A newly developed surgeon-controlled suction device in robotic-assisted thoracoscopic surgery.

INTRODUCTION: Assistant surgeons usually clean the surgical field with a suction cannula in robotic-assisted surgery. This manipulation requires skill and experience to avoid interfering with the operation of the console surgeon. Recently, we created a new suction device that a console surgeon can manipulate with the robotic arms. MATERIALS AND SURGICAL TECHNIQUE: A small metal suction tip with as a lumen and small side pores for suction and can be connected to a silicone tube connected to wall suction. The tip of the silicone tube can be grasped with robotic forceps and used for organ retraction as well as suction. The suction device has been used in eight lung lobectomy cases and four lung segmentectomy cases to date. There were no major difficulties related to the new suction device except for metal tip disconnection and blood clots clogging. DISCUSSION: Our newly developed surgeon-controlled suction device is inexpensive, easy to handle, and useful for suction, blunt dissection, and organ retraction in robotic-assisted thoracoscopic surgery, especially when performing lymph node dissection.

Mechanism of action of DSP-7888 (adegramotide/nelatimotide) Emulsion, a peptide-based therapeutic cancer vaccine with the potential to turn up the heat on non-immunoreactive tumors

Background Wilms’ tumor 1 (WT1) is highly expressed in various solid tumors and hematologic malignancies. DSP-7888 (adegramotide/nelatimotide) Emulsion is an investigational therapeutic cancer vaccine comprising three synthetic epitopes derived from WT1. We evaluated the mechanism of action of DSP-7888 Emulsion, which is hypothesized to induce WT1-specific cytotoxic T lymphocytes (CTLs) and helper T lymphocytes (HTLs). Methods The ability of nelatimotide and adegramotide to induce WT1-specific CD8+ T cells and CD4+ T cells was assessed in human peripheral blood mononuclear cells (PBMCs). The ability of DSP-7888 Emulsion to induce WT1-specific CTLs in vivo was assessed using human leukocyte antigen-I (HLA-I) transgenic mice. To assess how adegramotide, the helper peptide in DSP-7888 Emulsion, enhances WT1-specific CTLs, HLA-I transgenic mice were administered DSP-7888 or nelatimotide-only Emulsion. Interferon-gamma secretion under antigen stimulation by splenocytes co-cultured with or without tumor cells was then quantified. The effects of combination treatment with DSP-7888 Emulsion and an anti–programmed cell death protein 1 (PD-1) antibody on tumor volume and the frequency of tumor-infiltrating WT1-specific T cells were assessed in HLA-I transgenic mice implanted with WT1 antigen-positive tumors. Result The peptides in DSP-7888 Emulsion were shown to induce WT1-specific CTLs and HTLs in both human PBMCs and HLA-I transgenic mice. Unlike splenocytes from nelatimotide-only Emulsion-treated mice, splenocytes from DSP-7888 Emulsion-treated mice exhibited high levels of interferon-gamma secretion, including when co-cultured with tumor cells (AU)

Association between oxygen consumption and stepping exercise standardized with a triaxial accelerometer.

OBJECTIVE: According to the current American College of Chest Physicians (ACCP) guideline, a cardiopulmonary exercise test (CPET) is indicated in patients with lung cancer being considered for lung surgery. The measurement of maximum oxygen consumption ([Formula: see text] max) is not sufficiently prevalent because it requires special technical equipment. Considering that stepping is a simple and common exercise, we aimed to establish a simple and reproducible test with standardization of exercise intensity using a triaxial accelerometer. METHODS: Twenty healthy volunteers (10 male, 10 female) were included in the study. The subjects were obliged to step on the same spot at the rate of 80 and 110 counts for 1 min each and then step as quickly as possible for the last minute. Oxygen consumption ([Formula: see text]) (mL/kg/min) for every breath was continuously measured during the exercise. A triaxial accelerometer was attached to the hip of test subjects whereby metabolic equivalents (METs) at each test level were measured. RESULTS: The mean age of the study subjects was 42.9 ± 11.4 (mean ± SD). The mean value of [Formula: see text] at each level increased linearly along with the stepping level in each individual but varied among subjects. Using METs instead of step counts minimized the difference in regression lines among subjects. A receiver operating characteristic analysis revealed the possibility of [Formula: see text] prediction for the critical values of 10 and 20 mL/kg/min using METs. CONCLUSION: A simple and reproducible stepping test was suggested as applicable to standardizing the intensity of exercise using a triaxial accelerometer.

Mechanism of action of DSP-7888 (adegramotide/nelatimotide) Emulsion, a peptide-based therapeutic cancer vaccine with the potential to turn up the heat on non-immunoreactive tumors.

BACKGROUND: Wilms' tumor 1 (WT1) is highly expressed in various solid tumors and hematologic malignancies. DSP-7888 (adegramotide/nelatimotide) Emulsion is an investigational therapeutic cancer vaccine comprising three synthetic epitopes derived from WT1. We evaluated the mechanism of action of DSP-7888 Emulsion, which is hypothesized to induce WT1-specific cytotoxic T lymphocytes (CTLs) and helper T lymphocytes (HTLs). METHODS: The ability of nelatimotide and adegramotide to induce WT1-specific CD8+ T cells and CD4+ T cells was assessed in human peripheral blood mononuclear cells (PBMCs). The ability of DSP-7888 Emulsion to induce WT1-specific CTLs in vivo was assessed using human leukocyte antigen-I (HLA-I) transgenic mice. To assess how adegramotide, the helper peptide in DSP-7888 Emulsion, enhances WT1-specific CTLs, HLA-I transgenic mice were administered DSP-7888 or nelatimotide-only Emulsion. Interferon-gamma secretion under antigen stimulation by splenocytes co-cultured with or without tumor cells was then quantified. The effects of combination treatment with DSP-7888 Emulsion and an anti-programmed cell death protein 1 (PD-1) antibody on tumor volume and the frequency of tumor-infiltrating WT1-specific T cells were assessed in HLA-I transgenic mice implanted with WT1 antigen-positive tumors. RESULTS: The peptides in DSP-7888 Emulsion were shown to induce WT1-specific CTLs and HTLs in both human PBMCs and HLA-I transgenic mice. Unlike splenocytes from nelatimotide-only Emulsion-treated mice, splenocytes from DSP-7888 Emulsion-treated mice exhibited high levels of interferon-gamma secretion, including when co-cultured with tumor cells; interferon-gamma secretion was further enhanced by concomitant treatment with anti-PD-1. HLA-I transgenic mice administered DSP-7888 Emulsion plus anti-PD-1 experienced significantly greater reductions in tumor size than mice treated with either agent alone. This reduction in tumor volume was accompanied by increased numbers of tumor-infiltrating WT1-specific CTLs. CONCLUSIONS: DSP-7888 Emulsion can promote both cytotoxic and helper T-cell-mediated immune responses against WT1-positive tumors. Adegramotide enhances CTL numbers, and the CTLs induced by treatment with both nelatimotide and adegramotide are capable of functioning within the immunosuppressive tumor microenvironment. The ability of anti-PD-1 to enhance the antitumor activity of DSP-7888 Emulsion in mice implanted with WT1-positive tumors suggests the potential for synergy.

Thoracic composite hemangioendothelioma with neuroendocrine marker expression.

BACKGROUND: Composite hemangioendothelioma is an extraordinarily rare form of vascular neoplasm which develops predominantly in the skins and soft tissues of the adults. Neuroendocrine marker expression in composite hemangioendothelioma is considered as specifically relevant to the more aggressive behavior. CASE PRESENTATION: The patient was a 71-year-old man complaining continuous back pain. Computed tomography (CT) showed that 10 cm of contrast-enhanced soft tissue mass was occurring on the right posterior chest wall and developing adjacent to the spinal canal. Via the laminectomy, the tumor end was identified and separated from the dura mater. Then, via the posterolateral thoracotomy, the en bloc resection was achieved by separating the tumor from the diaphragm and vertebras. Histologic examination showed a complex combination of epithelioid and retiform hemangioendothelioma areas which were positive for anti-synaptophysin staining. At 12-month follow-up, there were no signs of tumor recurrence on CT, and the patient had no symptom. CONCLUSIONS: We achieved the complete resection of a huge thoracic neuroendocrine composite hemangioendothelioma developing adjacent to the spinal canal. The combination of the posterior lumbar laminectomy and the following posterior thoracotomy is a viable approach to radically resect a thoracic neuroendocrine composite hemangioendothelioma involving chest wall.

Thoracoscopic rib resection and reconstruction of chest wall: Our clinical experience.

Chest wall resection is traditionally performed via open thoracotomy, a procedure that increases surgical morbidity and reduces postoperative quality of life. Conversely, thoracoscopic chest wall resection may minimize invasiveness but the optimal procedure remains uncertain. We previously reported rib resection using a pneumatic high-speed power drill during video-assisted thoracoscopic surgery for selected lung cancer patients. In this report, we present two cases of chest wall tumor resected using the drill via the thoracoscopic approach. We also report thoracoscopic chest wall reconstruction in one patient using a patch sheet.

Clinical Experience of Thoracoscopic Sleeve Lobectomy Using a Novel Needle Holder.

Thoracoscopic bronchoplasty requires high technique to control stitching during bronchial reconstruction. Improved quality of suturing instrument may contribute to overcome this difficulty of bronchial anastomosis. Recently, a unique and expected articulated instrument for suturing has been launched on endoscopic surgery. We have successfully performed two cases of thoracoscopic sleeve lobectomy using this instrument.

Association between values of preoperative 6-min walk test and surgical outcomes in lung cancer patients with decreased predicted postoperative pulmonary function.

OBJECTIVE: We retrospectively investigated the possibility that the 6-min walk test (6MWT) could predict surgical outcomes in lung cancer patients with decreased predicted postoperative (ppo) lung function. METHODS: Patients were enrolled based on their preoperative spirometry: <60% of the ppo forced expiratory volume in 1 s (FEV1.0) or < 60% of the ppo lung carbon monoxide diffusion capacity (DLco). Morbidity, oxygen inhalation required > 10 days, home oxygen therapy (HOT) requirement, unexpected readmission within 90 days, and 90-day mortality were included as surgical outcomes. The correlations with walking distance and the minimum SpO2 (SpO2min) and maximum decrease in SpO2 (ΔSpO2) during the 6MWT were analyzed using logistic regression analysis, adjusting for age, sex, and surgical procedure. RESULTS: Altogether, 121 patients were analyzed. Logistic regression analysis revealed that higher ΔSpO2 and lower SpO2min were significantly correlated with a higher risk of prolonged need for oxygen inhalation and HOT, surgical morbidity, and 90-day mortality. Cut-off values of > 4% for ΔSpO2 were significant for prolonged oxygen inhalation and surgical morbidity. Cut-off values of < 89-91% for SpO2min were also significant for the need for prolonged oxygen inhalation, surgical morbidity, and HOT requirement. There were no significant correlations between walking distance and each surgical outcome. CONCLUSIONS: Oxygen desaturation during 6MWT was a good predictor for poor surgical outcomes in lung cancer patients with decreased ppo pulmonary function.

Thoracoscopic partial resection without using a stapler. (complete republication).

Thoracoscopic partial pulmonary resection for small peripheral nodules without using a stapler has been introduced to our hospital. After partial resection was performed with electrocautery, two different methods of surface sealing were used: a coagulation method (C method) with Soft Coagulation alone, and a coagulation-suturing method (CS method) with Soft Coagulation combined with continuous suturing. The clinical outcomes of the two methods were retrospectively compared in this study. The C method was used in 19 lesions of 18 cases, and the CS method was used in 20 lesions of 19 cases. Primary lung cancer was the most frequent diagnosis (22 lesions of 21 cases). There were no differences between the two groups in the size and depth of the lesions. Operative time was longer with the CS method than with the C method. Postoperative air leakage was a complication in 4 cases with the C method, and one of them required re-do surgery, whereas only one case with the CS method had temporary air leakage. Postoperative computed tomography showed cavitation in 3 C method cases and 5 CS method cases, all without related symptoms. There were no local recurrences at resected sites. In conclusion, the C method was technically easy to perform, but air leakage may be prolonged after surgery. The CS method may have the advantage of causing less air leakage than the C method, but mastering the technique is important to shorten operative time.

Rib resection using a pneumatic high-speed power drill system for lung cancer with chest wall invasion: our clinical experience.

Rib resection for chest wall tumors, including lung cancer with chest wall invasion, is usually performed through open thoracotomy. Resection of part of the external rib cage requires an elongated or additional incision depending on the location and extension of the tumor, eventually becoming more invasive to patients. We recently introduced a technique of rib resection using a pneumatic high-speed power drill system known as "air tome". This novel technique is easy to perform through a small incision or even via video-assisted thoracoscopic surgery (VATS) in selected patients. We present our clinical experience and discuss the usefulness of this technique for rib resection in patients with lung cancer and chest wall invasion.

Prognostic value of body mass index and change in body weight in postoperative outcomes of lung cancer surgery.

OBJECTIVES: Nutritional status is associated with an effect on oncological outcomes. However, the effect of nutritional status on postoperative survival in lung cancer has not been well studied. We retrospectively analysed and evaluated the effect of preoperative body mass index (BMI) and changes in body weight on postoperative outcomes of lung cancer surgery. METHODS: A total of 1311 patients with non-small-cell lung cancer who underwent surgery between January 2001 and December 2011 were included in this study. Preoperative body weight at 4-12 weeks prior to surgery was obtained in 737 patients and the ratio of change in body weight was calculated. RESULTS: The patients were classified into four groups as follows: underweight (BMI < 18.5), normal weight (BMI from ≥18.5 to <25), overweight (BMI from ≥25 to <30) and obese (BMI ≥ 30). Postoperative survival curves of the BMI groups showed that the underweight group had a poorer prognosis than the other groups, especially for disease-free survival (DFS) (P = 0.03). Univariate and adjusted survival analyses using Cox's proportional hazards regression model showed that low BMI was a significantly poor prognostic factor in overall survival (OS) (P = 0.03 and P = 0.02, respectively) and DFS (P < 0.01 and P < 0.01, respectively). Among the BMI groups, the underweight group had a significant worse prognosis than the other groups for DFS in univariate and adjusted analyses (P = 0.04 and P < 0.01, respectively). With regard to changes in body weight, patients with a body weight loss of 3.7% or greater had a significantly poorer prognosis for OS and DFS in univariate analysis and for DFS in adjusted analyses compared with the other patients. Regarding short-term outcomes, the weight loss group had a significantly longer postoperative hospital stay than the non-weight loss group (P = 0.02) and postoperative 90-day mortality was significantly lower in the normal weight group than in the underweight group (P = 0.03). CONCLUSIONS: Low BMI and significant body weight loss before surgery have a negative effect on surgical outcomes for patients with non-small-cell lung cancer.

Fibrocyte-like cells mediate acquired resistance to anti-angiogenic therapy with bevacizumab.

Bevacizumab exerts anti-angiogenic effects in cancer patients by inhibiting vascular endothelial growth factor (VEGF). However, its use is still limited due to the development of resistance to the treatment. Such resistance can be regulated by various factors, although the underlying mechanisms remain incompletely understood. Here we show that bone marrow-derived fibrocyte-like cells, defined as alpha-1 type I collagen-positive and CXCR4-positive cells, contribute to the acquired resistance to bevacizumab. In mouse models of malignant pleural mesothelioma and lung cancer, fibrocyte-like cells mediate the resistance to bevacizumab as the main producer of fibroblast growth factor 2. In clinical specimens of lung cancer, the number of fibrocyte-like cells is significantly increased in bevacizumab-treated tumours, and correlates with the number of treatment cycles, as well as CD31-positive vessels. Our results identify fibrocyte-like cells as a promising cell biomarker and a potential therapeutic target to overcome resistance to anti-VEGF therapy.

Preoperative Evaluation of the Right Upper Lobe Pulmonary Artery by 3D-CT Pulmonary Angiography vs. Thin-Section Multiplanar Reconstruction Images Obtained by Contrast-Enhanced Multidetector-Row CT.

We compared the effectiveness of 3-dimensional computed tomography pulmonary angiography (3D-CTPA) and thin-section multiplanar reconstruction (MPR) images obtained using contrast-enhanced multidetector row CT (MDCT), in the evaluation of pulmonary artery (PA) branches of the right upper lobe. We studied 127 patients suspected of having lung cancer of the right upper lobe who underwent contrast-enhanced MDCT scans and a right upper lobectomy. We compared the intraoperative findings of the PA branches of the right upper lobe obtained with 3D-CTPA and thin-section MPR images. In 125 (97.7%) patients, one or more PA branches arose from arteries other than the superior trunk. Among 10 (7.9%) patients, a PA branch arose from the middle lobe in one patient and from the superior segment of the lower lobe in the other 9 patients. According to the intraoperative findings, 97.2% and 99.7% of the PA branches were identified by 3D-CTPA and thin-section MPR images, respectively (p ＜ 0.03). The single branch missed by both imaging modalities was 1.0mm in dia. The 8 branches missed only by 3D-CTPA were ＜ 1.4mm in dia. Both the 3D-CTPA and thin-section MPR images provided precise preoperative information regarding PA branches of the right upper lobe. However, the thin-section MPR images appeared to contribute more to the evaluation of smaller PA branches.

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.

Novel therapeutic approach for pulmonary emphysema using gelatin microspheres releasing basic fibroblast growth factor in a canine model.

PURPOSES: The prognosis of patients with emphysema is poor as there is no truly effective treatment. Our previous study showed that the alveolar space was smaller and the microvessel density was higher in a canine emphysema model after the intrapulmonary arterial administration of gelatin microspheres slowly releasing basic fibroblast growth factor (bFGF-GMS). In the present study, we evaluated the functional effect of injecting bFGF-GMS via the pulmonary artery in this canine pulmonary emphysema model. METHODS: Using the porcine pancreatic elastase (PPE)-induced total emphysema model, we approximated the value of lung compliance with a Power Lab System, and performed blood gas analysis in a control group, a total emphysema group, and a bFGF group in which bFGF-GMS were injected toward the whole pulmonary artery via the femoral vein. Each group comprised five dogs. RESULTS: Lung compliance was higher in the total emphysema group than in the control group (p = 0.031), and the bFGF group showed no significant improvement of lung compliance vs. the total emphysema group (p = 0.112). PaO2 (partial pressure of oxygen in arterial blood) was improved by administering bFGF-GMS in the total emphysema model (p = 0.027). CONCLUSION: In the canine total emphysema model, blood gas parameters were improved by the whole pulmonary arterial administration of bFGF-GMS. This method has the potential to be an effective novel therapy for pulmonary emphysema.

Chemotherapy followed by surgery on the basis of biomarker examination for patients with advanced non-small cell lung cancer.

BACKGROUND/AIM: We have previously reported that low expression of excision repair cross-complementing-1 (ERCC1), class III ß-tubulin (tubulin), thymidylate synthase (TYMS) and ribonucleotide reductase-M1 (RRM1) is indicative of a favorable prognosis in patients with c-N2,3 non-small cell lung cancer (NSCLC) treated with surgery after induction chemoradiotherapy. In the present study, we prospectively explored the tailor-made treatment menu for induction chemotherapy according to the status of biomarkers, and evaluated the biomarker status pre- and post-chemotherapy. PATIENTS AND METHODS: Twenty-five patients with pathologically-proven NSCLC who were not appropriate candidates for initial surgery were enrolled (October 2010 to June 2012, stage IIIA/B/IV1a/1b;14/5/2/4 respectively). Immunohistochemistry was performed to evaluate intratumoral expression of biomarkers. Epidermal growth factor receptor (EGFR) mutation was evaluated by direct sequencing. Two to four cycles of chemotherapy were performed with or without concurrent radiation (50 Gy). RESULTS: Docetaxel (n=12), pemetrexed (n=4), S-1 (n=4), docetaxel-plus-bevacizumab (n=3), and pemetrexed-plus-bevacizumab (n=2), in combination with platinum were selected for the therapeutic regimen. Twenty-one (84.0%) patients exhibited good partial response, and underwent complete resection without major morbidity or mortality. Of these 21 patients, four achieved a pathologically-complete response (PCR), and 10 achieved a major pathological response. The 3-year overall survival rate was 58.7% for the 25 patients overall, and the 2-year overall survival rate was 73.6% for patients who underwent surgery. Among the 17 patients who underwent resection (except for four with PCR), the status of ERCC1, tubulin, TYMS, RRM1 and EGFR changed markedly after chemotherapy in six patients, eleven patients, eight patients, nine patients and one patient, respectively. CONCLUSION: Chemotherapy followed by surgery on the basis of biomarker examination is a challenging approach for patients with advanced NSCLC who otherwise have poor outcomes. Post-chemotherapy biomarker status changed markedly in many cases.

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

BACKGROUND: The 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. METHODS: Patients 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. RESULTS: Of 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). CONCLUSIONS: The existence of CTCs in pulmonary venous blood reflects pathological non-CR, and therapeutic pathological response may be predicted by pvCTC measurement.

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.

New clinically applicable method for visualizing adjacent lung segments using an infrared thoracoscopy system.

OBJECTIVE: Our objective was to attempt a clinical trial of segmentectomy using the infrared thoracoscopy system after intravenous injection of indocyanine green. PATIENTS AND METHODS: A total of 8 patients with lung lesions were investigated (5 with primary lung cancer, 2 with metastatic lung tumor, and 1 with inflammatory change). All were scheduled to undergo segmentectomy and had been confirmed to have no allergy to iodine or indocyanine green. Informed consent was obtained from all patients. We identified the dominant pulmonary artery supplying the target segment using reconstructed computed tomography images. The dominant pulmonary artery of the target segment was ligated, and after we had observed the lung using the infrared thoracoscopy system after intravenous injection of indocyanine green (3.0 mg/kg), and marked the white-to-blue transitional zone by electrocautery, we performed segmentectomy. RESULTS: Average operation time was 150 ± 62.1 minutes, and bleeding volume was 68.8 ± 30.5 mL. Under infrared thoracoscopy, the area with a normal blood supply became stained blue 13 seconds after injection of indocyanine green. Maximum staining intensity was attained 28 seconds after dye injection, and the observation duration was 3.5 minutes. A well-defined color zonation was observed in all patients. We had enough time to mark it. No complications attributable to infrared thoracoscopy after intravenous injection of indocyanine green were encountered. CONCLUSIONS: Infrared thoracoscopy with indocyanine green makes it possible to identify the target lung segment easily and quickly without the need for inflation. This method will be especially useful for cases associated with severe emphysema or when surgery offers a limited view, as is the case with video-assisted thoracic surgery.