title: Single-port video-assisted thoracic surgery for early lung cancer: initial experience in Japan.
abstract: BACKGROUND
  Single-port video-assisted thoracic surgery (SPVATS) emerged several years ago as a new, minimally invasive surgery for diseases in the field of respiratory surgery, and is increasingly becoming a subject of interest for some thoracic surgeons in Europe and Asia. However, the adoption rate of this procedure in the United States and Japan remains low. We herein reviewed our experience of SPVATS for early lung cancer in our center, and evaluated the safety and minimal invasiveness of this technique.
  
  
  METHODS
  We retrospectively analyzed patients who had undergone SPVATS for pathological stage I lung cancer in Nippon Medical School Chiba Hokusoh Hospital between September 2012 and October 2015. In SPVATS, an approximately 4-cm incision was made at the 4(th) or 5(th) intercostal space between the anterior and posterior axillary lines. A rib spreader was not used at the incision site, and surgical manipulation was performed very carefully in order to avoid contact between surgical instruments and the intercostal nerves. The same surgeon performed surgery on all patients, and analyzed laboratory data before and after surgery.
  
  
  RESULTS
  Eighty-four patients underwent anatomical lung resection for postoperative pathological stage I lung cancer. The mean wound length was 4.2 cm. Eighty-four patients underwent lobectomy and segmentectomy, respectively. The mean preoperative forced expiratory volume in 1 second (FEV1%) was 1.85%±0.36%. Our patients consisted of 49 men (58.3%) and 35 women (41.7%), with 64, 18, 1, and 1 having adenocarcinoma, squamous cell carcinoma, adenosquamous carcinoma, and small-cell lung cancer, respectively. The mean operative time was 175±21 min, operative blood loss 92±18 mL, and duration of drain placement 1.9±0.6 days. The duration of the postoperative hospital stay was 7.1±1.7 days, numeric rating scale (NRS) 1 week after surgery 2.8±0.6, and occurrence rate of allodynia 1 month after surgery 10.7%. No patient developed serious complications, and no deaths occurred within 30 days of surgery. Two patients (2.4%) were converted to open thoracotomy.
  
  
  CONCLUSIONS
  SPVATS is a safe and feasible technique, and is promising for next-generation thoracoscopic surgery. It may also reduce postoperative wound pain and contribute to improvements in the activities of daily living of patients.
authors.affiliation: 1 Division of Thoracic Surgery, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan ; 2 Division of Thoracic Surgery, Nippon Medical School, Tokyo, Japan.
authors.forename: Kyoji
authors.initials: K
authors.lastname: Hirai
authors.affiliation: 1 Division of Thoracic Surgery, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan ; 2 Division of Thoracic Surgery, Nippon Medical School, Tokyo, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Takeuchi
authors.affiliation: 1 Division of Thoracic Surgery, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan ; 2 Division of Thoracic Surgery, Nippon Medical School, Tokyo, Japan.
authors.forename: Jitsuo
authors.initials: J
authors.lastname: Usuda
keywords: Single-port video-assisted thoracic surgery (SPVATS); conventional VATS (c-VATS); minimal invasiveness