MR Linac - New Era Of Cancer Care , 1st Of Its Kind In Northern India

MR Linac - New Era of cancerTechnological advancements in medicine

The field of medicine is undergoing rapid technological advances with the intent to improve the outcomes of treatment and provide a better quality of life to patients. 

Treatment of cancer is also witnessing huge advancement with the aim of providing personalised cancer care. It has not only improved the survival of patients but has also led to reduced treatment-related side effects which remains a concern for both patients and healthcare providers. Advances in cancer surgery like minimally invasive procedures and robotic surgeries and the introduction of targeted drugs and immunotherapy in medical oncology are some of the steps in that direction which have transformed current cancer care. 

Radiation therapy is an integral part of the treatment of cancer patients. The precision of treatment is of utmost importance to deliver a curative dose of radiation while minimising the side effects attributed to the dose to surrounding normal organs. 

Quantum jump in Cancer Care: 

Fortis Memorial Research Institute (FMRI), Gurugram has recently launched MR Linac - a major technological advancement in the field of Radiation Oncology (fig 1). It has paved the way for delivering highly accurate treatment for many types of cancers. MR Linac is a hybrid machine with MRI and Linear Accelerator in one and offers several advantages over currently available CT scan based Linear Accelerators. 

MR Linac integrates high-resolution 1.5 T MRI with 7 MV linear accelerator capabilities (fig 2), which provides real-time visualisation of tumors and surrounding tissues during radiation therapy. It provides higher soft tissue contrast to visualize the tumor precisely and deliver highly targeted radiation dose. Improvement in tumor control and reduction in side effects by MR guided radiation therapy (MRgRT) have been reported from many cancer centres across the globe. 

The current radiation technologies of IGRT (image guided radiation therapy) utilize CT scan-based images for tumor visualization and surrounding normal organs which has limitations in many tumor sites. With MR Linac we are able to visualize the tumor much better. Therefore, we can target the tumour more precisely with radiation. 

Online adaptation of radiation therapy: 

With MR Linac it is possible to see the progress of the tumor during the course of radiation therapy and adjust the radiation dose accordingly.  MR-guided radiation therapy (MRgRT) provides a quantum jump in the treatment of various cancers. It provides on line adaptation of treatment, which makes saving of surrounding normal tissues more reliable.

MR Linac is equipped with ‘CINE-MRI’ which provides real-time imaging of the tumour and surrounding critical organs which is crucial to detect any change in tumour position so that the treatment can be modified accordingly. It can lead to higher local control of cancer with a substantial reduction of radiation-related side effects. 

Which tumours can benefit from MR-Lina?

1. MR Linac has shown improvement in outcomes of many tumors like prostate cancer, pancreatic cancer, rectal cancer, liver cancers, head and neck cancers and brain tumors (fig 3).
2. Another critical advantage of the Elekta Unity MR Linac is the ability to provide ‘real time’ tracking of moving tumors. This feature is particularly beneficial for tumors in areas prone to movement like lung cancer, bladder cancer and prostate cancer. The MR guided adaptive radiation therapy ensures that the radiation dose conforms to the current geometry of the tumor which significantly enhances treatment accuracy and efficacy. 
3. Furthermore, MR Linac extends the boundaries of difficult to treat cancers. Its precision and adaptability makes it feasible to treat inoperable tumors, offering new hope for patients with challenging oncologic cases.It is also possible to assess the response to treatment with the help of functional imaging like DWI ( diffusion weighted imaging) and modify the treatment as necessary. 

The introduction of the Elekta Unity MR Linac at Fortis Memorial Research Institute underscores the institute’s dedication to advancing cancer care through cutting-edge technology. MR Linac became operational in August’2024 and this machine is 2^nd such equipment across India and 1^st in north India. It not only enhances the precision and effectiveness of radiation therapy but also aligns with the broader trend towards personalized cancer treatment. As we move forward, the MR Linac is set to play a pivotal role in the evolution of radiation oncology, offering a promising future for more effective, tailored, and less invasive cancer treatments. 

Dr Anil Kumar Anand

Guest Author MBBS,MD (PGI) Senior Director and Head, Department of Radiation Oncology Fortis Memorial Research institute, Gurugram