Preoperative radiotherapy and/or chemotherapy of lung cancer in patients with locally advanced disease is an option in multimodal treatment. Sleeve lobectomy has an important part in decreasing complications and sparing lung function. We present our experience in a large cohort of patients after sleeve lobectomy with or without neoadjuvant treatment and standardized assessment of bronchial anastomotic healing. The data used for this study were collected ina prospective database in our hospital. Anastomotic healing was documented by bronchoscopy on the seventh postoperative day and thereafter only when necessary, using a standardized scoring system. From 2006 to 2017, we performed 501 sleeve lobectomies representing 19%of all lung cancer resections. A total of 365 ofpatients had no preoperative treatment (73%), 41 had neoadjuvant chemotherapy (8%), and 95 had radiochemotherapy (19%). Using our scoring system of the bronchial anastomosis from 1 (excellent) to 5 (insufficient), we found the anastomosis was worse than grade 2 after no treatment, chemotherapy, or radiochemotherapy in 17%, 10%, and 30%, respectively (P= .002). The rate of anastomotic insufficiency was equally low after no pretreatment and chemotherapy (2.7% and 2.4%) and rose to 10.4% after radiotherapy (P= .002). Similarly, the risk for pulmonary complications was higher after radiochemotherapy (39%) compared with no pretreatment (29%) or chemotherapy (27%), respectively (P= .382). Neoadjuvant radiotherapy is associated with worse wound healing of the anastomosis after sleeve lobectomy in lung cancer. There seems to be a higher risk for anastomotic insufficiency and complications.