Radiotherapy plays a crucial role in the care of cancer with approximately 50% of all patients benefiting from RT in the management of their disease.
In the last two decades technology has transformed the face of Radiation oncology. With the availability of better functional imaging modalities like PET CT scan and DW MRI, the tumours are better defined, leading to a more precise stage designation. This is of utmost importance as the treatment protocols are driven by the stage of the disease.RT techniques have changed significantly thanks to improvements in engineering and computing leading to state-of-the-art treatment techniques such as intensity-modulated RT (IMRT), volumetric-modulated arc therapy (VMAT), stereotactic body RT (SBRT) and adaptive RT (ART), which make possible a highly tailored dose distribution with maximum normal tissue sparing.
The current day cancer centres are equipped with the new generation Linear accelerates which are even capable of performing on-board imaging. Tumour localisation immediately before and during treatment delivery by means of image-guided techniques (IGRT) is becoming a part of clinical practice and is a fundamental prerequisite for high-precision RT.
In a nutshell, technological advances have mainly been the result of the integration of imaging information in every phase of the treatment, from simulation to planning to delivery.
As part of a comprehensive RT treatment process, adaptive RT (ART) techniques make it possible to modify the treatment plan during the course of RT in order to account for anatomical and biological changes.
Has technology improved cure rates?
Evolving from conventional irradiation using simple treatment fields towards highly conformal RT techniques, such as IMRT, VMAT and SRT improve the outcome by escalating the dose to the tumour and minimizing the toxicity to critical organs. Indeed, high-precision high dose RT has been called virtual surgery, since in many situations it can have a curative effect locally that is similar to surgery. From the biological point of view, such high doses induce different radiobiological mechanisms of cell killing and improve cure rates.
Has technology improved the quality of life of cancer patients?
Yes by saving the normal innocent organs from the harmful effects of radiation the quality of life has certainly improved. The current technology offers the ability of organ preservation approaches that are less morbid.
How do linear accelerators like Halcyon improve treatment delivery?
Most advanced treatment techniques like IMRT/SBRT are time-consuming especially when combined with image guidance (IGRT). Many patients find these long treatment intervals uncomfortable. The newer linear accelerators like HALCYON have faster treatment delivery which makes the treatment experience to the patient more comfortable.
There is a great advantage for patients who require radiation to a large area of the body (Magna field) like patients who are receiving Craniospinal irradiation or total body irradiation.
Craniospinal irradiation is a type of radiation that is done for certain brain tumours especially in children and Total Body Irradiation is the radiation to the whole body which is often required for patients undergoing bone marrow transplant. These techniques take 45-60 minutes of treatment time. But with machines like HALCYON, the treatment time is reduced to one third make it comfortable for the patient. HALCYON has 100% image guidance technology so it also makes the treatment very precise.
So this newer technology is a hope rather than a hype for cancer patients.
Dr. Kanika Sharma, Clinical Lead & Senior Consultant – Oncology, Radiation Oncology, Dharamshila Narayana Superspeciality Hospital, Delhi