Assessment of cisplatin concentration and depth of penetration in human lung tissue after hyperthermic exposure.

OBJECTIVES: The effects of cisplatin on the lung parenchyma during hyperthermic intrathoracic chemotherapy perfusion have not been analysed in detail. The objective of this study was to evaluate both the concentration and depth of the penetration of cisplatin in human lung tissue after hyperthermic exposure under ex vivo conditions.
METHODS: This experimental study was approved by the local ethics committee. Twelve patients underwent pulmonary wedge resections after elective thoracic lobectomies were performed (resected lobe), and the lung tissue (approximately 1-2 cm(3)) was incubated (in vitro) with cisplatin (0.05 mg/ml; 60 min, 42°C). Subsequent tissue beds (depth, 0.5 mm; median weight, 70-92 mg) were prepared from the outside to the middle, and the amount of cisplatin per tissue weight was analysed using atomic absorption spectrometry. Afterwards, the penetration of cisplatin depth was calculated and related to the different concentrations per tissue.
RESULTS: Cisplatin penetrated into the human lung tissue after ex vivo hyperthermic exposure. The median amount of platinum [nmol cisplatin/g lung tissue] decreased significantly (P ≤ 0.05) depending on the penetration depth: 32 nmol/g (1 mm), 20 nmol/g (2 mm) and 6.8 nmol/g (4 mm). The calculated median concentrations of cisplatin (µg/ml) were 2.4 µg/ml (1 mm), 1.4 µg/ml (2 mm) and 0.5 µg/ml (4 mm), respectively.
CONCLUSIONS: Under ex vivo hyperthermic conditions, cisplatin diffused into human lung tissue. The median penetration depth of the cisplatin was approximately 3-4 mm. The penetration of cisplatin into lung tissue may affect the local therapy of residual tumour cells on the lung surface using hyperthermic intrathoracic chemotherapy perfusion in patients with malignant pleural tumours.