An update on the role of advanced diagnostic bronchoscopy in the evaluation and staging of lung cancer

Learning Curve of Real-Time Imaging with C-Arm Based Tomography for Peripheral Lung Nodule Biopsy

The number of procedures required to attain proficiency with new bronchoscopic biopsy technologies for peripheral pulmonary lesions (PPLs) is uncertain. A prospective, single-center study evaluated learning curves of two operators performing PPL biopsies using a novel, real-time, intraoperative tomographic imaging system in consecutive procedures in adults with CT-detected PPLs. Operators were considered “proficient” when they asked three or fewer questions of the manufacturer’s clinical representative with no subsequent navigations in which they asked more than three questions. A total of 31 procedures were performed on 31 patients (Operator 1: 18, Operator 2: 13). Proficiency was achieved after an average of 10 procedures (Operator 1: 12, Operator 2: 8). From the learning curve to the post-learning curve period, the number of questions (median [IQR]: 23 [9.5–41.5] versus 0 [0–1], p < 0.001) and radiation dose (median [IQR]: 19.5 mGy/m2 [1.9–43.5] versus 1.5 mGy/m2 [0.7–3.3], p = 0.05) decreased significantly; procedure time decreased (median [IQR]: 12 min [7–20] versus 8 min [3–15], p = 0.29); and diagnostic yield increased significantly (13/20 cases [65%] to 11/11 cases [100%]), (p = 0.03). Based on this unique, clinically relevant method of assessing learning curve, proficiency with the Body Vision system was achieved at approximately the tenth procedure. These findings require validation in larger, diverse populations.

Safety and Feasibility of Photodynamic Therapy for Ablation of Peripheral Lung Tumors

BACKGROUND

Newer navigational bronchoscopy technologies render peripheral lung lesions accessible for biopsy and potential treatment. We investigated whether photodynamic therapy (PDT) delivered via navigational bronchoscopy is feasible and safe for ablation of peripheral lung tumors.

METHODS

Two studies evaluated PDT in patients with solid peripheral lung tumors followed by clinical follow-up (nonresection study, N=5) or lobectomy (resection study, N=10). Porfimer sodium injection was administered 40 to 50 hours before navigational bronchoscopy. Lesion location was confirmed by radial probe endobronchial ultrasonography. An optical fiber diffuser was placed within or adjacent to the tumor under fluoroscopic guidance; laser light (630 nm wavelength) was applied at 200 J/cm of diffuser length for 500 seconds. Tumor response was assessed by modified Response Evaluation Criteria in Solid Tumors at 3 and 6 months postprocedure (nonresection study) and pathologically (resection study).

RESULTS

There were no deaths, discontinuations for adverse events, or serious or grade ≥3 adverse events related to study treatments. Photosensitivity reactions occurred in 8 of 15 patients: 6 mild, 1 moderate, 1 severe (elevated porphyrins noted in blood after treatment). Among 5 patients with clinical follow-up, 1 had complete response, 3 had stable disease, and 1 had progressive disease at 6 months follow-up. Among 10 patients who underwent lobectomy, 1 had no evidence of tumor at resection (complete response), 3 had 40% to 50% tumor cell necrosis, 2 had 20% to 35%, and 4 had 5% to 10%.

CONCLUSION

PDT for nonthermal ablation of peripheral lung tumors was feasible and safe in this small study. Further study is warranted to evaluate efficacy and corroborate the safety profile.

Diagnostic value of adenosine deaminase in bronchoalveolar lavage fluid for patients with lung cancer

BACKGROUND

Lung cancer is both the most common seen malignity and cause of cancer-related deaths worldwide. Adenosine deaminase (ADA) is a hydrolytic enzyme that catalyses the conversion of adenosine to inosine in the purine metabolism pathway. Studies examining ADA levels in bronchoalveolar lavage (BAL) fluids of patients with lung malignancy are very limited in the literature. Our aim examine the clinical significance of ADA levels in BAL fluids of patients with lung malignancy.

METHODS

A total of 89 patients undergoing fiberoptic bronchoscopy (FOB) with different indications from December 2017 to December 2018 were included in this study. The patients were divided into two groups as malignancy and non-malignancy groups. Demographic, laboratory data and ADA levels in bronchoalveolar lavage (BAL) were compared between the two groups. In addition, ADA levels in BAL were compared among the histopathological subtypes of patients in the malignant group.

RESULTS

The mean age of the patients was 58.2 ± 14.5 years with 86% of male gender. ADA enzyme levels were statistically higher in the malignant patient group compared with the non-malignant group (37.2 [17.6-71] vs 17.1 [9-35.3], P < .001). When the patients in the malignant group were compared in terms of ADA levels according to their histopathological types, a statistically significant difference was obtained in small cell carcinoma patients (49 [12.5-75.3], P = .005).

CONCLUSION

ADA levels in BAL may be a diagnostic biomarker in lung malignancies. In patients where a biopsy cannot be taken or histopathological typing cannot be performed because of tissue insufficiency, ADA levels in BAL can be an auxiliary parameter in making malignancy / histopathological diagnosis accompanied by radiological and clinical findings.

Toward optical spectroscopy-guided lung biopsy: Demonstration of tissue-type classification

The diagnostic yield of standard tissue-sampling modalities of suspected lung cancers, whether by bronchoscopy or interventional radiology, can be nonoptimal, varying with the size and location of lesions. What is needed is an insitu sensor, integrated in the biopsy tool, to objectively distinguish among tissue types in real time, not to replace biopsy with an optical diagnostic, but to verify that the sampling tool is properly located within the target lesion. We investigated the feasibility of elastic scattering spectroscopy (ESS), coupled with machine learning, to distinguish lung lesions from the various nearby tissue types, in a study with freshly-excised lung tissues from surgical resections. Optical spectra were recorded with an ESS fiberoptic probe in different areas of the resected pulmonary tissues, including benign-margin tissue sites as well as the periphery and core of the lesion. An artificial-intelligence model was used to analyze, retrospectively, 2032 measurements from excised tissues of 35 patients. With high accuracy, ESS was able to distinguish alveolar tissue from bronchi, alveolar tissue from lesions, and bronchi from lesions. This ex vivo study indicates promise for ESS fiberoptic probes to be integrated with surgical intervention tools, to improve reliability of pulmonary lesion targeting.

Implications of Preoperative Transbronchial Lung Biopsy for Non-small Cell Lung Cancer Less than 3-cm

BACKGROUND/AIM

Transbronchial lung biopsy (TBLB) has been recommended for patients with suspected lung cancer. However, its diagnostic value is limited to small lesions, and some studies have indicated that biopsy might be related to metastasis and/or dissemination. This study aimed to evaluate the outcomes after preoperative TBLB for non-small cell lung cancer (NSCLC) patients.

PATIENTS AND METHODS

Data were reviewed from 371 patients with resected pN0 NSCLC less than 3-cm. Patients were divided into two groups: TBLB and Non-TBLB. Recurrence-free survival (RFS) curves were plotted using the Kaplan-Meier method. Cox regression analyses were used to evaluate the hazard ratio (HR) with the endpoint RFS.

RESULTS

The 5-year RFS rates were 75.5% in the TBLB group and 91.4% in the Non-TBLB group (p<0.001). Poor RFS was independently associated with TBLB (HR=2.491, 95%CI=1.337-4.640; p=0.004).

CONCLUSION

Preoperative TBLB may adversely affect RFS among NSCLC patients with small size tumours.

A Randomized Controlled Trial on Optimal Sampling Sequence in Radial Guide Sheath Endobronchial Ultrasound Lung Biopsy

BACKGROUND

An optimal sampling sequence in radial guide sheath endobronchial ultrasound lung biopsy (R-EBUS) is unclear. This prospective single-center pilot randomized controlled trial aimed to determine if the initial method and sequence of sampling affect the diagnostic accuracy of the procedure.

METHODS

Consecutive patients undergoing R-EBUS for lesions >15 mm with a bronchus sign were randomly assigned (1:1:1) to biopsy first (group A), brushings first (group B) or combination (group C). The primary outcome was a positive diagnosis from any sampling method.

RESULTS

Fifty-four patients were randomized. The overall diagnostic yield of the procedure was 77.8% (95% confidence interval: 66%-89%), with no difference between groups. A higher rate of positive cytology from brushings was seen if the biopsies were performed before brushings (77.8% in group A vs. 44.4% in group B, P=0.03). The rate of positive cytology from washings was higher if the washings were obtained just after the brushings (61.1% in group A vs. 11.1% in group B, P=0.02). There was no difference in the rate of positive biopsy histology in the groups (P=0.27). All 3 sampling modalities were more likely to be positive in group A (50.0% vs. 11.1% in group B and 22.2% in group C, P=0.04). Complications rate was low and not significantly different between groups.

CONCLUSION

The overall rate of a positive R-EBUS procedure was not affected by the initial sampling method or sequence. However, all 3 sampling modalities were more likely to be positive if biopsies were performed first, followed by brushings and washings.

Prospective Analysis of a Novel Endobronchial Augmented Fluoroscopic Navigation System for Diagnosis of Peripheral Pulmonary Lesions

BACKGROUND

Navigational bronchoscopy has improved upon traditional bronchoscopy to identify suspicious pulmonary lesions, but wide variability exists in the diagnostic yield of various modalities. The aim of this study was to measure localization accuracy and diagnostic yield of a novel endobronchial augmented fluoroscopic navigation system (first-generation LungVision system) for peripheral pulmonary lesions (PPLs).

METHODS

This prospective single-center study included adults undergoing guided bronchoscopy to evaluate PPLs. Preprocedure computed tomography (CT) images were obtained, and planning software calculated a pathway to the lesion. A flexible bronchoscope was used to navigate along the pathway overlaid on the intraprocedural fluoroscopic image. When real-time display indicated the catheter tip had reached the lesion, cone-beam computed tomography (CBCT) was used to measure the actual location of the tip. Biopsy and rapid on-site cytopathologic evaluation were performed.

RESULTS

Fifty-one patients were included in the analysis. The median lesion diameter was 18.0 mm (range: 7.0 to 48.0 mm). Localization success was 96.1%. The average distance between lesion location as shown by LungVision augmented fluoroscopy and actual location measured by CBCT was 5.9 mm (range: 2.1 to 10.0 mm). Diagnostic yield at the index procedure was 78.4%. Diagnostic accuracy assessed at 12 months follow-up was 88.2%. Average CT-to-body divergence was 14.5 mm (range: 2.6 to 33.0 mm) from preprocedure CT to intraprocedural CBCT images.

CONCLUSION

Augmented fluoroscopy for navigation and biopsy of PPLs with the LungVision system showed a high localization success rate and corresponding high diagnostic yield. Navigation and biopsy with real-time visualization can improve diagnostic yield for PPLs.

Bronchial arterial embolization may reduce the risk of severe bleeding in central airway obstruction due to renal cell carcinomas during bronchoscopic procedures

BACKGROUND

Hemorrhage is a life-threatening complication during bronchoscopic intervention in patients with central airway obstruction (CAO) due to metastatic renal cell carcinoma (RCC). Whether pre-bronchoscopic bronchial arterial embolization (BAE) can reduce the risk of severe bleeding in CAO patients due to metastatic RCC remains unclear.

METHODS

A total of 31 CAO patients due to metastatic RCC were included retrospectively and divided into a BAE group (receiving pre-bronchoscopic BAE) and non-BAE group in this study. Based on computed tomography (CT) and bronchoscopic findings, tumor debulking was used to reconstruct the airway during interventional bronchoscopy. The primary outcome was the incidence of severe bleeding during bronchoscopic procedures. Bleeding-related complications, Karnofsky performance score (KPS) and dyspnea score were also analyzed over a 1-month observation period.

RESULTS

There were no significant differences between the two groups in baseline characteristics, including patients' features, tumor morphology under CT scannings, tumor site, and obstruction degree under bronchoscopic examination. Procedure-related bleeding occurred in all 31 patients. Pre-bronchoscopic BAE significantly reduced the incidence of moderate and major bleeding when compared with that in the non-BAE group. The incidence of poor visualization and hypoxia was also reduced significantly in the BAE group. There was no significant difference in KPS and dyspnea score between the BAE and non-BAE groups at 1 month follow up.

CONCLUSION

Pre-bronchoscopic BAE might be a feasible option to reduce the risk of severe bleeding for CAO patients due to metastatic RCC during bronchoscopic intervention. Interventional bronchoscopy was a safe and effective procedure for CAO due to metastatic RCC.The reviews of this paper are available via the supplemental material section.

Long non-coding RNA RFPL3S is a novel prognostic biomarker in lung cancer

Long non-coding RNAs (lncRNAs) are functional components of the human genome. Recent studies have demonstrated that lncRNAs play essential roles in tumorigenesis, and are involved in cell proliferation, apoptosis, migration and invasion in several types of tumor, including lung cancer. However, the clinical relevance of lncRNA expression in lung cancer remains unknown. The aim of the present study was to investigate the expression pattern of RFPL3 antisense (RFPL3S) and its associations with clinicopathological characteristics in patients with lung cancer. Whether RFPL3S can act as a potential prognostic biomarker for lung cancer was also investigated. RFPL3S expression in tumor samples and cells was assessed using the Oncomine database and the Cancer Cell Line Encyclopedia, respectively. Based on Kaplan-Meier Plotter analyses, the prognostic values of RFPL3S were further evaluated. It was revealed that RFPL3S was highly expressed in lung cancer tissues when compared with normal tissues and was significantly associated with pN factor, pTNM stage and Ki-67 labeling index. In the survival analyses, increased RFPL3S expression was associated with poor survival and was inversely associated with first progression in all patients. These results indicate that RFPL3S may be of clinical significance and may act as a prognostic biomarker in lung cancer.

Devices for image-guided lung interventions: State-of-the-art review

Lung cancer is the leading cause of cancer-related death. According to the American Cancer Society, there were an estimated 222,500 new cases of lung cancer and 155,870 deaths from lung cancer in the United States in 2017. Accurate localization in lung interventions is one of the keys to reducing the death rate from lung cancer. In this study, a total of 217 publications from 2006 to 2017 about designs of medical devices for localization in lung interventions were screened, shortlisted, and categorized by localization principle and reviewed for functionality. Each study was analyzed for engineering characteristics and clinical significance. Research regarding interventional imaging equipment, navigation systems, and surgical devices was reviewed, and both research prototypes and commercial products were discussed. Finally, the future directions and existing challenges were summarized, including real-time intra-procedure guidance, accuracy of localization, clinical application, clinical adoptability, and clinical regulatory issues.

Machine learning to predict lung nodule biopsy method using CT image features: A pilot study

Computed tomography (CT)-based screening on lung cancer mortality is poised to make lung nodule management a growing public health problem. Biopsy and pathologic analysis of suspicious nodules is necessary to ensure accurate diagnosis and appropriate intervention. Biopsy techniques vary as do the specialists that perform them and the ways lung nodule patients are referred and triaged. The largest dichotomy is between minimally invasive biopsy (MIB) and surgical biopsy (SB). Cases of unsuccessful MIB preceding a SB can result in considerable delay in definitive care with potentially an adverse impact on prognosis besides potentially avoidable healthcare expenditures. An automated method that predicts the optimal biopsy method for a given lung nodule could save time and healthcare costs by facilitating referral and triage patterns. To our knowledge, no such method has been published. Here, we used CT image features and radiologist-annotated semantic features to predict successful MIB in a way that has not been described before. Using data from the Lung Image Database Consortium image collection (LIDC-IDRI), we trained a logistic regression model to determine whether a MIB or SB procedure was used to diagnose lung cancer in a patient presenting with lung nodules. We found that in successful MIB cases, the nodules were significantly larger and more spiculated. Our model illustrates that using robust machine learning tools on easily accessible semantic and image data can predict whether a patient's nodule is best biopsied by MIB or SB. Pending further validation and optimization, clinicians could use our publicly accessible model to aid clinical decision-making.

Timely follow-up of positive cancer screening results: A systematic review and recommendations from the PROSPR Consortium

Timely follow-up for positive cancer screening results remains suboptimal, and the evidence base to inform decisions on optimizing the timeliness of diagnostic testing is unclear. This systematic review evaluated published studies regarding time to follow-up after a positive screening for breast, cervical, colorectal, and lung cancers. The quality of available evidence was very low or low across cancers, with potential attenuated or reversed associations from confounding by indication in most studies. Overall, evidence suggested that the risk for poorer cancer outcomes rises with longer wait times that vary within and across cancer types, which supports performing diagnostic testing as soon as feasible after the positive result, but evidence for specific time targets is limited. Within these limitations, we provide our opinion on cancer-specific recommendations for times to follow-up and how existing guidelines relate to the current evidence. Thresholds set should consider patient worry, potential for loss to follow-up with prolonged wait times, and available resources. Research is needed to better guide the timeliness of diagnostic follow-up, including considerations for patient preferences and existing barriers, while addressing methodological weaknesses. Research is also needed to identify effective interventions for reducing wait times for diagnostic testing, particularly in underserved or low-resource settings. CA Cancer J Clin 2018;68:199-216. © 2018 American Cancer Society.

PD-L1 immunohistochemistry for non-small cell lung carcinoma: which strategy should be adopted?

INTRODUCTION

PD-L1 detection with immunohistochemistry (IHC) is the only predictive biomarker available to date for PD-L1/PD1 immunotherapy in thoracic oncology. While many studies have been published on this biomarker, they raise a number of questions concerning mainly, (i) the type of antibody for use and its condition of utilization, (ii) the threshold to be used, (iii) the message and information to communicate to the thoracic oncologist and, (iv) the adoption of this methodology as part of the daily practices of a pathology laboratory. Areas covered: This review provides an update on the use of the different PD-L1 antibodies for IHC in the context of metastatic non-small cell lung cancer (NSCLC) and discusses their use as companion or complementary diagnostic tests. The limits of PD-L1 IHC as a predictive test, the precautions to be adopted as well as some perspectives will then be considered. Expert commentary: IHC for PD-L1 can be considered as a theranostic test, which implies providing an extremely reliable result that avoids any false positive and negative results. PD-L1 IHC requires considerable expertise and specific training of pathologists. PD-L1 IHC can be a companion or complementary diagnostic test depending on the clone employed, the molecular therapy prescribed and the indication of use.