Radiotherapy During COVID-19: Why Every Session Still Matters

The COVID-19 pandemic disrupted cancer care worldwide. Many radiotherapy treatments were unexpectedly interrupted as patients and healthcare workers had to isolate. In their study published in Radiation Physics and Chemistry, Professors R. G. Dale and B. Jones analyzed how these interruptions affected cancer control and what could be done to minimize the impact.

They found that each missed day of treatment can reduce the chance of tumor control by 0.8–1.6%, especially in fast-growing cancers such as those of the head and neck, cervix, or lung. The key problem is not the missed fraction itself but the extension of the total treatment time—the longer the treatment lasts, the more opportunity surviving cancer cells have to regrow, a process known as accelerated tumor repopulation.

In the United Kingdom, the Royal College of Radiologists issued clear guidelines dividing patients into three priority categories:

1. Fast-growing tumors that must not be delayed.
2. Slower-growing cancers that can tolerate minor gaps.
3. Palliative cases, where time is less critical.

To manage interruptions, clinicians used radiobiological modeling—calculating the biologically effective dose (BED)—and practical measures such as adding weekend sessions, providing two treatments per day (at least six hours apart), or slightly adjusting the dose per fraction to keep treatment effectiveness without increasing side effects.

Beyond clinical adaptation, the pandemic revealed a larger issue: the need for stronger education in radiobiology for all radiotherapy professionals—doctors, physicists, and technologists alike. Understanding how time, dose, and biology interact is essential to deliver safe, effective care under any circumstance.

For patients in Costa Rica and around the world, the lesson remains the same:
Never stop radiotherapy without consulting your oncologist.
Each session is a building block toward cure. Even during crises, perseverance and teamwork in Radiation Oncology ensure that the beam of hope never fades.