The Chinese University of Hong Kong (CUHK)’s Faculty of Medicine (CU Medicine) is currently in a leading position in the world to conduct the first robot-assisted bronchoscopic microwave ablation of lung metastases.¹ As of October 2022, the procedure has been successful in treating the 6 lung metastases of 3 patients bilaterally, and it is currently in the process of preparing a clinical trial that aims to enroll up to 145 patients worldwide.¹

Lungs are among the most common sites of metastases, especially from primary cancers of the head and neck, breast and of the gastrointestinal (GI) system, via hematogenous spread.^2,3 Depending on the site, lung metastases may be surgically unresectable and will have to rely on other treatment modalities, such as chemotherapy, radiotherapy, and ablation therapy.⁴ Ablation therapy may include radiofrequency ablation and other novel options include immunotherapies.^5,6 A transbronchial microwave ablation of lung metastases is a novel, non-invasive treatment method that is lung parenchymal sparing.¹ The microwave and heat from the ablation are able to effectively kill cancer cells at a temperature higher than 60°C, providing patients a treatment option with minimal pain and blood loss, and without sacrificing any healthy lung tissue.¹

Dr. Lau, Wing-Hung Rainbow, Clinical Assistant Professor (honorary) of the Division of Cardiothoracic Surgery, from the Department of Surgery at the CU Medicine highlighted the functionality of the advanced robotic mechanism.¹ The robot-assisted bronchoscopic system improves navigational accuracy to lesions in the lung and stability during the procedure by utilizing real-time optical imaging with electromagnetic positioning that allows the operator to navigate the intricate pulmonary airways.¹ The procedure is undertaken with a remote console that controls the robotic arms and bronchoscope accurately to allow the device to negotiate accurately into the lung parenchyma towards the targeted site.¹ The modern robotic mechanism in the bronchoscope is able to maintain stability as the microwave ablation catheter performs its task.¹ This allows the ablation process to be accomplished accurately and efficiently.¹

Prof. Ng, Sze-Hang Calvin from the Division of Cardiothoracic Surgery, the Department of Surgery at the CU Medicine further outlined the benefits of accurate bronchoscopic navigation and transbronchial microwave ablation, which allow a non-invasive treatment for lung metastases.¹ This is in contrast to the conventional surgical resection in patients who have multiple bilateral lung metastases, which involves surgical incisions bilaterally with the removal of lung tissues that may cause significant harm to the lung function of patients, while potentially delaying chemotherapy due to the recovery interval post-operation.¹

CU Medicine has paved the way for the usage of navigational bronchoscopy that allows us to gain access and deliver diagnostics and therapeutics to peripherally located lung tumors.¹ The conventional usage of bronchoscopic ablation includes techniques such as laser, electrocautery and cryotherapy, using flexible or rigid bronchoscopy, depending on the location of the lesion, whether it is peripheral or central airway obstructing.⁷ However, the novel usage of robotic bronchoscopic microwave ablation is able to treat metastases without any incision or resection of the lung, thus rendering no adverse effect (AE) on the lung function and quality of life (QoL) of patients.¹ Prof. Ng furthered that the research team is preparing to conduct trials on the robot-assisted bronchoscopic microwave ablation for patients with primary lung cancers towards the end of 2023.¹