Ion Robotic Bronchoscopy and Da Vinci Robotic Resection for a Solitary Pulmonary Nodule

The authors present a case of Ion robotic bronchoscopy and robotic lung resection for a solitary pulmonary nodule. The patient was a 68-year-old man and never smoker who presented with an enlarging right lower lobe solitary pulmonary nodule. It was first seen on chest x-ray in 2016 and enlarged on serial imaging to its greatest size of 16 by 12 millimeters in 2019. The patient had a significant medical history of right shoulder melanoma that was resected, coronary artery disease, and obstructive sleep apnea.

Thin slice computed tomography (CT) imaging was obtained for staging purposes and preprocedural planning. The nodule measured 16 by 17 by 15 millimeters. A positron emission tomography (PET) scan was obtained for further staging, which showed a mass in the right lower lobe of the lung with a maximum standard uptake value of 16.4. There was no evidence of mediastinal or hilar avidity and there was no evidence of extrathoracic disease. There was a small area of avidity in the right shoulder that was evaluated and negative for malignancy.

During preoperative evaluation, pulmonary function tests were obtained, which showed a first forced expiratory volume of 123% and a diffusing capacity of lung for carbon monoxide of 86% - both were adequate for lobectomy. The patient was interested in pursuing diagnosis prior to consideration of definitive treatment. He therefore consented to robotic navigational bronchoscopy with mediastinal lymph node sampling, prior to any surgical procedure.

For robotic bronchoscopy, the patient was placed under general anesthesia with paralysis in the supine position. The pathway to the nodule was customized prior to the procedure based on the individual's CT scan. A standard bronchoscopy was performed prior to navigation for airway clearance. The robot was positioned and docked. The authors began by matching virtual bronchoscopy to real-time bronchoscopy. They marked the main carina for orientation. They then registered each lobe by driving into each subsegment of the lower lobe and then the apical segments of the bilateral upper lobes. Only the right side is featured in the video. As the bronchoscope was guided into the peripheral airways, shape sensing technology identified exactly how far the bronchoscope had traveled in the distal airways. Once the computer had enough information to detect the presence within a specific lobe, the lobe was illuminated as seen in the bottom left screen.

The authors then begin navigation. Virtual bronchoscopy shows the customized path in the bottom left corner. Real time bronchoscopy is seen in the bottom right. There was constant feedback in terms of the distance to the location and the pleural boundaries as is denoted by the anatomy border.

The bronchial tree is pictured to provide an overview of the relationship between the bronchoscope, the nodule, and the carina at all times. This can identify if the bronchoscopist has strayed from the planned pathway. In this case, an endoluminal aspect of the lesion is seen during real-time bronchoscopy, which confirmed the location of the bronchoscope.

Once the bronchoscopist was within close proximity to the target, radial endobronchial ultrasound bronchoscopy (EBUS) was used to detect an appropriate signal coinciding with the lesion, as seen in the bottom left screen.

Biopsies were taken with a 23-gauge flexible needle through the catheter, which had not been moved since the radial EBUS probe had been withdrawn. CT to body divergence can occur particularly in the lower lobes, suggesting that one may be closer or farther away virtually than they actually are in real time. Once biopsies were taken, the specimens were read with rapid pathologic evaluation on-site to confirm sampling of the nodule in question rather than sampling of benign lung parenchyma around the lesion. For lesions that are smaller than 15 millimeters in size, this can happen easily.

Once adequate tissue samples were obtained, the optical probe was then inserted once again through the catheter to confirm adequate hemostasis. The robotic bronchoscope was withdrawn and undocked from the patient, and standard EBUS was performed for mediastinal staging. Two lymph nodes were identified on EBUS, and both yielded lymphocytes on preliminary and final pathology without evidence of metastasis.

The pathology of the primary lesion was significant for poorly differentiated non-small cell cancer favoring adenocarcinoma. After recovery, segmentectomy versus lobectomy for definitive treatment of the nodule was discussed with the patient. The decision was made to perform a robotic-assisted lobectomy with mediastinal lymphadenectomy for three main reasons: first, the aggressive nature of the nodule as evidenced by the standardized update value (SUV) on PET scan and histologic characteristics; second, there was a possibility of an inadequate parenchymal margin with a segmentectomy; and third, the patient's pulmonary function tests showed he could tolerate a lobectomy. The patient had no complications following his robotic bronchoscopy and was discharged that afternoon with plans to return the following day for surgery.

For the robotic resection, the patient was placed in the left lateral decubitus position with a double lumen endotracheal tube in preparation for right chest surgery. A standard procedural pause was performed and the right lung was deflated. The authors placed a single camera port in the anterior axillary line along the 9th interspace. This would eventually become robot arm three. A left atrial retractor was placed in robot arm one and a fenestrated grasper in arm two. The Maryland bipolar dissector was used in arm four. A separate assistant port was placed between arms three and four. This was one interspace below in a vertical line to facilitate specimen extraction at the end of the case.

Robotic resection was performed. On initial exploration, there was no evidence of disseminated pleural disease or abnormal pleural fluid. The inferior pulmonary ligament was identified and exposed. Using the fenestrated grasper and bipolar dissector, the inferior pulmonary ligament was divided. As lymph nodes were exposed in stations 8 and 9R, they were removed with the bipolar dissector and sent for intraoperative frozen pathology examination. The right inferior pulmonary vein was dissected free and left intact to prevent lobar congestion. The authors identified the right lower lobe segmental pulmonary arteries. They were able to identify the middle lobe artery, as well as two large basilar segmental branches. The middle lobe branch appeared to be coming off the basilar segmental branches. Dissection and stapling of the individual basilar branches was performed. After taking a branch of the pulmonary artery, the inferior vein was divided. The remaining basilar branches were divided. The fissure was opened further posteriorly to expose the superior segmental artery. After adequate exposure, the superior segmental artery was stapled and divided. The anterior fissure was opened to identify the bronchus. The bronchus was dissected clearly to identify the RC2 bronchus and hilar nodes in this area that were independently removed when necessary. The lower lobe was rotated and the bronchus was isolated. The right lung was inflated to ensure that the right middle lobe bronchus was preserved. The bronchus was divided and the posterior parenchymal fissure was divided to complete the lobectomy. The authors performed lymphadenectomy in stations 10R, 7, and 4R. These nodes were sent for frozen pathology. Using an endoscopic specimen bag, the right lower lobe was removed through the subxiphoid incision. The authors have found that this allows for the removal of bigger specimens and patients appear to have less postoperative pain. Intercostal nerve blocks were then performed for postoperative pain control using liposomal bupivacaine. The patient tolerated the procedure well.

The final pathology from the surgical specimen was consistent with metastatic melanoma forming a 17 by 15 by 13 mm nodule in the right lower lobe. Molecular markers were consistent with this diagnosis. All mediastinal and hilar lymph nodes were negative for metastasis.

The patient tolerated the procedure well and was discharged on postoperative day three after an additional day of monitoring. He was seen by medical oncology for further staging showing no evidence of disease. He was started on nivolumab for treatment of metastatic melanoma.

In conclusion, this was the first ever all robotic procedure of this type to be performed by the same team. The all-robotic component of this patient's care is technologically novel, but there are broader implications. This patient stated he felt more comfortable going forward with surgery knowing that malignancy had been confirmed on diagnosis. This technology allowed streamlined diagnosis, staging, and treatment. Because of the ability to reach very small peripheral nodules with this technology safely, there is the possibility of future endoscopic treatments alone. Additionally, adequate tissue can be obtained where staining and targeted therapy is useful. And finally, these techniques spare costly surgical resources for biopsies and staging, while still promoting the progression of minimally invasive approaches for lung cancer diagnosis, staging, and treatment.

Reference

Fielding DIK, Bashirzadeh F, Son JH, Todman M, Chin A, Steinke K, et al. First human use of a new robotic-assisted fiber optic sensing navigation system for small peripheral pulmonary nodules. Respiration. 2019;98(2):142-150. Epub 2019 Jul 26.