Chemotherapy: Open Access
Open Access

The Role of Radiation Therapy in Combination Cancer Treatment Plans

J E Meyer^* and Hiroshi Tada ^*Correspondence: J E Meyer, Department of Radiation Oncology, University of Della Svizzera Italiana, Lugano, Switzerland, Email:

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Description

Radiation therapy is a fundamental in the treatment of cancer, employed for its ability to destroy cancer cells and shrink tumors. The mechanisms by which radiation therapy works, its various types, the advancements that have enhanced its efficacy and safety. Radiation therapy or radiotherapy, uses high-energy radiation to damage the DNA of cancer cells, which impairs their ability to replicate and eventually leads to cell death. This treatment can be used alone or in combination with other modalities such as surgery, chemotherapy and immunotherapy. Radiation therapy works primarily by causing direct damage to the DNA within cancer cells. The ionizing radiation induces breaks in the Deoxyribonucleic Acid (DNA) strands, which can be single-strand breaks or more lethal double-strand breaks [1]. If the damage is extensive and irreparable, the cell undergoes apoptosis (programmed cell death).

Types of radiation therapy

Radiation therapy can be broadly categorized into External Beam Radiation Therapy (EBRT) and internal radiation therapy (brachytherapy). Each type has its specific applications, advantages, and limitations.

External Beam Radiation Therapy (EBRT): EBRT is the most common form of radiation therapy, where radiation is delivered from outside the body, targeting the tumor [2]. Advances in imaging and computing have led to several sophisticated EBRT techniques.

Intensity-Modulated Radiation Therapy (IMRT): IMRT allows the radiation dose to conform more precisely to the shape of the tumor by modulating the intensity of the radiation beams [3]. This technique minimizes the dose to surrounding normal tissues, reducing side effects.

Image-Guided Radiation Therapy (IGRT): IGRT uses imaging techniques such as Computed Tomography (CT) scans, Magnetic Resonance Imaging (MRI) or X-rays taken before and during radiation therapy to improve the precision and accuracy of treatment delivery.

Stereotactic Body Radiation Therapy (SBRT): SBRT delivers very high doses of radiation to a small, well-defined tumor area, often in fewer treatment sessions. It is particularly useful for treating small, localized tumors in organs such as the lungs, liver and spine.

Internal radiation therapy (Brachytherapy): Brachytherapy involves placing a radiation source directly inside or next to the tumor. This approach allows for a high radiation dose to the tumor while reducing exposure to surrounding healthy tissues [4].

High-Dose-Rate (HDR) brachytherapy: HDR brachytherapy delivers a high dose of radiation in a short amount of time, typically in minutes. It is often used for gynecological cancers, prostate cancer and certain head and neck cancers.

Low-Dose-Rate (LDR) brachytherapy: LDR brachytherapy involves placing radioactive seeds in or near the tumor, which release radiation over an extended period, such as days or weeks. This method is commonly used for prostate cancer.

Innovations in radiation therapy

Radiation therapy has seen significant advancements that have improved its precision, efficacy and safety [5]. These innovations have expanded the therapeutic window, allowing for higher radiation doses to tumors while minimizing harm to normal tissues.

Advanced imaging techniques: The integration of advanced imaging techniques, such as functional MRI, Positron Emission Tomography (PET) scans and cone-beam CT, has enhanced tumor visualization and treatment planning [6]. These imaging modalities provide detailed information about tumor size, shape and position, enabling more accurate targeting.

Radio genomics: Radio genomics studies the relationship between a patient’s genetic sequence and their response to radiation therapy. Understanding these genetic factors can help personalize radiation therapy, optimizing dose and minimizing toxicity for individual patients.

Combining radiation with other treatments: Combining radiation therapy with other treatment modalities, such as chemotherapy, immunotherapy and targeted therapies, can enhance the overall effectiveness of cancer treatment [7]. These combination approaches can synergistically kill cancer cells and reduce the likelihood of resistance.

Managing side effects: Despite its effectiveness, radiation therapy can cause side effects due to damage to healthy tissues. The type and severity of side effects depend on the treatment site, dose and individual patient factors.

Skin reactions: Redness, dryness and irritation at the treatment site.

Fatigue: A common side effect due to the body's effort to repair the damage caused by radiation.

Hair loss: In the treatment area, especially with head and neck radiation.

Oral complications: Dry mouth, difficulty swallowing and mouth sores with head and neck radiation.

Conclusion

The future of radiation therapy shows potential for further innovations and improved outcomes for cancer patients. Developing technologies that enable real-time adaptation of radiation therapy based on immediate changes in tumor position or patient anatomy will improve precision and outcomes. Radiopharmaceuticals, which deliver radiation directly to cancer cells through targeted molecules, are being explored for their potential to treat metastatic and difficult-to-reach tumors. Radiation can enhance the immune system's ability to recognize and attack cancer cells, potentially leading to more durable responses. Radiation therapy remains a critical component of cancer treatment, offering effective tumor control and, in many cases, cure. The field has seen remarkable advancements, from sophisticated imaging and delivery techniques to personalized treatment approaches. The integration of multidisciplinary approaches and personalized medicine will be key in realizing the full potential of radiation therapy in the fight against cancer.

References

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