Standardisation of Target Volume Delineation for Carotid-sparing Intensity-modulated Radiotherapy in Early Glottis...

Area of Science:

• Radiation Oncology
• Head and Neck Cancer Research

Background:

• Carotid-sparing intensity-modulated radiotherapy (IMRT) is being explored for early laryngeal glottis cancer to mitigate long-term carotid toxicity.
• Concerns exist regarding potential geographical misses and other normal tissue toxicities associated with this technique.

Purpose of the Study:

• To systematically review the current literature on carotid-sparing IMRT for early glottis cancer.
• To focus on the definitions of target volumes and carotid arteries as organs at risk.
• To propose recommendations for standardizing structures, dose constraints, and dose reporting.

Main Methods:

• A systematic review of 16 articles, selected from 73 references.
• Included studies comprised two case reports, 11 planning studies, and three prospective studies.

Main Results:

• Significant variation and lack of consensus were found in target volume definitions, particularly for the clinical target volume.
• Carotid artery and spinal cord delineation were inconsistently defined, and most studies lacked specific carotid artery dose constraints.
• Delineation of carotid artery length varied across studies, despite most reporting mean doses.

Conclusions:

• A lack of consensus in target volume definitions for carotid-sparing IMRT is evident.
• Long-term prospective data are essential to confirm the benefits of carotid-sparing IMRT.
• Establishing consensus on target volume definition, dose constraints, and reporting is crucial for future standardization.