Try harder next time.
We’ve learned that knowledge of the best feasible dose to organs-at-risk can help planners reduce organ at risk (OAR) dose in head and neck plans. That’s because treatment planning is often based on staying below a set maximum allowable dose to an OAR instead of truly optimizing the dose as low as possible. In a similar vein, this study from UPenn took a look back at prior post-op head and neck plans in patients with HPV-associated oropharyngeal cancer. Patients received standard 60-64 Gy in 30-32 fractions. They used a set of OAR constraints that were more strict than standard national recommendations (see Table 2 for constraints). How feasible were these to achieve? All but one constraint was achieved in >50% of cases (mean larynx dose <20Gy, achieved 16.3%). In fact, 3 OAR constraints were achieved in >75% of cases (contralateral parotid mean<20Gy, 91.3%; contralateral submandibular mean <30Gy, 77.2%; esophagus mean<20Gy, 83.7%). So, your head and neck plans could be significantly improved by simply asking for stricter constraints. | Su, Pract Radiat Oncol 2022