Preoperative flexible bronchoscopy in patients with persistent ground-glass nodule

Diagnostic Yield of Shape-Sensing Robotic-Assisted Bronchoscopy for Ground-Glass Nodules and Subsolid Nodules with a Solid Component Less than 6 mm

BACKGROUND

Ground-glass pulmonary nodules (GGNs) are most commonly sampled by percutaneous transthoracic biopsy. Diagnostic yield for ground-glass nodules using robotic-assisted bronchoscopy has been scarcely described, with a reported yield of 70.6%.

OBJECTIVES

The aim of this study is to assess diagnostic yield for GGNs using shape-sensing robotic-assisted bronchoscopy (ssRAB).

METHOD

A retrospective study of patients who underwent ssRAB for evaluation of GGNs, from September 2021 to April 2023. Primary outcome was diagnostic yield of ssRAB for GGNs, secondary outcomes were sensitivity for malignancy, and complications that required admission or intervention.

RESULTS

A total of 23 nodules were biopsied from 22 patients. Median age was 71 years (IQR 66-81), 63.6% were female, and 40.9% had a previous history of cancer. Forty-three percent of nodules were in the right upper lobes, and the median lesion size was 1.8 × 1.21. Twelve were subsolid nodules (SSNs), and 11 were pure GGNs. Overall diagnostic yield was 87%, with a sensitivity for malignancy of 88.9%. Adenocarcinoma was the most common malignancy diagnosed (70%). No procedure-related complications were reported.

CONCLUSION

The use of ssRAB shows a high diagnostic yield for diagnosing GGN and SSN with less than 6 mm solid component with a low risk for complications.

A narrative review of the clinical approach to subsolid pulmonary nodules

Background and Objective

The widespread use of chest computed tomography (CT) for lung cancer screening has led to increased detection of subsolid pulmonary nodules. The management of subsolid nodules (SSNs) is challenging since they are likely to grow slowly and a long-term follow-up is needed. In this review, we discuss the characteristics, natural history, genetic features, surveillance, and management of SSNs.

Methods

PubMed and Google Scholar were searched to identify relevant articles published in English between January 1998 and December 2022 using the following keywords: "subsolid nodule", "ground-glass nodule (GGN)", and "part-solid nodule (PSN)".

Key Content and Findings

The differential diagnosis of SSNs includes transient inflammatory lesions, focal fibrosis, and premalignant or malignant lesions. Long-term CT surveillance follow-up is needed to manage SSNs that persist for >3 months. Although most SSNs have an indolent clinical course, PSNs may have a more aggressive clinical course than pure GGNs. The proportion of growth and the time to grow is higher and shorter in PSN than pure GGN. In lung adenocarcinoma manifesting as SSNs, EGFR mutations were the major driver mutations. Guidelines are available for the management of incidentally detected and screening-detected SSNs. The size, solidity, location, and number of SSNs are important factors in determining the need for surveillance and surgical resection, as well as the interval of follow-up. Positron emission tomography/CT and brain magnetic resonance imaging (MRI) are not recommended for the diagnosis of SSNs, especially for pure GGNs. Periodic CT surveillance and lung-sparing surgery are the main strategies for the management of persistent SSNs. Nonsurgical treatment options for persistent SSNs include stereotactic body radiotherapy (SBRT) and radiofrequency ablation (RFA). For multifocal SSNs, the timing of repeated CT scans and the need for surgical treatment are decided based on the most dominant SSN(s).

Conclusions

The SSN is a heterogeneous disease and a personalized medicine approach is required in the future. Future studies of SSNs should focus on their natural history, optimal follow-up duration, genetic features, and surgical and nonsurgical treatments to improve the corresponding clinical management. All these efforts will lead to the personalized medicine approach for the SSNs.

Development and Validation of a Prediction Model for Positive Findings of Preoperative Flexible Bronchoscopy in Patients with Peripheral Lung Cancer

(1) Background: It has yet to be determined whether preoperative flexible bronchoscopy (FB) should be routinely performed in patients with peripheral lung cancer. The aim of this study was to construct a model to predict the probability of positive FB findings, which would help assess the necessity of preoperative FB. (2) Methods: A total of 380 consecutive patients with peripheral lung cancer who underwent preoperative FB were recruited for this study. A prediction model was developed through univariate and multivariate logistic regression, with predictors including gender, age, body mass index (BMI), smoking, history of chronic lung diseases, respiratory symptoms, lesion size, lesion type, lesion location in the bronchi, and lesion location in the lobe. The predictive performance of the model was evaluated by validation using 1000 iterations of bootstrap resampling. Model discrimination was assessed using the area under the receiver operating characteristics curve (AUC), and calibration was assessed using the Brier score and calibration plots. (3) Results: The model suggested that male patients with respiratory symptoms, decreased BMI, solid lesions, and lesions located in lower-order bronchi were more likely to have positive FB findings. The AUC and Brier score of the model for internal validation were 0.784 and 0.162, respectively. The calibration curve for the probability of positive FB findings showed convincing concordance between the predicted and actual results. (4) Conclusions: Our prediction model estimated the pretest probability of positive FB findings in patients with peripheral lung cancers. Males and patients with lower BMI, the presence of respiratory symptoms, larger lesions, solid lesions, and lesions located in lower-order bronchi were associated with increased positive FB findings. The use of our model can be of assistance when making clinical decisions about preoperative FB.

Risk factors for invisible intraoperative markings after virtual-assisted lung mapping

BACKGROUND

Virtual-assisted lung mapping (VAL-MAP) is a preoperative bronchoscopic multi-spot dye-marking technique, which can be combined with bronchoscopic placement of a microcoil (VAL-MAP 2.0). VAL-MAP can identify unpalpable pulmonary lesions; however, the markings are occasionally deemed invisible intraoperatively. We investigated preoperative risk factors for invisible markings after VAL-MAP.

METHODS

We prospectively performed preoperative VAL-MAP in patients at the University of Tokyo between January 2014 and June 2020. Data of 219 patients (257 lesions) and 857 markings were retrospectively reviewed. Dye markings were categorized as Grade 0 (invisible) or 1-5 (visible). The risk factors for Grade 0 markings were assessed using multiple logistic regression analysis. Subsegments of the bronchus showing Grade 0 markings were also evaluated for 133 lesions and 504 markings without missing data for the target segment.

RESULTS

Sixty-one of the 257 lesions (24%) displayed >1 Grade 0 markings. Seventy-six (8.9%) of the 857 markings were Grade 0 intraoperatively. VAL-MAP 1.0 was performed for 202 (79%) and 25 lesions (10%) without and with electromagnetic navigation bronchoscopy, and VAL-MAP 2.0 with a microcoil was performed for 30 lesions (11%). Upper lobe markings were associated with a significantly increased risk of invisible markings. There was no significant difference in the frequency of Grade 0 markings among the VAL-MAP methods. Among all bronchi subsegments, left B1+2c exhibited the highest rate of Grade 0 markings.

CONCLUSIONS

Markings placed using VAL-MAP are more likely to be invisible for upper lobe pulmonary lesions. Injecting markings for lesions in the left S1+2c thus require caution.

Technologies for targeting the peripheral pulmonary nodule including robotics

Bronchoscopic sampling of PPL was significantly advanced by the development of the endobronchial ultrasound guide sheath method in the 1990s. Since then, a range of technical and procedural techniques have further advanced diagnostic yields. These include the use of thinner bronchoscopes with better working channel diameters, understanding the importance of peripheral transbronchial needle aspiration, and virtual bronchoscopic assistance. These have enabled better sampling of smaller and more technically challenging lesions including ground-glass nodules. Most recently, robotic bronchoscopy has been developed which, among other refinements, allows fine control of visual bronchoscopic navigation by replacing movements directed by the hand with electronic consoles and trackballs, and innovatively integrate virtual with real bronchoscopic pathways. The requirement for PPL diagnosis and treatment is expected to increase with more chest CT performed as part of CT screening programmes.

Electromagnetic navigation bronchoscopy: clinical utility in the diagnosis of lung cancer

Electromagnetic navigation bronchoscopy (ENB) is one of several technological advances which have broadened the indications for bronchoscopy in the diagnostic workup of lung cancer. The technique facilitates bronchoscopic sampling of peripheral pulmonary nodules as well as mediastinal lymph nodes, although wide availability and expertise in endobronchial ultrasonography has limited its application in routine clinical practice to the former. ENB in this setting is quite versatile and may be considered an established alternative to more invasive techniques, especially in selected patients with underlying pulmonary disease or comorbidities at high risk for complications from computer topography-guided fine needle aspiration or surgical resection. Nodule sampling may be performed with a variety of instruments, including forceps, cytology brushes, and transbronchial needles. Although samples are generally small, they are often suitable for molecular analysis.