasis from lung cancer in our institute, including a case of a 49-year-old woman under gefitinib. Additionally, we reviewed the cases of brain metastasis from lung cancer with gefitinib treatment in the literature.

RESULTS

A woman during five-year gefitinib treatment for postoperative recurrence of lung adenocarcinoma was found to have a cerebellar tumoral lesion incidentally on magnetic resonance imaging (MRI). This lesion did not harbor any peritumoral edema, along with appearing hypometabolic on fluorodeoxyglucose (FDG) positron emission tomography (PET). This appearance was inconsistent with a typical metastatic appearance, and high-grade glioma was instead highly suspected, leading to a decision to proceed to gross total tumor resection. The pathological diagnosis, however, was brain metastasis from lung cancer. The other 11 cases without TKI treatment showed peritumoral edema on MRI and higher accumulation of FDG on PET. The two cases of brain metastasis with gefitinib in the literature showed no peritumoral edema on MRI.

CONCLUSION

TKIs like gefitinib can affect tumor biology, leading to a loss of typical imaging findings such as peritumoral brain edema and hyper-metabolism. As preoperative imaging diagnosis guides us in surgical planning, including biopsy or resection, ongoing treatment information should be fully integrated into imaging interpretation.

Radioisotope-Guided Excision of Mediastinal Lymph Nodes in Patients with Non-Small Cell Lung Carcinoma: Feasibility and Clinical Impact

BACKGROUND

Intraoperative localisation of nodal disease in non-small cell lung cancer (NSCLC) can be challenging. Lymph node localisation via radiopharmaceuticals is used in many conditions; we tested the feasibility of this approach in NSCLC.

METHODS

NSCLC patients were prospectively recruited. Intraoperative peri-tumoral injections of [99mTc]Tc-albumin nanocolloids were performed, followed by removing the tumour and locoregional lymph nodes. These were examined ex vivo with a gamma probe and labelled sentinel lymph nodes (SLNs) if they showed any activity or non-sentinel lymph nodes (nSLNs) if they did not. Thereafter, the surgical field was scanned with the probe; any further radioactive lymph node was removed and labelled as "extra" SLNs (eSLNs). All specimens were sent to histology, and metastatic status was recorded.

RESULTS

48 patients were enrolled, and 290 nodal stations were identified: 179 SLNs, 87 nSLNs, and 24 eSLNs. A total of 44 nodal metastases were identified in 22 patients, with 36 of them (82%) located within SLNs. Patients with nSLNs metastases had at least a co-existing positive SLN. No metastases were found in eSLNs.

CONCLUSIONS

The technique shows high sensitivity for intraoperative nodal metastases identification. This information could allow selective lymphadenectomies in low-risk patients or more aggressive approaches in high-risk patients.

State of the Art MR Imaging for Lung Cancer TNM Stage Evaluation

Since the Radiology Diagnostic Oncology Group (RDOG) report had been published in 1991, magnetic resonance (MR) imaging had limited clinical availability for thoracic malignancy, as well as pulmonary diseases. However, technical advancements in MR systems, such as sequence and reconstruction methods, and adjustments in the clinical protocol for gadolinium contrast media administration have provided fruitful results and validated the utility of MR imaging (MRI) for lung cancer evaluations. These techniques include: (1) contrast-enhanced MR angiography for T-factor evaluation, (2) short-time inversion recovery turbo spin-echo sequences as well as diffusion-weighted imaging (DWI) for N-factor assessment, and (3) whole-body MRI with and without DWI and with positron emission tomography fused with MRI for M-factor or TNM stage evaluation as well as for postoperative recurrence assessment of lung cancer or other thoracic tumors using 1.5 tesla (T) or 3T systems. According to these fruitful results, the Fleischner Society has changed its position to approve of MRI for lung or thoracic diseases. The purpose of this review is to analyze recent advances in lung MRI with a particular focus on lung cancer evaluation, clinical staging, and recurrence assessment evaluation.

Imaging of Lung Cancer Staging

Lung cancer is a leading cause of cancer-related mortality worldwide. Imaging is integral in accurate clinical staging to stratify patients into groups to predict survival and determine treatment. The eighth edition of the tumor, node, and metastasis (TNM-8) staging system proposed by the International Association for the Study of Lung Cancer in 2016, accepted by both the Union for International Cancer Control and the American Joint Committee on Cancer, is the current standard method of staging lung cancer. This single TNM staging is used for all histologic subtypes of lung cancer, including nonsmall cell lung cancer, small cell lung cancer, and bronchopulmonary carcinoid tumor, and it addresses both clinical and pathologic staging. Familiarity with the strengths and limitations of imaging modalities used in staging, the nuances of TNM-8, its correct nomenclature, and potential pitfalls are important to optimize patient care. In this article, we discuss the role of computed tomography (CT) and positron emission tomography/CT in lung cancer staging, as well as current imaging recommendations pertaining to TNM-8.

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.

Dynamic FDG-PET imaging for differentiating metastatic from non-metastatic lymph nodes of lung cancer

OBJECTIVES

18F-fluorodeoxyglucose (FDG) PET/CT has been widely used in tumor diagnosis, staging, and response evaluation. To determine an optimal therapeutic strategy for lung cancer patients, accurate staging is essential. Semi-quantitative standardized uptake value (SUV) is known to be affected by multiple factors and may fail to differentiate between benign and malignant lesions. Lymph nodes (LNs) in the mediastinal and pulmonary hilar regions with high FDG uptake due to granulomatous lesions such as tuberculosis, which has a high prevalence in China, pose a diagnostic challenge. This study aims to evaluate the diagnostic value of the quantitative metabolic parameters derived from dynamic 18F-FDG PET/CT in differentiating metastatic and non-metastatic LNs in lung cancer.

METHODS

One hundred and eight patients with pulmonary nodules were enrolled to perform 18F-FDG PET/CT dynamic + static imaging with informed consent. One hundred and thirty-five LNs in 29 lung cancer patients were confirmed by pathology. Static image analysis parameters including LN-SUVmax, LN-SUVmax/primary tumor SUVmax (LN-SUVmax/PT-SUVmax), mediastinal blood pool SUVmax (MBP-SUVmax), LN-SUVmax/MBP-SUVmax, and LN-SUVmax/short diameter. Quantitative parameters including K1, k2, k3 and Ki and of each LN were obtained by applying the irreversible two-tissue compartment model using in-house Matlab software. Ki/K1 was computed subsequently as a separate marker. We further divided the LNs into mediastinal LNs (N=82) and pulmonary hilar LNs (N=53). Wilcoxon rank-sum test or Independent-samples T-test and receiver-operating characteristic (ROC) analysis was performed on each parameter to compare the diagnostic efficacy in differentiating lymph node metastases from inflammatory uptake. P<0.05 were considered statistically significant.

RESULTS

Among the 135 FDG-avid LNs confirmed by pathology, 49 LNs were non-metastatic, and 86 LNs were metastatic. LN-SUVmax, MBP-SUVmax, LN-SUVmax/MBP-SUVmax, and LN-SUVmax/short diameter couldn't well differentiate metastatic from non-metastatic LNs (P>0.05). However, LN-SUVmax/PT-SUVmax have good performance in the differential diagnosis of non-metastatic and metastatic LNs (P=0.039). Dynamic metabolic parameters in addition to k3, the parameters including K1, k2, Ki, and Ki/K1, on the other hand, have good performance in the differential diagnosis of metastatic and non-metastatic LNs (P=0.045, P=0.001, P=0.001, P=0.001, respectively). For ROC analysis, the metabolic parameters Ki (AUC of 0.672 [0.579-0.765], sensitivity 0.395, specificity 0.918) and Ki/K1 (AUC of 0.673 [0.580-0.767], sensitivity 0.570, specificity 0.776) have good performance in the differential diagnosis of metastatic from non-metastatic LNs than SUVmax (AUC of 0.596 [0.498-0.696], sensitivity 0.826, specificity 0.388), included the mediastinal region and pulmonary hilar region.

CONCLUSION

Compared with SUVmax, quantitative parameters such as K1, k2, Ki and Ki/K1 showed promising results for differentiation of metastatic and non-metastatic LNs with high uptake. The Ki and Ki/K1 had a high differential diagnostic value both in the mediastinal region and pulmonary hilar region.

Comparison of 18 F-FDG PET/CT and 68 Ga-FAPI-04 PET/CT in patients with non-small cell lung cancer

AIM

In this study, we aimed to compare the diagnostic accuracy of 18 F-fluorodeoxyglucose ( 18 F-FDG) and Gallium-68 labeled fibroblast activator protein inhibitor ( 68 Ga-FAPI)-04 PET/CT in the tumor-node-metastasis (TNM) staging of patients with nonsmall cell lung cancer (NSCLC) and investigate whether adenocarcinoma (ADC) and squamous cell cancer (SCC) exhibit different uptake patterns on 68 Ga-FAPI-04 PET/CT.

MATERIALS AND METHOD

Twenty-nine patients with a histopathologically-confirmed diagnosis of NSCLC, who had no history of previous radiation therapy or chemotherapy and underwent 18 F-FDG PET/CT and 68 Ga-FAPI-04 PET/CT imaging between January 2021 and December 2021 were included in this retrospective study. Staging was performed using the 8th edition of the TNM staging system on both 18 F-FDG PET/CT and 68 Ga-FAPI-04 PET/CT images. Standardized uptake value (SUV) max and tumor-to-background ratios (TBR) were calculated on primary lesions and metastases.

RESULTS

There was no statistically significant difference in primary lesions in terms of SUV max and TBR values. However, 68 Ga-FAPI-04 PET/CT was significantly superior to 18 F-FDG PET/CT in terms of the number of lymph nodes and bone metastases revealed. The SUV max and TBR values of lymph nodes, hepatic lesions and bone lesions were significantly higher on 68 Ga-FAPI-04 PET/CT than on 18 F-FDG PET/CT. 68 Ga-FAPI-04 PET/CT changed the disease stage of three patients (10.9%). The diagnostic accuracy of 68 Ga-FAPI-04 PET/CT was 100%, whereas the diagnostic accuracy of 18 F-FDG PET/CT was 89.6% ( P  = 0.250).

CONCLUSION

Although 68 Ga-FAPI-04 PET/CT detected more lesions and higher diagnostic accuracy than 18 F-FDG PET/CT in NSCLC, neither method was statistically superior to each other in terms of diagnostic accuracy in TNM staging.

Machine learning classification of mediastinal lymph node metastasis in NSCLC: a multicentre study in a Western European patient population

BACKGROUND

[¹⁸F] FDG PET-CT has an important role in the initial staging of lung cancer; however, accurate differentiation between activity in malignant and benign intrathoracic lymph nodes on PET-CT scans can be challenging. The purpose of the current study was to investigate the effect of incorporating primary tumour data and clinical features to differentiate between [¹⁸F] FDG-avid malignant and benign intrathoracic lymph nodes.

METHODS

We retrospectively selected lung cancer patients who underwent PET-CT for initial staging in two centres in the Netherlands. The primary tumour and suspected lymph node metastases were annotated and cross-referenced with pathology results. Lymph nodes were classified as malignant or benign. From the image data, we extracted radiomic features and trained the classifier model using the extreme gradient boost (XGB) algorithm. Various scenarios were defined by selecting different combinations of data input and clinical features. Data from centre 1 were used for training and validation of the models using the XGB algorithm. To determine the performance of the model in a different hospital, the XGB model was tested using data from centre 2.

RESULTS

Adding primary tumour data resulted in a significant gain in the performance of the trained classifier model. Adding the clinical information about distant metastases did not lead to significant improvement. The performance of the model in the test set (centre 2) was slightly but statistically significantly lower than in the validation set (centre 1).

CONCLUSIONS

Using the XGB algorithm potentially leads to an improved model for the classification of intrathoracic lymph nodes. The inclusion of primary tumour data improved the performance of the model, while additional knowledge of distant metastases did not. In patients in whom metastases are limited to lymph nodes in the thorax, this may reduce costly and invasive procedures such as endobronchial ultrasound or mediastinoscopy procedures.

FDG PET/CT for Primary Staging of Lung Cancer and Mesothelioma

Lung cancer is the leading cause of cancer-related mortality in the United States. Accurate staging at initial diagnosis determines appropriate treatment and is the most important predictor of survival. Since 2018, the 8th edition of the TNM staging system has been used to stage lung cancer based on local tumor extent (T), nodal involvement (N), and metastases (M). 18 F fluorodeoxyglucose (FDG) PET/CT, which combines functional and anatomic imaging, is the standard of care and an integral part of clinical staging of patients with lung cancer. Malignant pleural mesothelioma (MPM), the most common primary malignant pleural tumor affecting the pleura is staged with 8th edition of TNM staging for MPM. 18 F FDG PET/CT is indicated in select patients who are surgical candidates to identify locally advanced tumor, nodal metastases, or extrathoracic metastases, which may preclude surgery.

[18F]FDG-PET/CT radiomics and artificial intelligence in lung cancer: Technical aspects and potential clinical applications

Lung cancer is the second most common cancer and the leading cause of cancer-related death worldwide. Molecular imaging using [¹⁸F]fluorodeoxyglucose Positron Emission Tomography and/or Computed Tomography ([¹⁸F]FDG-PET/CT) plays an essential role in the diagnosis, evaluation of response to treatment, and prediction of outcomes. The images are evaluated using qualitative and conventional quantitative indices. However, there is far more information embedded in the images, which can be extracted by sophisticated algorithms. Recently, the concept of uncovering and analyzing the invisible data extracted from medical images, called radiomics, is gaining more attention. Currently, [¹⁸F]FDG-PET/CT radiomics is growingly evaluated in lung cancer to discover if it enhances the diagnostic performance or implication of [¹⁸F]FDG-PET/CT in the management of lung cancer. In this review, we provide a short overview of the technical aspects, as they are discussed in different articles of this special issue. We mainly focus on the diagnostic performance of the [¹⁸F]FDG-PET/CT-based radiomics and the role of artificial intelligence in non-small cell lung cancer, impacting the early detection, staging, prediction of tumor subtypes, biomarkers, and patient's outcomes.

Toward Improved Outcomes for Patients With Lung Cancer Globally: The Essential Role of Radiology and Nuclear Medicine

PURPOSE

Key to achieving better population-based outcomes for patients with lung cancer is the improvement of medical imaging and nuclear medicine infrastructure globally. This paper aims to outline why and spark relevant health systems strengthening.

METHODS

The paper synthesizes the global lung cancer landscape, imaging referral guidelines (including resource-stratified ones), the reliance of TNM staging upon imaging, relevant multinational health technology assessments, and precisely how treatment selection and in turn patient outcomes hinge upon imaging findings. The final discussion presents data on current global gaps in both diagnostics (including imaging) and therapies and how, informed by such data, improved population-based outcomes are tangible through strategic planning.

RESULTS

Imaging findings are central to appropriate lung cancer patient management and can variably lead to life-prolonging interventions and/or to life-enhancing palliative measures. Early-stage lung cancer can be treated with curative intent but, unfortunately, most patients with lung cancer still present at advanced stages and many patients lack access to both diagnostics and therapies. Furthermore, half of lung cancer cases occur in low- and middle-income countries. The role of medical imaging and nuclear medicine in lung cancer management, as outlined herein, may help inform strategic planning.

CONCLUSION

Lung cancer is the number one cancer killer worldwide. The essential role that medical imaging and nuclear medicine play in early diagnosis and disease staging cannot be overstated, pivotal in selecting the many patients for whom measurably improved outcomes are attainable. Prevention synergized with patient-centered, compassionate, high-quality lung cancer management provision mandate that strategic population-based planning, including universal health coverage strategies, should extend well beyond the scope of disease prevention to include both curative and noncurative treatment options for the millions afflicted with lung cancer.

Value of 18F FDG-PET/CT parameters on long term follow-up for patients with non-small cell lung cancer

Objectives

The purpose of this study was to investigate the value of PET/CT in the preoperative staging of non-small cell lung cancer in predicting long-term survival and diagnostic performance, validated by histopathology following surgical resection.

Methods

Between 02/2009 and 08/2011, 255 patients with non-small cell lung cancer were included in this single-center prospective study. All underwent 18F FDG-PET/CT for pre-operative staging, and in 243 patients complete surgical resection was possible. Regarding lymph node involvement and extrathoracic metastases, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using the histopathological staging as reference. Median follow-up for censored patients was 9.1 years.

Results

Overall 5-year survival rate of all patients was 55.6%, and of patients who had complete surgical resection it was 58.2%. In multivariate analysis of all surgically resected patients lymph node involvement (p=0.029) and age >61 years (p=<0.001) were significant independent prognostic factors. SUVmax and SUVmean cut-offs between SUV 2 and 11, however, were not associated with better or ;worse survival. The PET-CT sensitivity, specificity, positive predictive value and negative predictive value for predicting lymph node involvement were 57, 95, 88, and 76%, respectively. Furthermore, sensitivity, specificity, positive predictive value, and negative predictive value for detecting extrathoracic metastases were 100, 58, 98, and 100%, respectively.

Conclusions

In this study, tumor 18F FDG-uptake values did not provide additional prognostic information. Age>61 years and lymph node metastasis were associated with worse long-term survival in surgically resected patients. 18F FDG-PET/CT scans allow for improved patient selection. However, in staging mediastinal lymph nodes, there is a high rate of false positives and false negatives, suggesting that tissue biopsy is still indicated in many cases.

Quantifying the rate and predictors of occult lymph node involvement in patients with clinically node-negative non-small cell lung cancer

PURPOSE

It is essential to evaluate the risk of occult lymph node (LN) disease in early-stage non-small cell lung cancer (NSCLC), especially because delivering stereotactic ablative radiotherapy (SABR) assumes no occult spread. This study was designed to assist clinicians in roughly quantifying this risk for cN0 NSCLC.

METHODS

The National Cancer Data Base was queried for cN0 cM0 lung squamous cell or adenocarcinoma who underwent surgery and LN dissection without neoadjuvant therapy. Statistics included multivariable logistic regression to evaluate factors associated with pN + disease.

RESULTS

109,964 patients were included. For tumors with size ≤1.0, 1.1-2.0, 2.1-3.0, 3.1-4.0, 4.1-5.0, 5.1-6.0, 6.1-7.0, and >7.0 cm, the pN + rate was 4.4, 7.7, 12.9, 18.0, 20.2, 22.5, 24.4, and 26.4%, respectively. When examining patients with more complete LN dissections (defined as removal of at least 10 LNs), the respective values were 6.6, 11.5, 17.6, 25.3, 26.8, 29.7, 30.7, and 31.6%. Moderately-poorly differentiated disease and adenocarcinomas were associated with a higher rate of pN + disease (p < .001 for both). For every cm increase in tumor size, the relative occult nodal risk increased by 10-14% (p < .001). For every elapsed day from initial diagnosis, the relative risk increased by ∼1% (p < .001). Graphs with best-fit lines were created based on tumor size, histology, and differentiation to aid physicians in estimating the pN + risk.

CONCLUSIONS

This nationwide study can allow clinicians to roughly estimate the rate of occult LN disease in cN0 NSCLC. These data can also assist in guiding enrollment on randomized trials of SABR ± immunotherapy, individualizing follow-up imaging surveillance, and patient counseling to avoid post-diagnosis delays.

Imaging of Oligometastatic Disease

Simple Summary

The imaging of oligometastatic disease (OMD) is challenging as it requires precise loco-regional staging and whole-body assessment. The combination of imaging modalities is often required. The more accurate imaging tool will be selected according to tumor type, the timing with regard to measurement and treatment, metastatic location, and the patient’s individual risk for metastasis. The most commonly used modalities are contrast-enhanced computed tomography (CT), magnetic resonance imaging and metabolic and receptor-specific imaging, particularly, ¹⁸F-fluorodesoxyglucose positron emission tomography/CT, used alone or in combination.

Abstract

Oligometastatic disease (OMD) is an emerging state of disease with limited metastatic tumor burden. It should be distinguished from polymetastatic disease due the potential curative therapeutic options of OMD. Imaging plays a pivotal role in the diagnosis and follow-up of patients with OMD. The imaging tools needed in the case of OMD will differ according to different parameters, which include primary tumor type, timing between measurement and treatment, potential metastatic location and the patient’s individual risk for metastasis. In this article, OMD is defined and the use of different imaging modalities in several oncologic situations are described in order to better understand OMD and its specific implication for radiologists.

Management of Early-Stage Resected Non-Small Cell Lung Cancer: Consensus Statement of the Lung cancer Consortium

BACKGROUND

Management of early-stage non-small cell lung cancer (ES-NSCLC) has evolved over the last few years especially in terms of work-up and the use of systemic therapy. This consensus statement was developed to present updated guidelines for the management of this disease.

METHODS

Multidisciplinary team (MDT) of lung cancer experts convened to discuss a set of pertinent questions with importance relevance to the management of ES-NSCLC. ES-NSCLC includes stages I, II and resected stage III. The experts included consultants in chest imaging, thoracic surgery, radiation oncology, and medical oncology. Questions were discussed in virtual meetings and then a written manuscript with supporting evidence was drafted, reviewed, and approved by the team members.

RESULTS

The Consensus Statement included 9 questions addressing work-up and management of ES-NSCLC. Background information and literature review were presented for each question followed by specific recommendations to address the questions by oncology providers. The Statement was endorsed by various oncology societies in the Gulf region.

CONCLUSION

The Consensus Statement serves as a guide for thoracic MDT members in the management of ES-NSCLC. Adaptation of these to the local setting is dictated usually by available resources and expertise, however, all efforts should be excreted to provide the optimal care to all patients whenever possible.

Management of Stage III Non-Small-Cell Lung Cancer: ASCO Guideline

PURPOSE

To provide evidence-based recommendations to practicing clinicians on management of patients with stage III non-small-cell lung cancer (NSCLC).

METHODS

An Expert Panel of medical oncology, thoracic surgery, radiation oncology, pulmonary oncology, community oncology, research methodology, and advocacy experts was convened to conduct a literature search, which included systematic reviews, meta-analyses, and randomized controlled trials published from 1990 through 2021. Outcomes of interest included survival, disease-free or recurrence-free survival, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 127 relevant studies to inform the evidence base for this guideline.

RECOMMENDATIONS

Evidence-based recommendations were developed to address evaluation and staging workup of patients with suspected stage III NSCLC, surgical management, neoadjuvant and adjuvant approaches, and management of patients with unresectable stage III NSCLC.Additional information is available at www.asco.org/thoracic-cancer-guidelines.

Bone Metastases Are Measurable: The Role of Whole-Body MRI and Positron Emission Tomography

Metastatic tumor deposits in bone marrow elicit differential bone responses that vary with the type of malignancy. This results in either sclerotic, lytic, or mixed bone lesions, which can change in morphology due to treatment effects and/or secondary bone remodeling. Hence, morphological imaging is regarded unsuitable for response assessment of bone metastases and in the current Response Evaluation Criteria In Solid Tumors 1.1 (RECIST1.1) guideline bone metastases are deemed unmeasurable. Nevertheless, the advent of functional and molecular imaging modalities such as whole-body magnetic resonance imaging (WB-MRI) and positron emission tomography (PET) has improved the ability for follow-up of bone metastases, regardless of their morphology. Both these modalities not only have improved sensitivity for visual detection of bone lesions, but also allow for objective measurements of bone lesion characteristics. WB-MRI provides a global assessment of skeletal metastases and for a one-step "all-organ" approach of metastatic disease. Novel MRI techniques include diffusion-weighted imaging (DWI) targeting highly cellular lesions, dynamic contrast-enhanced MRI (DCE-MRI) for quantitative assessment of bone lesion vascularization, and multiparametric MRI (mpMRI) combining anatomical and functional sequences. Recommendations for a homogenization of MRI image acquisitions and generalizable response criteria have been developed. For PET, many metabolic and molecular radiotracers are available, some targeting tumor characteristics not confined to cancer type (e.g. 18F-FDG) while other targeted radiotracers target specific molecular characteristics, such as prostate specific membrane antigen (PSMA) ligands for prostate cancer. Supporting data on quantitative PET analysis regarding repeatability, reproducibility, and harmonization of PET/CT system performance is available. Bone metastases detected on PET and MRI can be quantitatively assessed using validated methodologies, both on a whole-body and individual lesion basis. Both have the advantage of covering not only bone lesions but visceral and nodal lesions as well. Hybrid imaging, combining PET with MRI, may provide complementary parameters on the morphologic, functional, metabolic and molecular level of bone metastases in one examination. For clinical implementation of measuring bone metastases in response assessment using WB-MRI and PET, current RECIST1.1 guidelines need to be adapted. This review summarizes available data and insights into imaging of bone metastases using MRI and PET.

True abscopal effect in a patient with metastatic non-small cell lung cancer

Background

Systemic response to local anticancer treatment is a phenomenon called ‘abscopal effect’. The immune system is thought to play a pivotal role in its occurrence. To date, several cases have been reported, particularly in patients receiving combined local treatment and immune checkpoint inhibitors. In such cases, it is impossible to discriminate between the effects of local and systemic treatment. Only a few cases of abscopal effect have been described with radiotherapy alone.

Case presentation

Here, we report on the case of an 81-year-old woman with recurrent metastatic squamous cell carcinoma of the lung with mediastinal tumor bulk, lymph node and bone metastases. The patient refused to undergo systemic treatment, and palliative stereotactic radiotherapy of the mediastinal tumor was performed. At restaging with FDG-PET/CT, the patient presented with a decrease in size and FDG-avidity both of the irradiated site and of the lymph node and bone metastases (which did not receive radiotherapy). At 25 months after radiotherapy, the patient is still in remission at all sites.

Conclusions

This is a rare case of an abscopal effect after radiotherapy as monotherapy. It is one of the few hitherto reported for lung cancer. Several ongoing studies with a combination of radiotherapy and immunotherapy are seeking to exploit a potential synergy to induce abscopal effects.

An [18F]FDG-PET/CT deep learning method for fully automated detection of pathological mediastinal lymph nodes in lung cancer patients

Purpose

The identification of pathological mediastinal lymph nodes is an important step in the staging of lung cancer, with the presence of metastases significantly affecting survival rates. Nodes are currently identified by a physician, but this process is time-consuming and prone to errors. In this paper, we investigate the use of artificial intelligence–based methods to increase the accuracy and consistency of this process.

Methods

Whole-body ¹⁸F-labelled fluoro-2-deoxyglucose ([18F]FDG) positron emission tomography/computed tomography ([18F]FDG-PET/CT) scans (Philips Gemini TF) from 134 patients were retrospectively analysed. The thorax was automatically located, and then slices were fed into a U-Net to identify candidate regions. These regions were split into overlapping 3D cubes, which were individually predicted as positive or negative using a 3D CNN. From these predictions, pathological mediastinal nodes could be identified. A second cohort of 71 patients was then acquired from a different, newer scanner (GE Discovery MI), and the performance of the model on this dataset was tested with and without transfer learning.

Results

On the test set from the first scanner, our model achieved a sensitivity of 0.87 (95% confidence intervals [0.74, 0.94]) with 0.41 [0.22, 0.71] false positives/patient. This was comparable to the performance of an expert. Without transfer learning, on the test set from the second scanner, the corresponding results were 0.53 [0.35, 0.70] and 0.24 [0.10, 0.49], respectively. With transfer learning, these metrics were 0.88 [0.73, 0.97] and 0.69 [0.43, 1.04], respectively.

Conclusion

Model performance was comparable to that of an expert on data from the same scanner. With transfer learning, the model can be applied to data from a different scanner. To our knowledge it is the first study of its kind to go directly from whole-body [18F]FDG-PET/CT scans to pathological mediastinal lymph node localisation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05513-x.

Lung cancer

Lung cancer is one of the most frequently diagnosed cancers and the leading cause of cancer-related deaths worldwide with an estimated 2 million new cases and 1·76 million deaths per year. Substantial improvements in our understanding of disease biology, application of predictive biomarkers, and refinements in treatment have led to remarkable progress in the past two decades and transformed outcomes for many patients. This seminar provides an overview of advances in the screening, diagnosis, and treatment of non-small-cell lung cancer and small-cell lung cancer, with a particular focus on targeted therapies and immune checkpoint inhibitors.

The optimal timing of FDG-PET/CT in non-small cell lung cancer diagnosis and staging in an Australian centre

Background

Clinical practice guidelines and re-imbursement schedules vary in the recommended timing of FDG-PET/CT in the diagnostic evaluation of suspected or confirmed lung cancer. The aim was to estimate the probability of requiring more than one invasive test to complete diagnosis and staging in non-small cell lung cancer if FDG-PET/CT was used prior to initial biopsy (FDG-PET/CT First) compared to current Australian funding criteria (CT First).

Methods

Single-centre retrospective study of individuals with pathologically confirmed NSCLC without evidence of metastatic disease on baseline computed tomography (CT) of the chest. Decision tree analysis based on diagnosis and staging approaches estimated the probability of requiring more than one invasive biopsy. A Monte Carlo analysis with 1000 simulations was used to estimate decision tree precision.

Results

After exclusions, 115 patients were included with median (IQR) age of 71 (63–79) and 55.6% were male. The majority of cases were early stage (Stage I 43.5%, Stage II 19.1%) and adenocarcinoma (65.2%) histological subtype. The estimated probability of requiring more than one invasive biopsy with FDG-PET/CT prior was 0.12 compared to 0.19 when using the base case CT First scenario. Using the Monte Carlo analysis, the mean (95% CI) probability using the FDG-PET First approach was 0.15 (95%CI 0.12–0.20) versus 0.20 (95% CI 0.15–0.27) for the CT First approach. Only 7.8% had CT Chest-occult metastatic disease on FDG-PET that was accessible by percutaneous biopsy.

Conclusion

FDG-PET/CT performed prior to initial biopsy may reduce the proportion of people with NSCLC who require more than one biopsy attempt, but the clinical significance and overall cost-utility requires evaluation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01564-w.

Clinical validity of 25-gauge endobronchial ultrasound-guided transbronchial needle in lymph node staging of lung cancer

Background

Endobronchial ultrasound-guided transbronchial needle aspiration is recommended for lymph node (LN) staging in lung cancer. Although 22-gauge needles are widely used, they may make some stations difficult to puncture owing to an acute angle. A thinner 25-gauge needle was introduced in Japan at the end of 2016 and offered structural advantages such as improved flexibility and penetrability. We aimed to validate the clinical utility of the 25-gauge needle in LN staging.

Methods

Patients who underwent endobronchial ultrasound-guided transbronchial needle aspiration for LN staging of lung cancer using the 25-gauge needle at our institution between November 2016 and March 2019 were included. Patient characteristics, staging procedures, pathology findings, and genetic testing success rates were assessed.

Results

Data of 130 patients were included in the analysis. The sampling rate was 87.6% (589/672 lesions). In addition to stations #4R, #7, and #11, which are generally easy to puncture, multiple stations (40.1%) were sampled. The diagnostic accuracy of combined computed tomography and fluorodeoxyglucose positron emission tomography was 82.3% and that of additional endobronchial ultrasound-guided transbronchial needle aspiration was 96.9%. The overall sensitivity, specificity, and positive and negative predictive values validated using resected specimens were 97.1% (34/35), 100% (41/41), 100% (34/34), and 97.6% (41/42), respectively. The success rate of genetic testing was 100% (34/34).

Conclusions

The new 25-gauge needle enabled us to approach a wide range of LNs with a desirable sampling rate and diagnostic accuracy in LN staging using endobronchial ultrasound-guided transbronchial needle aspiration, while providing enough tissue for genetic testing.

Improving accuracy of 18F-fluorodeoxyglucose PET computed tomography to diagnose nodal involvement in non-small cell lung cancer: utility of using various predictive models

PURPOSE

To determine predictive models (PM) that could improve the accuracy for identifying metastatic regional nodes in non-small cell lung cancer based on both PET and CT findings seen on 18F-FDG PET CT.

METHODS

Three hundred thirty-nine biopsy-proven NSCLC patients who underwent surgical resection and had a staging 18F-FDG PET CT were enrolled. PET parameters obtained were (1) presence of visual PET positive nodes, (2) SUVmax of nodes (NSUV), (3) ratio of node to aorta SUVmax (N/A ratio) and (4) ratio of node to primary tumour SUVmax (N/T ratio). CT parameters obtained were (1) short-axis diameter and (2) Hounsfield units (HU) of PET-positive nodes. PET and CT parameters were correlated with nodal histopathology to find out the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy. Different PM combining these parameters were devised and the incremental improvement in accuracy was determined.

RESULTS

Visual PET positivity showed sensitivity, specificity, PPV, NPV and accuracy of 72.4, 76.1, 30.1, 95.1 and 75.6, respectively. PM2 which combined visual PET positivity, NSUV and HU appears more clinically relevant and showed sensitivity, specificity, PPV, NPV and accuracy of 53.5, 96.5, 68.9, 93.6 and 91.2, respectively. PM6 which combined visual PET positivity, NSUV, N/A ratio and HU showed the maximum PPV (80.0%), specificity (98.3%) and accuracy of (91.9%).

CONCLUSION

PM combining parameters like nodal SUVmax, N/A ratio, N/T ratio and HU values have shown to improve the PPV, specificity and overall accuracy of 18FDG PET CT in the preoperative diagnosis of nodal metastases.

MRI-based differentiation between lymphoma and sarcoidosis in mediastinal lymph nodes

OBJECTIVE

Evaluation of enlarged mediastinal lymph nodes is crucial for patient management. Malignant lymphoma and sarcoidosis are often difficult to differentiate. Our objective was to determine the diagnostic accuracy of MRI for differentiating between sarcoidosis and malignant lymphoma.

METHODS

This was a retrospective study involving 47 patients who underwent chest MRI and were diagnosed with one of the diseases between 2017 and 2019. T1, T2, and diffusion-weighted signal intensity were measured. Apparent diffusion coefficients (ADCs) and T2 ratios were calculated. The diagnostic performance of MRI was determined by ROC analysis.

RESULTS

Mean T2 ratio was significantly lower in the sarcoidosis group than in the lymphoma group (p = 0.009). The T2-ratio cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 7.1, with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 58.3%, 95.6%, 76.5%, 93.3%, and 68.7%, respectively. The mean ADC was significantly lower in the lymphoma group than in the sarcoidosis group (p = 0.002). The ADC cutoff value that best differentiated between lymphoma-related and sarcoidosis-related enlarged lymph nodes was 1.205, with a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 87.5%, 82.6%, 85.1%, 84.0% and 86.3%, respectively. No significant differences were found between the two groups regarding T1 signal intensity, T2 signal intensity, and lymph node diameter.

CONCLUSIONS

MRI parameters such as ADC, diffusion, and T2 ratio can be useful in the differentiation between sarcoidosis and lymphoma in the evaluation of enlarged lymph nodes.

The Significance of Skip Mediastinal Lymph Node Metastasis in the Prognosis of Patients with Resected Non-Small-Cell Lung Carcinoma: Is It Really a Better N2 Disease Subtype?

Objective: In this study, we aimed to reveal the prognostic differences between skip and non-skip metastasis mediastinal lymph node (MLN) metastasis.

Methods: A total of 202 patients (179 males and 23 females; mean age, 59.66 ± 9.89 years; range: 29–84 years) who had ipsilateral single-station MLN metastasis were analyzed in two groups retrospectively between January 2009 and December 2017: “skip ipsilateral MLN metastasis” group (sN2) (n = 55,27.3%) [N1(–), N2(+)], “non-skip ipsilateral MLN metastasis” group (nsN2) (n = 147,72.7%) [N1(+), N2(+)].

Results: The mean follow-up was 42.63 ± 34.91 months (range: 2–117 months). Among all patients, and in the sN2 and nsN2 groups, the median overall survival times were 63.5 ± 4.56, 68.8 ± 7, and 59.3 ± 5.35 months, respectively, and the 5-year overall survival rates were 38.2%, 46.3%, and 36.4%.

Conclusion: Skip metastasis did not take its rightful place in TNM classification; thus, further studies will be performed. To detect micrometastasis, future studies on skip metastasis should examine non-metastatic hilar lymph nodes (LNs) through staining methods so that heterogeneity in patient groups can be avoided, that is, to ensure that only true skip metastasis cases are included. Afterwards, more accurate and elucidative studies on skip metastasis can be achieved to propound its prognostic importance in the group of N2 disease.

Impact of 18F-FDG PET/CT, CT and EBUS/TBNA on preoperative mediastinal nodal staging of NSCLC

BACKGROUND

Staging of non-small-cell lung cancer (NSCLC) is a multidisciplinary process involving imaging, endoscopic and surgical techniques. This study aims at investigating the diagnostic accuracy of ¹⁸F-FDG PET/CT, CT scan, and endobronchial ultrasound/transbronchial needle aspirate (EBUS/TBNA) in preoperative mediastinal lymph nodes (MLNs) staging of NSCLC.

METHODS

We identified all patients who were diagnosed with NSCLC at the King Hussein Cancer Center in Amman, Jordan, between July 2011 and December 2017. We collected their relevant clinical, radiological, and histopathological findings. The per-patient analysis was performed on all patients (N = 101) and then on those with histopathological confirmation (N = 57), followed by a per-lymph-node-station basis overall, and then according to distinct N-stage categories.

RESULTS

¹⁸F-FDG PET/CT, in comparison to CT, had a better sensitivity (90.5% vs. 75%, p = 0.04) overall and in patients with histopathological confirmation (83.3% vs. 54.6%), and better specificity (60.5% vs. 43.6%, p = 0.01) overall and in patients with histopathological confirmation in MLN staging (60.6% vs. 38.2%). Negative predictive value of mediastinoscopy, EBUS/TBNA, and ¹⁸F-FDG PET/CT were (87.1%), (90.91%), and (83.33%) respectively. The overall accuracy was highest for mediastinoscopy (88.6%) and EBUS/TBNA (88.2%), followed by ¹⁸F-FDG PET/CT (70.2%). Dividing patients into N1 disease vs. those with N2/N3 disease yielded similar findings. Comparison between ¹⁸F-FDG PET/CT and EBUS/TBNA in patients with histopathological confirmation shows 28 correlated true positive and true negative findings with final N-staging. In four patients, ¹⁸F-FDG PET/CT detected metastatic MLNs that would have otherwise remained undiscovered by EBUS/TBNA alone. Lymph nodes with a maximal standardized uptake value (SUVmax) more than 3 were significantly more likely to be true-positive.

CONCLUSION

Multimodality staging of the MLNs in NSCLC is essential to provide accurate staging and the appropriate treatment. ¹⁸F-FDG PET/CT has better overall diagnostic utility when compared to the CT scan. The NPV of ¹⁸F-FDG PET/CT in MLNs is reliable and comparable to the NPV of EBUS/TBNA. SUVmax of MLNs can help in predicting metastases, but nevertheless, a positive ¹⁸F-FDG PET/CT MLNs particularly if such a result would change the treatment plan, should be verified histopathologically.

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.

Correlation study between flash dual source CT perfusion imaging and regional lymph node metastasis of non-small cell lung cancer

Background

To explore the correlation of flash dual source computed tomography perfusion imaging (CTPI) and regional lymph node metastasis of non-small cell lung cancer (NSCLC), and to evaluate the value of CT perfusion parameters in predicting regional lymph node metastasis of NSCLC.

Methods

120 consecutive patients with NSCLC confirmed by postoperative histopathology were underwent flash dual source CT perfusion imaging in pre-operation. The CT perfusion parameters of NSCLC, such as blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability (PMB) were obtained by the image post-processing. Then microvessel density (MVD), luminal vascular number (LVN), luminal vascular area (LVA) and luminal vascular perimeter (LVP) of NSCLC were counted by immunohistochemistry. These cases were divided into group A (patients with lymph node metastasis, 58 cases) and group B (patients without lymph node metastasis, 62 cases) according to their pathological results. The CT perfusion parameters and the microvessel parameters were contrastively analysed between the two groups. Receiver operating characteristic (ROC) curve was used to assess the diagnostic efficiency of CT perfusion parameters in predicting regional lymph node metastasis of NSCLC in pre-operation.

Results

Group A presented significantly lower LVA, BF and higher MTT, PMB than Group B (P < 0.05), while BV, LVN, LVP and MVD were no significant difference (P > 0.05). Correlation analysis showed that BF was correlated with LVA and LVP (P < 0.05), while BV, MTT and PMB were not correlated with LVN, LVA and LVP (P > 0.05). All the perfusion parameters were not correlated with MVD. According to the ROC curve analysis, when BF < 85.16 ml/100 ml/min as a cutoff point to predict regional lymph node metastasis of NSCLC, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 60.8, 81.7, 71.5, 75.6 and 69.5% respectively.

Conclusion

Flash dual source CT perfusion imaging can non-invasively indicate the luminal vascular structure of tumor and BF can be used as one of the important indexes in predicting regional lymph node metastasis of NSCLC in pre-operation.

The added value of18F-FDG PET/CT in staging non-small cell lung cancer

Background

Non-small cell lung cancer (NSCLC) accounts for about 80% of all lung cancers. The current criteria for its staging are based on the TNM system that determines treatment options and predicts survival rate in patients. The aim of the study was to evaluate the diagnostic accuracy of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography PET/CT in staging of NSCLC patients.

Methods

A retrospective study was conducted. We reviewed the CT and PET/CT examinations done in our institution on pathologically proven patients of NSCLC, in the period between October 2018 and end of July 2019.

Results

A total of 40 patients were evaluated with the age ranging from 37 to 77 years old, and the mean was 55.63 years (SD ± 10.29). There were 31 male cases and 9 female cases. When we compared contrast enhanced CT (CECT) to PET-CT for staging, PET-CT helped upstage disease in 10 of 40 patients (25%) and downstage in 3 of 40 patients (7.5%).

Conclusion

PET/CT is a useful imaging tool in initial staging of the newly diagnosed patients with NSCLC. It is better thаn СT alone fоr detection of malignant lesions for accurate staging. It can change the strategy of treatment according to its findings.

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.

Multidisciplinary expert opinion on the treatment consensus for patients with EGFR mutated NSCLC with brain metastases

The presence of an epidermal growth factor receptor (EGFR) mutation is associated with higher incidence of brain metastases in patients with non-small cell lung cancer (NSCLC); however, patients with synchronous brain metastases at diagnosis have generally been excluded from clinical trials. As there is limited clinical evidence for managing this patient population, a multidisciplinary group of Spanish medical and radiation oncologists, and neuro-oncologist with expertise treating brain metastases in lung cancer patients met with the aim of reaching and developing an expert opinion consensus on the management of patients with EGFR mutated NSCLC with brain metastases. This consensus contains 26 recommendations and 20 conclusion statements across 21 questions in 7 areas, as well as a first-line treatment algorithm.

Fluorine-18-fluorodeoxyglucose-positron emission tomography evaluation in metastatic bone lesions in lung cancer: Possible prediction of pain and skeletal-related events

Background

Fluorine‐18‐fluorodeoxyglucose‐positron emission tomography (FDG‐PET) uptake in primary lesions has been well studied, but little information is available about metastatic bone lesions in patients with lung cancer. The present study was performed to evaluate the relationships between metastatic bone FDG uptake and clinical parameters in patients with lung cancer.

Methods

FDG uptake was evaluated as the maximum standardized uptake (SUVmax) value of each targeted bone lesion, and the bone to primary lesion ratio of SUVmax (B/P ratio) was calculated. Forty‐nine patients (27 men and 22 women) with a diagnosis of lung cancer (small cell lung cancer [SCLC], n = 7; non‐small cell lung cancer [NSCLC], n = 42) with bone metastasis, and a total of 185 bone metastatic lesions were evaluated.

Results

The SUVmax in bone and the B/P ratio were significantly higher in patients with pain and subsequent development of skeletal‐related events than in those without pain or skeletal‐related events, respectively. In addition, the SUVmax in metastatic bone lesions and the B/P ratio in SCLC were significantly lower than those in NSCLC, despite similar FDG uptake in the primary tumor.

Conclusion

Our findings suggest that FDG‐PET evaluation in metastatic bone lesions could be useful to predict initial pain and subsequent clinical outcomes of local bone status in initially diagnosed lung cancer patients with bone metastasis. In addition, our results suggest that there could be histological differences in the biological activity of bone metastatic lesions in lung cancer, especially between SCLC and NSCLC.

Pan-Asian adapted Clinical Practice Guidelines for the management of patients with metastatic non-small-cell lung cancer: a CSCO-ESMO initiative endorsed by JSMO, KSMO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of metastatic non-small-cell lung cancer (NSCLC) was published in 2016. At the ESMO Asia Meeting in November 2017 it was decided by both ESMO and the Chinese Society of Clinical Oncology (CSCO) to convene a special guidelines meeting immediately after the Chinese Thoracic Oncology Group Annual Meeting 2018, in Guangzhou, China. The aim was to adapt the ESMO 2016 guidelines to take into account the ethnic differences associated with the treatment of metastatic NSCLC cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with metastatic NSCLC representing the oncological societies of China (CSCO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence, and was independent of both the current treatment practices and the drug availability and reimbursement situations in the six participating Asian countries. During the review process, the updated ESMO 2018 Clinical Practice Guidelines for metastatic NSCLC were released and were also considered, during the final stages of the development of the Pan-Asian adapted Clinical Practice Guidelines.

Upfront surgery in patients with clinical skip N2 lung cancer based on results of modern radiological examinations

Background

Direct lymphatic drainage from a primary tumor to the right paratracheal or aortic window lymph nodes is often noted in pN2 disease. This multi-institutional retrospective study investigated the outcomes of upfront surgery in patients with clinical skip N2 disease (N2 disease without N1 disease) and a tumor in the right upper lobe or left upper segment based on results of modern radiological examinations, including positron emission tomography (PET).

Methods

We identified 143 patients with cN2 disease who underwent upfront surgery in 12 institutions under the Thoracic Surgery Study Group of Osaka University between January 2006 and December 2013. Among 143 patients, 94 who underwent PET were analyzed. We classified these patients into Group A (n=39; clinical skip N2 disease and a tumor in the right upper lobe or left upper segment) and Group B (n=55; other).

Results

The median follow-up was 56.5 months. Among the 94 patients, 50 (53.2%) had skip N2 disease and 65 (69.1%) had a tumor in the right upper lobe or left upper segment. The 5-year overall survival (OS) rates of the 94 patients with cN2 disease was 47.9%. The 5-year OS rates for the cN2pN0/1 (n=22) and cN2pN2 (n=70) groups were 74.9% and 41.2%, respectively (P=0.034). The univariate analysis of OS revealed no significant differences in age, sex, histology, carcinoembryonic antigen (CEA) level, tumor size, PET findings, and number of metastatic lymph nodes when these parameters were dichotomized. A significantly better 5-year OS rate was observed in Group A than in Group B (64.0% vs. 37.0%; P=0.039). The multivariate analysis of OS revealed that Group A was a significantly prognostic factor (P=0.030).

Conclusions

Patients with cN2 disease in Group A had a more favorable prognosis. Upfront surgery may be a treatment option for such selected patients with non-small lung cancer in the specific group.

Convolutional Neural Networks Promising in Lung Cancer T-Parameter Assessment on Baseline FDG-PET/CT

Aim

To develop an algorithm, based on convolutional neural network (CNN), for the classification of lung cancer lesions as T1-T2 or T3-T4 on staging fluorodeoxyglucose positron emission tomography (FDG-PET)/CT images.

Methods

We retrospectively selected a cohort of 472 patients (divided in the training, validation, and test sets) submitted to staging FDG-PET/CT within 60 days before biopsy or surgery. TNM system seventh edition was used as reference. Postprocessing was performed to generate an adequate dataset. The input of CNNs was a bounding box on both PET and CT images, cropped around the lesion centre. The results were classified as Correct (concordance between reference and prediction) and Incorrect (discordance between reference and prediction). Accuracy (Correct/[Correct + Incorrect]), recall (Correctly predicted T3-T4/[all T3-T4]), and specificity (Correctly predicted T1-T2/[all T1-T2]), as commonly defined in deep learning models, were used to evaluate CNN performance. The area under the curve (AUC) was calculated for the final model.

Results

The algorithm, composed of two networks (a "feature extractor" and a "classifier"), developed and tested achieved an accuracy, recall, specificity, and AUC of 87%, 69%, 69%, and 0.83; 86%, 77%, 70%, and 0.73; and 90%, 47%, 67%, and 0.68 in the training, validation, and test sets, respectively.

Conclusion

We obtained proof of concept that CNNs can be used as a tool to assist in the staging of patients affected by lung cancer.

[Is 18F-PET-CT the First Choice for Preoperative Screening for Ia Non-small Cell Lung Cancer?]

背景与目的

低剂量螺旋计算机断层扫描（computed tomography, CT）筛查高度怀疑为肺癌的肺部阳性结节者，首选外科治疗。在实施外科治疗前如何选择全身筛查方式目前尚不清，本研究旨在探讨采用正电子发射型计算机断层显像（positron emission computed tomography, PET-CT）和常规影像（B-ultrasound/CT/MRI/ECT, BCME）对Ⅰa期非小细胞肺癌（non-small cell lung cancer, NSCLC）术前筛查后患者的无疾病进展期（progression-free survival, PFS）是否存在差异。

方法

回顾性收集170例术前PET-CT筛查和130例BCME筛查的Ⅰa期NSCLC患者，将两组临床基本特征进行倾向值匹配分析（propensity score matching, PSM），两组分别有114例纳入研究。采用Kaplan-Meier生存曲线和Cox回归分析进行生存分析。

结果

经PSM匹配后两组临床基本特征无显著差异。PET-CT组和BCME组的PFS分别为（44.9±27.2）个月、（44.1±33.1）个月，无显著差异（χ²=1.284, P=0.257）。PET-CT组术前筛查假阳性10例，BCME组8例，二者筛查假阳性率无显著差异（χ²=0.241, P=0.623），两种方式均能达到筛查目的，不是PFS的影响因素。

结论

PET-CT和BCME均可用于Ⅰa期NSCLC根治术前筛查，可根据患者实际情况进行个体化选择。

Diagnostic impact of integrated 18F-FDG PET/MRI in cerebral staging of patients with non-small cell lung cancer

Background Integrated positron emission tomography/magnetic resonance imaging (PET/MRI) systems are increasingly being available and used for staging examinations. Brain metastases (BM) are frequent in patients with non-small cell lung cancer (NSCLC) and decisive for treatment strategy. Purpose To assess the diagnostic value of integrated 18F-2-fluoro-2-deoxy-D glucose (18F-FDG) PET/MRI in initial staging in patients with NSCLC for BM in comparison to MRI alone. Material and Methods Eighty-three patients were prospectively enrolled for an integrated 18F-FDG PET/MRI examination. The 3 T MRI protocol included a fluid-attenuated inversion-recovery sequence (FLAIR) and a contrast-enhanced three-dimensional magnetization prepared rapid acquisition GRE sequence (MPRAGE). Two neuroradiologists evaluated the datasets in consensus regarding: (i) present lesions; (ii) size of lesions; and (iii) number of lesions detected in MRI alone, compared to the PET component when reading the 18F-FDG PET/MRI. Results Based on MRI alone, BM were detected in 15 out of the 83 patients, comprising a total of 39 metastases. Based on PET alone, six patients out of the 83 patients were rated positive for metastatic disease, revealing a total of 15 metastases. PET detected no additional BM. The size of the BM correlated positively with sensitivity of detection in PET. Conclusion The sensitivity of PET in detection of BM depends on their size. 18F-FDG PET/MRI does not lead to an improvement in diagnostic accuracy in cerebral staging of NSCLC patients, as MRI alone remains the gold standard.