Percutaneous Fiducial Localization for Thoracoscopic Wedge Resection of Small Pulmonary Nodules

[The role of endoscopy in the management of peripheral pulmonary nodules, part 2: Treatment]

The management of peripheral lung nodules is challenging, requiring specialized skills and sophisticated technologies. The diagnosis now appears accessible to advanced endoscopy (see Part 1), which can also guide treatment of these nodules; this second part provides an overview of endoscopy techniques that can enhance surgical treatment through preoperative marking, and stereotactic radiotherapy treatment through fiduciary marker placement. Finally, we will discuss how, in the near future, these advanced endoscopic techniques will help to implement ablation strategy.

Ten-Year Outcome and Development of Virtual-Assisted Lung Mapping in Thoracic Surgery

Virtual-assisted lung mapping (VAL-MAP) is a preoperative bronchoscopic multispot dye-marking technique used in sublobar lung resection of barely palpable lung nodules. This review summarizes the history and outcomes of the VAL-MAP procedure. VAL-MAP was developed in 2012, and long-term outcomes of lung resection using VAL-MAP have recently been verified. Problems associated with conventional VAL-MAP include a prerequisite of post-mapping computed tomography (CT), occasional inability to see dye marks during surgery, and infrequent resection failure due to deep resection margins; various techniques have been developed to address these issues. VAL-MAP using electromagnetic navigation bronchoscopy with on-site adjustment can omit post-mapping CT. The use of indocyanine green in VAL-MAP has increased the success rate of marking detection during surgery without causing additional complications. VAL-MAP 2.0—a three-dimensional mapping technique that involves the intrabronchial placement of a microcoil—has increased the accuracy of sublobar resection, particularly for deeply located tumors. Although these promising new techniques have some limitations, they are beneficial for sublobar lung resection.

Evaluation of the radiofrequency identification lung marking system: a multicenter study in Japan

BACKGROUND

The radiofrequency identification (RFID) lung marking system is a novel technique using near-field radio-communication technology. The purpose of this study was to investigate the utility and feasibility of this system in the resection of small pulmonary nodules.

METHODS

We retrospectively reviewed clinical records of 182 patients who underwent sublobar resection with the RFID marking system between March 2020 and November 2021 in six tertial hospitals in Japan. Target markings were bronchoscopically made within 3 days before surgery. The contribution of the procedure to the surgery and safety was evaluated.

RESULTS

Target nodule average diameter and depth from the lung surface were 10.9 ± 5.4 mm and 14.6 ± 9.9 mm, respectively. Radiologically, one third of nodules appeared as pure ground-glass nodules (GGNs) on CT. The average distance from target nodule to RFID tag was 8.9 ± 7.1 mm. All surgical procedures were completed by video-assisted thoracoscopic surgery. Planned resection was achieved in all cases without any complications. The surgeons evaluated this system as helpful in 93% (necessary: 67%, useful; 26%) of cases. Nodule radiological features (p < 0.001) and type of surgery (p = 0.0013) were associated with the degree of contribution. In most cases, identification of the RFID tag was required within 1 min despite adhesion (p = 0.27).

CONCLUSION

The RFID lung marking system was found to be safe and effective during successful sublobar resection. Patients with pure GGNs are the best candidates for the system.

Near-Infrared Fluorescence Tumor-Targeted Imaging in Lung Cancer: A Systematic Review

Lung cancer is the most common cancer type worldwide, with non-small cell lung cancer (NSCLC) being the most common subtype. Non-disseminated NSCLC is mainly treated with surgical resection. The intraoperative detection of lung cancer can be challenging, since small and deeply located pulmonary nodules can be invisible under white light. Due to the increasing use of minimally invasive surgical techniques, tactile information is often reduced. Therefore, several intraoperative imaging techniques have been tested to localize pulmonary nodules, of which near-infrared (NIR) fluorescence is an emerging modality. In this systematic review, the available literature on fluorescence imaging of lung cancers is presented, which shows that NIR fluorescence-guided lung surgery has the potential to identify the tumor during surgery, detect additional lesions and prevent tumor-positive resection margins.

Preoperative CT-guided Fiducial Marker Placement for Surgical Localization of Pulmonary Nodules

PURPOSE

To assess the technical success and complication rates of CT-guided fiducial marker placement for the localization of pulmonary nodules and to assess the surgical localization failure rate.

MATERIALS AND METHODS

This was a single-center, retrospective analysis of consecutive patients who underwent CT-guided fiducial marker placement procedures between 2014 and 2020. End points included the technical success of the fiducial marker placement, procedural complications, and the surgical localization failure rate. A two-sample t test and a Fisher exact test were used to compare continuous and categorical variables, respectively. Multivariate logistic regression was used to identify independent risk factors for complications.

RESULTS

A total of 198 preoperative CT-guided fiducial marker placement procedures were performed in 190 patients (mean age, 64 years ± 12 [standard deviation]; 121 women) to localize 205 nodules (mean size, 10 mm ± 4; mean distance to the pleura, 10 mm ± 9). The technical success rate was 98.5% (195 of 198). There were no major complications. A total of 202 nodules were resected during 193 procedures performed 5 days ± 13 after the fiducial marker placement (range, 0-123 days). Surgical localization failure occurred in one patient (0.5%). Of the resected nodules, 146 were lung cancers, 26 nodules were metastases, two were carcinoid tumors, and 28 were benign.

CONCLUSION

The CT-guided fiducial marker placement of pulmonary nodules was safe, effective, and resulted in a low surgical localization failure rate.Keywords: CT, Percutaneous, Thorax, Lung.

A Simple Method to Improve Intraoperative Localization of Fiducial Markers during Lung Resections

Background  Lung cancer screening programs have increased the detection of early-stage lung cancer. High-resolution computed tomography can detect small, low-density pulmonary nodules, or ground-glass opacities. Obtaining a tissue diagnosis can be challenging, often necessitating surgical diagnosis. Preoperative localization and intraoperative fluoroscopy are valuable tools to guide resections for small pulmonary nodules.

Case Description  We present three cases using intraoperative fluoroscopy and Faxitron Bioptics that enhanced our certainty of resection of nonpalpable nodules.

Conclusion  We support the use of intraoperative fluoroscopy with the unique addition of Faxitron BioVision as safe and reliable methods to enhance the certainty of resection.

The accuracy of cone-beam computed tomography and augmented fluoroscopy-guided bronchoscopic marking of multiple small-sized pulmonary nodules in a hybrid operating room: a retrospective cohort study

Background

For the minimally invasive excision of small-sized pulmonary nodules, bronchoscopic markings are increasingly being performed owing to advancements in video-assisted thoracic surgery (VATS). Hybrid operating room equipment is utilized for bronchoscopic VATS markings. We aimed to compare the marking accuracy between bronchoscopic VATS and other marking techniques such as computed tomography-guided percutaneous marking and conventional X-ray fluoroscopy-guided bronchoscopic marking.

Methods

Patients with small-sized pulmonary nodules scheduled to undergo VATS were enrolled in the study. A mixture of 50 to 100 µL of diluted indocyanine green and iopamidol was injected adjacent to the pulmonary nodules as a VATS marker. Patients receiving each of the three image-guided techniques were categorized into group A (computed tomography-guided percutaneous injection), group B (X-ray fluoroscopy-guided virtual bronchoscopy-assisted bronchoscope injection), and group C (cone-beam computed tomography and augmented fluoroscopy-guided virtual bronchoscope-assisted bronchoscopic injection in the hybrid operating room). VATS marking accuracy and procedural complications were compared among the three groups.

Results

In total, 61 patients with 73 pulmonary nodules were eligible for analysis. VATS marking was successful for 15/16 nodules in group A, 28/30 nodules in group B, and 25/27 nodules in group C. Marking accuracy was 5.75±4.59, 15.00±14.02, and 6.05±6.11 (mm), respectively. Multiple markings were successful in 0/1 (0%), 5/6 (83.3%), and 5/5 (100.0%) nodules in groups A, B, and C, respectively. A small pneumothorax occurred in 3/15 (20.0%) patients in group A.

Conclusions

The cone-beam computed tomography and augmented fluoroscopy-guided bronchoscopic approach performed in a hybrid operating room is accurate and equivalent to the computed tomography-guided percutaneous approach, and it enables the VATS marking of multiple pulmonary nodules without causing a secondary pneumothorax.

A Surgeon's Guide for Various Lung Nodule Localization Techniques and the Newest Technologies

Preoperative image-guided localization of lung nodules is necessary for successful intraoperative localization and resection. However, current localization techniques carry significant intraoperative disadvantages for surgeons. Articles were selected through multiple search engines using key search terms and reviewed to compare results, outcomes, advantages, limitations, and complications of various localization methods. Current methods utilize microcoils, hookwires, contrast media, dyes, cyanoacrylate, radiotracers, or fluorescence tracers, which are associated with many intraoperative disadvantages even when paired with other imaging modalities including computed tomography and bronchoscopy techniques. Novel technologies including robotic bronchoscopy, 4-hook anchor, SPiN Thoracic Navigation System, superDimension, Ion Endoluminal System, and the SCOUT system are reviewed including their advantages, which may change the future direction of minimal thoracoscopic surgery with potential to improve intraoperative accuracy and efficiency.

Lung Cancer Screening

Lung cancer is the leading cause of US cancer-related deaths. Lung cancer screening with a low radiation dose chest computed tomography scan is now standard of care for a high-risk eligible population. It is imperative for clinicians and surgeons to evaluate the trade-offs of benefits and harms, including the identification of many benign lung nodules, overdiagnosis, and complications. Integration of smoking cessation interventions augments the clinical benefits of screening. Screening programs must develop strategies to manage screening-detected findings to minimize potential harms. Further research should focus on how to improve patient selection, minimize harms, and facilitate access to screening.

Methylene Blue/Collagen Mixture for CT-Guided Presurgical Lung Nodule Marking: High Efficacy and Safety

PURPOSE

To assess outcomes of computed tomography (CT)-guided methylene blue/collagen marking of preoperative lung nodules before video-assisted thoracoscopic surgery (VATS) and robotic-assisted thoracic surgery (RATS).

MATERIALS AND METHODS

A retrospective cohort study assessing 25 methylene blue/collagen solution CT-guided lung nodule localization procedures on 26 nodules in 25 patients was performed. The procedures were performed by a fellowship-trained radiologist 1-2 hours before scheduled surgery under local anesthesia. Approximately 4-6 ml of methylene blue/collagen solution was injected in a perinodular location under CT guidance with a 19-gauge trocar needle and along the track to the visceral pleural surface. Post-procedural CT images confirmed appropriate lung nodule location marking.

RESULTS

Perinodular CT-guided trocar needle placement was achieved in all marking procedures (n = 26/26). Increased consolidation near the target nodule was also demonstrated in all patients on the post-procedural localized CT scans. One patient with moderate emphysema developed a small to moderate-sized pneumothorax (∼20%-30%), and an 8-Fr thoracentesis catheter was placed under CT guidance before surgery. There was no bleeding or hemoptysis in any patient. Methylene blue/collagen solution was readily visible by the thoracic surgeon in association with all target nodules. One patient required conversion to open procedure due to the proximal portion of the right lower lobe pulmonary artery segmental branch. Of the 26 identified nodules, pathology specimens confirmed the adequacy of nodule resection in all cases.

CONCLUSIONS

Preoperative CT-guided methylene blue/collagen solution injection offers a safe and highly effective technique for marking subpleural lung nodules undergoing VATS or RATS.

Multicenter, prospective, observational study of a novel technique for preoperative pulmonary nodule localization

OBJECTIVES

Minimally invasive surgery provides an ideal method for pathologic diagnosis and curative intent of small pulmonary nodules (SPNs); however, the main problem with thoracoscopic resection is the difficulty in locating the nodules. The goal of this study was to determine the safety and feasibility of a new localization technique tailored for SPNs.

METHODS

A computed tomography (CT)-guided technique, which has a tri-colored suture and claw with 4 fishhook-shaped hooks, was designed to localize SPN preoperatively. Then a multicenter, prospective study was conducted to evaluate the safety and feasibility of this device. The primary endpoints included safety (asymptomatic/symptomatic pneumothorax or parenchymal hemorrhage, and unanticipated adverse effects) and success rate (precise placement and device fracture, displacement, or dislodgement). The secondary endpoints included feasibility (duration of the localization procedure and device fracture or fault) and patient comfort (pain).

RESULTS

A total of 90 SPNs were localized from 80 patients. Overall, no symptomatic complications requiring medical intervention, with the exception of asymptomatic pneumothorax (n = 7 [7.8%]) and lung hemorrhages (n = 5 [5.6%]), were observed. The device was successfully placed without dislodgment or movement in 87 of 90 lesions (96.7%). The median nodule size was 0.70 cm (range, 0.30-1.0 cm). The median duration of the procedure was 15 minutes (range, 7-36 minutes). No patient complained of notable pain during or after the procedure.

CONCLUSIONS

This new device for SPNs is safe, and has a high success rate, feasibility and good tolerance.

Intraoperative Detection and Assessment of Lung Nodules

Lung cancer is the most frequent cause of cancer-related death worldwide. Despite advances in systemic therapy, the 5-year survival remains humbling at 4% to 17%. For those diagnosed early, surgical therapy can yield potentially curative results. Surgical resection remains a cornerstone of medical care. Success hinges on sound oncologic resection principles. Various techniques can be used to identify pulmonary nodules. A challenge is intraoperative assessment of the surgical specimen to confirm disease localization and ensure an R0 resection. The primary tool is frozen section. Understanding the options available enhances the arsenal of thoracic surgeons and leads to better patient care.

Electromagnetic navigational bronchoscopy-directed dye marking for locating pulmonary nodules

BACKGROUND

Small peripheral pulmonary nodules, which are usually deep-seated with no visual markers on the pleural surface, are often difficult to locate during surgery. At present, CT-guided percutaneous techniques are used to locate pulmonary nodules, but this method has many limitations. Thus, we aimed to evaluate the accuracy and feasibility of electromagnetic navigational bronchoscopy (ENB) with pleural dye to locate small peripheral pulmonary nodules before video-associated thoracic surgery (VATS).

METHODS

The ENB localisation procedure was performed under general anaesthesia in an operating room. Once the locatable guide wire, covered with a sheath, reached the ideal location, it was withdrawn and 0.2-1.0 mL of methylene blue/indocyanine green was injected through the guide sheath. Thereafter, 20-60 mL of air was instilled to disperse the dye to the pleura near the nodules. VATS was then performed immediately.

RESULTS

Study subjects included 25 patients with 28 nodules. The mean largest diameter of the pulmonary nodules was 11.8 mm (range, 6.0-24.0 mm), and the mean distance from the nearest pleural surface was 13.4 mm (range, 2.5-34.9 mm). After the ENB-guided localisation procedure was completed, the dye was visualised in 23 nodules (82.1%) using VATS. The average duration of the ENB-guided pleural dye marking procedure was 12.6 min (range, 4-30 min). The resection margins were negative in all malignant nodules. Complications unrelated to the ENB-guided localisation procedure occurred in two patients, including one case of haemorrhage and one case of slow intraoperative heart rate.

CONCLUSION

ENB can be used to safely and accurately locate small peripheral pulmonary nodules and guide surgical resection.

TRIAL REGISTRATION NUMBER

ChiCTR1900021963.

Intraoperative localization of small pulmonary nodules to assist surgical resection: A novel approach using a surgical navigation puncture robot system

Background

Localization and resection of nonvisible, nonpalpable pulmonary nodules during video‐assisted thoracoscopic surgery is challenging. In this study we developed a surgical navigation puncture robot system in order to locate small pulmonary nodules before thoracoscopic surgery.

Methods

Four pigs were divided into group A and group B and underwent positioning puncture with the aid of the robotic system. The pigs in group A breathed freely during the experiment, whilst mechanical ventilation was used on the pigs in group B.

Results

Using the robotic system to locate nodules achieved good results. For group A, a total of nine simulated nodules were created and successfully localized. The mean positioning accuracy was 9.6 ± 4.9 mm (range, 3.2–17.4 mm), and the time required for system positioning was 7.1 ± 1.0 minutes (range, 5.6–8.2 minutes). For group B, a total of 23 simulated nodules were created and successfully localized. The mean positioning accuracy was 2.9 ± 1.5 mm (range, 0.7–5.9 mm), and the time required for system positioning was 7.8 ± 1.1 minutes (range, 6.3–9.7 minutes).

Conclusions

The new method using a surgical navigation puncture robot system to locate small pulmonary nodules is feasible and safe, and its positioning accuracy is sufficient to meet clinical requirements. In addition, results indicated that breathing had a great influence on the positioning accuracy, mainly in the longitudinal direction. Our surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting.

Key points

Significant findings of the study: A new method using a surgical navigation puncture robot system was developed to locate small pulmonary nodules before thoracoscopic surgery. The results indicated that this method can provide accurate localization and permit smaller and more precise resections.

What this study adds: A surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting.

Image-guided Preoperative Localization of Pulmonary Nodules for Video-assisted and Robotically Assisted Surgery

Video-assisted thoracic surgery (VATS) and robotically assisted surgery are used increasingly for minimally invasive diagnostic and therapeutic resection of pulmonary nodules. Unsuccessful localization of small, impalpable, or deep pulmonary nodules can necessitate conversion from VATS to open thoracotomy. Preoperative localization techniques performed by radiologists have improved the success rates of VATS resection for small and subsolid nodules. Any center at which VATS diagnostic resection of indeterminate pulmonary nodules is performed should be supported by radiologists who offer preoperative nodule localization. Many techniques have been described, including image-guided injection of radioisotopes and radiopaque liquids and placement of metallic wires, coils, and fiducial markers. These markers enable the surgeon to visualize the position of an impalpable nodule intraoperatively. This article provides details on how to perform each percutaneous localization technique, and a group of national experts with established nodule localization programs describe their preferred approaches. Special reference is made to equipment required, optimization of marker placement, prevention of technique-specific complications, and postprocedural treatment. This comprehensive unbiased review provides valuable information for those who are considering implementation or optimization of a nodule localization program according to workflow patterns, surgeon preference, and institutional resources in a particular center. ^©RSNA, 2019.

Placement of markers to assist minimally invasive resection of peripheral lung lesions

With development of lung cancer screening programs and increased utilization of radiographic imaging there is significantly higher detection of smaller lung nodules and subsolid lesions. These nodules could be malignant and pose a diagnostic challenge. Video-assisted thoracoscopic surgery and robotic-assisted thoracoscopic surgery (RATS) represent minimally invasive methods for tissue sampling. Intraoperative identification of these lesions maybe difficult, requiring marking prior to surgery. We review different techniques for the placement of markers to assist in the resection of peripheral lung lesions (PLL).

Electromagnetic Transthoracic Nodule Localization for Minimally Invasive Pulmonary Resection

BACKGROUND

Increased use of chest computed tomography and the institution of lung cancer screening have increased the detection of ground-glass and small pulmonary nodules. Intraoperative localization of these lesions via a minimally invasive thoracoscopic approach can be challenging. We present the feasibility of perioperative transthoracic percutaneous nodule localization using a novel electromagnetic navigation platform.

METHODS

This is a multicenter retrospective analysis of a prospectively collected database of patients who underwent perioperative electromagnetic transthoracic nodule localization before attempted minimally invasive resection between July 2016 and March 2018. Localization was performed using methylene blue or a mixture of methylene blue and the patient's blood (1:1 ratio). Patient, nodule, and procedure characteristics were collected and reported.

RESULTS

Thirty-one nodules were resected from 30 patients. Twenty-nine of 31 nodules (94%) were successfully localized. Minimally invasive resection was successful in 93% of patients (28/30); 7% (2/30) required conversion to thoracotomy. The median nodule size was 13 mm (interquartile range 25%-75%, 9.5-15.5), and the median depth from the surface of the visceral pleura to the nodule was 10 mm (interquartile range 25%-75%, 5.0-15.9). Seventy-one percent (22/31) of nodules were malignant. No complications associated with nodule localization were reported.

CONCLUSIONS

The use of intraoperative electromagnetic transthoracic nodule localization before thoracoscopic resection of small and/or difficult to palpate lung nodules is safe and effective, potentially eliminating the need for direct nodule palpation. Use of this technique aids in minimally invasive localization and resection of small, deep, and/or ground-glass lung nodules.

Peripheral Lung Nodule Diagnosis and Fiducial Marker Placement Using a Novel Tip-Tracked Electromagnetic Navigation Bronchoscopy System

BACKGROUND

Electromagnetic navigation (EMN) has improved bronchoscopic access to peripheral pulmonary nodules. A novel EMN system utilizing novel tip-tracked instruments for endobronchial [electromagnetic navigation bronchoscopy (ENB)] as well as transthoracic lung biopsy [electromagnetic-guided transthoracic needle aspiration (EMTTNA)] has become available. The system provides real-time feedback as well as the ability to biopsy lesions outside of the airway. These advances have the potential to improve diagnostic yield over previous EMN systems.

METHODS

We performed a retrospective review of consecutive peripheral bronchoscopy cases utilizing a novel EMN platform for biopsy and/or fiducial marker (FM) placement at a tertiary care university hospital. We analyzed factors that may influence diagnostic yield including lesion size.

RESULTS

Our study included 108 patients who underwent EMN-guided bronchoscopy between June 2015 and April 2017 for the diagnosis of peripheral lung lesions and/or the placement of FMs for stereotactic body radiotherapy. Ninety-three patients underwent biopsy utilizing ENB +/- EMTTNA. The combined diagnostic yield was 78%. EMTTNA provided a diagnosis for 5 patients in whom the ENB biopsy results were negative. Diagnostic yield by nodules <20, 20 to 30, and >30 mm in size was 30/45 (67%), 27/30 (90%), and 16/18 (89%), respectively. Sixty-five patients underwent FM placement with a total of 133 FM placed.

CONCLUSION

This novel tip-tracked EMN system incorporating both ENB and EMTTNA can guide biopsy and FM placement with a high degree of success and with a low complication rate. Multicentered prospective trials are required to develop algorithmic approaches to combine ENB and EMTTNA into a single procedure.

Electromagnetic Navigation Bronchoscopy Localization Versus Percutaneous CT-Guided Localization for Lung Resection via Video-Assisted Thoracoscopic Surgery: A Propensity-Matched Study

Background: An ideal preoperative localization method is essential for the resection of small and deep-seated pulmonary nodules by video-assisted thoracoscopic surgery (VATS) in the era of low-dose computed tomography (CT) screening. This study describes a new localization method using electromagnetic navigation bronchoscopy (ENB) and compares it against conventional percutaneous CT-guided methods. Methods: Between January 2016 and May 2018, 18 consecutive patients with a total of 27 pulmonary nodules underwent ENB localization using patent blue vital dye before thoracoscopy for lung resection at the National Taiwan University Hospital. Over the same period, 268 patients had a total of 325 pulmonary nodules localized by a CT-guided method. Propensity analysis was applied to minimize bias during comparison. Results: Patients were selected using a propensity-score based process, matched for potential risk factors for localization failure, to ensure equal potential prognostic factors in both groups. After matching, the ENB group had 15 patients with a total of 24 pulmonary nodules, and the CT group had 30 patients with 48 pulmonary nodules. No major procedure-related complications occurred in either group. The target pulmonary nodule was not successfully localized for one patient in the ENB group and three in the CT group. The lesions were fully excised after conversion to mini-thoracotomy. Pathological examination confirmed the accuracy of the dye staining. Analysis found a non-significant difference in the success rate of these two localization methods. However, the following parameters were significantly different: interval between localization to surgery, global time, and rate of pneumothorax (p < 0.05). Conclusions: In the era of minimally invasive surgery, surgeons need an efficient one-step way to manage pulmonary nodules. Patent blue vital injection with ENB guidance in the operating room is a new, effective approach to localize small, deep-seated and non-palpable pulmonary lesions, comparable with CT-guided localization.

Simultaneous cone beam computed tomography-guided bronchoscopic marking and video-assisted thoracoscopic wedge resection in a hybrid operating room

The increasing need for pulmonary resection by video‐assisted thoracoscopic surgery (VATS) has presented a greater opportunity to detect small‐sized pulmonary nodules by computed tomography (CT). In cases where it is difficult to identify tumor localization intraoperatively, it is necessary to place the VATS marker near the pulmonary nodules before surgery. Conventional percutaneous or bronchoscopic VATS marker placement under local anesthesia is accompanied by patient pain. We clinically applied a new technique to place VATS markers using a bronchoscope under general anesthesia in a hybrid operating room. Multiple pulmonary nodules were successfully marked and securely excised simultaneously by VATS. This technique enables secure, minimally invasive resection of multiple small‐sized pulmonary nodules without causing distress to the patient.

Computed tomography-guided dye localization for deeply situated pulmonary nodules in thoracoscopic surgery

Background

Increased lung cancer screening of asymptomatic adults using low-dose computed tomography (CT) with high-resolution imaging modalities has increased the identification of small and deeply situated pulmonary nodules. This study aimed to evaluate the role of preoperative patient blue vital (PBV) dye localization for an undiagnosed nodule deeply situated in the lung parenchyma followed by minimally invasive lung resection.

Methods

From July 2013 to December 2016, 27 consecutive patients (16 women, median age: 62 years) with small undiagnosed pulmonary nodules at a depth of more than 30 mm underwent preoperative CT-guided PBV dye localization followed by thoracoscopic diagnostic resection of the nodule at National Taiwan University Hospital. The clinical characteristics were collected retrospectively to evaluate the efficacy and safety of the procedure.

Results

The median size of pulmonary nodule in preoperative CT images was 11 mm with a median depth of 31.6 mm (range, 30.0-48.6 mm). Of the 27 nodules, 8 were pure ground-glass nodules, 3 were pure solid nodules, and 16 were partially solid nodules. The diagnostic yield of CT-guided dye localization following diagnostic wedge resection was 100%. The final pathological diagnoses were: primary adenocarcinoma of the lung (n=20), adenocarcinoma in situ (n=1), and benign nodules (n=6). Only asymptomatic complications were noted after localization, and the median hospital stay was 3 days [interquartile range (IQR), 3-4 days]. All of 21 patients were cancer-free after a median follow-up of 39.0 months (IQR, 29.5-50.0 months).

Conclusions

This study indicated that preoperative, percutaneous CT-guided PBV dye localization for undiagnosed nodules at a depth of more than 30 mm could be a safe and feasible procedure. Furthermore, it was considerably advantageous for preserving the lung parenchyma, especially for benign nodules.

Hybrid operating room for the intraoperative CT-guided localization of pulmonary nodules

Video-assisted thoracic surgery (VATS) requires preoperative computed tomography (CT)-guided localization of small pulmonary nodules or ground glass opacities (GGOs). However, this traditional two-stage approach is not devoid of potential complications, including wire dislodgement, pneumothorax, and/or hemothorax. With the advent of hybrid operating rooms (HORs), simultaneous single-stage localization and removal of such lesions has become possible. Here, we review the technical developments and the state-of-the-art in the field of intraoperative CT-guided localization and resection of small pulmonary nodules performed within a HOR.

Ultrasound for intraoperative localization of lung nodules during thoracoscopic surgery

In low-dose CT screening era, an ideal preoperative localization method is essential for resection of small and deep-seated pulmonary nodules by video-assisted thoracoscopic surgery (VATS). This article focuses on intraoperative ultrasonography localization method during thoracoscopy. Performing ultrasonography intraoperatively is a real-time and alternative approach to localize small, non-visible and non-palpable pulmonary lesions without injury to lung parenchyma. Its widespread usage has been limited due to the air in the lung parenchyma; however, its application can be useful in some conditions with guidance to find the lesion.

Intraoperative fluorescence imaging in thoracic surgery

Intraoperative fluorescence imaging (IFI) can improve real-time identification of cancer cells during an operation. Phase I clinical trials in thoracic surgery have demonstrated that IFI with second window indocyanine green (TumorGlow^® ) can identify subcentimeter pulmonary nodules, anterior mediastinal masses, and mesothelioma, while the use of a folate receptor-targeted near-infrared agent, OTL38, can improve the specificity for diagnosing tumors with folate receptor expression. Here, we review the existing preclinical and clinical data on IFI in thoracic surgery.

High-resolution computed tomography features and CT-guided microcoil localization of subcentimeter pulmonary ground-glass opacities: radiological processing prior to video-assisted thoracoscopic surgery

Background

With the rapid development of high-resolution computed tomography (HRCT), low-dose CT scanning and video-assisted thoracoscopic surgery (VATS), smaller pulmonary nodules can be detected. Subcentimeter ground-glass opacities (GGOs) are extremely difficult to diagnose and accurately locate during VATS and in surgically resected specimens.

Methods

From September 2013 to September 2017, 42 subcentimeter GGO lesions (≤1 cm) in 31 patients who underwent CT-guided microcoil insertion followed by VATS resection were included. All HRCT images were assessed by two experienced radiologists, and CT-guided microcoil localization procedures were performed by two experienced interventional radiologists.

Results

A total of 42 subcentimeter GGOs included 28 malignancies (66.7%) and 14 benign lesions (33.3%). The diameter of malignant GGOs (8.52±1.46 mm) was significantly larger than that of benign lesions (7.04±1.52 mm) (P<0.05). Seven patients had more than one GGO nodule. There were no significant differences in the location, composition, shape, margins, presence of air bronchograms, presence of the pleural indentation sign and presence of the vascular convergence sign between benign and malignant GGOs (P>0.05). All the localization procedures were performed successfully. A small pneumothorax occurred in 9 patients (21.4%), and minor hemorrhage in the lung parenchyma occurred in 8 patients (19.0%). All GGOs were easily identified during VATS and were definitively diagnosed.

Conclusions

Common HRCT features cannot be used as criteria for the differential diagnosis of subcentimeter benign and malignant pulmonary GGOs. CT-guided microcoil marking of these lesions prior to VATS is a feasible, safe, and effective procedure for the localization of subcentimeter pulmonary GGOs.

The feasibility of electromagnetic navigational bronchoscopic localization with fluorescence and radiocontrast dyes for video-assisted thoracoscopic surgery resection

Recently, some groups have reported the utilization of electromagnetic navigational bronchoscopy (ENB) for localization of pulmonary lesion. Its application for intraoperative visual localization with dyes to determine the target area has been increasing. In this paper, we reviewed the feasibility of ENB utilization for video-assisted thoracoscopic surgery (VATS) or robotic sublobar resection as a localization tool, and its future application in minimally invasive thoracic surgery.

Electromagnetic navigation bronchoscopy-Chungnam National University Hospital experience

Background

To find small pulmonary nodules or ground grass nodules (GGNs) with video-assisted thoracoscopic surgery (VATS) is very difficult. There are several conventional methods to localize small nodules or GGNs, which require additional radiation exposure and may cause some complications such as pneumothorax or hemothorax. We aimed to evaluate the effectiveness and feasibility of electromagnetic navigational bronchoscopy-guided pulmonary localization in a minimally invasive thoracic surgery field.

Methods

We retrospectively reviewed the medical records from a prospectively collected database of the patients who underwent ENB procedure for biopsy and/or localization of pulmonary resection at the Chungnam National University Hospital from January 2017 to January 2018.

Results

A total of 37 ENB-guided dye-markings or biopsies for 37 lesions in 30 patients were performed. Thirty-two ENB-guided localizations using dye-marking for resection were performed in 25 patients. The median nodule size was 9 mm (IQR: 7-13 mm), and the median distance from the pleura was 6 mm (IQR: 3-10 mm). The failure of an ENB-guided localization was noted in 4 cases (12.5%). There was no major complication noted with the procedure, and just two patients showed mild intrabronchial bleeding stopped spontaneously. The most common lobar location was right lower lobe (11 cases, 34.4%), and all cases of localization failure were right lower lobe. A pathologic diagnosis was obtained from surgically resected specimen (not from ENB biopsy: 32 of 32 localizations, 100%), neoplastic lesions were 23 cases (72%). Of them, a primary lung cancer and metastatic lung cancer were noted in 11 cases, and in 11cases, respectively. All margins of the nodules were negative.

Conclusions

The ENB-guided dye localization by a well-trained thoracic surgeon enables accurate intraoperative identification of GGN or a small pulmonary nodule, with minimal complications and enables minimally invasive surgery including single port surgery.

Lung Cancer Biopsies

Image-guided percutaneous transthoracic needle biopsy (PTNB) is a well-established and minimally invasive technique for evaluating pulmonary nodules. Implementation of a national lung screening program and increased use of chest computed tomography have contributed to the frequent identification of indeterminate pulmonary nodules that may require tissue sampling. The advent of biomarker-driven lung cancer therapy has led to increased use of repeat PTNB after diagnosis. Percutaneous insertion of markers for preoperative localization of small nodules can aid in minimally invasive surgery and radiation treatment planning. This article discusses PTNB, patient selection, and biopsy technique, including minimizing and managing complications.

Pleural Dye Marking Using Radial Endobronchial Ultrasound and Virtual Bronchoscopy before Sublobar Pulmonary Resection for Small Peripheral Nodules

BACKGROUND

Minimally invasive surgery of pulmonary nodules allows suboptimal palpation of the lung compared to open thoracotomy.

OBJECTIVE

The objective of this study was to assess endoscopic pleural dye marking using radial endobronchial ultrasound (r-EBUS) and virtual bronchoscopy to localize small peripheral lung nodules immediately before minimally invasive resection.

METHODS

The endoscopic procedure was performed without fluoroscopy, under general anesthesia in the operating room immediately before minimally invasive surgery. Then, 1 mL of methylene blue (0.5%) was instilled into the guide sheath, wedged in the subpleural space. Wedge resection or segmentectomy were guided by visualization of the dye on the pleural surface. Contribution of dye marking to the surgical procedure was rated by the surgeon.

RESULTS

Twenty-five nodules, including 6 ground glass opacities, were resected in 22 patients by video-assisted thoracoscopic wedge resection (n = 11) or robotic-assisted thoracoscopic surgery (10 segmentectomies and 1 wedge resection). The median greatest diameter of nodules was 8 mm. No conversion to open thoracotomy was needed. The endoscopic procedure added an average 10 min to surgical resection. The dye was visible on the pleural surface in 24 cases. Histological diagnosis and free margin resection were obtained in all cases. Median skin-to-skin operating time was 90 min for robotic segmentectomy and 40 min for video-assisted wedge resection. The same operative precision was considered impossible by the surgeon without dye marking in 21 cases.

CONCLUSIONS

Dye marking using r-EBUS and virtual bronchoscopy can be easily and safely performed to localize small pulmonary nodules immediately before minimally invasive resection.

Near-infrared dye marking for thoracoscopic resection of small-sized pulmonary nodules: comparison of percutaneous and bronchoscopic injection techniques

BACKGROUND

Minimally invasive video-assisted thoracoscopic surgery for small-sized pulmonary nodules is challenging, and image-guided preoperative localisation is required. Near-infrared indocyanine green fluorescence is capable of deep tissue penetration and can be distinguished regardless of the background colour of the lung; thus, indocyanine green has great potential for use as a near-infrared fluorescent marker in video-assisted thoracoscopic surgery.

METHODS

Thirty-seven patients with small-sized pulmonary nodules, who were scheduled to undergo video-assisted thoracoscopic wedge resection, were enrolled in this study. A mixture of diluted indocyanine green and iopamidol was injected into the lung parenchyma as a marker, using either computed tomography-guided percutaneous or bronchoscopic injection techniques. Indications and limitations of the percutaneous and bronchoscopic injection techniques for marking nodules with indocyanine green fluorescence were examined and compared.

RESULTS

In the computed tomography-guided percutaneous injection group (n = 15), indocyanine green fluorescence was detected in 15/15 (100%) patients by near-infrared thoracoscopy. A small pneumothorax occurred in 3/15 (20.0%) patients, and subsequent marking was unsuccessful after a pneumothorax occurred. In the bronchoscopic injection group (n = 22), indocyanine green fluorescence was detected in 21/22 (95.5%) patients. In 6 patients who underwent injection marking at 2 different lesion sites, 5/6 (83.3%) markers were successfully detected.

CONCLUSION

Either computed tomography-guided percutaneous or bronchoscopic injection techniques can be used to mark pulmonary nodules with indocyanine green fluorescence. Indocyanine green is a safe and easily detectable fluorescent marker for video-assisted thoracoscopic surgery. Furthermore, the bronchoscopic injection approach enables surgeons to mark multiple lesion areas with less risk of causing a pneumothorax.

TRIAL REGISTRATION

UMIN-CTR R000027833 accepted by ICMJE. Registered 5 January 2013.

Thoracoscopic anatomical lung segmentectomy using 3D computed tomography simulation without tumour markings for non-palpable and non-visualized small lung nodules

OBJECTIVES

Although wedge resection can be curative for small lung tumours, tumour marking is sometimes required for resection of non-palpable or visually undetectable lung nodules as a method for identification of tumours. Tumour marking sometimes fails and occasionally causes serious complications. We have performed many thoracoscopic segmentectomies using 3D computed tomography simulation for undetectable small lung tumours without any tumour markings. The aim of this study was to investigate whether thoracoscopic segmentectomy planned with 3D computed tomography simulation could precisely remove non-palpable and visually undetectable tumours.

METHODS

Between January 2012 and March 2016, 58 patients underwent thoracoscopic segmentectomy using 3D computed tomography simulation for non-palpable, visually undetectable tumours. Surgical outcomes were evaluated.

RESULTS

A total of 35, 14 and 9 patients underwent segmentectomy, subsegmentectomy and segmentectomy combined with adjacent subsegmentectomy, respectively. All tumours were correctly resected without tumour marking. The median tumour size and distance from the visceral pleura was 14 ± 5.2 mm (range 5-27 mm) and 11.6 mm (range 1-38.8 mm), respectively. Median values related to the procedures were operative time, 176 min (range 83-370 min); blood loss, 43 ml (range 0-419 ml); duration of chest tube placement, 1 day (range 1-8 days); and postoperative hospital stay, 5 days (range 3-12 days). Two cases were converted to open thoracotomy due to bleeding. Three cases required pleurodesis for pleural fistula. No recurrences occurred during the mean follow-up period of 44.4 months (range 5-53 months).

CONCLUSIONS

Thoracoscopic segmentectomy using 3D computed tomography simulation was feasible and could be performed to resect undetectable tumours with no tumour markings.

Image-guided surgery and therapy for lung cancer: a critical review

Of the many imaging technologies, some have the potential to be used in image-guided surgery and therapy (IGS/IGT). This review of relevant papers on IGS/IGT for lung cancer indicates effective localization and IGS/IGT in early endobronchial lesions by fluorescence bronchoscopic technique. Visualization of early peripheral (nodular) tumors at operation can be achieved by a variety of imaging methods and devices which allow identification, localization and provision of intraoperative real-time images. Recent developments employing fluorescence contrasts and near infra-red light have shown encouraging feasibility and outcome in providing reliable methods for the IGS of cancer generally and lung cancer more specifically with provision of real time intraoperative imaging. The concept of the hybrid operating theater is touched upon.

Image-guided techniques for localizing pulmonary nodules in thoracoscopic surgery

Low-dose computed tomography (LDCT) screening has increased the detection rate for small pulmonary nodules with ground-glass opacity (GGO) in the peripheral lung parenchyma. Minimally invasive thoracoscopic surgery for these lung nodules is challenging for thoracic surgeons, and image-guided preoperative localization is mandatory for their successful resection. Image-guided localization methods primarily include two imaging tools: computed tomography (CT) and bronchoscopy. These different methods may use different localized materials, including hookwires, dyes, microcoils, fiducial markers, contrast media, and radiotracers. Ultrasonography and near-infrared imaging are also used for intraoperative localization of lung lesions. In this article, we review different localization techniques and discuss their indications and limitations.

Electromagnetic Navigation Bronchoscopy-Guided Dye Marking for Thoracoscopic Resection of Pulmonary Nodules

BACKGROUND

Computed tomography scans are increasingly used not only for lung cancer screening but also for staging and evaluation of other cancers. As a result, more patients with pulmonary nodules, many with subcentimeter lesions, are being referred to thoracic surgeons, some with concern for primary lung neoplasm and others with possible metastatic lung lesions. Obtaining a definitive diagnosis of these lesions is difficult. Electromagnetic navigational bronchoscopy (ENB)-guided pleural dye marking followed by thoracoscopic resection is a novel alternative technique for definitive diagnosis. The main objective of this study was to evaluate the feasibility and our initial experience with ENB-guided dye localization and minimally invasive resection for diagnosis of lung lesions.

METHODS

Selected patients with lung lesions underwent ENB-guided dye marking and minimally invasive resection. The primary end points were the rate of nodule localization and definitive diagnosis of the nodule.

RESULTS

We performed ENB-guided localization and minimally invasive resection in 29 patients. The median lesion size was 10 mm, with a median distance from pleural surface of 13 mm. The operative mortality was 0%. The median hospital stay was 3 days. The nodule was localized and resected, and a definitive diagnosis was obtained in all patients (29 of 29; 100%). The nodule was neoplastic in 19 patients. All malignant lesions were completely resected with negative microscopic margins.

CONCLUSIONS

Our initial experience with ENB-guided dye localization and minimally invasive resection found that the technique was feasible, safe, and successful in the diagnosis of small lung lesions. Thoracic surgeons should further investigate this method and incorporate it into their armamentarium.

Management of CT screen-detected lung nodule: the thoracic surgeon perspective

Implementation of lung cancer CT screening programs will increase the incidence of pulmonary nodules and require multidisciplinary efforts for devising appropriate treatment plans. The role of the thoracic surgeon is paramount in leading the discussion and shaping the treatment strategies. Management of CT screen-detected lung nodules differ from conventional lung cancer nodules given their smaller size, varied histologies and potentially indolent growth. Here we present a brief overview of the thoracic surgeon's perspective on the clinical evaluation, diagnostic tests and surgical approach to these nodules in the setting of a comprehensive lung cancer screening program.

Hybrid theatre and alternative localization techniques in conventional and single-port video-assisted thoracoscopic surgery

Management of pulmonary nodules in terms of diagnosis and intraoperative localization can be challenging, especially in the minimal invasive video-assisted thoracoscopic surgery (VATS) approach, and may be even more difficult with single port VATS with limited access. The ability to localize small lesions intraoperatively is particularly important for excisional biopsy for diagnostic frozen section, as well as to guide sublobar resection. Some of the common techniques to aid localization include preoperative percutaneous hookwire localization, colour dye or radio-dye labelling injection of the nodule or adjacent site to allowing visualization or detection by radioactive counter intraoperatively. The use of hybrid operating room (OR) for intraoperative localization of lung nodules was first reported in 2013, and was called image guided VATS (iVATS). Subsequently, we have expanded the iVATS application for single port VATS major lung resection of small or ground-glass opacity lesions. By performing an on-table cone-beam CT scan, real-time and accurate assessment of the pulmonary lesion can be made, which can aid the localization process. Other types of physical or colour marker that can be deployed percutaneously in the hybrid OR immediate before surgery can enhance haptic feedback and sensitivity of digital palpation, as well as provide a radiopaque nidus for radiological confirmation. In the past decade, the electromagnetic navigation bronchoscopy (ENB) technology had developed into a useful adjunct technology for the localization of peripheral lung nodules by injection of marking agent or deployment of fiducial to the lesion through the endobronchial route causing much lower marking agent diffusion and artefacts. Recently, the combination of hybrid OR and ENB for lung nodule localization and marking has further increased the accuracy and applicability of the technology. The article will be exploring the latest development of the above approaches to lung nodule localization, and discuss some of the techniques' advantages and flaws.

Preoperative computed tomography-guided percutaneous localization of ground glass pulmonary opacity with polylactic acid injection

Localization of a ground glass nodule is a difficult challenge for thoracic surgeons, especially for ground glass opacities (GGOs) less than 10 mm in diameter. In this study we implement a new method for preoperative localization of pulmonary (GGOs). From October 2013 to December 2014, computed tomography-guided percutaneous polylactic acid injection localizations were performed for five pulmonary nodules in five patients (2 men and 3 women; mean age, 59.8 years; range, 54–65 years). The injection was feasible in all patients and the localization effect was excellent. The total procedure duration was 12.6 minutes (range; 10–15) and the volume of polylactic acid injected was 0.38 mL. The wedge resections were easily and successfully performed in all five cases. The cutting margin was no less than 2 cm from the lesion. This technique is promising for the determination of GGO location in thoracoscopic surgery for wedge resection.

Radioguided video-assisted resection of non-palpable solitary pulmonary nodule/ground glass opacity: how to do it

BACKGROUND

Detection of subcentimeter solitary pulmonary nodules (SPN) and ground glass opacities (GGO) is increased but their small size may make them difficult to be reached by computerized tomography (CT) guided fine needle agobiopsy or transbronchial biopsy. Surgical resection provides the gold standard for obtaining a specimen for histopathologic diagnosis, and video-assisted thoracic surgery (VATS) allows in many cases a minimally invasive technique of resections. The limit of VATS techniques is the need of nodule localization. Often-digital palpation is all needed to identify the appropriate area of resection, but sometimes it may be very difficult to identify and remove small, deep, non-palpable lesions. The criteria for nodule marking are unclear and variety of localization methods have been developed and they are effective but burdened by significant failure rate and complications. To increase the efficacy of thoracoscopic localization/ resection of small pulmonary nodules, we used the radioguided technique.

METHODS

Under CT guidance, the nodule was identified and a needle was inserted to reach lesional or perilesional tissue. A solution of ^99mtechnetium (^99mTc) macro-aggregates albumin diluted with iodized contrast medium was injected. After injection, CT was performed to confirm precise staining.

RESULTS

At VATS, a gamma detector probe allowed localization of nodules in all patients. Resection was performed, and suture margins were checked with the probe to search for residual hyperabsorption. All specimens underwent frozen section. Frozen section revealed diagnosis in all cases.

CONCLUSIONS

Radioguided surgery is a cost-effective strategy for evaluating suspicious SPN/GGO with a success rate close to 100%, extremely low morbidity, and zero mortality. Radioguided VATS may be useful for preoperative localization of deep, small lung nodules that cannot be digitally localized or for GGO opacities that can be difficult to palpate even with the open technique.