Table 1.
Cardiac-Sparing Modalities and Techniques in Radiation Therapy
| Cardiac-Sparing Technique | Description | Type of Cancer |
|---|---|---|
| Cardiac Displacement | ||
| Respiratory Gating | Tracking patient’s natural respiratory motion and delivering radiation precisely when the tumor is in the treatment field and farthest from the heart | Breast, Lymphoma, Lung, Esophagus |
| Deep Inspiration Breath Hold (DIBH) | Radiation is administered during maximal inspiration and breath hold, when the heart is pulled away from the chest wall due to flattening of the diaphragm and expansion of the lungs | Breast, Lymphoma |
| Prone Positioning/ Lateral Decubitus Positioning | Radiation is delivered to the tumor with patient lying prone or lateral decubitus on a specially designed table to maximally displace the heart from the treatment field | Breast |
| Radiation Treatment Modality/Technique | ||
| Involved Site Radiation Therapy (ISRT) and Involved Node Radiation Therapy (INRT) | Reduction in radiotherapy field size to involved-nodal tissue detected using modern imaging techniques (PET-CT/MRI), thus sparing surrounding uninvolved nodal and non-nodal anatomic structures | Lymphoma |
| Three-Dimensional Conformal Radiation Therapy (3D-CRT) | 3D reconstruction of the tumor and surrounding structures using CT and/or MRI imaging data to guide radiation planning by beam placement. Radiation can be delivered from any angle; multiple radiation beams from different angles can be combined to deliver maximal dose to the tumor while relatively sparing normal tissue | Breast, Lymphoma, Lung, Esophagus |
| Intensity-Modulated Radiation Therapy (IMRT) | An advanced form of 3D-CRT that utilizes varying intensity of smaller radiation beams (beamlets) using computerized inverse planning, enabling precise delivery of radiation dose to the tumor and improving normal tissue sparing | Breast, Lymphoma, Lung, Esophagus |
| Volumetric-Modulated Arc Therapy (VMAT) | An extended form of IMRT, in which the radiation source is continuously rotated around the patient, allowing delivery of therapy from a full 360° beam angle, with added advantage of improved delivery of radiation dose to the target in lesser time | Breast, Lymphoma, Lung, Esophagus |
| Image-Guided Radiation Therapy (IGRT) | Integration of imaging prior to and during each radiation treatment, typically CT-guided and recently MRI-guided, allowing more precise localization of the tumor bed. IGRT permits significantly better sparing of normal tissue while promoting dose-escalation to the tumor when incorporated with IMRT | Breast, Lymphoma, Lung, Esophagus |
| Accelerated Partial Breast Irradiation | An approach that treats only the lumpectomy bed plus a 1–2 cm margin, rather than the whole breast, therefore sparing normal tissue by decreasing the target volume of radiation | Breast |
| Proton Beam Therapy | Proton beams have a distinct property compared to photon beams: they quickly lose energy toward the end of their range (Bragg peak), thus limiting radiation dose beyond the target | Breast, Lymphoma, Lung, Esophagus |