Radiotherapy medical physics in the Philippines: A contemporary overview

Abstract

Purpose: With cancer ranking as the third leading cause of death in the Philippines and a disparity in healthcare resources across regions, this research aimed to assess the state of radiotherapy medical physics in the country.

Methodology: The study utilized a comprehensive online survey with 94 structured questions answered by 19 clinics.

Results: Most of the participants were within 1-3 years of training (41%), with a slight majority working in private hospitals (55%). linear accelerators (LINACs) were universally used with one Co-60 unit available, and High Dose Rate (HDR) brachytherapy was common. Intensity-Modulated Radiotherapy (IMRT) and 3D-Conformal Radiotherapy (3D-CRT) are practiced in all 19 clinics, with advanced techniques like Stereotactic Body Radiotherapy (SBRT), Stereotactic Radiosurgery (SRS), and Intraoperative Radiotherapy (IORT) limited to NCR, while modalities such as Volumetric Modulated Arc Therapy (VMAT) (21%) and 2D RT (68%) are more widely practiced. Imaging modalities included the wide adoption of Computed Tomography (CT), though only 64% of respondents had dedicated CT simulators in their clinics. Gynecologic and breast cancers were frequently treated, while bone marrow transplants (total body irradiation) were rare. For quality assurance (QA) devices, Solid Water Phantoms and Scanning Water Tanks (86%) were the most common devices for dosimetry and measurement. 82% reported performing patient-specific QA (PSQA), with EPID dosimetry being the most common (55%) PSQA device used. Quality management practices varied between Qualified Medical Physicists and Medical Physics Trainees, with most Qualified Medical Physicists performing routine checks. Treatment interruptions were mainly due to staffing and machine downtime, rather than power outages or natural disasters. Most clinics had their own systems (86%) to document safety incidents, but only a few reported incidents (32%) to the IAEA SAFRON program. Lastly, participants expressed a willingness to collaborate in research despite limited time.

Conclusion: This study provides an understanding of the current landscape of radiation therapy physics in the Philippines, highlighting the need to address workforce disparities, ensure equitable cancer treatment access, optimize dosimetric tools and QA devices, and prioritize resource allocation and research collaboration to advance radiation oncology practices.

Keywords: dosimetric tool availability; quality assurance; radiotherapy equipment; radiotherapy safety practices; treatment interruptions.

FIGURE 1

(a–d) Frequency distribution of the utilization of LINAC, Co‐60 teletherapy, and brachytherapy: HDR, LDR, and Permanent (a), TPS for radiotherapy (b), brachytherapy practices (c), and geographical distribution of radiotherapy practices (IMRT and 3D‐CRT) among 19 Clinics (d). 3D‐CRT, 3D‐Conformal Radiotherapy; HDR, high dose rate; IMRT, intensity‐modulated radiotherapy; LDR, low dose rate; LINAC, linear accelerators; TPS, treatment planning system.

FIGURE 2

(a,b) Frequency distribution of the utilization of imaging modalities (MRI, PET/CT, CT, SPECT) (a) and location of CT simulator in radiation oncology clinics (b). MRI, Magnetic Resonance Imaging; PET/CT, Positron Emission Tomography/Computed Tomography; SPECT, Single Photon Emission Computed Tomography.

FIGURE 3

(a,b) Frequency distribution of the individuals responsible (Medical Physics Trainee or Qualified Medical Physicists) for the initial plan checks (a) and weekly physics checks (b) on patients' treatments undergoing radiotherapy using a 5‐point Likert scale (1 = Never, 2 = Rarely, 3 = Sometimes, 4 = Often, 5 = Always).