Hypofractionation and the Global Access Gap in Radiotherapy

For lung cancer, if the patient is operable, surgery is the treatment of choice. If a patient is medically inoperable due to comorbidity, we give SBRT, whether it is a primary early-stage lung cancer or a lung metastasis from elsewhere, such as breast cancer. Dose depends on tumour location: ultracentral tumours, close to the heart or mediastinum, get a more cautious regimen of around 60 to 70 Gy in 7 to 10 fractions; peripheral tumours can get 50 Gy in 5 fractions, or sometimes 55 Gy in 5 fractions. We follow established SBRT dose-constraint guidelines for all of this.

It depends heavily on where the tumour sits. In fractionated radiosurgery for brain tumours, the incidence of radiation necrosis runs below 10 percent, and brain edema is another recognised complication. Risk rises when the target is near a critical structure such as the motor cortex or brainstem; robust dosing data for the motor cortex are limited, but the working figure for a single SRS session is around 15 Gy to that structure. With fractionated SRT or SRS, clinicians have to be especially vigilant about the proximity of organs at risk during planning. Done with that vigilance, SRS can be delivered safely to metastatic brain lesions with minimal complications, though it demands real expertise and careful dose painting.

I have treated around ten pediatric patients from Ethiopia specifically, as part of a broader pediatric caseload. Pediatric malignancy needs to be treated very carefully. In medulloblastoma, for example, craniospinal irradiation planning has to be extremely precise to prevent radiation-related toxicity. Because survival in cancers like ependymoma and medulloblastoma is often good, the most important concern becomes preventing secondary malignancy later in life, which means paying close attention to low-dose spillage, or integral dose, across the whole treatment field. For pediatric cases needing long treatment fields, we generally use tomotherapy, and we get very good outcomes.

It depends on the site and the stage. In early-stage head and neck cancer, surgery alone can be sufficient, but high-risk features on post-surgical pathology can still require adjuvant radiotherapy. In locally advanced disease, radiotherapy is generally needed as part of definitive treatment. In stage IV disease, radiotherapy is mostly palliative: relieving pain, bleeding, cord compression or hemoptysis. More than 50 to 60 percent of patients need radiotherapy at some point, whether as radical treatment, adjuvant therapy or palliation, and we rely on a multidisciplinary tumour board to decide the exact timing for each patient.

We follow international guidelines. Using cervical cancer as an example: stage IA, IB and IIA disease is treated with surgery first. Adjuvant treatment then depends on the Sedlis and Peters criteria: positive margins or positive nodes call for concurrent chemoradiation; deep stromal invasion beyond one-third, a tumour over 4 centimetres, or lymphovascular space invasion, without positive margins or nodes, call for radiation alone; if none of those features are present, no adjuvant treatment is needed and the patient goes to follow-up. Locally advanced disease, stage IB3 to IVA, needs concurrent chemoradiation. Stage IVB generally starts with chemotherapy, though a bulky tumour or high nodal burden may call for six weeks of neoadjuvant chemotherapy before concurrent chemoradiation. Every site, endometrium, lung, breast, has its own guideline, and we make these calls through tumour board discussion.

Hypofractionation delivers a larger radiation dose per treatment session across fewer overall sessions than conventional fractionation. In breast cancer, this shift moved standard treatment from 25 fractions to 15 fractions, and more recently to a 5-fraction schedule for selected patients under the FAST-Forward protocol.

Prostate cancer has a low alpha-beta ratio, around 1.2 to 1.5, a radiobiological trait that makes the tumor respond unusually well to larger doses delivered per fraction, making it a natural fit for hypofractionated regimens.

The UK's START trials, along with ESTRO and NCCN guidance, support hypofractionation across a widening range of clinical scenarios, and the ESTRO-ACROP 2022 consensus statement extends that support to ultra-hypofractionation in selected patients.

At least 25 percent of patients who need radiotherapy do not currently receive it, and demand is projected to keep rising while treatment capacity in many regions has not kept pace. Universal access by 2035 could save close to one million additional lives every year worldwide.

Yes. Radiotherapy is a non-invasive treatment, and most patients continue working and carrying on with daily life throughout a course of treatment, which is part of why shorter, hypofractionated courses deliver value beyond the purely clinical.