Ex-Vivo Human Lung Tumor Model: Use for Temperature Measurements during Thermal Ablation of NSCLC

Zusammenfassung

Ziel: In dieser Studie wurde ein menschliches Ex-vivo-Lungenkrebsmodell verwendet, um die Temperaturentwicklung bei der Ablation mit 1 Laserfaser mit der Entwicklung beim Gebrauch von 2 Laserfasern zu vergleichen. Zudem wurde untersucht, ob die Temperaturdiffusion in normalem Lungengewebe von dem in Tumorgewebe abweicht. Material und Methoden: 48 Lungenpräparate, die nichtkleinzellige Bronchialkarzinome enthielten, wurden mit dem Ventilations- und Perfusionsmodell verbunden und mit 1 (22 Präparate, Gruppe 1) oder, in einer zweiten Phase, mit 1 (13 Präparate, Gruppe 2) oder 2 Laserfasern (13 Präparate, Gruppe 3) behandelt. Während der Ablation des Tumors wurde die Temperatur alle 5 s interstitiell gemessen. Ergebnisse: Eine Laserbehandlung und die Temperaturkontrolle war in allen Fällen technisch durchführbar. 30 min nach dem Beginn der Laserung mit 1 Faser wurde in 10 mm Entfernung von dieser eine Temperatur von 61 ± 17 °C in Gruppe 1 und von 74 ± 11 °C in Gruppe 2 erreicht (p = 0,1). In der Mitte zwischen 2 Laserfasern, die 20 mm voneinander entfernt waren, wurde eine Temperatur von 93 ± 7 °C erreicht. Nach 20-minütiger Ablation wurde in normalem Lungengewebe eine Temperatur von 77 ± 15 °C in 10 mm Entfernung erreicht. Schlussfolgerung: Das Ex-vivo-Modell ermöglicht die Durchführung der laserinduzierten Thermotherapie an einer perfundierten und ventilierten Lunge. Der Einsatz einer zweiten Laserfaser erhöht die Temperatur signifikant (p < 0,05). Die Temperaturentwicklung in normaler Lunge unterscheidet sich nicht signifikant von der in Tumorgewebe (p = 0,24).

Abstract

Purpose: In the present study we used an ex-vivo human lung cancer model to compare temperature diffusion during thermal ablation using one laser fiber to that of a two-fiber approach. Furthermore, we examined whether there was a difference between temperature diffusion in normal lung tissue and tumor tissue during laser ablation. Materials and Methods: 48 resected lung specimens containing non-small cell lung cancer were connected to a perfusion/ventilation apparatus and treated with 1 (22 specimens, group 1) or, in a second experiment, with 1 (13 specimens, group 2) or 2 (13 specimens, group 3) laser fibers. During tumor ablation, temperatures were measured interstitially every 5 sec. Laser ablation was followed by the taking of samples of 13 specimens for histological examination. For comparison we performed laser ablation in 7 specimens with normal lung tissue. Results: Laser treatment and temperature control were technically feasible in all samples. Thirty min after starting laser ablation with 1 fiber, a temperature of 61 ± 17 °C was achieved in group 1 at a distance of 10 mm from the laser fiber and a temperature of 74 ± 11 °C was achieved in group 2 (p = 0.1). In the middle between two active laser fibers placed 20 mm apart, a temperature of 93 ± 7 °C was achieved. The temperature reached in normal lung tissue after 20 min of laser ablation was 77 ± 15 °C at a distance of 10 mm from the laser fiber. Conclusion: The ex-vivo model allowed performance of laser-induced thermal ablation in the perfused and ventilated lung. The use of two laser fibers increases the achieved temperatures significantly (p < 0.05). Temperatures reached in normal lung tissue were as high as in tumor tissue (p = 0.24).

Key words

thorax - ablation procedures - interventional procedures

References

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