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Purpose Perfusion-mediated tissue cooling has often been described in the literature for thermal ablation therapies of liver tumors. The objective of this study was to investigate the cooling effects of both perfusion and ventilation during laser ablation of lung malignancies. Materials and methods An ex vivo lung model was used to maintain near physiological conditions for the specimens. Fourteen human lung lobes containing only primary lung tumors (non-small cell lung cancer) were used. Laser ablation was carried out using a Nd:YAG laser with a wavelength of 1064 nm and laser fibers with 30 mm diffusing tips. Continuous invasive temperature measurement in 10 mm distance from the laser fiber was performed. Laser power was increased at 2 W increments starting at 10 W up to a maximum power of 12–20 W until a temperature plateau around 60 °C was reached at one sensor. Ventilation and perfusion were discontinued for 6 min each to assess their effects on temperature development. Results The experiments lead to 25 usable temperature profiles. A significant temperature increase was observed for both discontinued ventilation and perfusion. In 6 min without perfusion, the temperature rose about 5.5 °C (mean value, P Conclusion Ventilation- and perfusion-mediated tissue cooling are significant influencing factors on temperature development during thermal ablation. They should be taken into account during the planning and preparation of minimally invasive lung tumor treatment in order to achieve complete ablation.

Preoperative chemotherapy improves survival in patients with stage III non-small-cell lung cancer (NSCLC) amenable to resection. We aimed to assess the additional effect of preoperative chemoradiation on tumour resection, pathological response, and survival in these patients.Between Oct 1, 1995, and July 1, 2003, patients with stage IIIA-IIIB NSCLC and invasive mediastinal assessment from 26 participating institutions of the German Lung Cancer Cooperative Group (GLCCG) were randomly assigned to one of two treatment groups. The intervention group were scheduled to receive three cycles of cisplatin and etoposide, followed by twice-daily radiation with concurrent carboplatin and vindesine, and then surgical resection (those with positive resection margins or unresectable disease were offered further twice-daily radiotherapy). The control group were scheduled to receive three cycles of cisplatin and etoposide, followed by surgery, and then further radiotherapy. The primary endpoint was median progression-free survival (PFS) in patients eligible for treatment after randomisation. Secondary endpoints in patients eligible for treatment after randomisation were overall survival (OS) and the proportion of patients undergoing surgery. Secondary endpoints in patients with tumour resection were the proportion with negative resection margins, the proportion with complete resection, the proportion with histopathological response, and the proportion with mediastinal downstaging. Additionally, exploratory (not prespecified) post-hoc analyses in terms of PFS and OS were done on patients not amenable to resection and on further subgroups of patients undergoing resection. Analyses were by intention to treat. This trial is registered on the ClinicalTrials.gov website, number NCT 00176137.558 patients were randomly assigned. 34 patients did not meet inclusion criteria and were excluded. Of 524 eligible patients, 142 of 264 (54%) in the interventional group and 154 of 260 (59%) in the control group underwent surgery; 98 of 264 (37%) and 84 of 260 (32%) underwent complete resection. In patients with complete resection, the proportion of those with mediastinal downstaging (45 of 98 [46%] and 24 of 84 [29%], p=0.02) and pathological response (59 of 98 [60%] and 17 of 84 [20%], p0.0001) favoured the interventional group. However, there was no difference in PFS (primary endpoint) between treatment groups-either in eligible patients (median PFS 9.5 months, range 1.0-117.0 [95% CI 8.3-11.2] vs 10.0 months, range 1.0-111.0 [8.9-11.5], 5-year PFS 16% [11-21] vs 14% [10-19], hazard ratio (HR) 0.99 [0.81-1.19], p=0.87), in those undergoing tumour resection, or in patients with complete resection. In both groups, 35% of patients undergoing surgery received a pneumonectomy (50/142 vs 54/154). In patients receiving a pneumonectomy, treatment-related mortality increased in the interventional group compared with the control group (7/50 [14%] vs 3/54 [6%]).In patients with stage III NSCLC amenable to surgery, preoperative chemoradiation in addition to chemotherapy increases pathological response and mediastinal downstaging, but does not improve survival. After induction with chemoradiation, pneumonectomy should be avoided.German Cancer Aid (Bonn, Germany).

To detect bronchial carcinoma by autofluorescence, we measured the spectra of tumor and normal tissue in situ, in an in vivo model and in vitro by fiber optic spectrometer and two-dimensional resolved microspectroscopy. The in situ measurements were performed in bronchi of nine patients with squamous cell carcinoma during regular bronchoscopy with autofluorescence assistance. The fluorescence was monitored with a fiber optical spectrometer under blue light excitation (lambda=405nm). In an in vivo model, the resected lobe of a lung was perfused under physiological conditions. Tumorous and normal tissues were examined spectroscopically during perfusion and after blood removal and substitution with formol. In another setup the wavelength dependency of autofluorescence was examined on resected parts of physiological bronchi and central bronchial carcinomas. Under the variation of the excitation from 385 to 465nm the autofluorescence response was monitored with a fiber optic spectrometer. For investigation of the origin of autofluorescence, two-dimensional resolved spectroscopy was performed with the SpectraCube system on several sections of tumor and normal tissues All measurements, performed in vivo, in the in vivo model and in vitro agreed, that the main difference of the autofluorescence between tumor and normal bronchus tissue is the intensity of the fluorescences' main peak at 505nm. The signal on tumor tissue is in all cases significantly lower than that of normal tissue. The shape of the autofluorescence peaks is in healthy and carcinoma tissue approximately the same with two characteristic minima at 540 and 580nm. After the preparation with formaldehyde those minima disappeared from the spectra. A comparison with the absorption spectra of hemoglobin showed, that the variation of the spectra may be due to the blood content in the tissue. Two-dimensional spatially resolved spectroscopy showed, that the lower intensity of fluorescence in tumor tissue is due to the irregular and low-concentrated formation of fluorescent structures, which seen to be the elastic structures of bronchial tissue.