Yoshitaka Kasai

Clinical trial of new methods for identifying lung intersegmental borders using infrared thoracoscopy with indocyanine green: comparative analysis of 2- and 1-wavelength methods

OBJECTIVES Infrared thoracoscopy is a new method of identifying lung intersegmental borders. This study compared the efficacy of 2- and 1-wavelength infrared thoracoscopy. METHODS A total of 30 consecutive patients who underwent segmentectomy were evaluated by these methods (2-wavelength method, 10 patients; 1-wavelength method, 20 patients). We ligated the dominant pulmonary artery and then observed the lung using an infrared thoracoscope after indocyanine green (ICG) intravenous injection. The 2-wavelength infrared thoracoscope irradiation and detection were conducted at 940 and 805 nm, respectively, and the images were projected based on the difference of the two reflected wavelengths. ICG absorbs 805 nm wavelength light, and the ICG distribution area appears blue against a white background. On the other hand, the 1-wavelength infrared thoracoscope irradiation and detection were conducted at 780 and 830 nm, respectively. The area stained with ICG shows fluorescence. RESULTS In the 2-wavelength method, 3.0 mg/kg of ICG was administered, and a well-defined white-to-blue border was observed in 9 of 10 patients. The staining duration was 220 (interquartile range, 187-251) s. In the 1-wavelength method, 0.5 mg/kg of ICG was administered, and a well-defined border between areas with or without fluorescence was observed in 19 of 20 patients. The staining duration was 370 (interquartile range, 296-440) s, which was significantly longer than the staining duration with the 2-wavelength method (P = 0.0001). CONCLUSIONS Infrared thoracoscopy is useful for detection of intersegmental borders. The dose of ICG for the 1-wavelength method was less than that for 2-wavelength method, and the duration of staining was longer.

Clinical trial of video-assisted thoracoscopic segmentectomy using infrared thoracoscopy with indocyanine green.

OBJECTIVES The maintenance of a good surgical view is mandatory in video-assisted thoracoscopic surgery (VATS). For routine segmentectomy, it is necessary to re-inflate the lung in order to identify the intersegmental line. However, such re-inflation can occasionally obstruct the surgical view. Infrared thoracoscopy (IRT) with indocyanine green (ICG) can reveal the intersegmental line based on blood flow differences, without the need for lung re-inflation. The purpose of this study was to confirm the usefulness of IRT with ICG for VATS. METHODS Between October 2008 and September 2011, 44 consecutive patients underwent segmentectomy at our institution. In 13 patients, VATS segmentectomy using IRT with ICG was employed. Informed consent was obtained from all patients. Computed tomography was performed to identify the dominant pulmonary artery supplying the target segment. The operations were performed using two ports and one mini-thoracotomy (3-6 cm). The dominant arteries were interrupted, and the intersegmental line was identified using IRT with ICG. RESULTS Identification of the intersegmental line was possible in 11 (84.6%) of the 13 patients. The average age was 70 years, and 6 of the patients were male. The mean operation time was 191 min, and the mean bleeding volume was 64 ml. The operation time and bleeding volume were similar to the values in the other 31 patients who underwent thoracotomy (167 min/115 ml, P = 0.212/0.361, respectively). No complications attributable to IRT with ICG were observed. CONCLUSIONS VATS segmentectomy using IRT with ICG allows the maintenance of a clear surgical view and identification of the intersegmental line in a high proportion of cases. Therefore, we consider this method to be useful for minimally invasive thoracic surgery.

Pulmonary rehabilitation during induction chemoradiotherapy for lung cancer improves pulmonary function

OBJECTIVE Chemoradiotherapy for non-small cell lung cancer can impair pulmonary function, particularly when it is followed by surgery. This study aimed to document the changes in respiratory function as a result of a perioperative intensive pulmonary rehabilitation program in patients with non-small cell lung cancer who underwent induction chemoradiotherapy. METHODS A total of 82 consecutive patients underwent pulmonary resection after undergoing induction chemoradiotherapy. A pulmonary rehabilitation program was started at the same time as the induction chemoradiotherapy. Standard respiratory function tests were performed before and after induction chemoradiotherapy. Treatment-related mortality and the incidence of postoperative respiratory complications were investigated. The Wilcoxon signed-rank test was used to analyze the differences in spirometric changes. RESULTS All patients underwent a pulmonary rehabilitation program for an average of 10 weeks. Significant increases were observed in forced vital capacity (+6.4%, P = .0096) and forced expiratory volume in 1 second (+10.4%, P < .0001). Diffusing capacity of the lung for carbon monoxide decreased (-14.0%, P < .0001). Patients with respiratory impairment (forced vital capacity <80% predicted or forced expiratory volume in 1 second/forced vital capacity <70%) showed significant improvements in forced vital capacity (+13.9%, P = .0025) and forced expiratory volume in 1 second (+22.5%, P < .0001). Significant increases were observed in forced vital capacity (+7.0%, P = .0042) and forced expiratory volume in 1 second (+10.8%, P = .0001) in patients with a smoking history. There was no mortality, and postoperative respiratory morbidity was 6.1%. CONCLUSIONS A pulmonary rehabilitation program for patients with non-small cell lung cancer undergoing induction chemoradiotherapy seems to improve respiratory function. It is particularly recommended for smokers and patients with respiratory impairment.

Innovative method using circulating tumor cells for prediction of the effects of induction therapy on locally advanced non-small cell lung cancer

BackgroundThe existence of circulating tumor cells (CTCs) in patients with lung cancer has been reported. The purpose of this study was to assess whether CTCs are predictive of the pathological effects of induction chemoradiotherapy for patients with non-small cell lung cancer.MethodsPatients who underwent induction chemoradiotherapy followed by surgery were compared with those who underwent surgery alone. Peripheral and pulmonary venous blood samples from the involved lobe were collected intraoperatively, and the number of CTCs was counted using the CellSearch™ system, an epithelial cell adhesion molecule-based immunomagnetic technique.ResultsOf the 9 patients who underwent induction therapy, 4 achieved pathological CR, 4 achieved major response, and 1 achieved minor response. All patients who underwent induction therapy and surgery alone were negative for CTCs in peripheral blood. In the induction therapy group, 4 patients showing pathological CR were negative for CTCs in pulmonary venous blood (pvCTCs) and 5 showing major/minor response were positive (mean, 57.8 cells). The numbers of CTCs in patients showing major/minor response were significantly higher than those in patients showing pathological CR (p = 0.012, Mann–Whitney U test). All 6 patients undergoing surgery alone were positive for pvCTCs (mean, 207.5 cells), showing a significant difference from those undergoing induction therapy (p = 0.038).ConclusionsThe existence of CTCs in pulmonary venous blood reflects pathological non-CR, and therapeutic pathological response may be predicted by pvCTC measurement.

Three-dimensional computed tomography reveals anatomical variant of meandering pulmonary vein

Figure 2: 3D-CT demonstrated a meandering pulmonary vein forming a loop, and draining into the superior pulmonary vein. It resembles a scimitar vein, but ultimately drains normally into the left atrium. The inferior pulmonary vein appeared normal. SPECT/CT demonstrated a defect in the S3/S4 area of the left lung. The area of the defect corresponded to the loop formed by the meandering pulmonary vein. It was suspected that within the loop no blood was supplied by the pulmonary circulation.