After salivary gland cancer surgery, how can radiotherapy decisions be personalized?

An international original research study explained for patients and families.

What did the researchers investigate?

Published in 2026 in Radiotherapy and Oncology, this study analyzed 1,175 patients who underwent surgery for cancer of the major salivary glands — parotid, submandibular or sublingual — at five cancer centres in Canada, the United States and Brazil. With Gustavo Nader Marta among the authors, the team developed a nomogram: a risk-calculation tool that combines tumour and treatment features to estimate the likelihood of cancer returning in the treated area or nearby lymph nodes within five years.

What did the study find?

The model incorporates factors such as tumour type and extent, cancer cells at the surgical margins, invasion of blood or lymphatic vessels, lymph-node involvement and whether postoperative radiotherapy was used. In one model-based example, estimated five-year local or regional recurrence risk was 20% without radiotherapy versus 11% with radiotherapy. These figures are estimates for a particular risk profile, not precise predictions for every individual.

What could this mean for patients?

Rather than considering one risk factor alone, the tool combines several features to support discussions about the possible role of radiotherapy after surgery. It may help clinicians and patients consider whether additional treatment is more relevant in higher-risk situations and carefully discuss its need in lower-risk cases, alongside clinical guidelines and individual circumstances.

What are the important limitations?

This was a retrospective study, not a randomized trial. Differences between the estimated scenarios cannot, by themselves, prove that radiotherapy caused the observed reduction in recurrence risk. The model underwent internal validation, but still needs testing in independent patient groups. It is intended to support — not replace — personalized clinical judgement.

For education only; not a substitute for individual medical assessment.