Original title: Dose-volume predictors of post-radiation xerostomia in head and neck cancer: A systematic review
Jikai Zhou, Xuanhe Hou, Wenjie Liang, Frank Hoebers +4 · September 2026
Radiation therapy for head and neck cancer often causes severe dry mouth, a condition called xerostomiaDry mouth caused by too little saliva.. This happens because radiation harms nearby salivary glands that produce spit. Doctors try to avoid these glands, but they need clearer rules on safe radiation limits. Researchers reviewed fifty-one studies to see which radiation doses cause this damage. They tracked how much radiation reached different parts of the mouth. The mean dose to the parotid glandOne of the major salivary glands, located near the jaw and ear. on the side away from the cancer was the strongest predictor of dry mouth. Keeping this dose below 20 Gy helped preserve saliva, while doses over 24-26 Gy raised the risk of moderate-to-severe xerostomia. Radiation to both parotids near 26 Gy also mattered, but strict planning cutoffs remain unproven. Finally, radiation to the submandibular glands, oral cavity, and specific parotid substructures like ducts also affects dry mouth risk.
Imagine watering a garden with a hose that sprays in every direction. The flowers closest to the nozzle get the most water, and if you leave the hose there too long, those flowers die while the rest of the garden stays green. In this paper, the hose is the radiation machine aimed at a tumor in the head or neck, the flowers are the salivary glands, and the amount of water is the amount of radiation. The finding is that the gland on the side away from the tumor is the one to watch: keep its water below a certain level and it survives, let it get too much and the patient is left with a dry mouth.
People treated for head and neck cancer often end up with chronic dry mouth, which makes eating, speaking, and sleeping harder. This review of 51 studies and nearly 11,000 patients shows which dose limits actually predict that side effect, so radiation plans can be designed to spare the salivary glands that matter most.
The abstract does not establish a single universal dose threshold; support for specific numerical thresholds is limited. The roles of submandibular glands, oral cavity, and parotid substructures are reported as independent associations or emerging findings, not confirmed planning targets.
Ask anything about this paper. Answers come from its abstract, and say so when the abstract doesn't cover your question.
Dose-volume predictors of post-radiation xerostomia in head and neck cancer: A systematic review — Jikai Zhou, Xuanhe Hou, Wenjie Liang et al. — Clinical and translational radiation oncology — doi:10.1016/j.ctro.2026.101282
Abstract licence: CC BY
Explanation generated by Synthesis from the abstract — it is not the original paper.