What is Radiation Therapy?

Radiation treatment delivers targeted intervention designed to eradicate cancer cells while sparing surrounding healthy tissues. Its main ideal is that it operates on the principle of precision, directly administering high-energy radiation beams with pinpoint accuracy to target cancerous tumors.

By harnessing the power of radiation, radiation oncologists can achieve a range of therapeutic goals, from curative intent to palliation, ultimately improving outcomes and quality of life for cancer patients.

The mechanism of action behind radiation therapy is rooted in the ability of ionizing radiation to damage the DNA within cancer cells, leading to cell death or impaired proliferation.

This targeted approach allows radiation therapy to selectively target and destroy cancer cells while minimizing damage to adjacent normal tissues.

In what follows, we’ll discuss the different treatment modalities, the varying types of cancer treated, and the strategies employed to optimize outcomes for individuals with cancer.

Types of Radiation Therapy

Radiation therapy stands as a critical component of cancer treatment modalities, utilizing targeted doses of high-energy radiation to destroy cancer cells or inhibit their growth.

In the field of radiation therapy, several distinct approaches exist, each matched to meet the specific needs of individual patients and their unique cancer diagnoses.

External Beam Radiation Therapy (EBRT)

External beam radiation therapy, usually identified as just “radiation therapy,” delivers high-energy radiation beams from an external source directed precisely at the tumor site.

This approach precisely targets cancer cells while minimizing exposure to surrounding healthy tissues. EBRT is commonly used to treat a wide range of cancers, including breast cancer, prostate cancer, lung cancer, and head and neck cancers.

Internal Radiation Therapy (Brachytherapy)

Internal radiation therapy, also known as brachytherapy, involves the placement of radioactive sources directly within or near the tumor site.

These radioactive sources emit radiation over a specified period, delivering high doses of radiation to the cancerous cells while sparing nearby healthy tissues. Brachytherapy is often used to treat cancers of the cervix, prostate, uterus, and other organs, offering precise and localized radiation delivery.

Systemic Radiation Therapy (Radioisotope Therapy)

Systemic radiation therapy, or radioisotope therapy, involves the administration of radioactive substances, known as radioisotopes or radiopharmaceuticals, via injection, oral ingestion, or intravenous infusion.

These radioactive substances travel through the bloodstream, selectively targeting cancer cells throughout the body.

Systemic radiation therapy is particularly effective in treating cancers that have spread (metastasized) to multiple sites or are difficult to access with other treatment modalities. It is commonly used to treat thyroid cancer, certain types of neuroendocrine tumors, and bone metastases.

Cancers Treated via Radiation

Radiation therapy exhibits versatility as a treatment modality for cancer, offering targeted and effective interventions for several types of malignancies.

In the field of oncology, many cancers are treated with radiation therapy, and each type often requires unique treatment approaches.

Breast Cancer

Radiation therapy is regularly involved in the comprehensive treatment of breast cancer, often acting as an adjuvant therapy alongside surgery and systemic therapies. Following breast-conserving surgery (lumpectomy), radiation therapy is often recommended to target any remaining cancer cells in the breast tissue.

Additionally, radiation therapy may be further utilized post-mastectomy to reduce the risk of cancer recurrence in the chest wall or lymph nodes. With advancements in radiation techniques such as accelerated partial breast irradiation (APBI) and intensity-modulated radiation therapy (IMRT), radiation oncologists can precisely target the tumor bed while sparing surrounding healthy tissues, minimizing side effects and optimizing outcomes for breast cancer patients.

Prostate Cancer

Radiation therapy is often standard in the treatment of localized prostate cancer, offering curative intent while preserving quality of life. External beam radiation therapy (EBRT), delivered using techniques such as intensity-modulated radiation therapy (IMRT) or stereotactic body radiation therapy (SBRT), is the usual method for prostate cancer.

Additionally, brachytherapy, or internal radiation therapy, involves the placement of radioactive seeds directly into the prostate gland, delivering targeted radiation while minimizing exposure to surrounding tissues. These approaches offer effective tumor control and excellent long-term outcomes for patients with localized prostate cancer, particularly those with low to intermediate-risk disease.

Lung Cancer

The management of both early-stage and advanced lung cancer often involves radiation therapy as a primary treatment modality or in combination with surgery, chemotherapy, or targeted therapies.

For patients with early-stage non-small cell lung cancer (NSCLC) who are not surgical candidates, stereotactic body radiation therapy (SBRT) offers a non-invasive alternative to achieve tumor control rates and minimal side effects.

In advanced or metastatic lung cancer, radiation therapy may be used to palliate symptoms such as pain, shortness of breath, or coughing, improving quality of life and extending survival.

Brain Cancer

Finally, radiation therapy is a therapy in the multidisciplinary management of primary and metastatic brain tumors, offering targeted treatment to control tumor growth and alleviate symptoms.

For patients with primary brain tumors such as gliomas or glioblastomas, radiation therapy is a part of treatment following surgical resection, or it may be used as a primary treatment modality in cases where surgery is not feasible.

In the setting of metastatic brain tumors, radiation therapy, often delivered using techniques such as stereotactic radiosurgery (SRS) or whole-brain radiation therapy (WBRT), can effectively target and control multiple lesions throughout the brain, improving neurological function and quality of life for patients with advanced disease.

Final Thoughts

Radiation therapy encompasses a spectrum of treatment modalities that are designed to target and eradicate cancer cells while preserving surrounding healthy tissues.

From the precision of external beam radiation therapy to the localized delivery of internal radiation therapy and the generalized approach of systemic radiation therapy, each type of radiation therapy offers unique advantages in treatment therapy for cancer.