Pulmonary Laser Metastasectomy by 1318-nm Neodymium-Doped Yttrium-Aluminum Garnet Laser: A Retrospective Study About Laser Metastasectomy of the Lung.

BACKGROUND: The lungs are among the first organ affected by remote metastases from many primary tumors. The surgical resection of isolated pulmonary metastases represents an important and effective element of therapy. This is a retrospective study about our entire experience with pulmonary resection for metastatic cancer using 1318-nm neodymium-doped yttrium-aluminum garnet laser. METHOD: In this single-institution study, we retrospectively analyzed a group of 209 patients previously treated for primary malignant solid tumors. We excluded 103 patients. The number and location of lesions in the lungs was determined using chest computed tomography and positron emission tomography-computed tomography. Disseminated malignancy was excluded. All pulmonary laser resections are performed via an anteroaxillary muscle-sparing thoracotomy. All lesions were routinely removed by laser with a small (5-10 mm) margin of the healthy lung. Patients received systematic lymph node sampling with intraoperative smear cytology of sampled lymph nodes. RESULTS: Mortality at 2 years from the first surgery is around 20% (10% annually). This value increases to 45% in the third year. The estimated median survival for patients who underwent the first surgery is reported to be approximately 42 months. CONCLUSION: Our results show that laser resection of lung metastases can achieve good result, in terms of radical resection and survival, as conventional surgical metastasectomy. The great advantage is the possibility of limiting the damage to the lung. Stapler resection of a high number of metastases would mutilate the lung.

Video-Assisted Laser Resection of Lung Metastases-Feasibility of a New Surgical Technique.

Background Our pilot study describes our initial experience to do a laser resection of lung metastases under video-assisted thoracoscopic control via a minithoracotomy. With this approach, if needed, mediastinal lymphadenectomy is also possible. Methods In this study, 15 patients (11 men and 4 women, mean age: 60 years) with resectable lung metastases of different solid primary tumors (colorectal cancer in seven patients, melanoma in three patients, renal cell carcinoma in two patients, and one each with oropharyngeal cancer, breast cancer, and seminoma) were included. An anterior minithoracotomy incision (approximately 5-7 cm length) was created in the fifth intercostal space and a soft tissue retractor (Alexis Protector; Applied Medical) was positioned. Two additional working ports were inserted. The entire lung was palpated via the minithoracotomy. All detected lung metastases were removed under thoracoscopic control. Nonanatomic resections were performed using a diode-pumped neodymium-doped yttrium aluminium garnet laser (LIMAX120; KLS Martin GmbH & Co KG) with a laser power of 80 W in a noncontact modus. Deeper parenchymal lesions were sutured. Results A total of 29 lung metastases up to 30 mm in size were resected and all metastases diagnosed on preoperative imaging were detected. All diagnosed lung metastases were completely resected (R0). The median operation time was 102 (range: 85-120) minutes. Median blood loss was 47.6 mL and no postoperative complications occurred. Neither local recurrences nor new lung metastases were observed within 6 months after the procedures. Conclusion Video-assisted laser resection of lung metastases is safe, effective, and fulfills the requirements of modern lung metastases surgery.

Pulmonary metastasectomy: outcomes and issues according to the type of surgical resection.

According to a recent report by the Committee for Scientific Affairs of the Japanese Association for Thoracic Surgery, pulmonary metastasectomy accounted for as many as 10.2 % of all entry cases of general thoracic surgery, and its use is increasing year by year. Accordingly, many studies have examined the surgical procedures used during pulmonary metastasectomy for metastases from primary tumors affecting various organs as well as the outcomes of and indications for such procedures, but some problems remain. In this article, the following questions related to the surgical approach and the type of resection used during pulmonary metastasectomy are reviewed: (1) Wedge resection--what is a safe margin for preventing local recurrence? (2) What is the clinical significance of node sampling/dissection during pulmonary metastasectomy? and (3) When is segmentectomy necessary? In addition, we discuss: (4) open thoracotomy vs. video-assisted thoracoscopic surgery (VATS), (5) repeated metastasectomy for pulmonary metastases, (6) the surgical approach for bilateral pulmonary metastasectomy, (7) pneumonectomy, and (8) pulmonary metastasectomy combined with resection of the neighboring organs.

Comparison of local tissue damage: monopolar cutter versus Nd:YAG laser for lung parenchyma resection. An experimental study.

OBJECTIVES: Lung metastases are non-anatomically resected while sparing as much parenchyma as possible. For this purpose, a few surgeons use the Nd:YAG Laser LIMAX 120, whereas the majority of surgeons use a monopolar cutter like the MAXIUM. The aim of this experimental study was to investigate which instrument causes less lung-tissue damage at the same power output. METHODS: These experiments were conducted on left lungs (n = 6) taken from freshly slaughtered pigs. The laser and the monopolar cutter were fixed in a hydraulic mover. The laser was focused at a distance of 3 cm to the lung tissue and the monopolar cutter was fixed in pressure-free contact with the lung surface. Both instruments were manoeuvred at a speed of 5, 10 and 20 mm/s in a straight line at an output of 100 watts over the lung surface. The lung lesions that ensued were then examined macro- and microscopically. The same procedures were repeated at a distance of 1 cm creating parallel lesions in order to analyse the lung tissue in between the lesions for thermal damage. In addition, two implanted capsules in the lung tissue simulating a lung nodule were resected with either the laser or the monopolar cutter. The resection surfaces were then examined by magnetic resonance imaging and histology for tissue damage. Finally, we created a 2-cm wide mark on the lung surface to test the resection capacity of both instruments within 1 min. RESULTS: The laser created sharply delineated lesions with a vaporization and coagulation zone without thermal damage of the surrounding lung tissue. With lowering the working speed, each zone was extended. At a working speed of 10 mm/s, the mean vaporization depth using the laser was 1.74 ± 0.1 mm and the mean coagulation depth was 1.55 ± 0.09 mm. At the same working speed, the monopolar cutter demonstrated a greater cutting effect (mean vaporization depth 2.7 ± 0.11 mm; P < 0.001) without leaving much coagulation on the resection surface (mean coagulation depth 1.25 ± 0.1 mm; P = 0.002). In contrast to the laser, the monopolar cutter caused thermal damage of the adjacent lung tissue. The adjacent tissue injury was detected in histological examination as well as in the MRI findings. Adjacent lung tissue after lung metastasectomy using the monopolar cutter was hyper-intensive in T2-weighted MR imaging, indicating a severe tissue damage. No significant changes in signal intensity were observed in T2-weighted imaging of the adjacent lung tissue after using the laser for lung resection. One minute of laser applied at a 100-watt output penetrated a lung surface area of 3.8 ± 0.4 cm(2) compared with 4.8 ± 0.6 cm(2) of surface after application of the monopolar cutter (P = 0.001). CONCLUSIONS: The monopolar cutter possesses indeed a greater cutting capacity than the laser, but it also causes more adjacent tissue injury. Thus, laser resection might be preferred for lung metastasectomy.

Airtightness of lung parenchyma without a closing suture after atypical resection using the Nd:YAG Laser LIMAX 120.

OBJECTIVES: Lung metastases can be non-anatomically resected with a Nd:YAG Laser. It is recommended that the resected lung surface be sealed by slowly resorbable sutures. However, the lung tissue may be restricted by the sutures once it is re-ventilated. Thus, it was analysed whether the lung parenchyma is airtight after laser resection without suturing the defect. METHODS: The pulmonary artery of unimpaired paracardial lung lobes of freshly slaughtered pigs (mean weight 46 g) was cannulated and rinsed out via a hypotonic saline-heparin solution (5000 IE) until the perfusate was clear of body fluid. The lobular bronchus was connected to an airtight ventilation tube (Fa. VYGON 520 3.5 oral tube) and ventilated pressure-controlled (PEEP + 5 cm H2O, P1 = 20 cm H2O, frequency = 10/min) via a respirator. All lobes were perfused with Ringer solution at 42°C at normothermia and normotonia. In group 1 (n = 8), an atypical peripheral parenchymal resection (average resected surface: 2 × 2 cm(2)) and in group 2 (n = 8), a deep atypical parenchymal resection (average resected surface: 4 × 4 cm(2)) were performed with the Nd:YAG Laser LIMAX 120 (output power at 100 watts). After post-resection ventilation of 15 min, the resection surface was tested for airtightness and burst pressure. RESULTS: All group 1 lobes tested airtight under pressure-controlled ventilation. The mean burst pressure was 34.4 mbar (SD ± 3.2 mbar). Six lobes of group 2 were also completely airtight. The remaining two lobes, however, revealed a serious parenchymal leak (score 3). This was caused by the cross-opening of a segmental bronchus, although the surrounding lung parenchyma was also airtight. The mean burst pressure of these lobes was 31.7 mbar (SD ± 4.08 mbar). There was no significant difference between the two groups (P = 0.12). CONCLUSIONS: Peripheral lung defects after Nd:YAG Laser resection might not be sutured, since the laser-induced vaporization of the lung parenchyma seems to be initially airtight. These experimental data warrant confirmation in a controlled clinical study.

Stereotactic body radiotherapy for pulmonary metastases. Prognostic factors and adverse respiratory events.

PURPOSE: The aim of this retrospective study was to evaluate the feasibility, safety, and effectiveness of stereotactic body radiotherapy (SBRT) for pulmonary metastases. PATIENTS AND METHODS: Between April 2007 and March 2011, 87 patients underwent SBRT for pulmonary metastases using the in-house Air-Bag System(TM) to obtain the four-dimensional image for treatment planning and to reduce intrafractional intrathoracic organ motion with abdominal compression to reduce the risk of radiation pneumonitis. Survival and respiratory adverse events were analyzed. RESULTS: The 2- and 3-year overall survival (OS) rates were 47 and 32 %, and the corresponding cause-specific survivals were 52 and 36 %. The 2- and 3-year OS rates were 57 and 49 % for patients in group 1, respectively, while the corresponding OS rates were 48 and 21 %, and 40 and 32 % for patients in groups 2 and 3, respectively. The 2- and 3-year local control (LC) rates were 80 and 80 %, respectively. The corresponding intrathoracic progression-free survival rates were 40 and 32 %, respectively. Concerning adverse respiratory events after SBRT for pulmonary metastases, 14 % were grade 0 (G0), 66 % G1, 13 % G2, 6 % G3, and 1 % G4. Concerning the adverse respiratory events (NCI-CTC) by grade scale, 1- and 2-year cumulative probabilities of radiation pneumonitis were 12 and 20 % for G2 and 4 and 10 % for G3/4, respectively. The mean values for cumulative V20 were 11.6 ± 8.5 %, 29.8 ± 18.6 %, and 25.7 ± 12.8 % in G0/1, G2, and G3/4, respectively. The number of pulmonary metastases that could be safely treated with SBRT was 6 PTVs (or seven gross tumor volumes) within a cumulative V20 of 30 % under the restricted intrafractional respiratory tumor motion using the Air-Bag System(TM). CONCLUSION: We propose that the number of pulmonary metastases that can be safely treated with SBRT is 6 PTVs with a cumulative V20 of 30 % under the restricted respiratory tumor motion using the Air-Bag System(TM). SBRT for pulmonary metastases offers locally effective treatment for recurrent or residual lesions after first line chemotherapy.

Image-guided liver surgery: intraoperative projection of computed tomography images utilizing tracked ultrasound.

BACKGROUND: Ultrasound (US) is the most commonly used form of image guidance during liver surgery. However, the use of navigation systems that incorporate instrument tracking and three-dimensional visualization of preoperative tomography is increasing. This report describes an initial experience using an image-guidance system with navigated US. METHODS: An image-guidance system was used in a total of 50 open liver procedures to aid in localization and targeting of liver lesions. An optical tracking system was employed to localize surgical instruments. Customized hardware and calibration of the US transducer were required. The results of three procedures are highlighted in order to illustrate specific navigation techniques that proved useful in the broader patient cohort. RESULTS: Over a 7-month span, the navigation system assisted in completing 21 (42%) of the procedures, and tracked US alone provided additional information required to perform resection or ablation in six procedures (12%). Average registration time during the three illustrative procedures was <1 min. Average set-up time was approximately 5 min per procedure. CONCLUSIONS: The Explorer™ Liver guidance system represents novel technology that continues to evolve. This initial experience indicates that image guidance is valuable in certain procedures, specifically in cases in which difficult anatomy or tumour location or echogenicity limit the usefulness of traditional guidance methods.