External radiotherapy of thyroid cancer

Area of Science:

• Oncology
• Endocrinology
• Radiotherapy

Background:

• Thyroid cancer encompasses several subtypes, including differentiated (papillary, follicular), medullary, and anaplastic.
• Differentiated thyroid cancers are typically hormone-sensitive, responding to thyroid-stimulating hormone (TSH) suppression.
• Standard treatment for differentiated thyroid cancer involves surgery, radioactive iodine ((131)I) therapy, and hormone suppression.

Purpose of the Study:

• To review the role and indications of external radiotherapy in managing various types of thyroid cancer.
• To outline current treatment strategies for differentiated, medullary, and anaplastic thyroid cancers.

Main Methods:

• Review of existing literature and treatment guidelines for thyroid cancer management.
• Analysis of the efficacy of adjuvant external radiotherapy in specific clinical scenarios.
• Evaluation of combined treatment modalities for advanced thyroid cancer types.

Main Results:

• External radiotherapy is controversially discussed for differentiated thyroid cancer, but recommended for extra-capsular extension and potentially for lymph node involvement or incomplete resection.
• External beam radiotherapy shows benefit in medullary thyroid cancer for unresectable, residual, recurrent, or metastatic disease.
• Combined modality treatment (surgery, external irradiation up to 60 Gy, chemotherapy) improves local control and survival in anaplastic thyroid cancer.

Conclusions:

• Treatment decisions for thyroid cancer, particularly regarding external radiotherapy, require individualized assessment based on cancer type and stage.
• External radiotherapy plays a crucial role in specific settings for medullary and anaplastic thyroid cancers, improving patient outcomes.
• Combined treatment approaches are essential for achieving better local control and prolonged survival in aggressive thyroid cancer subtypes.