Homo or hetero?

We’d like to revisit a previous QuadShot reporting the Cleveland Clinic lung SBRT experience. A big controversy is whether to generate homogeneous or heterogeneous doses within the target volume. The heterogeneous camp would point out that higher effective doses improve tumor control, particularly in lung cancer, while maximizing dose fall-off in normal tissue. The Cleveland Clinic experience is rather unique among large academic experiences for two reasons. First, they’re in the homogeneous camp with most hot spots <110%. Second, they usually delivered treatments daily instead of every other day. Both of these fly in the face of lung SBRT protocol dogma, but their successful results speak for themselves. And in their defense, larger moderate dose volumes outside the target may actually be associated with reduced distant failure. TBL: Despite theoretical advantages with heterogeneous doses, there is clinical data to support homogeneous approaches. | Stephans, Int J Radiat Oncol Biol Phys 2018