Making sense of complex cancer cures

HYDERABAD: Radiation oncology or Radiation Therapy uses carefully targeted and regulated doses of high-energy radiation to shrink or eliminate cancer cells or tumors. It is one of the three main cancer treatment modalities along with surgery and chemotherapy. Radiation therapy is found to be most effective in treating cancers related to brain and spinal cord, head and neck, cervix, breast, lungs, bones and prostrate.

Most notable of machines used for radiation therapy are below:

TrueBeam STx: Uses a patented High-Intensity Mode that delivers dose rates which are two times faster and at a speed that is 60% faster than that of other accelerators. TrueBeam STx also reduces the collateral damage to healthy tissues that surrounds the tumor through better precision.
Tomotherapy or helical tomotherapy (HT): Radiation is delivered slice-by-slice and treats tumors one layer at a time. It combines an advanced form of intensity modulated radiation therapy (IMRT), with the accuracy of computed tomography (CT) scanning technology in one machine.

MRI-Linear Accelerator: Linear accelerator (linac) combined with a magnetic resonance imaging (MRI) scanner and improves survival, local, and regional tumor control. Benefits of the MR-linac compared with existing technologies is hypo-fractionated dose escalation to the tumor, which increases local control rates while having equal or decreased toxicity rates.RapidPlan & ARIA: RapidPlan is a knowledge-based treatment planning software to create consistent, efficient, higher quality plans for individualized radiation treatment planning. ARIA allows to develop disease-specific clinical protocols to facilitate a standard, consistent quality of care.

Most notable of technologies used for radiation therapy are discussed below:

Intensity Modulated Radiation Therapy (IMRT): Delivers radiation through the use of hundreds of tiny radiation beam-shaping devices which allow to target and deliver varying doses of radiation to different areas of tumor in a precise way causing fewer side effects.Image Guided Radiation Therapy (IGRT): Used for tumors located in areas that may change position between treatments due to bodily movements such as breathing and digestion. In order to account for these changes, IGRT uses repeated imaging scans conducted every day just before the patient receives radiation.

Rapid Arc: A rotational form of IMRT which is 4 times faster in delivering radiation. Reduced daily treatment time translates into better patient comfort due to less exposure to radiation.
The doctor is a consultant radiation oncologist, American Oncology Institute, Hyderabad.

Original Date: Sept 13 2017
Original Author: Dr Mirza Athar Ali