Introduction



Radiotherapy, also called radiation therapy, is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. It works by damaging the genetic material of cancer cells, making it difficult for them to grow and divide. Different types of radiation therapy are used for different purposes, including reducing tumor size before surgery, destroying cancer cells remaining after surgery and relieving symptoms like pain from advanced cancer.



Types of Radiotherapy



External Beam Radiation Therapy

External beam radiation therapy involves directing high-energy radiation from a machine outside the body towards the tumor site. This is the most common type used for treating various cancers. The radiation is carefully shaped to only affect the tumor cells while minimizing damage to healthy tissues. Multiple treatments are usually given over several weeks.



Brachytherapy

Brachytherapy, also called internal radiation therapy, involves placing radioactive sources inside or next to the tumor. This allows delivery of a very high dose of radiation directly to the cancer. It is used to treat cancers of the breast, prostate, head and neck, skin and some gynecological cancers. Brachytherapy can be temporary or permanent, depending on the placement of radioactive sources.



Systemic Radiotherapy

Systemic radiation therapy, also called unsealed or molecular radiation therapy, involves injecting radioactive material into the bloodstream. This allows the radiation to travel through the body and reach any tumors. Common examples include use of radioactive iodine to treat thyroid cancer and radiolabeled antibodies or peptides targeting certain tumor types. It treats cancers that have metastasized or spread to other organs.



Workings

At the microscopic level, radiation therapy works by damaging the DNA (genetic material) of cancer cells through direct ionization or production of free radicals. When the DNA is damaged beyond repair, the cells cannot continue to grow and divide leading to cell death. Since cancer cells divide faster than normal cells, they are more susceptible to the effects of radiation therapy.



The radiation is planned precisely using imaging scans of the patient to focus the beam accurately to the tumor area alone. Nearby healthy tissues also receive some radiation which can cause short term side effects. But most side effects are minimized by shaping and directing the radiation beam carefully and giving treatment in small daily fractions over several weeks. This allows neighboring healthy cells time to repair in between fractions.



Effects and Side Effects of Radiotherapy



Radiation therapy can cause both short term and long term side effects depending on the part of the body being treated. Common short term effects during or soon after treatment include fatigue, skin irritation where beam enters the body and low blood counts. Other effects are specific to the treatment site like mouth sores/dryness for head and neck radiation therapy.



Long term effects are relatively rare but can occur months or years after treatment depending on radiation dose and patient factors. These include permanent damage to certain organs, increased risk of select second cancers and cardiovascular conditions years later in some patients. Careful treatment planning and precision delivery techniques aim to minimize all potential side effects.



Radiation therapy provides long lasting control of the treated cancer in 60-80% of cases when combined with surgery and/or chemotherapy depending on the cancer type and stage. With advanced techniques utilizing imaging, computers and specialized equipment, radiation therapy remains a fundamental modality for curing or controlling many localized cancers. Ongoing research also enhances its effectiveness against metastatic and hard to treat cancers.



Conclusion



In summary, radiation therapy is a vital cancer treatment that leverages radiation's ability to kill tumor cells selectively. Standard options include external beam, internal radiation therapy and molecular targeted techniques. Careful planning ensures maximal dose to the tumor with minimal exposure to surrounding normal tissues. Short term side effects are usually tolerable, while long term effects are reducing with improving technology. Overall, radiation therapy provides either a curative or palliative intent for many cancer patients at various stages when used alone or combined with other treatments.

About Author:

Ravina Pandya, Content Writer, has a strong foothold in the market research industry. She specializes in writing well-researched articles from different industries, including food and beverages, information and technology, healthcare, chemical and materials, etc. (https://www.linkedin.com/in/ravina-pandya-1a3984191