Combined Endosonographic Mediastinal Lymph Node Staging in Positron Emission Tomography and Computed Tomography Node-Negative Non-Small-Cell Lung Cancer in High-Risk Patients

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.

Differentiation of intrathoracic lymph node histopathology by volumetric dual energy CT radiomic analysis

PURPOSE

To determine the performance of volumetric dual energy low kV and iodine radiomic features for the differentiation of intrathoracic lymph node histopathology, and influence of contrast protocol.

MATERIALS AND METHODS

Intrathoracic lymph nodes with histopathologic correlation (neoplastic, granulomatous sarcoid, benign) within 90 days of DECT chest imaging were volumetrically segmented. 1691 volumetric radiomic features were extracted from iodine maps and low-kV images, totaling 3382 features. Univariate analysis was performed using 2-sample t-test and filtered for false discoveries. Multivariable analysis was used to compute AUCs for lymph node classification tasks.

RESULTS

129 lymph nodes from 72 individuals (mean age 61 ± 15 years) were included, 52 neoplastic, 51 benign, and 26 granulomatous-sarcoid. Among all contrast enhanced DECT protocol exams (routine, PE and CTA), univariable analysis demonstrated no significant differences in iodine and low kV features between neoplastic and non-neoplastic lymph nodes; in the subset of neoplastic versus benign lymph nodes with routine DECT protocol, 199 features differed (p = .01- < 0.05). Multivariable analysis using both iodine and low kV features yielded AUCs >0.8 for differentiating neoplastic from non-neoplastic lymph nodes (AUC 0.86), including subsets of neoplastic from granulomatous (AUC 0.86) and neoplastic from benign (AUC 0.9) lymph nodes, among all contrast protocols.

CONCLUSIONS

Volumetric DECT radiomic features demonstrate strong collective performance in differentiation of neoplastic from non-neoplastic intrathoracic lymph nodes, and are influenced by contrast protocol.

Lobar or sublobar resection of peripheral stage I non-small cell lung cancer

PURPOSE OF REVIEW

We aim to highlight two recent clinical trials that have altered the approach of the management of stage I nonsmall cell lung cancer.

RECENT FINDINGS

The JCOG 0802 and CALGB 140503 trials demonstrated that sublobar resection is noninferior to lobectomy for overall and disease-free survival in patients with stage I nonsmall cell lung cancer.

SUMMARY

Since 1962, lobectomy has been deemed the gold standard treatment for operable lung cancer. However, two recent clinical trials have demonstrated that, for select patients, sublobar resection is oncologically noninferior; results, which are leading us into a new era for the surgical management of lung cancer. Notwithstanding the progress made by these studies and the opportunities that have been put forth, questions remain. This review aims at reviewing the results of both trials and to discuss future perspectives for the surgical treatment of lung cancer.

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.

Interventional Pulmonology and Esophagus: Combined Endobronchial Ultrasound and Endoscopic Ultrasound for Mediastinal Staging

Endoscopic ultrasound (EUS) techniques in addition to endobronchial ultrasound (EBUS) can lead to diagnosis and complete accurate staging of the mediastinum in a single session. This allows for decreased health care costs, less delay in diagnosis and treatment, reduced patient discomfort, and decreased morbidity compared with invasive surgical staging techniques. In comparison to conventional mediastinoscopy, the cost-effectiveness and reduced complication profile of the endoscopic approach has made this a superior initial step in the staging and diagnosis of lung cancer. Moreover, compared with EBUS alone, combined EUS and EBUS has significantly increased yield, as well as diagnostic sensitivity making a combined approach preferable as the emerging gold-standard technique for initial minimally invasive mediastinal staging. We discuss the advantage of using EUS in combination with EBUS and highlight techniques, lymph node landmarks, utility in staging and restaging of the mediastinum, roles in diagnosing mediastinal infections and granulomatous lesions, and future directions in endosonography.

Development and validation of tumor-to-blood based nomograms for preoperative prediction of lymph node metastasis in lung cancer

Background

To develop and validate tumor‐to‐blood based nomograms for preoperative prediction of lymph node (LN) metastasis in patients with lung cancer (LC).

Methods

A prediction model was developed in a primary cohort comprising 330 LN stations from patients with pathologically confirmed LC, these data having been gathered from January 2016 to June 2019. Tumor‐to‐blood variables of LNs were calculated from positron emission tomography‐computed tomography (PET‐CT) images of LC and the short axis diameters of LNs were measured on CT images. Tumor‐to‐blood variables, number of stations suspected of harboring LN metastasis according to PET, and independent clinicopathological risk factors were included in the final nomograms. After being internally validated, the nomograms were used to assess an independent validation cohort containing 101 consecutive LN stations accumulated from July 2019 to March 2020.

Results

Four tumor‐to‐blood variables (left atrium, inferior vena cava, liver, and aortic arch) and the maximum standardized uptake value (SUVmax) for LNs were found to be significantly associated with LN status (p < 0.001 for both primary and validation cohorts). Five predictive nomograms were built. Of these, one with LN SUVmax/left atrium SUVmax was found to be optimal for predicting LN status with AUC 0.830 (95% confidence interval [CI]: 0.774–0.886) in the primary cohort and AUC 0.865 (95% CI: 0.782–0.948) in the validation cohort. All models showed good discrimination, with a modest C‐index, and good calibration in both primary and validation cohorts.

Conclusions

We have developed tumor‐to‐blood based nomograms that incorporate identified clinicopathological risk factors and facilitate preoperative prediction of LN metastasis in LC patients.

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.