Recent Advances in Bronchoscopic Treatment of Peripheral Lung Cancers

Abstract

The detection of peripheral lung nodules is increasing because of the expanded use of CT imaging and implementation of lung cancer screening recommendations. Although surgical resection of malignant nodules remains the treatment modality of choice at present, many patients are not surgical candidates, thus prompting the need for other therapeutic options. Stereotactic body radiotherapy (SBRT) and percutaneous thermal ablation are emerging as viable alternatives to surgical resection. For safety, efficacy, and cost-effectiveness purposes, however, alternative bronchoscopic methods for treatment of peripheral lung cancer are currently under active exploration. We searched the Cochrane Library and MEDLINE from 1990 to 2015 to provide the most comprehensive review of bronchoscopic treatment of malignant lung nodules. We used the following search terms: bronchoscopy, lung nodule, peripheral lung lesion, and bronchoscopic treatment. We focused on peripheral pulmonary nodules that are confirmed or highly likely to be malignant. Seventy-one articles were included in this narrative review. We have provided an overview of advanced bronchoscopic modalities that have been used or are under active investigation for definitive treatment of malignant pulmonary nodules. We have concisely discussed the use of direct intratumoral chemotherapy or gene therapies, transbronchial brachytherapy, bronchoscopy-guided radiofrequency ablation (RFA), placement of markers to guide real time-radiation and surgery, cryotherapy, and photodynamic therapy. We have also briefly reported on emerging technologies such as vapor ablation of lung parenchyma for lung cancers. Advances in bronchoscopic therapy will bring additional treatment options to patients with peripheral lung malignancies, with putative advantages over other minimally invasive modalities.