TITLE:
The Journey of SRS: An Initial Experience of Starting Sterotactic Radiosurgery Facility at Purbanchal Cancer Hospital—First in Nepal
AUTHORS:
Birendra Kumar Yadav, Karthik Nagamuthu, Alok Thakur, Kushal Rizal, Umesh Kumar Sharma, Ujwal Rai, Dinesh Thapa, Shishir Thapa, Kumar Chinnappan, Amit Kumar Dubey, Suraj Gurung, Aman Yadav, Utpalkant Kumar, Ranjay Kumar
KEYWORDS:
Conformity Index, Double Shell Positioning System, Electronic Portal Imaging Device, Linear Accelerator, Millennium MLC, Octavius Detector 1500, Setup Field
JOURNAL NAME:
International Journal of Medical Physics, Clinical Engineering and Radiation Oncology,
Vol.12 No.2,
April
19,
2023
ABSTRACT: Introduction: Radiotherapy (RT) is a vital cancer treatment modality for both
curative and palliative purposes. Nepal is a developing country with a
population of around 30 million people. Cancer affects 100 - 120 people out of
every 100,000, and the figure is increasing. The number of radiation facility
machines in the country is still countable in fingers. Purbanchal Cancer
Hospital, Nepal is the first comprehensive cancer facility capable of
performing stereotactic radiosurgery (SRS). Our facility has cutting-edge Varian
Truebeam Linear Accelerators with millennium MLC, which makes SRS and SRT’S for
intracranial lesions such as small benign and malignant tumors much easier. In
addition to SRS, we are the pioneers of SBRT for lung using 4DCT, interstitial
& intraluminal brachytherapy, RPM Gated & DIBH modalities in Nepal. Methods & Materials: The purpose of this study is to share our
experience in establishing an SRS facility in the country, which includes
training the RT team on the importance of process accuracy, patient selection,
patient assessment, mould preparation, and describing image data acquisition,
target, and organ at risk delineation on CT and MRI images, treatment planning
process, and quality assurance. Results & Discussion:
The plans for all SRS and SRT cases are based on target coverage, OAR sparing,
hotspot inside the target, conformity index, heterogeneity index, and dose fall
off. To select the final plan, we used strict passing criteria such as a
conformity index Paddick (CIPaddick) more than 0.85, a falloff between 100% and
50% of less than 5.5 mm (maximum 6 mm in irregular targets), and a hotspot inside
the target between 115 to 140 percent, as per clinical standards. In addition,
we determined the CILomax and CIRTOG for each case. Passing criteria for
verification plans are set as minimum of 95% for a 2% percentage dose
difference (% DD) and a 2-mm distance to an
agreement (DTA). We also gathered demographic data from patients treated
in the first year, such as diagnosis, lesion size, dose fraction, heterogeneity
index (HI), conformity index (CI) and gamma index. SRS/SRT treatment was
successfully implemented, and over 40 patients were treated with positive
clinical outcomes. Conclusion: SRS
now has a wider range of alternatives, thanks to technology advancements in
recent years. SRS’s dosimetric advantages have steadily been extended to
extracranial locations. Purbanchal Cancer Hospital, Birtamode, Nepal
established a comprehensive cancer facility with qualified workforce with the
goal of providing high-quality treatment to the people of Nepal.