Correlation between parameters describing tumour motion and its location in the lungs

Area of Science:

• Medical Physics
• Radiotherapy
• Oncology

Background:

• Image-guided radiation therapy (IGRT) requires accurate characterization of tumour motion.
• Respiratory motion significantly impacts the precision of treating thoracic and abdominal tumours.

Purpose of the Study:

• To characterize respiratory-induced tumour motion.
• To establish correlations between tumour motion patterns and their anatomical locations within the lungs.

Main Methods:

• A piecewise linear model was used to represent tumour motion across breathing phases.
• Lung tumour locations were classified using broncho-pulmonary segments.
• Statistical analysis identified association rules between motion characteristics and location.

Main Results:

• A significant correlation was found between tumour motion amplitude and lung location.
• Tumours with small motion (<10 mm) were frequently located in the lung apex or attached to structures like the chest wall.
• Tumours with large motion (>20 mm) were typically found near the diaphragm or the lung periphery.

Conclusions:

• Tumour location is a predictive factor for respiratory motion characteristics in lung tumours.
• Understanding these correlations can improve the accuracy of image-guided radiation treatments.