3. What is Radiotherapy? It is a high speed ionizing radiation. Works by damaging the DNA within cancer cells and destroying their ability to reproduce. When the damaged cancer cells are destroyed by radiation, the body naturally eliminates them.
4. What is Radiotherapy? Double-stranded breaks of nuclear DNA seems to be the most important cellular effect of radiation
5. What about Normal Cells? Normal cells can be affected by radiation, but they are able to repair themselves.
6. Radiotherapy: Sometimes radiation therapy is the only treatment a patient needs. Other times, it is combined with other treatments, like surgery and chemotherapy.
8. Different Uses of Radiotherapy: To cure cancer: Destroy tumors that have not spread to other body parts. Reduce the risk that cancer will return after surgery or chemotherapy. To reduce symptoms: Shrink tumors affecting quality of life, like a tumor that is causing shortness of breath. Alleviate pain by reducing the size of a tumor.
11. Types of Radiotherapy: External: Delivers radiation using a linear accelerator. To reduce symptoms: Also, is called brachytherapy or seed implants. involves placing radioactive sources inside the patient.
13. External Radiotherapy:Specialized Types: Three-Dimensional Conformal Radiation Therapy (3D-CRT) Uses CT or MRI scans to create a 3-D picture of the tumor. So, beams are precisely directed to avoid radiating normal tissue.
14. External Radiotherapy:Specialized Types: Intensity Modulated Radiation Therapy (IMRT) A specialized form of 3D-CRT. Involves the use of varying intensities of hundreds of small radiation beams “bamelets” to produce dosage distributions that are more precise than 3D-CRT.
32. Radioactive Isotopes: Involves injecting radioactive isotopes either into a vein or into an organ. E.g.,: Radioactive Iodine I131 : (thyroid Cancer). Hormone-bound lutetium-177: (Neurendocrine Tumor) Strontium-89 (Metastron),…etc.
35. Uses of Radiotherapy: Used in treatment of tumor either as: Curative: To resect the tumor. Adjuvant, After resection to prevent the recurrence. Neoadjuvant, or Before surgery to reduce the size of tumor. Palliative. To decrease the severity of tumor and to delay the progression.
36. Uses of Radiotherapy: The pattern of treatment depends on: Tumor type, Location, Stage, The general health of the patient
43. Acute Side Effects: Damage to the epithelium surfaces: Skin & Mucus Membrane. In head & neck: Temporary soreness and ulceration commonly occur in the mouth and throat. Unlike chemotherapy, radiation usually doesn’t cause hair loss or nausea.
44. Late Side Effects: occur months to years after treatment. E.g,: Fibrosis. Dryness: The salivary glands and tear glands have a radiation tolerance . The tolerance of salivary & tear glands is exceeded by most radical head and neck cancer treatments.
46. Is Radiation Therapy Safe? Many advances have been made in the field to ensure it remains safe and effective. Multiple healthcare professionals develop and review the treatment plan to ensure that the target area is receiving the dose of radiation needed.