Would you consider the thymus as an OAR during treatment planning for advanced NSCLC?

With any avoidance, the dose is pushed further somewhere else, with often unclear effects. You really can rob Peter to pay Paul. I reckon that, as automated, AI-guided OAR contouring occurs, many substructures can be feasibly and reliably drawn and then monitored for associated late effects. It is going to hinge on the robust treatment planning system, monitoring of patients' outcomes, and large numbers to tease out what is important and in what order. What might be true at one institution may not be valid for another. Trust but verify. If multiple studies across a variety of institutions and countries validate a parameter, then I am likely to trust it. I would start with a foundation of what is well known and bind the plan to that: normal ...

Personally, I'd like to see these findings reproduced in at least two other retrospective studies before I would consider them real. If validated, it's time for more rad oncs to use the D2cm and R50 tables when designing IMRT plans to clamp down on intermediate doses that might otherwise spill into the thymus. For transparency, I've adopted D2cm and R50 constraints for all IMRT plans since 2023.

DiGeorge Syndrome results from failure of the branchial pouches to develop the parathyroid and Thymus. The Thymus influences the development of the T lineage lymphocytes, surveillance, memory of infection, and all aspects of T-mediated immunity. The thymic “sail” sign in infants and children worried some to advocate radiation treatment: not helpful, indeed carcinogenic.

The thymus involutes, may be hard to find in adults. I’m ignorant of the known function in children and adults.

The phenomenon of lymphopenia with thoracic radiotherapy is known. Its cause, duration, and consequences have never been elucidated.

I don’t have access to the “hypothesis generating” article. As the natural history of Lung cancers includes distant spread, teasing out...