What is the treatment planning volume that includes suspected positive lymph node chains called?

The treatment planning volume that includes suspected positive lymph node chains is referred to as the Clinical Target Volume (CTV). CTV encompasses not only the gross tumor that can be seen or palpated (known as the Gross Tumor Volume, GTV) but also any surrounding tissues and lymphatic regions that may harbor microscopic disease. It is crucial in treatment planning for radiation therapy as the CTV ensures that not only the known cancerous areas but also potential areas of spread are adequately treated to maximize treatment efficacy while minimizing damage to surrounding healthy tissues.

In the context of radiation therapy, incorporating suspected positive lymph nodes into the CTV is imperative when there is concern for nodal involvement based on clinical assessments or imaging findings. This comprehensive approach reduces the risk of cancer recurrence in those areas, illustrating why defining this volume accurately is vital for patient outcomes.