Table 1.
Different Types of External Beam Radiation Therapy (EBRT) Techniques and Associated Advantages and Disadvantages
| S.No. | External Beam Radiation Therapy (EBRT) Technology | Types of Cancer Treated | Advantages | Disadvantages |
|---|---|---|---|---|
| 1. | 3 dimensional conformal radiotherapy (3DCRT) | Brain tumors, breast cancer, gastrointestinal (GI) cancer, lung cancer and gynecologic malignancies. | Improve short-term response rate, reduce mouth dryness and parotid gland injury, and promote the prognosis of patients with nasopharyngeal carcinoma. | Shows higher gastrointestinal toxicities in patients with endometrial cancers. Difficult to perform correct quality procedures, positioning, imaging, contouring, dosimetry, follow-up, and dose delivery |
| 2. | Intensity modulated radiotherapy (IMRT) | Head and neck, prostate, breast, lung, brain, gynecologic, and GI cancers. | Provides high conformity and high precision. | IMRT is prone to geometrical errors, due to higher dose conformity indices. |
| 3. | Volumetric modulated arc therapy (VMAT) | Head and neck, non-small cell lung cancer (NSCLC), prostate, gastrointestinal, gynecological, thoracic, central nervous system, and breast tumors | Provides a full 360° of beam directions with the entire dose volume delivered in a single rotation VMAT treatment shows a lower risk of OAR irradiation and has better homogeneity compared to IMRT. Significant role in uncomfortable immobilization. |
Increase in the low dose radiation to the surrounding tissues and organs, with a greater chance of having secondary malignancies. |
| 4. | Image guided radiotherapy (IGRT) | Prostate, lung and head and neck cancers | Significant reduction in set-up margins resulting in reduced toxicities in sites with demonstrable, quantifiable, and correctable inter- and/ or intra- fraction motion | Uncertainties in target volume delineation, image quality, longer acquisition times, high intra-fractional errors, and extra-dose delivery during daily imaging |
| 5. | Stereotactic body radiation therapy (SBRT) | Prostate, head and neck, spinal, renal, oligo metastases, and pancreatic | Provides high doses of radiation to the tumor and has low risk of postoperative risk and death. | Post treatment side-effects. |
| 6. | Particle therapy Proton Neutron Carbon |
Stage II–III NSCLC, prostate carcinoma, chordoma and hepatocellular carcinoma etc. | Particle radiation has a higher biological effectiveness and is very effective in radio-resistant cancers. | The production of particle radiation therapy is much more expensive than the production of photons, and has more logistical requirements |
| 7. | Photodynamic therapy (PDT) | Esophageal, non-small cell lung cancer and Barrett's esophagus patients | PDT specifically accumulates into tumors and uses intense non-thermal visible light source. | Success of PDT is limited by uptake and localization of the photosensitizer, the method of light delivery, spatio-temporal organization and location of tumors, singlet and triplet quantum yields, and associated side-effects |