Radiation Therapy for Head & Neck Cancers: History, Types, Advances & Outcomes

Radiation therapy is a cornerstone of treatment for head and neck cancers, a diverse group of malignancies arising in the oral cavity, pharynx, larynx, nasal cavity, paranasal sinuses, salivary glands, and oropharynx. These cancers require multidisciplinary care, and radiation therapy plays a crucial role either alone or in combination with surgery and chemotherapy. Millions of patients worldwide benefit from targeted radiation therapy designed to destroy cancer cells while minimizing damage to surrounding healthy tissues.

History of Radiation Therapy in Head & Neck Cancer

Radiation therapy traces its origins to the discovery of X-rays by Wilhelm Röntgen in 1895 and the identification of radium by Marie and Pierre Curie soon after. Early applications in the 20th century used superficial X-rays and radium applicators with limited dose control and significant side effects.

Technological advances led to the development of megavoltage linear accelerators, allowing deeper tumour penetration and improved targeting. Over recent decades, radiation therapy has evolved into highly precise, computer-guided techniques such as IMRT, IGRT, SBRT, and proton therapy, significantly improving tumour control while reducing toxicity.

Causes of Head & Neck Cancers (Including Indian Data)

Tobacco Use

Tobacco use in all forms — cigarettes, bidis, gutka, khaini, and paan with tobacco — is the leading cause of head and neck cancers in India. Smokeless tobacco is strongly associated with cancers of the oral cavity.

Alcohol Consumption

Alcohol acts synergistically with tobacco and significantly increases the risk of cancers of the oropharynx, hypopharynx, and larynx.

Human Papillomavirus (HPV)

HPV, particularly HPV-16, is an increasingly important cause of oropharyngeal cancers. Indian data show a rising incidence among younger patients.

Poor Oral Hygiene & Environmental Factors

Poor dental care, nutritional deficiencies, chronic irritation, and occupational exposure to chemicals contribute to disease risk.

Types of Radiation Therapy Used in Head & Neck Cancers

• IMRT (Intensity-Modulated Radiation Therapy): Precisely shapes radiation dose to the tumour while sparing normal tissues.
• IGRT (Image-Guided Radiation Therapy): Uses daily imaging for accurate tumour targeting.
• SBRT (Stereotactic Body Radiation Therapy): Delivers high-dose radiation in few sessions for selected cases.
• Proton Therapy: Minimizes radiation exposure to surrounding organs using particle beams.
• Brachytherapy: Places radioactive sources directly within or near the tumour.

Recent Advances in Radiation Therapy

Precision Targeting

Integration of MRI and PET-CT imaging allows superior tumour delineation and improved treatment accuracy.

Adaptive Radiation Therapy

Radiation plans are adjusted during treatment to account for anatomical and tumour changes.

Reduced Toxicity Protocols

De-intensification strategies in selected HPV-positive cancers aim to preserve excellent control with fewer long-term side effects.

Potential Side Effects of Radiation Therapy

• Oral mucositis
• Skin irritation
• Fatigue
• Difficulty swallowing
• Xerostomia (dry mouth)
• Dental and thyroid-related complications

Results & Outcomes After Radiation Therapy

• High Locoregional Control: Especially with IMRT and chemoradiation
• Improved Survival: Better outcomes in HPV-positive disease
• Organ Preservation: Maintains speech and swallowing
• Indian Clinical Evidence: Outcomes comparable to global standards with modern protocols

Conclusion

Radiation therapy remains a fundamental and highly effective treatment for head and neck cancers. From early X-ray treatments to advanced precision techniques, radiation oncology has transformed patient outcomes. With continued innovation and personalised treatment approaches, radiation therapy offers improved survival, reduced toxicity, and better quality of life for patients in India and worldwide.